Dissertations / Theses on the topic 'Cross pollination'

As a music student who was always more attracted to the “academic” side of music rather than the performance side, I have come to hold a great respect for music history. This interest only grew when I got the opportunity to study music for a semester in Edinburgh, Scotland. Being surrounded by so much history, both musical and artistic, only fed my passion. I began to notice many similarities between the development of music and art both during lectures at the university and in my leisure time in galleries. I noticed that composers and visual artists in the same time period would hold similar beliefs or thoughts, therefore similarities could be found between the two art forms. Oftentimes, I would come across a composer whose compositional techniques were directly influenced by an artist and/or vice versa. I became interested in this type of cross-pollination in music and soon began to ask myself the question “Have the development of art and music always been influenced by each other? How many composers were inspired by art?” When it came time to begin my honors thesis, I decided to address this topic. So, I chose to explore this type of cross-pollination in music and, in conjunction with this research, create my own musical composition based on a work of visual art of my own choosing. Specifically, I wanted to look more carefully at the technique composers had used historically to connect their pieces of music with particular pieces of visual art. I therefore chose several art-influenced compositions to examine how the music expresses the art. In the first chapter of my thesis, I discuss the problem of turning spatially existing art into a temporally existing composition and explore several compositions in which the composers chose to construct a musical narrative as an approach to this challenge. In the second chapter, I revisit the problem of turning art into music but instead explore a different set of compositions that overcome this issue using a ‘snapshot’ technique. In the third chapter, I take a look at ekprasis as a technique used to translate abstract art into music and focus on how one composition in particular expresses the artwork. The fourth chapter is a journal discussing the art I have chosen, the stages in my compositional process, and how I used what I learned from my research to create my own composition. I have included the score of my composition as the fifth chapter.

Thesis (MScAgric)--University of Stellenbosch, 2000.
ENGLISH ABSTRACT: Ineffective pollination of the main cultivar with the pollinator cultivar is due to either an incompatibility problem between the main and pollinator cultivar, or because the flowering times of the main and pollinator cultivars do not overlap adequately. Three trials were conducted to try and find a more effective way to determine cultivar compatibility and to group cultivars together according to their budburst reaction to chilling. Most apple cultivars are self-incompatible and need cross-pollination for fruit set. Due to differences in the genetically defined fertilisation compatibility between the pollen from the male parent (pollinator) and the egg cell of the female parent, various apple pollinators differ in their ability to set fruit with viable seed. Fruit weight and size are positively correlated with seed set although it has been found that the pollinator can have a direct influence on fruit quality. 'African Red' apple trees on M7 rootstock in an evaluation block on a commercial farm in the Koue Bokkeveld region (32°55'N 19°27'E, Mediterranean climate, ;::::1060Utah chill units, and ;::::530mm rainfall annually; altitude 966 m) were used to assess the influence of 5 pollinators ('Granny Smith', 'Winter Banana', 'Cripps' Pink', 'Cripps' Red' and 'Simpson Crab') on fruit set, fruit weight and length and diameter. The degree to which 'African Red' is self-compatible was also assessed and the effect of flowering position ("king" vs. lateral) on fruit quality was determined. None of the pollinators showed a significantly higher fruit set. No differences in fruit set were found between the "king" and lateral flowering positions. No significant differences were found in the average number or weight of well developed seeds between pollinators. In both years fruit weight was significantly correlated to seed number for all five pollinator cultivars. In 1998 'Simpson crab' gave fruit that were significantly more elongated than those of 'Cripps' Pink'. 'African Red' is highly self incompatible. Compatibility assessments that are based on the number of fruit that develop after the flowers ofthe main cultivar had been hand pollinated in field trials are a time-consuming process. Allele-specific PCR amplification for some of the known S-alleles of the incompatibility S-gene (S2, S3, S5, S7 and S9) was carried out to successfully predict the compatibility of genotypes. The results compared well with that found in literature. For all the Malus domestica cultivars tested at least one, but in some instances both alleles of the S-gene were determined. 'Simpson crab' (Malus baccata) did, however, not possess any of the tested S-alleles. One-year-old, ca. 40 mm long shoots of various apple cultivars were selected from commercial orchards in both the Elgin [34°S, 305 m, ca. 750 chill units (CU) (Richardson et al., 1974)] and Koue Bokkeveld (33°S, 945 m, ca. 1300 CU) regions of the Western Cape, South Africa in two consecutive years (1998 and 1999). Shoots were forced at a constant 25°C with continuous illumination after receiving their allocated chill units. The effect of chilling period on the budburst of each cultivar in both regions was estimated by determining, 1) the total proportion of budburst (%Bb), 2) the proportion of shoots with terminal budburst (%TBb), and 3) the rate of budburst [lI(days to 25% budburst)]. It was found that these indices differed significantly between cultivars, and within cultivars between areas, as far as budburst patterns, in reaction to chilling, were concerned. The rate of budburst was the most consistent in describing the reaction of buds to different chilling periods and could be used to group cultivars together according to their budburst reaction to chilling.
AFRIKAANSE OPSOMMING: KRUISBESTUIWINGSBIOLOGIE VAN APPELS MET SPESIALE VERWYSING NA 'AFRICAN RED'. Oneffektiewe kruisbestuiwing III die boord kan toegeskryf word aan Of onverenigbaarheid tussen die hoof- en bestuiwingskultivar Of as gevolg van die blomtyd van die kruisbestuiwer wat nie genoegsaam oorvleuel met die van die hoofkultivar nie. Drie proewe is uitgevoer om 'n meer effektiewe proses daar te stel vir die toets van kultivarverenigbaarheid en om kultivars te probeer groepeer na gelang van hul reaksie op bepaalde hoeveelhede koue. Meeste appelkultivars is selfonverenigbaar en benodig kruisbestuiwing vir genoegsame vrugset. As gevolg van verskille III die geneties gedefinieerde bevrugtingsverenigbaarheid tussen die stuifmeel van die manlike ouer (bestuiwer) en die eiersel van die vroulike ouer (hoofkultivar), verskil bestuiwers in hul vermoë om vrugte met sade te set. Vruggrootte en -massa is positief gekorreleerd met saadset alhoewel dit al gevind is dat die bestuiwer op sig self ook 'n invloed op vrugkwaliteit kan hê. 'African Red' appelbome op M7 onderstamme, in 'n evaluasie blok op 'n kommersiële plaas in die Koue Bokkeveld (32°55'N 19°27'E, Meditereense klimaat, ::::1060 Utah koue eenhede, en ::::530mmjaarlikse reënval; ligging 966 m), is gebruik om die invloed van 5 bestuiwers ('Granny Smith', 'Winter Banana', 'Cripps' Pink', 'Cripps' Red' and 'Simpson Crab') op vrugset, vrugmassa, -lengte en -deursnee oor twee seisoene te bepaal. Die mate waartoe 'African Red' self onverenigbaar is en die effek van blomposisie ("king" vs laterale blom) op vrugkwaliteit is ook bepaal. Geen een van die bestuiwers het vrugset beduidend beïnvloed nie. Ook is daar geen verskille gevind tussen die "king" en laterale blomposisies t.o.v. vrugset nie. Geen beduidende verskille is tussen bestuiwers gevind in die gemiddelde aantal of gewig van volsade geset nie .. In albei jare was die vrugmassa beduidend gekorreleerd met saadset vir al vyf bestuiwerkultivars. In 1998 het 'Simpson Crab' vrugte geset wat beduidend langer was as vrugte wat geset het toe 'Cripps' Pink' as bestuiwer gebruik is. Daar is ook gevind dat 'African Red' hoogs selfonverenigbaar is. Verenigbaarheidstoetse wat gebaseer is op die aantal vruggles wat ontwikkel nadat blomme van die hoofkultivar met die hand bestuif is, is 'n tydsame proses. Allele spesifieke PCR amplifikasie vir bekende S-allele van die onverenigbaarheids S-geen (S2, S3, S5 S7en S9) is suksesvol uitgevoer om die verenigbaarheid van genotipes vooraf te bepaal. Die resultate het goed vergelyk met wat in literatuur gevind is. Vir al die Malus domestica spesies wat getoets is, is ten minste een, en in sommige gevalle twee, van die S-allele gevind. Die blomappel 'Simpson' (Malus baccata) het egter nie een van die vyf S-allele opgelewer nie Een-jaar-oue, 40 mm lang lote van verskeie appelkultivars, is in twee opeenvolgende jare (1998 en 1999) vanuit kommersiële boorde in beide die Elgin [34°S, 305 m, ca. 750 koue eenhede (CU) (Richardson et al., 1974)] and Koue Bokkeveld (33°S, 945 m, ca. 1300 CU) areas van die Wes Kaap gsny. Die lote is geforseer om te bot by 'n konstante temperatuur van 25°C met deurlopende beligting, nadat elke groep lote aan 'n bepaalde hoeveelheid koue blootgestel is. Die effek van koue op bot van elke kultivar in beide areas is bepaal deur, 1) die totale persentasie knoppe wat gebot het, 2) die persentasie terminale knoppe wat gebot het, en 3) die tempo van bot [l/(dae tot 25% bot)] te meet. Daar is gevind dat bo-genoemde parameters beduidend tussen kultivars, en binne kultivars tussen areas, verskil. As 'n beskrywing van die reaksie van knoppe op koue het die tempo van bot die mees konstante resultate oor die twee opeenvolgende seisoene gelewer en kon hierdie parameter gebruik word om kultivars in groepe, na gelang van hul reaksie op koue, in te deel.

Written literature has evolved significantly over the centuries. The typical novel of the twenty-first century is different in form from the novel of the mid-nineteenth. Modern novels tend to have less descriptive exposition and are less apt to follow previous conventions of omniscient narration. What factors have influenced this change? At the end of the nineteenth century, for the first time in recorded history, a new art form emerged, one that was based on the technological achievement of the recorded moving image. This study examines to what extent, and in which ways, the new art form, cinema, has affected written literature, particularly the novel. What are the elements of cinema technique that have influenced writing on a structural level? How do they manifest themselves at a level of text? The research framework approaches these questions both theoretically and practically. The theoretical aspect examines sets of texts to see if anything definitive can be stated about this ‘cross-pollination’ of form. The investigative paradigm pursues avenues of research that incorporate structural analyses of texts and also the ways in which those texts operate at a level of mental processing. My intention is to concentrate more fully on ‘what those texts are doing’ rather than ‘what they are’. The approach is broadly ‘cognitive’, one that examines the processes that are undertaken during the reception of texts and during their production. The practical element of this framework is in the form of a novel, Jacks, which forms Volume 2 of this study. Here, the fictional account is designed to reflect aspects of the theoretical approach and to include subject matter pertaining to film and creative processes, to illustrate elements of the theory in a creative form. A final section proposes practical outcomes for the theory in the fields of creative writing practice and pedagogy.

California's almond industry, valued at $2.3 billion per year, depends on the pollinator services of honey bees, although pollination by other insects, mainly solitary wild bees, is being investigated as an alternative because of recent declines in the number of honey bee colonies. Our objective is to model the movements of honey bees and determine the conditions under which they will forage in less favorable areas of a tree and its surroundings when other pollinators are present. We hypothesize that foraging in less favorable areas leads to increased movement between trees and increased cross pollination between varieties which is required for successful nut production. We use the Shigesada-Kawasaki-Teramoto model (1979) which describes the density of two species in a two-dimensional environment of variable favorableness with respect to intrinsic diffusions and intra- and interspecific interactions of species. The model is applied to almond pollination by honey bees and other pollinators with environmental favorableness based on the distribution of flowers in trees. Using the spectral-Galerkin method in a rectangular domain, we numerically approximated the two-dimensional nonlinear parabolic partial differential system arising in the model. When cross-diffusion or interspecific effects of other pollinators was high, honey bees foraged in less favorable areas of the tree. High cross-diffusion also resulted in increased activity in honey bees in terms of accelerations, decelerations, and changes in direction, indicating rapid redistribution of densities to an equilibrium state. Empirical analysis of the number of honey bees and other visitors in two-minute intervals to almond trees shows a negative relationship, indicating cross-diffusion effects in nature with the potential to increase movement to a different tree with a more favorable environment, potentially increasing nut production.

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Pollination is presented as a determining factor in the production of fruits in various fruit species, especially those that do not reproduce by parthenocarpy. This study aimed to evaluate the influence of self-pollination and cross-pollination of jelly palm in production and fruit quality. To this end, we used 14 genotypes of jelly palm of BAG of FAEM-UFPel, RS, Brazil. The treatments were: non-bagging (T1) and bagging with TNT (T2). Evaluated: average production cycle (days), average fruit weight (g), the average mass of pulp (g), pulp yield (%), average mass of pyrenes (g), number of fruits, equatorial diameter of fruits (EDF), longitudinal diameter of fruits (LDF), equatorial diameter of pyrenes (EDP), longitudinal diameter of pyrenes (LDP), relationship LDF/EDF, relationship LDP/EDP, amount of juice (ml), average number of almonds/pyrene (NA/P), almonds brocade/pyrene (%AB/P), average mass unitarian of almonds (AMUA), without almonds pyrenes (%WAP), skin colorimetry (°Hue), soluble solids (°Brix), titratable acidity (TA) ratio (SS/TA), juice pH, ascorbic acid (mg.100ml-1 juice), average date of flowering (DF) and average date of harvest (H). Self-pollination of jelly palm caused a reduction of the overall rates in the variables average mass of fruit, fruit number, EDP, NA/P, %AB/P, TA and ascorbic acid, significantly increased the average mass of pulp, relationship LDF/EDF , relationship LDP/EDP, amount of juice (ml), AMUA, % PSA, SS, ratio and pulp yield (%). It was concluded that the bagging of clusters of jelly palm cause declines, in the production, of 49.31%. However, leads to improvement in the quality of the fruit. The fruits that have been deprived of cross-pollination resulted in increased pulp yield (2.87%). The cross-pollination is essential in genotypes G. 32, G. 35, G. 57 and G. 63, without it there is no fruit production.
A polinização apresenta-se como fator determinante na produção de frutos em várias espécies de fruteiras, em especial naquelas que não se reproduzem por partenocarpia. Esta pesquisa objetivou avaliar a influência da autopolinização e da polinização cruzada de Butia odorata (Barb. Rodr.) Noblick & Lorenzi na produção e na qualidade do butiazeiro. Para tal, foram utilizados 14 genótipos de butiazeiros do banco ativo de germoplasma (BAG) da FAEM-UFPel. Os tratamentos utilizados foram: não-ensacamento (T1) e ensacamento com TNT (T2). Avaliou-se: ciclo médio de produção (dias), massa média dos frutos (g), massa média de polpa (g), rendimento de polpa (%), massa média dos pirênios (g), número de frutos, diâmetro equatorial dos frutos (DEF), diâmetro longitudinal dos frutos (DLF), diâmetro equatorial dos pirênios (DEP), diâmetro longitudinal dos pirênios (DLP), relação DLF/DEF, relação DLP/DEP, volume de suco (em ml), número médio de amêndoas/pirênio (NA/P), amêndoas brocadas/pirênio (%AB/P), massa média unitária de amêndoas (MMUA), pirênios sem amêndoas (%PSA), colorimetria da epiderme (°Hue), sólidos solúveis (°Brix), acidez titulável (AT), ratio (SS/AT), pH do suco, teor de ácido ascórbico (em mg de AA.100ml-1 suco), data média de floração (DMF em dd/mm/aa) e data média de colheita (DMC em dd/mm/aa). A autopolinização dos butiazeiros provocou redução dos índices gerais nas variáveis massa média dos frutos, número de frutos, DEP, NA/P, %AB/P, AT e ácido ascórbico; aumentou de forma significativa a massa média de polpa, relação DLF/DEF, DLP/DEP, volume de suco, MMUA, %PSA, SS, Ratio e rendimento de polpa. Concluiu-se que o ensacamento de cachos do butiazeiro diminui a produção em 49,31%, todavia, provoca melhoria na qualidade das frutas. As frutas que foram privadas da polinização cruzada resultaram em aumento do rendimento de polpa (2,87%). A polinização cruzada é fundamental nos genótipos G. 32, G. 35, G. 57 e G. 63, sem a qual não há produção de frutas.

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O fenômeno de xênia é descrito como o efeito direto do pólen no embrião e endosperma da semente, alterando suas características genéticas e proporcionando mudanças qualitativas e quantitativas. Vários caracteres do grão de milho como cor, tamanho, peso e teor de alguma substância apresentam esse efeito. Portanto existe a possibilidade deste fenômeno ser explorado com o cultivo de dois híbridos com sementes misturadas, buscando-se um aumento no rendimento da lavoura. O objetivo deste trabalho foi identificar pares de híbridos, em duas épocas de semeadura, que apresentem efeito xênia para os caracteres tamanho de grãos, peso médio de grãos e conteúdo de óleo e proteína. O trabalho foi conduzido na Fazenda de Ensino e Pesquisa da Faculdade de Engenharia de Ilha Solteira - UNESP, localizada no município de Selvíria - MS. Foram avaliados todos os pares possíveis, incluindo os recíprocos, entre os híbridos AG 8080, DKB 333B, DAS 32, P 30F80, TORK e XB 8010, sob delineamento estatístico de blocos casualizados com quatro repetições na primeira safra e três na segunda safra (safrinha). A polinização de cada híbrido (cruzamento ou sib) foi realizada manualmente em cada parcela, de acordo com o tratamento especificado. As análises indicaram efeito xênia de 15%, no peso médio dos grãos do híbrido XB 8010 quando polinizado pelo TORK, na primeira safra, quando em comparação com o XB 8010 polinizado com seu próprio pólen. Na Segunda safra o híbrido DKB 333B proporcionou um aumento de 20% no peso médio dos grãos do AG 8080. Para conteúdo de proteína, o efeito xênia foi significativo e negativo (-9,0%) quando o híbrido DKB 333B recebeu pólen do híbrido TORK, na primeira safra, e nos demais cruzamentos não houve influência da fonte polinizadora. Para o caráter conteúdo de óleo, a manifestação do efeito xênia ocorreu nas duas épocas... .

Orientador: João Antonio da Costa Andrade
Banca: Maria Elisa Ayres Guidetti Zagatto Paterniani
Banca: Pedro César dos Santos
Resumo: O fenômeno de xênia é descrito como o efeito direto do pólen no embrião e endosperma da semente, alterando suas características genéticas e proporcionando mudanças qualitativas e quantitativas. Vários caracteres do grão de milho como cor, tamanho, peso e teor de alguma substância apresentam esse efeito. Portanto existe a possibilidade deste fenômeno ser explorado com o cultivo de dois híbridos com sementes misturadas, buscando-se um aumento no rendimento da lavoura. O objetivo deste trabalho foi identificar pares de híbridos, em duas épocas de semeadura, que apresentem efeito xênia para os caracteres tamanho de grãos, peso médio de grãos e conteúdo de óleo e proteína. O trabalho foi conduzido na Fazenda de Ensino e Pesquisa da Faculdade de Engenharia de Ilha Solteira - UNESP, localizada no município de Selvíria - MS. Foram avaliados todos os pares possíveis, incluindo os recíprocos, entre os híbridos AG 8080, DKB 333B, DAS 32, P 30F80, TORK e XB 8010, sob delineamento estatístico de blocos casualizados com quatro repetições na primeira safra e três na segunda safra (safrinha). A polinização de cada híbrido (cruzamento ou "sib") foi realizada manualmente em cada parcela, de acordo com o tratamento especificado. As análises indicaram efeito xênia de 15%, no peso médio dos grãos do híbrido XB 8010 quando polinizado pelo TORK, na primeira safra, quando em comparação com o XB 8010 polinizado com seu próprio pólen. Na Segunda safra o híbrido DKB 333B proporcionou um aumento de 20% no peso médio dos grãos do AG 8080. Para conteúdo de proteína, o efeito xênia foi significativo e negativo (-9,0%) quando o híbrido DKB 333B recebeu pólen do híbrido TORK, na primeira safra, e nos demais cruzamentos não houve influência da fonte polinizadora. Para o caráter conteúdo de óleo, a manifestação do efeito xênia ocorreu nas duas épocas... (Resumo completo, clicar acesso eletrônico abaixo).
Astract: The xenia phenomenon is described as the direct effect of the pollen in the seeds's embryo and endosperm, altering their genetic traits and providing qualitative and quantitative changes. Several grain traits as color, size, weight and contents any substance, presents this effect. Therefore there is possibility of this phenomenon to be explored with the cultivation of two hybrids with mixture of seeds, seeking for a increase in the yield. The goal of this work was identify hybrid pairs for the traits grains medium weight, grains size and the oil and protein content, that show xenia effect in two sowing season. Were appraised all the pairs possible, including the reciprocal ones, among the hybrids AG 8080, DKB 333B, DAS 32, P 30F80, TORK and XB 8010, in a complete random block design, with four replicates at normal season and three replicates at no season crop. The pollination (cross and sib) of each hybrid, were realized manually in each plot, under the specified treatment. The analyses indicated 15 % of xenia effect in the grains medium weight of the hybrid XB 8010 as pollinated by TORK, at normal season, as compared with XB 8010 pollinated by your self pollen. In no season crop the hybrid DKB 333B provided an increase of 20% in the grains medium weight of AG 8080. For the protein content, the xenia effect was significant and negative (-9,0%) when the hybrid DKB 333 received pollen of TORK, at normal season, and the of others crossing have not influence the pollen, showing a larger maternal effect. For the trait oil content the xenia effect showed up in two sowing season. At normal season the pollen of hybrid DKB 333B changed significantly the grains oil percentage of AG 8080 (15%) and TORK (14%). In no season crop, the pollen of P 30F80 and DKB 333B increase in 20% and 21% the oil contents of DAS 32 and P 30F80, respectively. Therefore it was... (Complete abstract, click electronic address below).
Mestre

Thesis (PhD)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Insect pollination contributes in various degrees toward the production of a variety of agricultural crops that ensure diversity and nutritional value in the human diet. Although managed honeybees (Apis mellifera L.) are still the most economically valuable pollinators of monoculture crops cultivated globally, wild pollinator communities can contribute substantially toward crop pollination through pollination ecosystem services sourced from neighbouring natural habitats. Pollination ecosystem services are thus valuable and can motivate for the protection of natural ecosystems hosting diverse insect pollinator communities. F1 onion hybrid seed production is entirely dependent on high insect pollinator activity to ensure cross pollination, seed set and profitable seed yields. Data was collected on 18 onion hybrid seed crops grown in the semi‐arid Klein Karoo and southern Karoo regions of the Western Cape, South Africa. These two main production regions are located within the Succulent Karoo biome, recognized as a global biodiversity hotspot of especially high plant diversity. It is also habitat to the indigenous Cape honeybee (Apis mellifera capensis Esch.). Sites selected varied in the percentages of available natural habitat and managed honeybee hives stocking density. Diverse anthophile assemblages were sampled with pan traps within all the onion fields, regardless of the percentage of available natural habitat near the crop. Crop management practices significantly affected the diversity of anthophile species caught within onion fields, although less than 20% of this diversity was observed actually visiting onion flowers. The honeybee (managed and wild) was by far the most important pollinator because of its high visitation frequency and regular substantial onion pollen loads carried on their bodies. Honeybee visitation significantly increased onion hybrid seed yield, while anthophile diversity and non‐Apis visitation had no effect on seed yield. Neither managed hive density, nor percentage natural habitat were important in determining honeybee visitation or seed yield. Total annual rainfall was the only significant factor determining honeybee visitation. Secondary factors caused by rainfall variability, such as wild flower abundance or soil moisture, may have significantly affected honeybee visitation. In addition, the positive correlation between honeybee visitation and the diversity of hand‐sampled insects from onion flowers; indicate that either or both onion varietal attractiveness and/or pollinator population size may have had significant effects on overall insect visitation. Honeybees showed marked discrimination between hybrid onion parental lines and preferred to forage on one or the other during single foraging trips. Hybrid onion parents differed significantly in nectar characteristics and onion flower scent which would encourage selective foraging through floral constancy. Interspecies interactions were insignificant in causing increased honeybee pollination because of the scarcity of non‐Apis visitors. Most farming practices are subjected to favourable environmental conditions for successful production. However, and especially in the South African context, the dependence of onion hybrid seed crops on insect pollination for successful yields, increase its reliance on natural ecosystem dynamics that may deliver abundant wild honeybee pollinators, or attract them away from the crops. Nevertheless, this dependence can be mitigated effectively by the use of managed honeybee colonies to supplement wild honeybee workers on the flowers.
AFRIKAANSE OPSOMMING: Insek bestuiwing dra in verskillende grade by tot die produksie van landbou gewasse wat variteit en voedingswaarde in die mens se dieet verseker. Al is die heuningby (Apis mellifera L.) steeds die waardevolste ekonomiese bestuiwer van verboude enkelgewasse, kan wilde bestuiwers wesenlik bydra tot gewasbestuiwing deur middel van ekosisteem dienste afkomstig van natuurlike habitatte. Bestuiwing ekosisteem dienste is daarom waardevol en kan dus die bewaring van natuurlike ekosisteme, wat diverse gemeenskappe huisves, regverdig. F1 basterui saadproduksie is totaal afhanklik van hoë insek‐bestuiwer aktiwiteit om kruisbestuiwing, saadvorming en winsgewende saadopbrengste te verseker. Data is ingesamel op 18 basterui saad aanplantings in die half‐droë Klein Karoo en suid‐Karoo streke van die Weskaap, Suid‐Afrika. Hierdie twee hoof produksie streke is geleë binne die Sukkulente Karoo bioom wat erken word as ʼn globale biodiversiteits “hotspot” met hoë plant diversiteit. Dit is ook die habitat van die inheemse Kaapse heuningby (Apis mellifera capensis Esch.). Aanplantings is gekies om verskillende grade van beskikbare natuurlike habitat en bestuurde heuningby korf digthede te verteenwoordig. Diverse versamelings blom‐besoekers is versamel met water‐wippe in al die aanplantings, ongeag die persentasie natuurlike habitat beskikbaar by elke aanplanting. Gewas bestuurspraktyke het die diversiteit van blombesoekers betekenisvol beïnvloed. Tog is minder as 20% van hierdie diversiteit as aktiewe besoekers op die uiekoppe waargeneem. Heuningbye (bestuur of wild) was oorwegend die belangrikste bestuiwers as gevolg van hoë besoek frekwensies en wesenlike ladings uiestuifmeel op hulle liggame. Heuningby besoeke het saadopbrengs betekenisvol verhoog, maar blom‐besoeker diversiteit en nie‐Apis besoeke het geen effek op saadopbrengs gehad nie. Bestuurde korf digtheid en persentasie natuurlike habitat was nie belangrik in die bepaling van heuningby besoeke of basterui saadopbrengste nie. Totale jaarlikse reënval was die enigste betekenisvolle faktor wat heuningby besoeke bepaal het. Sekondêre faktore wat versoorsaak word deur reënval veranderlikheid, soos veldblom volopheid of grondvog, kon betekenisvolle effekte op die aantal heuningby besoeke gehad het. Bykomend, dui die positiewe korrelasie tussen heuningby besoeke en die diversiteit van hand‐versamelde insekte vanaf die uiekoppe op die moontlike betekenisvolle effek van elk of beide basterui variteit aantreklikheid en/of bestuiwer populasie grote op algehele insek besoeke. Heuningbye het noemenswaardige diskriminasie getoon tussen die basterui ouerlyne en het verkies om op een of die ander te wei tydens enkele weidingstogte. Basterui ouerlyne het betekenisvol verskil in nektar eienskappe en blomgeur wat die selektiewe weiding van heuningbye, toegepas deur blomkonstantheid, sal aanmoedig. Tussen‐spesie interaksies was onbetekenisvol in die verhoging van heuningby bestuiwing omdat nie‐Apis besoekers baie skaars was. Meeste boerdery praktyke is onderhewig aan gunstige omgewings toestande vir suksesvolle produksie. Maar, en veral in die Suid‐Afrikaanse konteks, omdat basterui saad aanplantings afhanklik is van insek bestuiwing vir suksesvolle opbrengste, word daar meer staat gemaak op natuurlike ekosisteem dinamika wat volop wilde heuningby bestuiwers kan voorsien, of selfs bestuiwers van die aanplanting kan weg lok. Nietemin, hierdie afhanklikheid kan effektief verlaag word deur die gebruik van bestuurde heuningby kolonies om die aantal wilde heuningby werkers op die blomme aan te vul.

Unlike other rosaceous fruit crops such as apple and cherry, commercial raspberry cultivars are largely self-fertile and can set fruit in the absence of pollinators. However, their floral morphology often prevents complete self-pollaintion. Incomplete pollination yields unmarketable small or crumbly fruits. Insect visitation is therefore essential to maximizing raspberry yield. Honey bees are typically used to pollinate commercial raspberry; however, escalating prices for hive rentals coupled with increasing acreage encourage evaluation of other manageable pollinators. Bumble bees (Bombus spp.) and several mason bees (Osmia spp.) are promising raspberry pollinators. Five bee species were evaluated and compared for their single-visit pollination efficacies on raspberry. From this a pollinator effectiveness index was created and an estimation of the minimum number of visits required to maximize fruit set was calculated. This estimation was then experimentally verified. Finally, in an attempt to synchronize their brief activity period with raspberry bloom, winter management options aimed at delaying the emergence of the mason bee, O. lignaria, were investigated. All five bee species proved excellent pollinators of raspberry. None of the alternative manageable species greatly outperformed honey bees. For this reason honey bees remain the most economical and practical option for open-field raspberry pollination. The adoption of alternative manageable bees could still be justified in other production systems, such as high-tunnel or greenhouse grown raspberry, which hamper honey bees’ ability to forage effectively. The pollinator effectiveness score for honey bees suggested that as few as two visits can achieve maximum fruit set. This estimate was confirmed through experimentation on three different red raspberry cultivars. For two of these cultivars, just one visit yielded drupelet counts similar to openly-pollinated flowers. This information can be used to help refine stocking density estimates for honey bees on raspberry. Wintering bees at 0° or -3° C rather than 4° C effectively delayed emergence of O. lignaria by more than a month without any impact on post-winter performance. These results suggest winter storage at near freezing temperatures is a viable management option for the use of O. lignaria with later-blooming crops.

Increases in agricultural intensification over the past century have resulted in significant alterations to the rural landscape across the Midwest. Pollinators are essential to sustain natural and managed ecosystems. They are vital for food production and their declines have been linked, in part, to a rise in intensive agricultural practices. There is a recognized need among numerous stakeholders to build sustainability into the management of agroecosystems to protect both the biotic and abiotic resources of these systems. The use of cover crops is gaining interest among agricultural producers for benefits such as improving water quality and soil health. Cover cropping systems have the potential to provide floral resources to pollinators and suppress problematic driver weeds. The overall objective of this study was to quantify the effects of cover crops on plant and pollinator biodiversity within agricultural systems. This study aimed to characterize the pollinator diversity indicative of the patchwork mosaic forest-agroecosystem of Crab Orchard National Wildlife Refuge; evaluate the roles cover crop treatments play in supporting pollinator diversity and weed suppression benefits in a conventionally managed system; and provide the basis of recommendations for sustainable weed suppression tactics and for enhancing the quality of pollinator habitat within agricultural systems.

Sisyrinchium micranthum Cav. is an herbaceous plant, one of the rare species of the genus which is described as annual. In Brazil, its distribution occurs throughout the states of Rio Grande do Sul (RS), Santa Catarina (SC), Paraná (PR), São Paulo (SP), and Rio de Janeiro (RJ). The species has a wide morphological variability reported in several studies, and different combinations of morphological features can be observed in the wild. Based on these combinations that characterize various plant profiles, three morphological types have been described as CI, CII and CIII. Sisyrinchium micranthum has three ploidy levels described in the literature whose basic number is x = 8, 2n = 2x = 16, 2n = 4x = 32, and 2n = 6x = 48. To contribute to the knowledge on the taxonomy, reproduction and evolution of the species, this study investigated genetic and cytogenetic characteristics of S. micranthum, as well as aspects of reproductive biology. To study the population genetic structure of S. micranthum in southern Brazil, firstly, nine microsatellite markers were isolated using an enriched genomic library, and characterized in a diploid population. Later, from the analysis of genetic variability with seven markers for 583 plants of 14 sampled sites in the states of RS, SC and PR, populations with individuals of different ploidy levels were observed. An autopolyploid origin was presumed for these polyploids. The gene and allelic diversities were rather similar for most of the accessions. The inbreeding coefficient over all loci showed that S. micranthum exhibited an average excess of heterozygotes (negative inbreeding coefficient value), but the FIS values of individual populations ranged from -0.273 to 0.454. The heterozygote excess could be expected since autopolyploids present polysomic inheritance, which contributes substantially for a high heterozygosity. In addition, the populations were highly structured. The results from the cytogenetic analyses, demonstrated that the variability of S. micranthum is also present in terms of genome organization. Regarding S. micranthum and related species S. laxum Otto ex Sims and S. rosulatum E.P. Bicknell, it was verified that the 18S-26S rDNA varies in number of loci, with a notable reduction of the same in polyploids in relation to diploids, while 5S locus showed a proportional increase in the number of signals as increased ploidy level. The data on genome size (Cx) for the three species studied showed a genome downsizing from diploids to polyploids, and also a small inter and intraspecific variation with respect to the C-value. In terms of reproductive biology, selfing and outcrossing were recorded for the species. Furthermore, crossing between different morphological categories of S. micranthum are compatible as resulted in the formation of fruits. Likewise, the data suggest that S. micranthum and S. laxum do not present complete reproductive isolation. The genetic variability of S. micranthum demonstrated in this study in terms of genetic divergence between populations and variation in rDNA loci number possibly reflect the complex relationship between polyploidy and reproductive aspects of the species.

The overall aim of the study was to assess the risk of gene flow from Brassica crops by insectmediated pollen transport. I measured the viability of pollen in Brassica flowers throughout crop development and compared this with the viability of pollen transported by insects inside and outside one early- and one late-season crop. In order to evaluate the relative importance of different species in pollen transport, I measured abundance of flower visitors during crop development, and measured the foraging behaviour of five key pollinator species throughout the growing season, in relation to variation in microclimate, crop phenology and the relative abundance of other pollinator species competing for flower resources. Flower visiting insects of Brassica rapa crops were highly diverse, and their abundance and diversity changed with crop phenology. I found similar abundances at the family level for both crops studied, although capture rates were greater in the early- than in the late-season crop. Across flowering development, the greatest numbers of insects were captured at the peak of flowering for both crops. During the flowering period, Diptera was the most abundant order collected, followed by Hymenoptera. The most abundant family in Hymenoptera was Apidae which tracked crop development in both fields, with greater numbers of insects captured inside than outside the field. Standardized-count pollen loads were smaller in Diptera than in Hymenoptera. Of the five key pollinator species sampled, Lasioglossum sordidum (Hymenoptera: Halictidae), Apis mellifera (Hymenoptera: Apidae) and Bombus terrestris (Hymenoptera: Apidae) transported similar pollen loads, which were much greater than those carried by Eristalis tenax (Diptera: Syrphidae) and Melangyna novae-zealandiae (Diptera: Syrphidae). The numbers of insects captured outside of the crop were 10% and 33% of the totals captured inside for the early- and the late-season crop, respectively. The proportion of insects entering versus leaving the crop varied considerably across species, crops and trap location (i.e., whether traps were inside or 50 m outside the border of the crop). However, it is worth noting that not uncommonly more insects were attracted into the crop early in the season, staying there rather than leaving, and then when flowers started to disappear there was a massive escape of insects leaving. This research provides evidence for the influence of crop age on the foraging behaviour of key pollinators and for species-specific variation in the foraging behaviour of Brassica visitors with crop development. Temporal variation in the rate and variability of movement between flowers, and the duration and variability in time spent on each flower, throughout the growing season differed markedly between pollinator species. Flower density, plant density, and the abundance of other insects contributed to the observed variation in pollinator behavioural activity for A. mellifera, E. tenax, M. novae-zelandiae and L. sordidum. Bombus terrestris had the greatest rates and variability of movement, and the greatest rates of flower visitation among all key pollinators studied. Therefore B. terrestris might contribute to gene flow to a greater extent than other key pollinators. Additionally B. terrestris had the greatest variability in the rate of movement, increasing the risk of pollen movement over long distances. In summary, I found that (i) insect abundance and diversity changed with crop phenology and Diptera was the most abundant order collected, (ii) flower density, plant density, and the abundance of other insect pollinators were important factors explaining pollinator behaviour for all key pollinators, except B. terrestris, (iii) B. terrestris might contribute to gene flow to a greater extent than other key pollinators, because it has a greater rate of flower visitation and a greater flight distance between flowers than other pollinators, and (iv) pollen viability tended to decrease with crop development and declined sharply even just 50 m outside the edge of the crop.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES
This study aimed to investigate the acceptance of cavities with different lengths for nesting and the cavity size effects on the sex ratio and offspring mortality of solitary bees in two agricultural areas in Feira de Santana, Brazil. The samplings were carried out monthly, during 12 months, using trap-nesting (=NA) length 5, 10, 15 and 20 cm. A total of 124 nests, 591 building cells, and 479 emerging imago were sampled. There was a higher number of nesting in area I (n=86) than in area II (n=38). Centris analis Fabricius 1804, Centris tarsata Smith, 1874, and two Megachile species nested in ?rea I, being C. analis the specie with highest number of established nest (n=72, 83.7%), while other species had low nesting frequency (4%) and a higher bee richness, with six species occupying the trap-nesting. Tetrapedia diversipes Klug, 1810, established highest number of nest (n=29, 76.3%). Species used different NA size in both areas. In the area I, they nesting with higher frequency in NA with 10 cm (38%) and 15 cm (38%), while in the area II, there was cavity occupation with 20 cm (50%). Bees nested in most part of the year, except in months of autumn-winter, between April and August, when the bee nesting frequency was reduced or the activity was suspended. The natural enemies that emerged from the nests were species of Hymenoptera Coelioxoides sp, Mesocheira bicolor Fabricius, 1804, and a species of Chrysididae. The mortality rate by unknown reason in the areas I and II was 21.4% and 13.5% respectively, with higher incidence recorded to Centris analis. There was a higher mortality in smallest nests (5 cm) and there was no difference among the cavities with 10, 15, and 20 cm.
Este trabalho teve como objetivo investigar a utiliza??o de cavidades de diferentes comprimentos para confec??o de ninhos e os efeitos do tamanho da cavidade sobre a raz?o sexual e mortalidade da prole de abelhas solit?rias. O estudo foi conduzido em duas ?reas agr?colas no munic?pio de Feira de Santana, Bahia. Foram realizadas amostragens mensais durante 12 meses, usando ninhos-armadilha (NA) de comprimento 5, 10, 15 e 20 cm. Foram obtidos 124 ninhos, 591 c?lulas de cria constru?das e 479 imagos emergentes. Houve maior n?mero de nidifica??es na ?rea I (n=86) do que na ?rea II (n= 38). Centris analis Fabricius 1804, Centris tarsata Smith, 1874 e duas esp?cies de Megachile nidificaram na ?rea I, sendo C. analis a esp?cie com maior n?mero de ninhos estabelecidos (n=72, 83,7%), enquanto as outras esp?cies tiveram baixa freq??ncia de nidifica??o. A ?rea II apresentou menor freq??ncia de nidifica??o (4%) e maior riqueza de abelhas, com seis esp?cies ocupando os ninhos-armadilha. Tetrapedia diversipes Klug, 1810, estabeleceu maior n?mero de ninhos (n=29, 76,3%). As esp?cies utilizaram diferentemente os tamanhos de NA nas duas ?reas. Na ?rea I, as abelhas nidificaram com maior freq??ncia nos NA de 10 cm (38%) e de 15 cm (38%), enquanto na ?rea II houve maior ocupa??o das cavidades de 20 cm (50%). As abelhas nidificaram na maior parte do ano, com exce??o dos meses de outono-inverno, entre abril e agosto, quando a frequ?ncia de nidifica??o das abelhas foi reduzida ou a atividade foi suspensa. Os inimigos naturais que emergiram dos ninhos inclu?ram esp?cies de abelhas Coelioxoides sp, Mesocheira bicolor Fabricius, 1804 e uma esp?cie de Chrysididae. A taxa de mortalidade por causas desconhecidas nas ?reas I e II foi respectivamente 21,4% e 13,5%, com maior incid?ncia registrada em Centris analis. Houve uma maior mortalidade nos ninhos curtos (5 cm), n?o havendo diferen?a entre as cavidades de 10, 15 e 20 cm.

U  radu  je  prikazana  distribucija,  dinamika  i  diverzitet  insekata oprašivača iz reda Hymenoptera  -  Apiformes (Anthophila) i Diptera Syrphidae)  na  stepskim  fragmentima  i  na  suncokretu  u agroekosistema  Vojvodine.  U  cilju  uvida  u  strukturu  predela  injenog  uticaja  na  sastav  i  brojnost  polinatora,  kartirani  su  tipovistaništa  oko  svakog  stepskog  fragmenta.  Na  osnovu  podataka dobijenih kartiranjem, odabrano je sedam stepskih fragmenata kojiu  svom  okruženju  imaju  visok  udeo  suncokreta  kao  masovnocvetajuće  kulture  i  sedam  stepskih  fragmenata  koji  su  bez  ili  saniskim  udelom  suncokreta.  Iz  reda  Hymenoptera  –  Apoideazabeleženo  je  šest  familija:  Andrenidae,  Apidae,  Colletidae,Halictidae,  Melittidae  i  Megachilidae,  114  vrsta,  a  iz  reda  Diptera(Syrphidae),  registrovano  je  ukupno  11  vrsta.  Predstavnici  familija Andrenidae, Apidae i Halictidae su distribuirani na svim lokalitetima,predstavnici  familije  Megachilidae  su  distribuirani  na  15  od  16lokaliteta,  a  najmanje  su  zastupljene  jedinke  familija  Colletidae  iMelittidae,  distribuirane  na  pet  lokaliteta.  Polinatori  reda  Diptera familije  Syrphidae  su  distribuirani  na  svim  lokalitetima.  Rezultati Kruskal-Volisovog H testa ukuzuju da je tokom sve tri sezone (2011.,2012.,  2013.)  na  stepskim  fragmentima  najviše  bilo  zastupljeno vrsta  solitarnih  pčela,  zatim  vrsta  osolikih  muva,  a  najmanje  vrsta bumbara.  Istim  testom  je  dobijano  da  je  tokom  sve  tri  sezone  na stepskim  fragmentima,  registrovano  najviše  jedinki  osolikih  muva,zatim  medonosne  pčele,  solitarne  pčele,  a  najmanje  jedinki bumbara.  Fridmanovim  testom  su  utvrđene  razlike  u  brojnosti (dinamici)  polinatora  kroz  sezone,  uočen  je  porast  broja  jedinki medonosne pčele i opadanje broja jedinki solitarnih pčela.Rezultati  dobijeni  Man-Vitnijevim  U-testom  pokazuju  da  je  nastepskim  fragmentima  koji  imaju  niži  udeo  suncokreta  u  predelu zastupljeno  više  jedinki  i  vrsta  bumbara.  Istim  testom  je  dobijen rezultat  da  je  na  stepskim  fragmentima  sa  visokim  udelom suncokreta  ima  više  jedinki  medonosne  pčele.  Vilkoksonovim testom  sume  rangova  je  pokazano  da  su  jedinke  i  vrste  bumbara zastupljenije na stepskim fragmentima nakon cvetanja suncokreta, za  vreme  cvetanja  suncokreta  na  stepskim  fragmentima  je registrovano  više  jedinki  Apis  mellifera,  osolikih  muva  i  solitarnih pčela.  Modeli  regresionih  analiza  linearnih  mešovitih  modela  su pokazali  da  se  sa  porastom  udela  suncokreta  u  predelu  smanjuje broj jedinki divljih pčela i jedinki i vrsta bumbara. Sa porastom udela polu-prirodnih  staništa  u  predelu  i  većom  cvetnom  pokrovnosti, povećava se udeo jedinki i vrsta osolikih muva.
This  paper  shows  distribution,  dynamic  and  pollinator  diversity Hymenoptera  -  Apiformes  (Anthophila)  and Diptera (Syrphidae)  in semi-natural  habitats  and  in  sunflower  crops  in  Vojvodina  agroecosystems.  Around  each  of  16  selected  steppe  fragments,  habitat types  were  mapped  to  test  how  do  landscape  structure  affects pollinator  diversity  and  abundance  in  semi  natural  habitats  and  in sunflower  crops.  Based  on  the  results  obtained  by  mapping,  seven study sites with high % of sunflower like mass flowering crops, and eight  study  sites  with  no  or  low  %  of  mass  flowering  crops  are selected. In total, there were 114 species from 6 families  from order Hymenoptera-Apiformes:  Andrenidae,  Apidae,  Colletidae, Halictidae, Melittidae and Megachilidae, and 11 species from order Diptera  (Syrphidae).  Insects  from  families:  Andrenidae,  Apidae, Colletidae  and  Halictidae  were  distributed  on  all  study  sites,  while insects  from  family  Megachilidae  were  distributed  almost  on  all study  sites  (15  sites).  At  least  only  on  five  study  sites  were distributed insects from family: Colletidae and Melittidae. Hoverflies were distributed on all study sites.  Kruskal-Wallis H test shows that an  all  three  seasons  (2011.,  2012.,  2013.)  in  semi  natural  habitats wild bees species were most abundant, followed by hoverfly species, and bumblebee species at the end. Same test  shows that  in all three seasons in semi natural habitats individuals of hoverflies were more abundant than individuals of honey bees, wild bees  and individuals of  bumblebees,  which  were  least  abundant.  Friedman  test  shows differences in densities of pollinator through the seasons, and these results  shows  increasing  in  Apis  mellifera  densities  and  decline  of wild bees densities through seasons. Man-Whitney  U-test  shows  that  there  were  more  species  and individuals of bumble bees in semi-natural habitats which landscapes are without  or low % of sunflower. Same test shows that there were more  individuals  of  honey  bees  in  semi-natural  habitats  which landscapes  have  high  %  of  sunflower.  Wilcoxon  signed-rank  test shows  that  in  semi-natural  habitats  species  and  individuals  of bumblebees  were  more  abundant  after  blooming  sunflower,  while species  and  individuals  of  wild  bees  as  well  as  individuals  of hoverflies and  Apis mellifera  were  more abundant during blooming sunflower.  Linear mixed-effect model shows that with increase of % of  sunflower  in  landscape  number  of  individuals  of  wild  bees  and species and individuals of bumblebees decreasing, and individuals of hoverflies increasing. With an increase of % of semi natural habitats and  increase  of  flower  cover,  abundance  and  species  of  hoverfliesincreases.

碩士
國立成功大學
國際企業研究所
102
Borrowing the metaphor of “cross-pollination”, this research tries to clarify how the boundary-spanning resources are orchestrated and later utilized by certain actors in order to co-create value in the cultural and creative industries. Using the value co-creating system and orchestration perspectives to do the literature review. There are only few studies used for explaining these questions. Thus, using Hwang Sun Enterprise as the example to answer the research questions. The method of this research is qualitative case study which includes in-depth interview, second data collection and observation. There are several results as following: first of all, the relationship in the system is not rigid but flexible; secondly, “platform” in a system is necessary, and it is possible that there are more than one platform in the system; thirdly, the breakup of relationships will affect the co-creating process; fourthly, orchestrators can be different; finally, “school” should be supporting role in the system. From above results show, this research figures out that resources orchestrated by orchestrator(s) are based on the unique resources, abilities, and needs of orchestrators. On the other hand, “platform” should be exist when the tripartite, including HES, government and schools, do co-creation.

Mating success in plants depends largely on the efficiency of pollen dispersal. For hermaphrodite plants, self-pollination, either within or among flowers, can reduce mating opportunities because of pollen and ovule discounting and inbreeding depression. Self-pollination may be particularly detrimental in plants such as orchids and asclepiads that package each flower’s pollen into one or more pollinia which, together with accessory structures, comprise a pollinarium. Darwin proposed that physical reconfiguration of pollinaria serves as a mechanism for reducing the likelihood of self-pollination. To be effective, the time taken for pollinarium reconfiguration would need to exceed that spent by a pollinator on a plant. We investigated pollinarium reconfiguration (including pollinarium bending, pollinium shrinking and anther cap retention) in 19 species and found a strong positive relationship between reconfiguration time and the duration of pollinator visits. Reconfiguration times were also consistently longer than pollinator visit times. These results provide strong support for Darwin’s idea that this mechanism promotes cross-pollination.
Elsevier

Mestrado em Engenharia Agronómica - Instituto Superior de Agronomia
RESUMO Durante o ano de 2008, estudou-se o vingamento da cultivar de ameixeira japonesa ‘Angeleno’ em Campo Maior, Bombarral e Setúbal utilizando a cultivar Fortune como polinizadora. Nas 3 regiões, a eficácia da colocação sequencial de colmeias (T1) nos pomares e da utilização de um bioestimulante Göemar BM86® (T2) para auxílio de vingamento foi comparada com a prática comercial (T0), que consiste na colocação da totalidade das colmeias a 10% da floração. Dada a ocorrência de geada em Campo Maior, a análise do vingamento e da produção apenas foi realizada para Bombarral e Setúbal. Nestas regiões, o vingamento inicial registou médias de 7,33% em T0, 7,38% em T1 e 14,31% em T2. O comportamento relativo das modalidades manteve-se até à colheita, verificando-se uma densidade de colheita de 19,7 frutos/cm2 em T2, de 10,5 frutos/cm2 em T0 e de 9,5 frutos/cm2 em T1. Este acréscimo de vingamento em T2 não teve reflexos negativos na qualidade dos frutos, já que as classes de calibres se mantiveram homogéneas e todas superiores ao calibre mínimo comercializável. As condições climáticas afectaram fortemente os resultados, evidenciando a importância da sua análise na escolha do local para instalação de pomares de ameixeira. EXTENDED ABSTRACT Plum productivity is directly related with pollination and fruit set. Japanese plums carry a gametophytic self-incompability system, that prevents self-pollination or cross pollination with cultivars that harbor the same haplotypes. Therefore, cross pollination with compatible cultivars is an important requirement to ensure a suitable yield. Insects have to be introduced to promote pollen transfer ensuring that fruit set is achieved. In commercial orchards, fruit growers normally introduce bee colonies when 10% of the flowers are open. In this study, we compared this practice with an alternative practice consisting in the introduction of half of the bee colonies at 10% of the flowers open and the remaining part at full bloom. In addition, we also studied the effect of the application of a biostimulant, the Göemar BM 86®. This product is obtained from seaweeds (Ascophyllum nodosum) and is considered to induce beneficial effects on the growth of the pollen tube. This study was conducted in 2008 in three distinct regions of Portugal, namely in Bombarral (in the Oeste region), in Setúbal (40km South from Lisbon) and Campo Maior, near the border with Spain, located at the same latitude as Lisbon. The three orchards were certified to integrated pest management and they were planted about 15 years ago. In the three orchards, the cultivar studied was Angeleno and the polliniser used was the cultivar Fortune. During the growth cycle, flower number, the length and the diameter of the branches and the fruit set, at beginning, in an intermediate stage and at harvest (final fruit set) were counted. After the harvest the size of all fruits was measured and the weight was estimated according to a previously established linear regression. In order to evaluate the impact of the climate conditions, climate data of the three regions during the period of flowering and fruit set was recorded. Concerning flower number, flowering was more abundant in Campo Maior than in the other regions. In Campo Maior, the trees subjected to the Göemar BM86® treatment were severely affected by frost, therefore results were not fully conclusive. In the other two regions, the sequential introduction of bee colonies did not increase significantly the fruit set or any production parameter (size or weight of fruits). Additionally, the interaction between the treatments and locals was significant, showing the influence of climate conditions. Considering only Bombarral and Setúbal, initial fruit set was 7.33%, 7.38% and 14.31% in T0, T1 and T2 respectively. Final fruit set was 3.38%, 3.59% and 8.74%, in T0, T1 and T2 respectively. The highest values of fruit set in T2 resulted in a significantly higher crop density in T2 (19.7 fruits/cm2), compared to T0 (10.5 fruits/cm2) and T1 (9.5 fruits/cm2). Furthermore, fruits derived from trees treated with Göemar BM 86® had homogeneous size classes and all above the minimum size that is used commercially. This assay suggests that this growth regulator may have a beneficial effect in fruit setting in plum. However, it has to be considered that the application of such product implies three sprays, which may represent an additional cost (although Göemar BM 86® spraying may be combined with other products). One last consideration relates to the fact that weather conditions are of extreme importance and can determine the success of plum production, no matter which cultural practices are carried out. In our experiment, we verified that the climate conditions were as influent as cultural practices.

The floral and pollination biology of jujubes (Ziziphus mauritiana) and longans (Dimocarpus longan) were studied near Hanoi, Vietnam. Jujube is a protandrous species with three phases of flowering. After a brief asexual phase, anthers dehisce and release pollen in the afternoon of the day of anthesis. Stigmas become most receptive the following day when flowers are actively secreting nectar. Both jujube and longan flowers are visited during the day by insects of many families, particularly honeybees and flies (syrphids, calliphorids, and muscids). Honeybees, Apis cerana, made up 84% of floral visitors to jujube flowers and 47 – 95% to longan inflorescences. Bagging experiments revealed that diurnal insect visitors are very important in fruit production of both jujubes and longans. In jujubes, no fruits were set during the first pollination trial early in the flowering period. Fruit set increased to 0.17% midway through flowering and 2.21% for the trial conducted late in the flowering period. Fruit set recorded one week after anthesis suggested that all types of pollination may result in fruits, but 7 weeks after anthesis only open pollination (unbagged flowers) and diurnal pollination treatments yielded fruits. Most fruits (~97%) were estimated to result from honeybee visits to flowers. Longans are also predominantly pollinated by diurnal insects (~84%), but with minor contributions from wind pollination (8.4%) and self-pollination (7.7%). A. cerana was estimated to contribute 67% of longan pollination. Pollination requirements for 39 Vietnamese crops were reviewed. Most benefit from insect pollination. For 8 crops important in Vietnamese agriculture for which there were sufficient data, crop yields and values were estimated. Honeybee pollination resulted in ~50% of yields of these 8 crops, contributing ~900 millionion USD of their total values. This analysis indicates that the pollination service provided by honeybees is enormous.
Association of Universities and Colleges of Canada (AUCC) and Canadian International Development Agency (CIDA): Tier 2 CIDA-UPCD Project.

Foeniculum vulgare Mill., (fennel), is grown commercially in Tasmania as an essential oil crop. Although oil is produced throughout the plant, approximately 95% is located in the fruits and fruit set directly influences oil yield. In Tasmania commercially grown fennel frequently has a percentage fruit set less than 50%. Research was undertaken into factors influencing fruit set, with the objective of improving fruit set, oil yield and economic returns to growers. The project began with an examination of flower morphology and physiology. Particular importance was placed on the fact that fennel is protandrous and therefore self-incompatible through the timing of pollen production and stigma receptivity. A field trial demonstrated that at high planting densities, fennel produces fewer higher order umbels. This reduces the time span of pollen production and reduces the quantity of pollen available for pollination of the flowers developing later in the season. The work incorporated a study of pollen viability and appeared to show that although pollen viability of glasshouse grown plants is often poor, the problem is not carried over into the field. A field trial involving the application of exogenous hormone gave rise to the hypothesis that competition within the fennel canopy causes poor fruit set. This competition could be for a number of growth factors including nutrients or carbon dioxide. The two factors studied in more detail were light intensity and water stress. Trials suggested fennel to be an obligate heliophyte. It has an open canopy as an adaptation to avoid the absorption of light in excess of that which can be utilised in photosynthesis. In the Tasmanian environment this feature is beneficial in allowing penetration of light through the canopy and prevents shading of the lower umbels. However, it makes fennel inefficient with respect to light absorption and thus possibly makes light a limiting factor. Initial experiments on the effect of water stress in fennel showed the stomata to react slowly to decreasing water availability. They remained open despite the plant wilting. Further investigation showed fennel to have a root system capable of tapping water at depth. Fennel is thought to be a phreatophyte. Fennel plants showed the ability to adjust to cycles of decreasing water potential and after a few cycles of water stress, they no longer wilted. Attempts were made to test the theory ttiat the plant adapted to water stress by increasing its osmotic potential but the methods used were inconclusive.

Biotic pollination services are an essential component of agricultural landscapes; approximately three quarters of the world’s crop species use biotic pollen vectors to initiate or enhance fruit and seed production (Roubik 1995, Nabhan & Buchmann 1997, Kenmore & Krell 1998). Biotic pollination services are in decline, necessitating maintenance of either landscape elements required by pollinating species or the development of new ways to enhance currently managed species or potential new ones (Allen-Wardell et al 1998, Heard 1999). In this empirical study I have surveyed the potential pollinators and measured fruit productivity within a tropical horticultural crop (Annona squamosa x A. cherimola cultivar (cu.) ‘Hillary White’: custard apple) across a northern Australian tropical landscape comprised of a matrix of agricultural land and remnant rainforest patches. I tested the relationship between floral visitor species richness and abundance and two variables; distance that a custard apple orchard was located from naturally occurring rainforest and rainfall. I also tested for a relationship between fruit productivity (initiation) and the distance a custard apple crop was located from naturally occurring rainforest. Unfortunately, due to the absence of replication of the variable ‘orchard distance from naturally occurring rainforest’, all conclusions must be seen as relationships between measured floral visitor and fruit production variables and orchard location in the landscape. The mechanism/s driving these patterns could be a number of factors associated with the landscape gradient such as north-south gradient, rainfall decline or distance that the orchard was located from naturally occurring rainforest and it will take further empirical study to qualify the most important ones. For simplicity here I have retained the variable ‘distance from naturally occurring rainforest’ or ‘crop isolation’ in the thesis as it was the variable that determined the selection of sites. I found 19 species of floral visitors (18 beetles and 1 thrip) to female custard apple flowers; 16 of which are potentially new records for custard apple pollination. Species richness and abundance declined exponentially with distance that a crop was located to naturally occurring rainforest indicating that these floral visitors rely, at least in part, on rainforest resources in the landscape. This is some of the first evidence published (see Blanche & Cunningham 2005) of an effect of crop isolation from native habitat (landscape structure) on a pollinator assemblage other than social bees. Fruit productivity showed the same relationship; flowers were pollen limited in all orchards but there was an exponential decline in productivity with crop isolation indicating that pollen limitation was more pronounced in orchards isolated from naturally occurring rainforest. Empirical evidence for an effect of landscape structure on pollinator assemblages and resultant fruit production has also been found in tropical crop species such as Macadamia tetraphylla (Macadamia nut), in southeastern Australia and Coffea arabica (Coffee) in Central Sulawesi, Indonesia (Heard & Exley 1994, Klein et al 2003). I propose from this evidence that the configuration of landscape elements, such as remnant native rainforest, across an agricultural landscape must be considered in proposals to expand crop areas. Ignoring these elements including threshold distances between pollinator ‘sources’ and crop plants will be detrimental and costly to growers and ultimately may jeopardise the sustainability of agricultural crops. I have also shown in this research that current hand-pollination practises essential to custard apple growers for producing a viable crop may not be ideal. Custard apple growers’ hand-pollinate female custard apple flowers using pollen sourced from either ‘Hillary White’ or ‘African Pride’ cultivar trees. I found that flowers hand-pollinated using cu. ‘African Pride’ produced larger and more symmetrical fruit (better fruit quality) than those hand-pollinated using cu. ‘Hillary White’. These parameters of a fruit are important to growers because larger and more symmetrical fruit are more valuable on the market. The difference in fruit quality was not associated with a decline in fruit quantity in flowers pollinated using cu. ‘African Pride’. Hand-pollination is a incredibly time consuming practise and any progression in traditional hand-pollination techniques that improves fruit production either through an increase in fruit quantity or quality is likely to be embraced by custard apple growers.

Biotic pollination services are an essential component of agricultural landscapes; approximately three quarters of the world’s crop species use biotic pollen vectors to initiate or enhance fruit and seed production (Roubik 1995, Nabhan & Buchmann 1997, Kenmore & Krell 1998). Biotic pollination services are in decline, necessitating maintenance of either landscape elements required by pollinating species or the development of new ways to enhance currently managed species or potential new ones (Allen-Wardell et al 1998, Heard 1999). In this empirical study I have surveyed the potential pollinators and measured fruit productivity within a tropical horticultural crop (Annona squamosa x A. cherimola cultivar (cu.) ‘Hillary White’: custard apple) across a northern Australian tropical landscape comprised of a matrix of agricultural land and remnant rainforest patches. I tested the relationship between floral visitor species richness and abundance and two variables; distance that a custard apple orchard was located from naturally occurring rainforest and rainfall. I also tested for a relationship between fruit productivity (initiation) and the distance a custard apple crop was located from naturally occurring rainforest. Unfortunately, due to the absence of replication of the variable ‘orchard distance from naturally occurring rainforest’, all conclusions must be seen as relationships between measured floral visitor and fruit production variables and orchard location in the landscape. The mechanism/s driving these patterns could be a number of factors associated with the landscape gradient such as north-south gradient, rainfall decline or distance that the orchard was located from naturally occurring rainforest and it will take further empirical study to qualify the most important ones. For simplicity here I have retained the variable ‘distance from naturally occurring rainforest’ or ‘crop isolation’ in the thesis as it was the variable that determined the selection of sites. I found 19 species of floral visitors (18 beetles and 1 thrip) to female custard apple flowers; 16 of which are potentially new records for custard apple pollination. Species richness and abundance declined exponentially with distance that a crop was located to naturally occurring rainforest indicating that these floral visitors rely, at least in part, on rainforest resources in the landscape. This is some of the first evidence published (see Blanche & Cunningham 2005) of an effect of crop isolation from native habitat (landscape structure) on a pollinator assemblage other than social bees. Fruit productivity showed the same relationship; flowers were pollen limited in all orchards but there was an exponential decline in productivity with crop isolation indicating that pollen limitation was more pronounced in orchards isolated from naturally occurring rainforest. Empirical evidence for an effect of landscape structure on pollinator assemblages and resultant fruit production has also been found in tropical crop species such as Macadamia tetraphylla (Macadamia nut), in southeastern Australia and Coffea arabica (Coffee) in Central Sulawesi, Indonesia (Heard & Exley 1994, Klein et al 2003). I propose from this evidence that the configuration of landscape elements, such as remnant native rainforest, across an agricultural landscape must be considered in proposals to expand crop areas. Ignoring these elements including threshold distances between pollinator ‘sources’ and crop plants will be detrimental and costly to growers and ultimately may jeopardise the sustainability of agricultural crops. I have also shown in this research that current hand-pollination practises essential to custard apple growers for producing a viable crop may not be ideal. Custard apple growers’ hand-pollinate female custard apple flowers using pollen sourced from either ‘Hillary White’ or ‘African Pride’ cultivar trees. I found that flowers hand-pollinated using cu. ‘African Pride’ produced larger and more symmetrical fruit (better fruit quality) than those hand-pollinated using cu. ‘Hillary White’. These parameters of a fruit are important to growers because larger and more symmetrical fruit are more valuable on the market. The difference in fruit quality was not associated with a decline in fruit quantity in flowers pollinated using cu. ‘African Pride’. Hand-pollination is a incredibly time consuming practise and any progression in traditional hand-pollination techniques that improves fruit production either through an increase in fruit quantity or quality is likely to be embraced by custard apple growers.