Academic literature on the topic 'Seedling rescue'

Seedlessness is one of the most desirable traits for table and raisin grapes. Stenospermocarpic cultivars are desirable because they have large berries with superior quality. Embryo rescue techniques have been widely used to get progeny seedling populations from crosses using seedless mother plants. Selection of the female parent, sampling time, and the growth medium are the most crucial to the success of this technique. This study investigated the effect of best sampling time and media composition on embryo rescue efficiency in a cold-hardy hybrid grape breeding program. We sampled ovules 5 to 9 weeks after flowering, and we tested four media compositions. The greatest percentages of embryo germination and normal seedlings were obtained when ovules were harvest at 8 weeks after flowering, indicating that it is suitable to harvest ovules at veraison, when the extraction of ovules is easier as a result of softer berry flesh. For the media composition experiment, all ovules were harvested at 8 weeks after flowering. Nitsch & Nitsch culture medium had very low germination, and the resulting seedlings performed the lowest compared with the other treatments. Lloyd & McCown Woody Plant Basal Medium (WPM) increased the number of embryos germinated significantly, and a number of normal seedlings and plantlets developed. Although there was no significant difference among the other three media containing WPM supplemented with different doses of plant regulators, the WPM Plus medium [with cytokinin (6-benzlaminopurine), indole-3-butyric acid, gibberellin, and casein hydrolysate] promoted the greatest percentage of established plants (46.98%). Therefore, the 8-weeks-after-flowering harvest time and the WPM Plus medium were selected for use in the embryo rescue protocol at the University of Minnesota grape breeding program.

O objetivo deste trabalho foi avaliar o efeito do tamanho da planta resgatada e dos níveis de redução foliar na sobrevivência, crescimento e emissão de folhas em mudas de arnica obtidas via resgate em um remanescente de campo rupestre. Foram resgatados 240 indivíduos, os quais foram divididos em duas classes de altura (Classe I – 2,5 a 20 cm e Classe II – 25 a 55 cm) e submetidos a três intensidades de redução foliar (0%, 50% e 100%). As medições de altura, diâmetro e emissão de novas folhas foram realizadas em nove tempos (0, 15, 30, 45, 60, 75, 90, 105 e 120 dias) e a avaliação da sobrevivência aos 120 dias. A taxa média de sobrevivência foi de 49,2%, sendo maior na Classe I e não apresentando diferença estatística quanto aos três tipos de redução foliar. A emissão de folhas foi maior nos indivíduos que sofreram redução foliar, observando-se uma diminuição ao longo do tempo, ao contrário das mudas com 0% de redução, que tiveram um crescimento linear. Portanto, é aconselhável que o resgate de mudas de arnica seja realizado para plantas com tamanho entre 2,5 e 20 cm, sem necessidade de redução foliar.AbstractEvaluation of the arnica plant rescue as an alternative to conservation and restoration of campo rupestre ecosystems. The objective of this research was to evaluate the effect of rescued plant size and levels of reduction in leaf survival, growth, and insertion of leaves in seedlings of Arnica obtained via salvage in a remnant of Campo Rupestre. We rescued 240 individuals and these were divided into two classes’ height (Class I - 2.5 to 20 cm and Class II - 25 - 55 cm) and subjected to three levels of reduction leaf (0%, 50% and 100%). The measurements of height and diameter and new leaves emission were collected at nine times (0, 15, 30, 45, 60, 75, 90, 105 and 120), and evaluation of survival at 120 days. The average survival rate was 49.2%, higher in Class I and had no significant difference regarding the three types of leaf reduction. The emission sheet was higher in subjects experiencing a leaf reduction observing a decrease over time, unlike the seedling with 0% reduction, which increased linearly. Therefore, it is advisable a size between 2.5 and 20 cm for the rescue of arnica seedling plant, without leaf reduction. Keywords: Lychnophora pohlii; seedlings production; leaf reduction; height class.

Twelve-week-old Malus seedlings were induced to cold harden by exposure to low temperature and freezing environments. The effectiveness of induced acclimation by exposure to stimuli such as low temperature (3 to 5 °C), frequency of exposure to freezing temperatures (-3 °C), storage time before and after induction and the effects of different screening temperatures (-20, -30, and -40 °C) were investigated with seedlings grown in a greenhouse from open-pollinated `Golden Delicious' apple (Malus pumila (Mill.), `Antonovka' apple (M. baccata (L.) Borkh. × (M. pumila) and `Rescue' apple (M. baccata) × (M. pumila). Differentiation of the seedling populations with respect to cold hardiness was not achieved until after acclimation at cool temperatures (3 to 5 °C) for 6 weeks. Further population differentiation was achieved by exposure to one or more frosts (-3 °C). Once the acclimation response had been initiated the seedlings could be held for up to 11 days, under the same conditions, with no significant decrease in hardiness. Hardiness levels of acclimated and nonacclimated open pollinated seedlings coincided with known inherent hardiness responses for all three maternal cultivars evaluated. A binomial form of regrowth data collection, percent seedling survival, was determined to be the most efficient and most precise measure of evaluation. Induction of cold hardiness in very young seedlings and the use of a controlled freeze testing protocol should facilitate rapid screening of large progenies and improve the rate of progress in breeding for cold hardiness.

Abstract In flowering plants, repression of the seed maturation program is essential for the transition from the seed to the vegetative phase, but the underlying mechanisms remain poorly understood. The B3-domain protein VIVIPAROUS1/ABSCISIC ACID-INSENSITIVE3-LIKE 1 (VAL1) is involved in repressing the seed maturation program. Here we uncovered a molecular network triggered by the plant hormone brassinosteroid (BR) that inhibits the seed maturation program during the seed-to-seedling transition in Arabidopsis (Arabidopsis thaliana). val1-2 mutant seedlings treated with a BR biosynthesis inhibitor form embryonic structures, whereas BR signaling gain-of-function mutations rescue the embryonic structure trait. Furthermore, the BR-activated transcription factors BRI1-EMS-SUPPRESSOR 1 and BRASSINAZOLE-RESISTANT 1 bind directly to the promoter of AGAMOUS-LIKE15 (AGL15), which encodes a transcription factor involved in activating the seed maturation program, and suppress its expression. Genetic analysis indicated that BR signaling is epistatic to AGL15 and represses the seed maturation program by downregulating AGL15. Finally, we showed that the BR-mediated pathway functions synergistically with the VAL1/2-mediated pathway to ensure the full repression of the seed maturation program. Together, our work uncovered a mechanism underlying the suppression of the seed maturation program, shedding light on how BR promotes seedling growth.

A tissue culture protocol was developed that increased the germination percentage and decreased the lag time to germination for strawberry (Fragaria x ananassa Duch.) achenes. This technique involved cutting surface-sterilized achenes across the embryo axis then placing the shoot apex/radicle-containing sections on semisolid Murashige and Skoog medium lacking hormones. Cut achenes began germinating 5 days after culture and achieved maximum germination (97% to 100%) in less than 2 weeks, compared to whole achenes, which began to germinate 7 to 10 days after sowing and required more than 7 weeks for maximum germination (<50%). Enhanced germination of cut achenes was a general phenomenon since achenes from 231 hybrid crosses responded similarly. Following placement on culture medium, cut achenes could be stored up to 8 weeks at 4C then removed to 27C, where germination and seedling development occurred at percentages and rates comparable to freshly cut achenes. Achenes did not require stratification before cutting to exhibit increased germination. Nearly 100% of the achenes from freshly harvested red-ripe, pink and white strawberries germinated after cutting and culture, although cut achenes from white and pink berries germinated more slowly than those from red-ripe berries. Achenes from green berries, whether whole or cut, did not germinate. This method of “embryo rescue” could be used to generate more seedlings from poorly germinating hybrid crosses, would considerably decrease the time from sowing to seedling production compared to traditional means, and would produce seedlings of uniform age for subsequent field evaluation.

In a breeding program aimed at developing new seedless citrus cultivars, crosses were conducted between Silverhill satsuma and Imperial mandarin as seed parents, and sweet orange and pummelo cultivars as pollen parents. Poncirus trifoliata pollen was also used to provide a morphological marker to compare each seed parent's ability to produce hybrid seedlings. Both Silverhill and Imperial can produce seedless fruits. Methods used to produce and identify hybrids highlighted the relative ease with which either can be used as a seed parent. Imperial mandarin produced more seeds per fruit (mean >8) than Silverhill satsuma (mean <4), thus requiring fewer controlled pollinations to produce desired numbers of hybrids. Germination rates of Imperial-cross seeds were generally greater than for Silverhill-cross seeds. A single seedling emerged from every Imperial-cross seed that germinated, demonstrating the monoembryonic nature of Imperial seeds. All Imperial x P. trifoliata seedlings were hybrids, confirmed by their trifoliate leaves. From this, all seedlings from other Imperial-cross seeds were assumed to be hybrids. By contrast, embryo rescue after in vitro germination demonstrated the polyembryonic nature of the Silverhill-cross seeds. Mean embryo number per Silverhill seed varied from 3.6 to 12.0 between crosses, and from 2 to 30 between seeds within crosses. About 50% of all embryos from Silverhill-cross seeds were rescued and retained for hybrid identification. Silverhill hybrids were identified visually and/or by isozyme banding patterns. Silverhill x pumrnelo hybrids were identified or confirmed using glutamate oxaloacetate transaminase and phosphoglucomutase isozymes. Silverhill x Sweet orange hybrids were identified using isocitrate dehydrogenase, phosphoglucoisomerase or shikimic acid dehydrogenase (SKD) isozymes, although the banding patterns for SKD isozymes were complex and difficult to interpret genetically. Thirty-three Silverhill satsuma hybrids were identified. This represented a hybrid recovery rate of 11.15% compared with >90% for every Imperial-cross combination.

Hybridizations between seedless Vitis vinifera L. genotypes and V. rotundifolia (Michx.) were made specifically to introgress the seedless trait into the disease-resistant background of V. rotundifolia. The seedless, gynoecious P79-101 was hybridized with three V. rotundifolia parents, producing a total of 102 ovules. From these ovules, 44 embryos developed, producing 20 plants. Isozyme analyses and morphological traits confirmed that 19 of the plants were hybrids. Sixteen were planted in an experimental vineyard at California State Univ. Fresno. One seedling, C41-5, produced seedless fruit that appeared to be stenospermocarpic based on fruit and aborted seed size. Fruit weight was slightly less than that of `Thompson Seedless' (stenospermocarpic) and at least twice that of parthenocarpic fruit of `Black Corinth' and C41-7, a seeded hybrid with many parthenocarpic fruit. Aborted seeds of C41-5 were larger than, but not significantly different from, those of `Thompson Seedless', while parthenocarpic fruit from `Black Corinth' and C41-7 had aborted seeds that were smaller than those of C41-5. Seed weight of C41-7 averaged almost 10 times that of aborted C41-5 seeds. This is the first report of a stenospermocarpic, seedless hybrid of V. vinifera × V. rotundifolia.

In the breeding of early maturing peach and nectarine cultivars, the use of embryo rescue techniques is invaluable since the embryos of these materials are not mature by the time the fruit is mature. Thus the seed does not germinate under normal stratification/germination procedures. Peach embryos between 3 and 6 mm in length were cultured in ovule on WPM under treatments that varied in sucrose levels (4% and 6%),the use of vitamins (casein hydrosylate, ascorbic acid, and panthotenic acid) and hormones (BAP and GA3), and the duration of the treatment (7, 14, 21, and 28 days). A five-seed sample was measured for length, fresh weight, and dry weight before and after treatment. The treated embryos were then cultured in a embryo rescue media (WPM, 3% sucrose) at 5 °C for 45 days in the dark and then brought out to room temperature under lights (12-h day). After 2 to 4 weeks the embryos were rated for germination, size, and root number. Embryo perforation treatment resulted in larger embryos but not in better germination than the smaller unperforated embryos. Among the embryos cultured without perforation, the addition of vitamins and hormones caused the production of plants with more roots and shoots but not necessarily with better survival. Both levels of sucrose worked reasonable well. As the time of in ovule treatment increased, embryo growth and plant survival was enhanced.

Submitted by Claudia Rocha (claudia.rocha@udesc.br) on 2017-12-14T12:51:06Z No. of bitstreams: 1 PGEF17MA079.pdf: 1397765 bytes, checksum: 91a801298986f02dd747c0e0d1d4d09f (MD5)<br>Made available in DSpace on 2017-12-14T12:51:06Z (GMT). No. of bitstreams: 1 PGEF17MA079.pdf: 1397765 bytes, checksum: 91a801298986f02dd747c0e0d1d4d09f (MD5) Previous issue date: 2017-02-17<br>FAPESC<br>Eucalyptus species are widely used in the establishment of industrial forests in Brazil and have been achieving quality and productivity gains through genetic improvement and forest management techniques. Companies use cloning to achieve greater homogeneity and quality of forests. The selection of species is an efficient method to increase the forest productivity, being, the cutting, one of the most used techniques of vegetative propagation for selected trees of the genus Eucalyptus. In this context, the general objective of the study was to select, retrieve and multiply the genetic material of the best species / hybrids of Eucalyptus spp. for the purpose of vegetative propagation techniques. The establishment of Eucalyptus spp. of the study is located in the county of Mafra, SC. The plant was planted in December 1998. The species and hybrids present in the experimental area are E. saligna, E. dunnii, E. pelita, E tereticornis, E. viminallis x saligna, E. grandis x urophila, E. dunnii x grandis, E. robusta x grandis and E. urophila x grandis. For selection of the best species / hybrids, individuals were evaluated for survival, height, diameter at breast height and volume. For the vegetative material rescue experiment, the annealing and semi - casting rescue techniques were applied, the individuals were evaluated according to the number of shoots. For the rooting, the species / hybrids, different concentrations of IBA and the type of substrate were evaluated. The species and the hybrids potencies in relation to the quantitative variables, as well as in the ranking were E. dunnii, E. dunnii x E. grandis and E. viminalis x saligna. Among the vegetative rescue methods tested, the annealing presented better results, annealing presented better results for the species E. saligna, while the semi-basement for the hybrid E. robusta x E. grandis.The best percentage of rooting for the substrate was with the substrate 3. There was no root formation using different concentrations of IBA. The best percentage of rooting for the substrate was with the use of substrate 3. For E. pellita and E. viminalis x saligna hybrids, the highest percentage was obtained with the use of 1500 mg L-1. However, for E. dunnii x grandis it is not necessary to use IBA<br>As espécies do gênero Eucalyptus são amplamente utilizadas no estabelecimento de florestas industriais no Brasil e vêm conquistando ganhos de qualidade e produtividade por meio das técnicas de melhoramento genético e manejo florestal. As empresas usam a clonagem para obter maior homogeneidade e qualidade das florestas. A seleção de espécies é um método eficiente de aumentar a produtividade florestal, sendo, a estaquia, uma das técnicas mais utilizadas de propagação vegetativa para árvores selecionadas do gênero Eucalyptus. Nesse contexto, o objetivo geral do estudo foi selecionar, resgatar e multiplicar o material genético dos melhores de Eucalyptus spp., para fins das técnicas de propagação vegetativa. O povoamento de Eucalyptus spp. do estudo está localizada no município de Mafra, SC. O talhão foi plantado em dezembro de 1998. As espécies e híbridos presentes na área experimental são E. saligna, E. dunnii, E. pelita, E tereticornis, E. viminallis x saligna, E. grandis x urophila, E. dunnii x grandis, E. robusta x grandis e E. urophila x grandis. Para seleção dos melhores, os indivíduos foram avaliados quanto à sobrevivência, altura, diâmetro à altura do peito e volume. Para o experimento de resgate de material vegetativo foram aplicadas as técnicas de resgate anelamento e semianelamento, sendo que os indivíduos foram avaliados de acordo com o número de brotações. Para o enraizamento, foram avaliados diferentes concentrações de AIB e tipo de substrato. As espécie e os híbridos com potencial em relação as variáveis quantitativa foram E. dunnii, E. dunnii x E. grandis, E. viminalis x saligna. Dentre os métodos de resgate vegetativo testados, o anelamento apresentou melhores resultados para a espécie E. saligna, enquanto que o semianelamento para o híbrido E. robusta x E. grandis. A melhor porcentagem de enraizamento quanto ao substrato, foi com a utilização do substrato 3. Não houve formação de raízes utilizando diferentes concentrações de AIB. Para sobrevivência as espécies E. pellita e o híbrido E. viminalis x saligna a maior porcentagem foi obtida com a utilização de 1500 mg L-1, já para E. dunnii x grandis não se faz necessário o uso de AIB

O acúmulo significativo de conhecimento sobre a ecologia de restauração nos últimos anos tem conduzido a mudanças na orientação dos programas de manejo e restauração florestal. A escolha ou criação de um modelo de restauração é um processo em constante aprimoramento, exigindo a necessidade de estudos que não apenas diminuam os custos envolvidos, mas também, que garantam a efetividade do objetivo proposto. Neste sentido, este trabalho testa novas metodologias de restauração visando a obtenção de informações técnicas sobre: A) a expressão do banco de sementes autóctone e alóctone na restauração florestal de diferentes situações de degradação antrópica.; B) o resgate de plântulas e indivíduos de espécies arbustivo-arbóreas regenerantes; C) a eficiência de um modelo de plantio que utiliza conceitos de Preenchimento e Diversidade e; D) a evolução da paisagem. Para análise dos bancos de sementes autóctone e alóctone foram feitos levantamentos da densidade e das espécies arbustivo-arbóreas regeneradas. No resgate de indivíduos de espécies arbustivo-arbóreas regenerantes, as plântulas e indivíduos jovens foram resgatadas em uma floresta e levadas para adapatação em viveiro, onde tiveram seus indivíduos e espécies contabilizados em termos de densidade e sobrevivência. No modelo de plantio estudado, as espécies foram reunidas em grupos de Preenchimento e Diversidade e tiveram a cobertura de copa de cada indivíduo quantificada. A evolução da paisagem foi realizada através de fotointerpretação e principalmente checagem de campo periódica. Os principais resultados dessas metodologias foram: A) As situações identificadas na Fazenda Intermontes apresentaram diferentes expressões de regeneração natural em função do número de indivíduos germinados banco de sementes autóctone. O aproveitamento dessa expressão poderá ser realizado através de metodologias diferenciadas de restauração para cada situação estudada: B) No estudo do Banco de sementes alóctone, a densidade dos indivíduos germinados se foi de 409.334 indivíduos/ha, revelando a possibilidade de uso no programa de restauração. Os indivíduos arbóreos apresentaram na área adubada um acréscimo de 137,3 % em sua altura média em relação aos indivíduos da área não adubada. C) No resgate de plântulas e indivíduos de espécies arbustivo-arbóreas regenerantes, a densidade dos indivíduos foi muito próxima para as duas épocas do ano, sendo 38.700 ind./ha e 37.900 ind./ha, mas com uma diferença significante para os indivíduos sobreviventes que apresentaram 16.500 ind./ha e 26.600 ind./ha para os meses de julho e dezembro de 2002, respectivamente. A técnica de resgate utilizada se mostrou viável uma vez que foi possível alcançar até 70,9% de sobrevivência para os indivíduos resgatados; D) No estudo sobre o modelo de plantio foram amostrados 143 espécies, demonstrando que a função do grupo da diversidade vem sendo mantida e aumentando as chances de efetivação dos processos de sucessão. Os resultados mostraram que o grupo de Preenchimento apresentou-se com uma porcentagem de cobertura significativamente maior que a do grupo de Diversidade, sendo 73,6% e 83,3% para 1,5 e 2,5 anos respectivamente.<br>Significant accumulation of know-how about restoration ecology has been changing forest restoration management programs’ trends during the last years. Choosing or elaborating a restoration model is a process that requires constant improvement and ecological studies that not only reduces the costs involved but also warrants the achievement of the aimed proposal. This study explores new restoration methodologies, searching for technical information about: A) autochthonous and allochthonous seed bank expression on forest restoration at different situations degraded by anthropogenic disturbances; B) seedlings and woody growing individuals rescue; C) efficiency of a planting model based on fulfillment and diversity concept; D) landscape development. The autochthonous and allochthonous seed bank were analyzed through regenerating woody species and density scouting. For the rescue of regenerating woody species, seedling and young individuals were taken from a forest and transferred to a plant nursery for adjustment, where number and species were counted regarding density and survival. In this studied planting model, species were organized and gathered into a fulfillment or diversity group, and each individual had its crown area quantified. Landscape development was analyzed by photointerpretation and specially by periodical field checking. Results from these methodologies showed that: A) Identified degraded situations at Intermontes farm displayed distinguished natural regeneration expression, influenced by the number of germinated seeds of the autochthonous seed bank. Advantage can be taken from these different outcomes by using distinct restoration methodologies for each studied situation. B) For the autochthonous seed bank study, germinated seed density was 409,334 ind./ha, indicating its potential role on restoration programs. Woody individuals at fertilized sites had a medium height enhancement of 137,7% when compared to those at non fertilized sites. C) For seedlings and woody growing individuals rescue, individual density was similar for both seasons (38700ind./ha and 37900ind./ha) but significantly distinct for individual survivor, with values of 16500ind./ha for July and 2600ind./ha for December. Rescue technique turned out to be a viable possibility since it achieved survival of 70,9% for rescued individuals. D) This planting model study registered 143 species, indicating that the diversity group’s role has been maintained and enhances the chance of successional process success. The fulfilling group had a significant higher percentage of crown area than the diversity group, with 73,6% and 83,3% for 1,5 and 2,5 years, respectively.

With the increase of the demand for forest seedlings, both training for business stands and recovery of degraded areas, there is a growing concern with the reduction of costs and the need to follow sustainability standards in the production of seedlings. For this reason, renewable materials have been studied and used for formulation of substrates, and the lump of peach has potential to be used with this purpose, which has the physical structure rigid that do not decomposes with ease and, when triturated, retains particles of various granulometries. The present study had as objectives: I - Evaluate the characteristics peach lump triturated for use as a component of the substrate for plants; II - to investigate the influence of substrates with different proportions of peach lump triturated seedling growth of E. dunnii seeds in the nursery and the performance in the field. Were used different proportions of mixture [100:0%, 80:20%; 60:40%; 40:60%; 20:80%; 0:100% (volume:volume)] from peach lump triturated (C) and commercial substrate (S), composing the group 1 (CxS), and C and peat brown (T), called the group 2 (CxT). It was evaluated the physical, chemical and the content of the macronutrients of mixtures. In the nursery evaluations were made of height (H), collar diameter (DC), H/DC, dry mass carrier, root dry mass, total dry mass, the quality index of Dickson, leaf area, root length and volume, ease of withdrawal of the seedlings in the polyethylene tube, aggregation of roots and photochemical efficiency of photosystem II maximum In the field, it was evaluated the survival, the increment in the growth in height and diameter of the stem base diameters and physiological variables during 240 days. In general, the results obtained allow us to infer that the peach lump triturated presents physical and chemical characteristics suitable for use as a component of substrates, increasing the density wet and dry, the material consisting of aeration and pH, while the total porosity, water holding capacity and the electric conductivity had lower values for the substrates with or with a higher proportion of peach lump triturated. In the production of seedlings of E. dunnii seeds, this material reduced the growth of the same, but can be used as a component of substrate in all the proportions of the mixture with commercial substrate without interfering with their development in the field, but with proportions greater than 20% change has difficulty be removed from the cartridge and less aggregation, reducing the yield of the operations in the field. Mixed with brown peat, it is recommended to use proportions between 15% and 30% of crushed peach kernel allowing better growth of seedlings in the nursery and good performance after planting.<br>Com o aumento da demanda por mudas florestais, tanto para formação de povoamentos comerciais quanto para recuperação de áreas degradadas, houve uma consequente preocupação com a redução dos custos e necessidade de seguir padrões de sustentabilidade na produção de mudas. Para isso, materiais renováveis vêm sendo pesquisados e utilizados para formulação de substratos e o caroço de pêssego possui potencial para ser utilizado com essa finalidade, o qual possui estrutura física rígida que não se decompõe com facilidade e, quando triturado, mantem partículas de diversas granulometrias. O presente estudo teve como objetivos: I Avaliar as características do caroço de pêssego triturado para uso como componente de substrato para plantas; II Investigar a influência de substratos com diferentes proporções de caroço de pêssego triturado no crescimento de mudas de Eucalyptus dunnii no viveiro e o desempenho em campo. Foram utilizadas diferentes proporções de mistura [100:0%, 80:20%; 60:40%; 40:60%; 20:80%; 0:100% (volume:volume)] de caroço de pêssego triturado (C) com substrato comercial a base de composto orgânico (S), compondo o grupo 1 (CxS), e C com turfa marrom (T), denominado grupo 2 (CxT). Avaliaram-se as propriedades físicas, químicas e o teor de macronutrientes das misturas. No viveiro foram realizadas avaliações da altura (H), diâmetro do coleto (DC), relação H/DC, massa seca aérea, massa seca radicular, massa seca total, índice de qualidade de Dickson, área foliar, comprimento e volume radicular, facilidade de retirada das mudas do tubete, agregação das raízes e eficiência fotoquímica máxima do fotossistema II. No campo, avaliou-se a sobrevivência, o incremento no crescimento em altura e em diâmetro do coleto e variáveis fisiológicas durante 240 dias. De maneira geral, os resultados obtidos permitem inferir que o caroço de pêssego triturado apresenta características físicas e químicas adequadas para uso como componente de substratos. Esse material aumenta a densidade úmida e seca, o espaço de aeração e pH, enquanto que reduz a porosidade total, a capacidade de retenção de água e a condutividade elétrica. Na produção de mudas de E. dunnii, esse material reduziu o crescimento das mesmas, mas pode ser utilizado como componente de substrato em todas as proporções de mistura com substrato comercial a base de composto orgânico sem interferir no seu desenvolvimento a campo, porém com proporções superiores a 20% a muda apresenta dificuldade de ser retirada do tubete e menor agregação, reduzindo o rendimento das operações no campo. Em mistura com turfa marrom, recomenda-se utilizar proporções entre 15% e 30% de caroço de pêssego triturado permitindo melhor crescimento das mudas no viveiro e bom desempenho após o plantio.

Bauxite residue (red mud) is an industrial waste bye product of Alumina industry. It is toxic and highly alkaline in nature having heavy metals. Its disposal is the paramount environmental issue in Alumina industry. In the present study, bioremediation of red mud was carried out through cyanobacteria amendments and plantation. Two cyanobacterial species (viz. Phormidium and Oscillatoria) were found promising after studying their effect on physico-chemical characteristics of red mud. Seeds of selected tree species (viz. Dalbergia sissoo, Prosopis juliflora, Acacia auriculiformis, Pithecellobium dulce, Cassia siamia) were procured, and a nursery of these tree species was raised. Performances of two cyanobacteria (viz. Phormidium and Oscillatoria sps.) in combinations with PSB and VAM on red mud are very encouraging and hold considerable promise for bioremediation and revegetation of red mud. Inoculated seedlings of P. juliflora, P. dulce, A. auriculiformis, and C. siamia performed well for red mud revegetation.