Journal articles: 'South african sunflower seed'

1

Zazzerini, A., L. Tosi, and P. M. Vicente. "First Report of Root-Knot Nematodes (Meloidogyne spp.) on Sunflowers in Mozambique." Plant Disease 81, no. 11 (November 1997): 1333. http://dx.doi.org/10.1094/pdis.1997.81.11.1333e.

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Sunflower (Helianthus annuus L.) recently was reintroduced to Mozambique because of renewed interest in oil-seed production for domestic consumption. In April 1997, disease surveys were carried out in two fields in southern Mozambique (Maputo region). Several plants of Pan 735, a South African cultivar, showed yellowing of the leaves and stunting. These plants wilted during the day but recovered their turgidity at night. Diseased plants were easily pulled from the soil due to almost complete destruction of the root system. Numerous galls were found on affected roots, compared with healthy plants. Meloidogyne javanica (Treub) Chitwood and M. incognita (Kofoid & White) Chitwood were identified by M. Di Vito (personal communication) based on 20 female perineal patterns observed with a light microscope. M. incognita was more prevalent than M. javanica. Also observed were Alternaria helianthi (Hansf.) Tubaki & Nishihara and Sclerotium bataticola Taub. Root-knot nematodes (Meloidogyne spp.), common on sunflower, cause severe damage and reduce both seed yield and seed oil content (1). These two nematode species have also been observed on sunflower in other African countries (Zambia, South Africa, Egypt) but this is the first report of root-knot nematode on sunflower in Mozambique. Reference: (1) M. Di Vito et al. Nematol. Medit. 24:109, 1996.

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Hickert, Sebastian, Lena Hermes, Lucas Maciel Mauriz Marques, Christine Focke, Benedikt Cramer, Norberto Peporine Lopes, Bradley Flett, and Hans-Ulrich Humpf. "Alternaria toxins in South African sunflower seeds: cooperative study." Mycotoxin Research 33, no. 4 (July 28, 2017): 309–21. http://dx.doi.org/10.1007/s12550-017-0290-1.

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Van Schalkwyk, HP, HD Van Schalkwyk, ZG Alemu, PR Taljaard, and A. Obi. "The primary demand for oilseeds in South Africa: An error correction linear approximated and almost ideal demand system (ECM-LA/AIDS)." South African Journal of Economic and Management Sciences 8, no. 1 (January 13, 2015): 117–26. http://dx.doi.org/10.4102/sajems.v8i1.1288.

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The paper presents the results of a study that estimated the demand relations for primary oilseeds in South Africa. The Error Correction version of Linear Approximated Almost Ideal Demand System (LA/AIDS)(ECM-LA/AIDS) were estimated. Time series data for the period 1971-2002 were analysed. Prior tests stablished weak searability between four oilseeds (sunflower seed, soybeans, groundnuts and cotton seed), indicating that these oilseeds should be modelled together. The results suggest that the demand for oilseeds is negatively influenced by own price, which is consistent with economic theory, while positive long-term expenditure elasticities suggest that some oilseeds, notably sunflower seed and cotton seed, are luxury commodities in South Africa.

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Viljoen, A., P. S. van Wyk, and W. J. Jooste. "Occurrence of the White Rust Pathogen, Albugo tragopogonis, in Seed of Sunflower." Plant Disease 83, no. 1 (January 1999): 77. http://dx.doi.org/10.1094/pdis.1999.83.1.77a.

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White rust of sunflower (Helianthus annuus L.), caused by Albugo tragopogonis (Pers.) S. F. Gray, appeared in South African fields not previously planted to sunflower. Spread to these fields from infested fields was unlikely, as some of the newly affected fields were planted out of season and were more than 300 km away from other sunflower production fields. Several reports of this nature led us to investigate the possibility of seed transmission of the causal organism. Extensive colonization of sunflower heads by A. tragopogonis was observed in field trials and breeding nurseries. Head infections consisted of two distinct lesion types. White rust pustules, typical of those formed on abaxial sides of leaves, were recognized on abaxial sides of involucral bracts. Grayish, localized lesions containing dark-colored oospores of the fungus, similar to those formed on stems and petioles (1), were produced in sub-epidermal tissue and extended 3 to 5 mm deep into receptacles. Colonization of seeds was found in only a few lines. Oospores were produced in the pericarps and testae of seeds. No oospores or hyphae, however, were observed in the embryo. This is the first report of A. tragopogonis being seed-borne. Since the incidence of seed infection is low, spread of disease to infested fields is expected to be insignificant. Of more concern, however, is the possible long-range dissemination of the fungus by means of infected seed into regions or countries where the disease has not been previously reported. Reference: (1) P. S. Van Wyk et al. Helia 18:83, 1995.

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Viljoen, A., P. S. van Wyk, D. C. Nowell, and T. J. Gulya. "Occurrence of Downy Mildew on Sunflower in South Africa." Plant Disease 81, no. 1 (January 1997): 111. http://dx.doi.org/10.1094/pdis.1997.81.1.111c.

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Downy mildew, caused by Plasmopara halstedii (Farl.) Berl. & De Toni in Sacc., is an economically important disease of sunflower (Helianthus annuus L.) in Europe and the United States (1). The disease was first noticed in South Africa in a commercial field near Standerton and in a seed production field near Kroonstad during the 1993 to 1994 planting season. During the 1995 to 1996 season, downy mildew was found in experimental hybrids near Heilbron, and in commercial fields near Heil-bron, Marikana, and Potchefstroom. At Heilbron, five hybrids were infected with P. halstedii, whereas three others showed symptoms of downy mildew at Potchefstroom and Marikana. All commercially cultivated hybrids have been developed in South Africa. Disease incidence in all the fields was low, with less than 1% of plants affected by the disease. Diseased plants were dwarfed and displayed veinal chlorosis of leaves typically associated with downy mildew of sunflower. White fungal growth commonly occurred on lower leaf surfaces. Sunflower seedlings inoculated with P. halstedii produced symptoms characteristic of downy mildew. The occurrence of the disease in many geographic areas and on various hybrids in South Africa suggests that the fungus is well established. Recent outbreaks can be attributed to the cool, wet, climatic conditions of the 1993 to 1994 and 1995 to 1996 seasons. The susceptibility of local hybrids suggests that downy mildew is a potentially dangerous disease of sunflower in South Africa. Reference: (1) J. F. Miller and T. J. Gulya. Crop Sci. 27:210, 1987.

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Phukubje, M. P., and M. B. Moholwa. "Testing for weak-form efficiency in South African futures markets for wheat and sunflower seeds." Agrekon 45, no. 2 (June 2006): 198–213. http://dx.doi.org/10.1080/03031853.2006.9523743.

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7

Chigeza, Godfree, Kingstone Mashingaidze, and Paul Shanahan. "Seed yield and associated trait improvements in sunflower cultivars over four decades of breeding in South Africa." Field Crops Research 130 (March 2012): 46–56. http://dx.doi.org/10.1016/j.fcr.2012.01.015.

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8

Adeleke, Bartholomew, Ayansina Ayangbenro, and Olubukola Babalola. "Genomic Analysis of Endophytic Bacillus cereus T4S and Its Plant Growth-Promoting Traits." Plants 10, no. 9 (August 26, 2021): 1776. http://dx.doi.org/10.3390/plants10091776.

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Insights into plant endophytic microbes and their exploration in agriculture have provided opportunities for sustainable plant health and food safety. Notable endophytic Bacillus species with plant growth-promoting traits have been documented; nevertheless, information on genome analysis of B. cereus associated with the sunflower in South Africa has not been studied. Therefore, we present whole-genome sequence of agriculturally important B. cereus strain T4S isolated from sunflower plants. The NextSeq Illumina sequencing yielded 7,255,762 bp sequence reads, 151 bp average read length, 5,945,881 bp genome size, 56 tRNA, 63 rRNA, and G + C content of 34.8%. The phylogeny analysis of strain T4S was similar to B. cereus NJ-W. Secondary metabolites, such as petrobactin, bacillibactin, bacitracin, molybdenum factor, zwittermicin, and fengycin underlining bacterial biocontrol efficacy against phytopathogens were found in the T4S genome. The predicted novel genes in the bacterial genome mediating the complex metabolic pathways can provide a genetic basis in understanding endosphere biology and their multiple functions thereof in crop improvement. Interestingly, seed and root inoculation with strain T4S contributed to sunflower yield under greenhouse experiments. Hence, the detection of notable genes specific for plant growth promotion as validated under in vitro screening, promisingly, suggests the relevance of strain T4S in agricultural biotechnology.

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9

Potter, TD, and PI McLoud. "Evaluation of sunflower cultivars in South Australia." Australian Journal of Experimental Agriculture 25, no. 1 (1985): 178. http://dx.doi.org/10.1071/ea9850178.

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Seed yields and oil contents were determined for several sunflower cultivars grown in the south-east of South Australia over a range of environments which included different locations and years. Data were analysed by modified joint regression techniques. Each cultivar was included in at least four experiments to allow analysis by modified joint regression. The highest seed yields were produced by Hysun 3 1, Sungold, Suncross 52, Sunking and Hysun 30, which produced 16.4, 15.4, 14.7, 12.4 and 7.4% more seed, respectively, than Peredovik. Seeds with the highest oil contents were produced by Suncross 52 (48.6% w/w) and Hysun 31 (48.3%); Hysun 10 and Stepniak produced seeds with the lowest oil content (43.7 %) . Later flowering cultivars had significantly higher seed yields and oil contents than earlier flowering cultivars, indicating that they were better adapted to the environment. For every day that flowering of a cultivar was later than that of Perodovik, mean seed yield increased by 56.6 kg/ha and oil content by 0.4%.

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10

van Niekerk, JH. "Loss of sunflower seeds to columbids in South Africa: economic implications and control measures." Ostrich 80, no. 1 (April 2009): 47–52. http://dx.doi.org/10.2989/ostrich.2009.80.1.7.765.

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11

Van der Walt, W. J. "Changing Face of South African Seed Trade." Journal of New Seeds 1, no. 1 (April 29, 1999): 81–97. http://dx.doi.org/10.1300/j153v01n01_06.

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12

Nicolaides, C. P., J. H. Opperman, M. S. Scurrell, and W. W. Focke. "Metathesis of fatty esters derived from South African sunflower oil." Journal of the American Oil Chemists' Society 67, no. 6 (June 1990): 362–63. http://dx.doi.org/10.1007/bf02539690.

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13

Brewer, Gary J., and Gene Schmidt. "Trap cropping to manage the red sunflower seed weevil in oilseed sunflower." American Journal of Alternative Agriculture 10, no. 4 (December 1995): 184–87. http://dx.doi.org/10.1017/s0889189300006469.

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AbstractThe red sunflower seed weevil,Smicronyx fulvusLeConte, is a major pest of sunflower in North and South Dakota and Minnesota. Typically, insecticides are used to reduce oviposition and prevent economically damaging larval populations from developing. In a test of a reduced-pesticide alternative, we planted early maturing sunflower in the margins around commercial fields of oilseed sunflower. The margins flowered earlier than the field interiors and acted as a trap for the red sunflower seed weevil. They were treated with an insecticide while the trap rows were blooming and before the field interior began to flower. Conventional fields entirely treated with insecticide served as checks. We compared the trap and check fields with regard to yield, the fraction of larval-damaged seeds, and economic costs (insect damage and the cost of insecticide materials and application). Yield and larval damage of seeds were comparable between check and trap fields. However, the economic costs of weevil control in the check fields was greater than in the trap fields. Trap cropping is a recommended strategy for the red sunflower seed weevil, especially where economically damaging populations of the weevil are expected.

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14

Van Der Walt, Wynand J. "A Review of the South African Seed Industry." Journal of New Seeds 4, no. 3 (June 2002): 57–70. http://dx.doi.org/10.1300/j153v04n03_05.

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15

Hamman, B., G. Koning, and H. A. van de Venter. "Germination of South African soya bean seed lots." South African Journal of Plant and Soil 13, no. 1 (January 1996): 5–8. http://dx.doi.org/10.1080/02571862.1996.10634366.

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16

Holmes, Patricia M., and Rosemary J. Newton. "Patterns of seed persistence in South African fynbos." Plant Ecology (formerly Vegetatio) 172, no. 1 (May 2004): 143–58. http://dx.doi.org/10.1023/b:vege.0000026035.73496.34.

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17

Seiler, Gerald J., Christopher G. Misar, Thomas J. Gulya, William R. Underwood, Bradley C. Flett, Michelle A. Gilley, and Samuel G. Markell. "Identification of Novel Sources of Resistance to Sclerotinia Basal Stalk Rot in South African Sunflower Germplasm." Plant Health Progress 18, no. 2 (January 1, 2017): 87–90. http://dx.doi.org/10.1094/php-01-17-0007-rs.

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Sclerotinia basal stalk rot (BSR) is a serious fungal disease that reduces yield of global sunflower (Helianthus annuus L.) production. Because limited chemical and biological controls of BSR are available and the present-day hybrids lack sufficient resistance, identification of new sources of resistance is needed to manage the disease in the future. A total of 59 cultivated oilseed sunflower accessions from the Agricultural Research Council, Grain Crops Institute, Potchefstroom, South Africa sunflower collection were evaluated for resistance to BSR in artificially inoculated field trials. Nine accessions from the South African sunflower collection were identified with a disease incidence less than or equal to the moderately resistant sunflower oilseed hybrid. These lines can be used in breeding programs to introgress the genes for resistance to Sclerotinia BSR into other adapted lines, providing a more efficient, durable, and environmentally friendly host plant resistance.

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18

Allemann, J., and G. M. Ceronio. "Screening of South African sunflower (Helianthus annuusL.) cultivars for alachlor sensitivity." South African Journal of Plant and Soil 24, no. 1 (January 2007): 16–21. http://dx.doi.org/10.1080/02571862.2007.10634775.

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Allemann, J., and G. M. Ceronio. "Effect of microencapsulated alachlor on South African sunflower (Helianthus annuusL.) cultivars." South African Journal of Plant and Soil 26, no. 2 (January 2009): 110–18. http://dx.doi.org/10.1080/02571862.2009.10639942.

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20

Ogundeji, Abiodun, Andre Jooste, and D. Uchezuba. "Econometric estimation of Armington elasticities for selected agricultural products in South Africa." South African Journal of Economic and Management Sciences 13, no. 2 (December 3, 2010): 123–34. http://dx.doi.org/10.4102/sajems.v13i2.41.

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Price transmission behaviour is used to model the impacts of different trade regimes; if this behaviour is not modelled correctly, the trade impacts can be either under- or overestimated. Due to the lack of elasticities of substitution pertaining to selected imported and domestically produced agricultural products in South Africa, ‘Armington’ elasticities, using quarterly data from 1995-2006 and three different models, based on the time series properties of the data, are estimated in this paper. Considering the long-run elasticity results, soyabeans (whether broken or not) and meat of bovine animals (frozen) are the most sensitive import products, followed by maize, meat of bovine animals (fresh or chilled), sunflower seeds, and wheat and meslin. Regarding the short-run elasticity, soyabeans are the most sensitive import product, followed by meat of bovine animals (fresh or chilled); meat of swine (fresh, chilled or frozen) is the least sensitive import product.

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Shafiullah, S. Asad, M. A. Rana Baitullah, and A. S. Khan Baitullah. "EFFECT OF ROW DIRECTIONS ON YIELD AND YIELD COMPONENTS OF SUNFLOWER (Helianthus annuus L.) / EFECTO DE LA DIRECCION DE EXTENSION DE HILERA SOBRE EL RENDIMIENTO Y LOS COMPONENTES DEL RENDIMIENTO DE GIRASOL (Helianthus annuus L.) / EFFET DU SENS DES RANGÉES SUR LE RENDEMENT ET LES COMPOSANTES DU RENDEMENT CHEZ LE TOURNESOL (Helianthus annuus L.)." HELIA 24, no. 34 (July 2001): 137–44. http://dx.doi.org/10.1515/helia.2001.24.34.137.

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SUMMARY Effect of different row directions on yield and yield components of sunflower (Helianthus annuus L.) was studied in a field experiment at National Agricultural Research Center, Islamabad, Pakistan, during spring 1991 and 1992. Four row directions, i.e., north-south (NS), east-west (EW), north eastsouth west (NESW) and north west-south east (NWSE) had very little effect on seed yield and other agronomic characters of sunflower. The differences in the mean plant height, head diameter, seed yield, 100-achene weight and fatty acid profile were statistically non-significant. Trends were similar in both years. As an average of the two years, although statistically non-significant, the highest seed yield of 3065 kg/ha was obtained from north east-south west (NESW) row direction and the lowest yield of 2624 kg/ha from east-west (EW) row direction. The most pronounced effect of row direction was noted on seed moisture content. As an average of the two years, the maximum seed moisture content at harvest (21.4%) was obtained from east-west (EW) row direction and the minimum (14.6%) from north-south (NS) row direction. NESW row direction also gave significantly lower moisture content (15.1%) than EW (21.4%) and NWSE (18.1%) row directions. Therefore, using north-south and NESW row directions would help the crop to dry more quickly before harvest and reduce post harvest costs and losses. Seed production fields that require examination of sunflower heads to detect pollen production should be planted in NS rows for efficient roguing to maintain genetic purity. For research plots, EW rows with plot labels on the east end are often preferred, because it is easier to evaluate most plots when all heads face the viewer.

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Opperman, M., AJS Benadé, CF Abrecht, and LL Matsheka. "South African seed oils are safe for human consumption." South African Journal of Clinical Nutrition 29, no. 1 (January 2, 2016): 7–11. http://dx.doi.org/10.1080/16070658.2016.1215879.

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23

Prasifka, Jarrad R., and Brent S. Hulke. "Capitate Glandular Trichomes Fail to Provide Significant Resistance to Banded Sunflower Moth (Lepidoptera: Tortricidae)." Environmental Entomology 49, no. 2 (January 21, 2020): 444–48. http://dx.doi.org/10.1093/ee/nvaa002.

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Abstract Extracts from capitate glandular trichomes (CGT) of wild and cultivated sunflowers, Helianthus spp., have repellent or toxic effects on sunflower specialists and generalist herbivores less closely associated with sunflower. Though CGT have been primarily examined for their potential to provide partial resistance to the sunflower moth, Homoeosoma electellum Hulst (Lepidoptera: Pyralidae), a floret- and seed-feeding pest, the banded sunflower moth (Cochylis hospes Walsingham [Lepidoptera: Tortricidae]) is a similar species more common in the primary sunflower-producing states of North Dakota and South Dakota. Replicated field trials using partially inbred lines with low or high CGT densities were used to evaluate possible reductions to seed damage by C. hospes larvae in 2016–2017. Results failed to support the idea that CGT are a useful defense against larvae of C. hospes; the putative plant defense of high trichome density corresponded to slightly more, rather than less, insect damage. A test of a secondary explanation, that strength of sunflower hulls could help determine patterns of seed damage among tested lines, produced similarly negative results. Though timing of bloom differed between groups of most- and least-damaged lines, prior research and pheromone-trapping data suggest differences in plant maturity also cannot adequately explain the observed results. While the specific mechanisms remain unclear, significant differences in susceptibility to C. hospes exist for cultivated sunflower and limit losses from this primary insect pest.

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Chinnamuthu, C., A. Sivamurugan, and A. Balasubramanian. "A NEW CHEMICAL BRASSINOLIDE IN COMBINATION WITH FERTILIZER LEVELS TO IMPROVE THE SEED SETTING PERCENTAGE IN SUNFLOWER." Acta Agronomica Hungarica 48, no. 2 (September 1, 2000): 171–76. http://dx.doi.org/10.1556/aagr.48.2000.2.7.

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Poor seed set and filling is one of the most common problems encountered in sunflower cultivation. The yield of sunflower could be increased to a considerable extent by using brassinolide, a plant growth promoting substance, isolated from the pollen of rape, which prevents the formation of empty achenes, thus increasing the number of filled seeds. Field experiments were carried out at Tamil Nadu Agricultural University, Coimbatore, India during the summer (March–May) and South West Monsoon (June– September) seasons of 1997 to study the effect of brassinolide and NPK levels on the yield and yield attributes of sunflower. The experiments were laid out in a split plot design. The main plots were treated with five levels of fertilizer (N:P:K), namely 40:20:20, 50:25:25, 60:30:30, 70:35:35 and 80:40:40 kg ha -1, while the subplots consisted of seed setting treatments: hand pollination, 0.2% borax + 2% diammonium phosphate spray and 1 ppm brassinolide spray at the ray floret opening stage, together with a control. Yield attributes: head diameter, number of seeds head –1, seed filling percentage and 100 seed weight, were significantly influenced by NPK levels. Among the seed setting treatments, brassinsolide 1 ppm spray at the ray floret opening stage was found to be superior in enhancing the seed setting percentage. The application of N:P:K at 80:40:40 kg ha –1 was found to be optimum for higher seed yield in sunflower.

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Hlatshwayo, SI, AT Modi, S. Hlahla, M. Ngidi, and T. Mabhaudhi. "Usefulness of seed systems for reviving smallholder agriculture: a South African perspective." African Journal of Food, Agriculture, Nutrition and Development 21, no. 02 (March 24, 2021): 17581–603. http://dx.doi.org/10.18697/ajfand.97.19480.

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South Africa is considered a food-secure nation; however, food insecurity is still a major challenge for many poor rural households that rely on cash incomes and government grants for survival. Furthermore, these grants are not always adequate to meet households’ basic needs and fail to provide them with the food required for food and nutrition security. Some of these households rely on agriculture to supplement their food needs, and an important aspect of this agricultural production is the seed system. Smallholder farmers in rural areas rely on informal seed systems, and use traditional knowledge and methods to produce, harvest, store, and sell their produce. This research combined quantitative and qualitative methods to assess the role of informal seed systems in promoting food production in rural smallholder agricultural households in South Africa. The narrative review showed reword that while smallholder farmers acquire seed from informal seed systems, they face numerous challenges that affect their production activities. These challenges include poor seed quality and assessment, poor storage and harvesting facilities, which limit proper seed production and affect crop yield and marketing. Due to these challenges, the ability of rural smallholder farmers to access mainstream markets is limited and as a result, they are confined to local markets that offer lower prices. Moreover, South African policies do not recognize the informal seed system as one of the contributors to food security. This is a major limitation as farmers may not receive the support and assistance they require. Formal recognition and support for informal seed systems would go a long way in improving smallholder farmers’ access to quality seed. This would have ripple effects on their yields and productivity. When properly implemented and given recognition by the government, informal seed systems have the potential to contribute to rural food security and livelihoods.

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Georgescu, Emil, Maria Toader, Alina Maria Ionescu, Lidia Cană, and Luxiţa Râşnoveanu. "Researches Concerning Sunflower Seeds Treatment against Tanymecus Dilaticollis, in Green House Conditions." “Agriculture for Life, Life for Agriculture” Conference Proceedings 1, no. 1 (July 1, 2018): 64–71. http://dx.doi.org/10.2478/alife-2018-0010.

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Abstract In the last years sunflower become one of the most important crops in Romania. The most of the surface cultivated with sunflower from our country is located in south and south-east and, in many cases, sunflower is cultivated after maize. As result the attack of the maize leaf weevil (Tanymecus dilaticollis Gyll) at sunflower plants has increasing. The attack is dangerous when sunflower plants are in first vegetation stages (BBCH 10-BBCH 14). Similar with maize crop, sunflower seeds treatment with neonicotinoids were generalized after 2007. As result of the EU directive 485/2013, no active ingredients remain available for sunflower seeds treatment, against T. dilaticollis, in Romania. The researches from the last years were orientated for finding of the possible alternatives for seed treatments, in eventuality of permanent ban of neonicotinoid insecticides, after 2018. Because of the variability of climatic conditions from the field, during spring period, researches concerning effectiveness testing of sunflower seed treatments, in green house conditions, using high pest pressure is a good method to evaluate influence of the different active ingredients to control T. dilaticollis adults. In this experiment it has tested three doses of cyantraniliprole active ingredient (7.5, 10.0 and 12.5 l/to) and three neonicothinoid active ingredients (imidacloprid, clothianidin, thiamethoxam). Sunflower seeds were placed in plastic pots. After plants emergence the insects were added in pots. At each pot it has added 20 adult insects, collected from the field. Each day, it has recorded insect mortality. At 8 days from the start of the experiment, it has assessed attack intensity of the adult insects on sunflower plants. The attack was evaluated using a scale from 1 (plant not attacked) to 9 (plant complete destroyed). In conditions of high pest pressure (4 insects/plant) the attack intensity of T. dilaticollis at sunflower plants was ranged from 3.35 in case of variant treated with clothianidin and 8.50 in case of untreated plants. Lower attack intensity of the pest at sunflower plants it has registered in case of variants treated with imidacloprid and thiamethoxam (I=3.58 and 3.50). Plants emerged from the untreated seeds were destroyed by the insects, at 8 days from the start of the experiment.

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du Toit, A. P., and L. A. Coetzer. "DIFFERENCE IN POTENTIAL ATTRACTIVENESS TO BEES OF SEVENTEEN SOUTH AFRICAN SUNFLOWER (HELIANTHUS ANNUUS) CULTIVARS." Acta Horticulturae, no. 288 (January 1991): 288–93. http://dx.doi.org/10.17660/actahortic.1991.288.45.

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Calamai, A., A. Masoni, E. Palchetti, C. Grassi, and L. Brilli. "Evaluation of Agronomic Performance and Seed Oil Composition of 15 Sunflower Genotypes in South Madagascar." Agricultural Sciences 09, no. 10 (2018): 1337–53. http://dx.doi.org/10.4236/as.2018.910093.

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Lobachev, Yuriy Viktorovich, Sergey Petrovich Kudryashov, Lyudmila Gennadievna Kurasova, and Yulia Yuryevna Bandurina. "The source material for the selection of decorative sunflower." Agrarian Scientific Journal, no. 4 (April 22, 2020): 28–30. http://dx.doi.org/10.28983/asj.y2020i4pp28-30.

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Seven lines of analogs with different color of leaves were created in sunflower by the backcross method of the recipient line of YuV-28B and gene donors controlling different variations in leaf color. A study of these lines at the Research Institute of Agriculture of the South-East region in 2017–2019, conducted as a competitive variety test, showed that most seed lines did not significantly differ in seed yield from the recipient line YuV-28B except for the L-4 line with olive color of the sheet, in which this indicator was lower than that of the recipient line. They were assessed analogous lines according to the phenological, morphological, crop-forming characteristics, as well as according to the quality of seeds and oil. All analogue lines had 100% shell of seeds and resistance to local races of broomrape and downy mildew. Most of the studied indicators of these lines correspond to the parameters of the source material, so they can be used in the selection of decorative sunflower.

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Smuts, Marius, and Linda Malan. "Perspectives on the use of seed oils in the South African diet." South African Journal of Clinical Nutrition 29, no. 1 (January 2, 2016): 4–6. http://dx.doi.org/10.1080/16070658.2016.1215872.

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Rosenblatt, Paul C., and Catherine Nkosi. "The Seed Is Mine: The Life ofKas Maine, A South African Sharecropper 1894-1985:The Seed Is Mine: The Life ofKas Maine, A South African Sharecropper 1894-1985." Culture Agriculture 25, no. 1 (March 2003): 55–56. http://dx.doi.org/10.1525/cag.2003.25.1.55.

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Cupido, C. N., W. M. M. Eddie, and L. R. Tiedt. "SYSTEMATIC AND ECOLOGICAL SIGNIFICANCE OF SEED COAT MORPHOLOGY IN SOUTH AFRICAN CAMPANULACEAE SENSU STRICTO." Edinburgh Journal of Botany 68, no. 3 (October 18, 2011): 351–71. http://dx.doi.org/10.1017/s0960428611000291.

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The seed coat morphology of 50 species of Campanulaceae sensu stricto, representing all 10 South African genera, was studied by scanning electron microscopy to gauge its usefulness in the diagnosis of genera or to support clades. Possible correlations with life form (annual, herbaceous and woody perennial) and ecological requirements such as fire response, rainfall requirements, bedrock and soil preferences, as well as habitat (e.g. fynbos, strandveld, renosterveld, grassland and karoo), were also investigated. Patterns of variation are described and interpreted as conforming to two seed coat types: reticulate (Type 1) and striate/wavy (Type 2). Type 1 seeds are further divided into eight subtypes. Some general trends emerged; for example, Type 1 seeds occur in all major clades of wahlenbergioids, Type 1A with a smooth coarsely reticulate surface being predominant in fynbos taxa, all of which are woody perennials. Several of the Type 1 seeds, together with Type 2 seeds, also occur in species with wider ecological amplitude, for example in karoo, strandveld or montane grasslands. In Siphocodon there is remarkable disparity in seed type between species. These variations in seed type generally appear to accord with current knowledge of climatic changes and soil evolution during the Tertiary of South Africa, and may be useful indicators of generic emergence and mosaic speciation in the major lineages of wahlenbergioids. However, it was concluded that seed coat types do not correlate closely enough with specific ecological requirements or life forms to be of unequivocal predictive value. Also, apart from Merciera and Treichelia, they are of limited use as a diagnostic character for genera, but are useful for distinguishing species.

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Johnson, Gregg A., David A. Mortensen, and Carol A. Gotway. "Spatial and Temporal Analysis of Weed Seedling Populations Using Geostatistics." Weed Science 44, no. 3 (September 1996): 704–10. http://dx.doi.org/10.1017/s0043174500094571.

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An intensive field survey of an eastern Nebraska corn and soybean field was conducted to characterize the spatial structure and temporal stability of broadleaf weed seedling populations over two growing seasons. Anisotropy, the effect of direction on the relationship between observations, is present in the semivariogram for the velvetleaf and common sunflower populations in 1992 and 1993. The directional trends in aggregation are visible in kriged maps as elliptical shapes oriented east to west across the study area. In addition, there are two distinct zones of aggregation from north to south. These two distinct areas of aggregation are reflected as a ‘plateau’ in the north-south semivariogram. The distance over which this plateau extends indicates that the shape or size of the patch is contracting in the north-south direction (perpendicular to the crop row). The slope of the semivariogram in the east-west direction (aligned with the crop row) remains consistent from 1992 to 1993 suggesting that the shape of the patch is not changing. For sunflower populations, the slope of the north-south empirical semivariogram changes at 20 m, similar to the velvetleaf population semivariograms. This change, however, is reflected as a downward trend in the empirical semivariogram. The distance over which this trend occurs increases from 1992 to 1993 suggesting that seedling patch size was smaller in 1993 compared to 1992. Weed seedling establishment resulting from seed dispersal, differential seed and seedling mortality, or emergence may have resulted in the observed patch dynamics.

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Karlsson, L. M., and P. Milberg. "Seed dormancy pattern and germination preferences of the South African annual Papaver aculeatum." South African Journal of Botany 73, no. 3 (July 2007): 422–28. http://dx.doi.org/10.1016/j.sajb.2007.03.007.

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35

Sahu, P. K., A. P. Sahu, P. S. Brahmanand, B. Panigrahi, D. M. Das, B. C. Sahoo, and D. K. Swain. "Effect of deficit irrigation on yield and water productivity of sunflower in East and South-eastern coastal plains of Odisha." Journal of Environmental Biology 42, no. 4 (July 1, 2021): 1062–69. http://dx.doi.org/10.22438/jeb/42/4/mrn-1428.

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Aim: To study the effect of deficit irrigation on yield and water productivity of sunflower in East and South eastern coastal plains of Odisha. Methodology: The present study on water productivity was undertaken using hybrid sunflower (Swathi: NSFH-145) with application of deficit irrigation having Management Allowable Deficit level of 20%, 40%, 60% and one farmers’ practice of 70% MAD level of irrigation. Growth attributes like leaf area Index, plant height, and head diameter were recorded at 20, 45, 65 and 80 days after sowing. Yield attributes like 1000 seed weight (test weight), above ground biomass and grain yield, were recorded after threshing. Results: The growth, yield and water productivity of sunflower were significantly influenced by different irrigation levels. Irrigation scheduling at 20% MAD level showed the highest grain yield, while the lowest yield was obtained from the farmers’ practice. Irrigation at 60% MAD level showed the highest water productivity when compared with farmer’s practice as it produced the highest yield per unit quantity of water application of 0.85 kg m-3 and also produced the highest average benefit to cost ratio of 2.08. Interpretation: Taking the yield, water productivity and benefit-cost ratio into account, irrigation at 60% MAD level was found to be the best. However, irrigation at 50% to 60% MAD level may be suggested for growing sunflower under water scarce conditions in sandy loam soil for increasing water productivity.

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Nam, Kyong-Hee, and Sung Min Han. "Seed Germination of Sunflower as a Case Study for the Risk Assessment and Management of Transgenic Plants Used for Environmental Remediation in South Korea." Sustainability 12, no. 23 (December 3, 2020): 10110. http://dx.doi.org/10.3390/su122310110.

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In South Korea, the safety management of living modified organisms (LMOs) is regulated by seven government agencies depending on their use, and the Ministry of Environment is in charge of LMOs to manage environmental remediation and effects on natural ecosystems. This study aimed to develop appropriate research tools to determine the factors affecting the invasiveness of transgenic plants used for environmental remediation. We examined the persistence of sunflower (Helianthus annuus L.) as a candidate by comparing the seed viability at different controlled temperatures and soil depths (ranging from 0 to 30 cm). The germination characteristics of seeds significantly differed between cultivars and temperatures. The field trials indicated that seeds buried at a depth of 30 cm mostly decayed within three weeks, whereas those buried at 0 cm persisted for eight weeks but decayed after sixteen weeks, implying a significant interaction between burial depth and seed persistence. At all soil depths, no dormant seeds were detected over one week after burial. These results suggest that sunflower seeds could not be successfully established under our experimental conditions. Since seeds on the soil surface demonstrated the highest rates of germination, such seeds may require particularly careful management to prevent unintended effects on ecosystems.

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Thompson, JA, and DP Heenan. "Effect of sowing time on growth, yield, and oil characteristics of irrigated sunflower in southern New South Wales." Australian Journal of Experimental Agriculture 34, no. 2 (1994): 255. http://dx.doi.org/10.1071/ea9940255.

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The effect of sowing time on the growth, yield, and oil characteristics of irrigated sunflower was studied for 3 consecutive seasons at Leeton (34�28�S., 146�25'E.), in southern New South Wales. The hybrid cultivar Hysun 32 was sown at monthly intervals from late October to late January. Duration of growth from sowing to physiological maturity was reduced by I5 days when sowing time was delayed from late October to late December. Dry matter production at flowering was lowest from the late December sowing, and harvest index was always lowest from the late January sowing. Late October and late November sowing produced similar yields (>4 t/ha), but delaying sowing further to late December and late January reduced yields by 18 and 37%, respectively. Effect of sowing time on yield was mainly related to effects on seed number per head. Seed oil content averaged 50%, with the late November sowing producing the highest value in all seasons. To be confident of producing a linoleic acid level >62% as required for the margarine industry, sowing should be delayed until mid November.

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Sedlářová, M., Z. Trojanová, and A. Lebeda. "Distribution and harmfulness of Plasmopara halstedii on sunflower in the Czech Republic." Plant Protection Science 49, No. 1 (February 12, 2013): 1–10. http://dx.doi.org/10.17221/62/2012-pps.

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In 2007–2012 the first detailed study of P. halstedii distribution and severity was performed in the Czech Republic by monitoring altogether 128 localities. Incidence of the pathogen was recorded at seven localities in south-eastern (Central and South Moravia) and central parts (East and Central Bohemia) of the country; at only four localities the occurrence of sunflower downy mildew symptoms and pathogen sporulation were recorded repeatedly. In all cases the primary infection prevailed, and the severity of infections was rather low. The majority of records were for sunflower experimental fields (e.g. fields of Central Institute for Supervising and Testing in Agriculture. Brno-Chrlice, Czech Republic), one record came from a commercial field and one record from a hobby field. Results of surveys indicate that reservoirs of primary inoculum likely exist in the soil contaminated by P. halstedii oospores in these habitats, but additional transfer by infected seed may be possible. Historical and geographical consequences of recorded infections are discussed, as well as virulence variation in the Czech pathogen populations which is currently in the process of investigation.

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Brown, Kate, and Grazyna Paczkowska. "Seed biology of two invasive South African geophytes and implications for natural area management." Ecological Management & Restoration 9, no. 3 (December 2008): 232–34. http://dx.doi.org/10.1111/j.1442-8903.2008.00425.x.

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Brown, N. A. C., H. Jamieson, and P. A. Botha. "Stimulation of seed germination in South African species of Restionaceae by plant-derived smoke." Plant Growth Regulation 15, no. 1 (July 1994): 93–100. http://dx.doi.org/10.1007/bf00024681.

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41

HARA, Setsuko, Ryo FUKASAWA, Teruyuki NAKANO, and Yoichiro TOTANI. "Evaluation of Anti-oxidative Activities of South African Herbal Tea and Grape Seed Extracts." Journal of Oleo Science 54, no. 12 (2005): 627–32. http://dx.doi.org/10.5650/jos.54.627.

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42

N H Bamata and K K Govender. "Start-up Awareness and Access toFinance: The Case of South African SMEs." Restaurant Business 118, no. 10 (October 18, 2019): 391–400. http://dx.doi.org/10.26643/rb.v118i10.9333.

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Start-up entrepreneurs in South Africa do not move from the stage of existence and survival to growth to maturity/ In order for Start-up businesses to have a competitive advantage, they have to grow beyond the survival stage and keep on growing. Despite the availability of external finance, access to finance from banks has been identified as the main challenge to the establishment and growth of SME Start-ups in South Africa. The aim of this study is toinvestigate the determinants of start-up awareness to improve access to finance from banks by Start-up entrepreneurs in Pietermaritzburg, the capital city of KwaZulu-Natal province in South Africa. Data was collected through self-administrated questionnaires from a random sample of 253 respondents being members of the Chamber of Commerce in the capital city of one of the largest provinces in South Africa.The results from inferential statistical analysis revealed that start-up awareness factors such as conducting a feasibility study, finding a good location, knowing the amount of seed capital needed, developing a business strategy, a business plan, and business model as well as the source of seed capital, are significant determinants of access to bank financing by start-up entrepreneurs.Thus, entrepreneurs should understand the determinants of Start-up awareness in order to improve their ability to access bank finance.

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43

Jones, D. "Feeding Ecology of the Cockatiel, Nymphicus-Hollandicus, in a Grain-Growing Area." Wildlife Research 14, no. 1 (1987): 105. http://dx.doi.org/10.1071/wr9870105.

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The feeding ecology of the cockatiel Nymphicus hollandicus was studied in a grain-growing district near Moree, in northern New South Wales, between August 1980 and June 1982, by direct observations and monthly collections of birds in feeding flocks. Cockatiels fed from the ground, on fallen seed or by felling stems, and, when feeding on sorghum and sunflowers, while perched on the seed heads. The mean size of a feeding flock was 27; large flocks of more than 100 birds were formed only during periods of limited food supply. Cockatiels showed a clear preference for sorghum over sunflowers, and when on cereals they appeared to prefer softer, younger seed to harder, mature seed. Overall they fed on 29 seed types, including four grain-crops, 17 grasses and eight non-grass ground plants. Sorghum was by far the most important food item, making up almost 60% of total crop contents; sunflower made up only 6% of crop contents, and grasses 19.3%; 90% of this last was contributed by Phalarisparadoxa and Setar~a sp. Some management implications, based on apparent food preferences, are discussed.

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Gamayunova, V. V., and I. S. Moskva. "Influence of nutrition optimization on the main indicators of quality of false flax seeds for cultivation in the south of Ukraine." Bulletin of Kharkiv National Agrarian University named after V.V. Dokychaiev. The series “Crop production, selection and seed production, fruit and vegetable growing” 2019, no. 2 (December 27, 2019): 99–109. http://dx.doi.org/10.35550/visnykagro2019.21.099.

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This article highlights the importance of low-investigated and insufficiently widespread oilseed crop of false flax, which can become an alternative to sunflower and other oilseeds. The false flax is unpretentious to growing conditions, it responds well to the optimization of nutrition, italso significantly increases the yield of seeds. Researches were carried out during 2014-2016 on southern Chernozem in the Educational-scientific-practical center of Mykolaiv National Agrarian University with the crop of false flax (variety Stepovyi 1). The optimization of plant nutritionwas investigated by using modern growth-regulating drugs on the background of N15P15K15, that is, on the principles of resource conservation. The influence of nutrition on the main indicators of seed quality was determined.It was determined that depending on thenutrition background not only the level of yield changed but also the quality of seeds. Thus, the protein content considerably increased as well as the conditional harvest per unit of area; the fat content, on the contrary, reducedwith improved nutrition, but in the fatty-acid composition of the oilthe content of the most valuable linoleic acid increased without increasing the amount of erucic acid. According to the research the introduction of false flax crop into production can partially replace the area under the sunflower since it is not inferior to thesunflower on the main criteria of the oil quality as well as on the indicators of its economic efficiency. Keywords: false flax, biopreparations, nutrition optimization, seed quality, fatty- acid composition of oil, fat and protein content.

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Seepe, Hlabana A., Kafua E. Lodama, René Sutherland, Winston Nxumalo, and Stephen O. Amoo. "In Vivo Antifungal Activity of South African Medicinal Plant Extracts against Fusarium Pathogens and Their Phytotoxicity Evaluation." Plants 9, no. 12 (November 27, 2020): 1668. http://dx.doi.org/10.3390/plants9121668.

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Smallholder farmers play a major role in crop production towards household food security, particularly in resource-poor communities. Maize is a common crop produced in smallholder farming and it is cultivated from seeds that has been stored and re-used for years. Spoilage of stored grains is a major challenge, which leads to yield loss and poor seed quality. The objectives of this study were to evaluate in vivo antifungal activity of selected plant extracts against Fusarium pathogens on maize seeds, and to evaluate their phytotoxicity on seed germination and seedling growth. Fresh leaves collected from eight medicinal plants were dried and selectively extracted with water, ethyl acetate or acetone. The dried extracts were evaluated for antifungal activity against Fusarium pathogens (F. proliferatum, F. oxysporum, F. subglutinans, F. verticilloides, F. semitectum, F. chlamydosporum, F. solani, F. equisite and F. graminearum) inoculated on maize seeds. Melia azedarach acetone extract showed strong antifungal activity (97% inhibition) against F. proliferatum while combined acetone extracts from Combretum erythrophyllum and Quercus acutissima exhibited 96%, 67% and 56% inhibition against F. verticilloides, F. proliferatum and F. solani, respectively. With the exception of Quercus acutissima ethyl acetate, none of the extracts significantly inhibited seed germination when compared to untreated seeds. This study showed that plant extracts could control Fusarium diseases without any adverse effects on maize seed germination or plant growth.

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Murray, Colin, and Charles van Onselen. "The Seed Is Mine: The Life of Kas Maine, A South African Sharecropper, 1894-1985." International Journal of African Historical Studies 32, no. 2/3 (1999): 500. http://dx.doi.org/10.2307/220398.

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Worger, William H., and Charles van Onselen. "The Seed Is Mine: The Life of Kas Maine, a South African Sharecropper, 1894-1985." American Historical Review 103, no. 4 (October 1998): 1293. http://dx.doi.org/10.2307/2651300.

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48

Mason, John, and Charles van Onselen. "The Seed Is Mine: The Life of Kas Maine, A South African Sharecropper, 1894-1985." Journal of American History 84, no. 2 (September 1997): 689. http://dx.doi.org/10.2307/2952662.

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Fujita, Tomohiro. "Ficus natalensis facilitates the establishment of a montane rain-forest tree in south-east African tropical woodlands." Journal of Tropical Ecology 30, no. 4 (June 23, 2014): 303–10. http://dx.doi.org/10.1017/s0266467414000224.

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Abstract:Nucleation, leading to the formation of tropical forest patches in open areas, has occurred in many parts of the world. This study examined the role of Ficus natalensis as a nucleus and estimated seed dispersers in the nucleation process. Seed rain and post-dispersal fate of Syzygium guineense ssp. afromontanum (a common forest tree species) under eight F. natalensis crowns were compared with those in other woodland microsites. In addition, focal observations of frugivore were conducted at F. natalensis in the woodlands and S. guineense ssp. afromontanum in the forest, when both species were fruiting. Most dispersed seeds (85%) were found under F. natalensis, and the number of dispersed seeds was significantly greater under F. natalensis than at other microsites. Germination (n = 600) and survival percentages (n = 384) were greater under F. natalensis compared with those in treeless open microsites. These results suggest that F. natalensis act as efficient nuclei in nucleation process. Results of focal observations at S. guineense ssp. afromontanum (100 h) showed that Schalow's turaco consumed 63% of fruit and swallowed all pecked fruit. Schalow's turaco also visited fruiting F. natalensis frequently (0.4 h−1) during 80 h of observations, indicating that Schalow's turaco is an important seed disperser during nucleation.

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Oberholster, Paul J., Christian Blaise, and A. M. Botha. "Phytobenthos and phytoplankton community changes upon exposure to a sunflower oil spill in a South African protected freshwater wetland." Ecotoxicology 19, no. 8 (August 11, 2010): 1426–39. http://dx.doi.org/10.1007/s10646-010-0528-6.

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Journal articles on the topic 'South african sunflower seed'

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