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Effect of planting date on the phenology, seed yield, and fatty acid composition of three sunflower (Helianthus annuus L.) cultivars
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: R.N. de Vos --- , J. Dreyer --- , J.D. Lea --- Department of Crop Science,Four planting dates (early October to mid-January) were used to obtain a range of environmental conditions for growing three sunflower cultivars. The effect of planting date on phenological development was small compared to that of genotype though the hybrid S0404... -
Invloed van bemesting op die oliekonsentrasie oliekwaliteit van sonneblomsaad
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.L. Loubser --- Olie- en Proteïensadesentrum, Departement Landbou en Watervoorsiening, C.L. Grimbeek --- Olie- en Proteïensadesentrum, Departement Landbou en Watervoorsiening,Influence of fertilization on the oil concentration and oil quality of sunflower seed. Fertilizer trials (N,P,K and lime) were conducted over two seasons at three localities. Results indicate that 150 kg N ha−1 fertilizer decreased the oil concentration of the... -
'n Nuwe benadering tot die bepaling van hitte-eenhede vir sonneblom
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.L. Loubser --- ,Die konvensionele metode vir die bepaling van hitte-eenhede is vergelyk met 'n nuwe benadering. Data uit sewe kultivarproewe insluitende daaglikse maksimum en minimum temperature is gebruik om die hitte-eenhedevereistes van drie kultivars te bepaal. Twee vergelykings is gebruik, een verteenwoordig... -
Die effek van plantpopulasie op die saadopbrengs van sonneblomkultivars
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.L. Loubser --- , C.L. Grimbeek --- , L. A.S. Robertson --- , Beulah Bronkhorst --- , C. Serfontein --- , J.C. van der Sandt --- ,'n Aantal sonneblombasters is vergelyk by drie plantpopulasies oor twee seisoene te Ermelo, Sandvet en Warmbad. Die doel was om die kompensasievermoë van kultivars te bepaal vir 'n swak stand. Onder laepotensiaal-toestande was die kultivar X plantpopulasie-interaksie nie beduidend nie,... -
Invloed van bemesting op sonneblomme. I. Saadopbrengs
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.L. Loubser --- , Republiek van Suid-Afrika C.L. Grimbeek --- , Republiek van Suid-Afrika Beulah Bronkhorst --- , Republiek van Suid-AfrikaBemestingsproewe is by drie lokaliteite oor vier seisoene uitgevoer deur 'n ongerepliseerde 43-gestrengelde faktoriaaluitleg te gebruik. Peile het gewissel van 0 tot 150 kg N ha−1, 0 tot 45 kg P ha−1, 0 tot 60 kg K ha−1 by twee... -
Variasie in lipied- en proteïeninhoud van sonneblomsaad en oliekoekmele in Suid-Afrika
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: G.A. Smith --- Departement Veekunde, Republiek van Suid-Afrika J.P. Hayes --- Departement Pluimveekunde, Republiek van Suid-Afrika Naomi Smith --- Navorsingsinstituut vir Vee- en Suiwelkunde, Republiek van Suid-AfrikaDie variasie in die chemiese samestelling van sonneblom- saad, wat uit verskillende areas aan oliepersers gelewer is, en die invloed daarvan op die samestelling van die geproduseerde oliekoekmele is in die studie ondersoek. Die ontleding van die sade het 'n... -
The importance of certain insects as pollinators of sunflower (Helianthus annuus L.)
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.P. du Toit --- , Republic of South AfricaThis study reports the effects of Apis mellifera L. (honeybees), Astylus atromaculatus Blanchard (spotted maize beetles), Heliothis armigera Hübner (American bollworm larvae) and Musca domestica L. (house flies) on seed set in commercial sunflower. The pollination efficiency of these insects... -
Diversity, abundance and behaviour of diurnal insects on flowering capitula of commercial sunflower in the Transvaal
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.P. du Toit --- Apicultural Unit, Republic of South Africa E. Holm --- Department of Entomology, Republic of South AfricaSunflower, Helianthus annuus L., is an insect-pollinated crop and the different insect taxa visiting the flowering head play a role of greater or lesser importance in cross-pollination. Species diversity, abundance and behaviour of insects visiting commercial sunflower during flowering are... -
Evidence that alachlor selectivity in sunflower is based on depth-protection
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Allemann --- Department of Plant Production and Soil Science, Republic of South Africa C.F. Reinhardt --- Department of Plant Production and Soil Science, Republic of South AfricaThe relative importance of the underground shoot parts (hypocotyl) and roots of sunflower (Helianthus annuus L.) seedlings on the absorption of alachlor [a-chloro-2′,6′-diethyl- N-(methoxymethyl) acetanilide] was studied in a glasshouse experiment. A layer of activated charcoal divided the soil in... -
High availability of alachlor affects the roots and general growth of sunflower seedlings
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Allemann --- Department of Plant Production and Soil Science, Republic of South Africa C.F. Reinhardt --- Department of Plant Production and Soil Science, Republic of South AfricaThe tolerance to alachlor [α-chloro-2′,6′?diethyl-N-(metoxy- methyl) acetanilide] of three sunflower (Helianthus annuus L.) cultivars was evaluated in an aqueous medium in a glass- house. Alachlor (0.79 - 6.32 mg L−1) caused significant reductions in the root and shoot growth of... -
The effect of a diurnal period of supra-optimal temperature on the seed vigour of sunflower
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South AfricaThe daily maximum temperature in the upper 20 mm of sandy soils is often higher than 45°C on cloudless days during November, December and January in the summer rainfall region of South Africa. At these supra-optimal temperatures, sunflower seedling vigour... -
The response of germinating sunflower seed to heat tolerance induction
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South AfricaVigour of pre-emergent sunflower (Helianthus annuus L.) seedlings is reduced when daily peak soil temperatures exceed 44°C resulting in poor emergence. Seedlings of sorghum (Sorghum bicolor L. Moench) are known to acquire thermotolerance to temperatures of 45–50°C as a consequence... -
Die invloed van die voginhoud op die dopbaarheid van sonneblomsaad
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republiek van Suid-Afrika H.L. Loubser --- , Republiek van Suid-Afrika P.S. Hammes --- Departement Plantproduksie en Grondkunde, Republiek van Suid AfrikaDie voginhoud van sonneblomsaad (Helianthus annuns L.) wat vir persing gebruik word, wissel tussen 5.5% (ongeveer die laagste inhoud waartoe saad natuurlik droog) en 10% (die hoogste toelaatbare inhoud vir berging). Die doel van die ondersoek was om vas te... -
Die sif van sonneblomsaad vir die verbetering van olie- en proteienherwinning
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republiek van Suid-Afrika H.L. Loubser --- , Republiek van Suid-Afrika P.S. Hammes --- Departement Plantproduksie en Grondkunde, Republiek van Suid-AfrikaVoor die olie van sonneblomsaad (Helianthus annuus L.) uitgepers word, word dit ontdop om onder andere die kwaliteit van die oliekoek so hoog moontlik te kry. Dopbaarheid, of die gemak van ontdopping, het 'n positiewe verwantskap met saadgrootte. Aangesien saadmonsters... -
The effect of plant population on the quality of sunflower seed for processing
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South Africa H.L. Loubser --- , Republic of South Africa P.S. Hammes --- Department of Plant Production and Soil Science, Republic of South AfricaAmong other disadvantages, low hullability of sunflower seed results in oil cake with a high fibre and low protein content. Hullability is known to increase with increased seed size. Seed size generally decreases with an increase in plant density. The... -
The effect of environment and cultivar on sunflower seed. I. Yield, hullability and physical seed characteristics
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South Africa H.L. Loubser --- , Republic of South Africa P.S. Hammes --- Department of Plant Production and Soil Science, Republic of South AfricaThe quality of South African sunflower oil cake varies and often has an unacceptably low protein and high crude fibre content. Poor hullability of the seed is generally regarded as the primary cause thereof. This study examines the contribution of... -
The effect of environment and cultivar on sunflower seed. II. Composition and processing quality
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South Africa H.L. Loubser --- , Republic of South Africa P.S. Hammes --- Department of Plant Production and Soil Science, Republic of South AfricaThe processing quality of sunflower seed is determined by its oil yield, oil cake yield and oil cake composition. Quality of the oil cake is determined by its protein and crude fibre content. Seed composition is affected by both cultivar... -
The yield and processing quality of sunflower seed as affected by the amount and timing of nitrogen fertiliser
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South Africa H.L. Loubser --- , Republic of South Africa P.S. Hammes --- Department of Plant Production and Soil Science, Republic of South AfricaThe response of sunflower (Helianthus annuus L.) seed yield and seed processing quality to the amount and timing of nitrogen were studied in a field trial. Nitrogen application rates were 20, 70 and 120 kg ha−1 with limestone ammonium nitrate... -
The effect of water stress during grain filling on the yield and processing quality of sunflower seed
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South Africa H.L. Loubser --- , Republic of South Africa P.S. Hammes --- Department of Plant Production and Soil Science, Republic of South AfricaThe oil and protein contents of sunflower seed are affected by water stress. Hullability is a seed quality trait which affects the efficiency of oil extrusion and the quality of the oil cake produced from the seed. Apart from cultivars,... -
Development and validation of relationships between sunflower seed quality and easily measurable seed characteristics for grading purposes
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- , Republic of South Africa H.L. Loubser --- , Republic of South Africa P.S. Hammes --- Department of Plant Production and Soil Science, Republic of South AfricaSunflower seed delivered by farmers is usually traded without taking seed quality into account, owing to the lack of a quick and inexpensive method for quality assessment at delivery points. Seed quality parameters (oil content, protein content, hullability and amount... -
Evaluation of maize cultivars and rotation crops for resistance to damage by fungus-growing termites
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H.F. Riekert --- , South Africa J. van den Berg --- , South AfricaThe fungus-growing termites, Microtermes spp. and Allodontermes spp. are important maize pests in sub-Saha- ran Africa. The use of sunflower and sorghum as alternate or rotation crops with maize to reduce termite infestations was evaluated in field trials in South... -
Weed survey in cotton (Gossypium hirsutum L.) and sunflower (Helianthus annuus L.) fields in the Pandamatenga plains of northeastern Botswana
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.E. Abdullahi --- Department of Agricultural Research, BotswanaSunflower and cotton fields in the Pandamatenga plains of northeastern Botswana were surveyed in 1998 and 1999 for weed infestations. Twenty-seven and 24 species were identified from the fields in 1998 and 1999, respectively. Nineteen and 17 species were found... -
Chemical control of Nysius natalensis Evans (Hemiptera: Orsillidae), a pest of sunflower in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: H. du Plessis --- , South Africa M.J. Byrne --- Ecophysiological Studies Research Group, South Africa J. van den Berg --- School of Environmental Sciences and Development, South AfricaNo insecticide is currently registered for Nysius natalensis Evans (Hemiptera: Orsillidae), control on sunflower [Helianthus annuus L. (Asteraceae)]. Field as well as laboratory trials were conducted to evaluate efficacy of insecticides for N. natalensis control. During budding prior to anthesis,... -
Screening of South African sunflower (Helianthus annuus L.) cultivars for alachlor sensitivity
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: J. Allemann --- Department of Soil, Crop and Climate Sciences, South Africa G.M. Ceronio --- Department of Soil, Crop and Climate Sciences, South AfricaOccasionally a herbicide that is considered safe to use at prescribed rates causes damage to crop plants at those same rates. Alachlor (Lasso EC®) is registered for use on sunflower at a rate of 1.5 to 1.92 kg ai ha−1... -
Grain yield and rainfall use efficiency responses of maize and alternative rotating crops under marginal production conditions in the western Highveld of South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: A.A. Nel --- ,Crop rotation is known to enhance crop yields. It is therefore recommended, regardless of rainfall and soil type, as a counter measure for the risks associated with monoculture maize (Zea mays). Experience in the western Highveld where rainfall is low... -
The effect of canola (Brassica napus) as a biofumigant on soil microbial communities and plant vitality: a pot study
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Clarissa Potgieter --- North-West University, South Africa Misha De Beer --- North-West University, South Africa Sarina Claassens --- North-West University, South AfricaCanola (Brassica napus) may be incorporated into soil as a biofumigant for control of pathogens such as Sclerotinia sclerotiorum. Yet, the effect of biofumigants on natural microbial communities required to maintain soil functions is still unclear. A pot experiment with... -
The effect of bacterial-based biofertilisers and cytokinin on the emergence of sunflower at non-limiting and supra-optimal temperatures
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Andries A Nel --- Agricultural Research Council–Grain Crops Institute, South AfricaSubsurface sunflower (Helianthus annuus L.) seedling growth often deteriorates on sandy-textured soils due to supra-optimal temperature levels on the Highveld area of South Africa leading to poor emergence and suboptimum plant population densities. It has been shown that seedling growth... -
Effect of heat stress on seed yield components and oil composition in high- and mid-oleic sunflower hybrids
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Rouxléne van der Merwe --- Department of Plant Sciences, South Africa Maryke T Labuschagne --- Department of Plant Sciences, South Africa Liezel Herselman --- Department of Plant Sciences, South Africa Arno Hugo --- Department of Microbial, Biochemical and Food Biotechnology, South AfricaHigh temperature stress is a major environmental factor influencing processes such as growth, yield and quality of crops. The objective of this study was to assess the effect of heat stress, applied during grain-filling, on seed yield- and oil quality... -
South African seed oils are safe for human consumption
Item type: Journal Article • Journal: South African Journal of Clinical Nutrition • Authors: M Opperman --- Functional Foods Research Unit, Department of Biotechnology and Consumer Science, AJS Benadé --- Functional Foods Research Unit, Department of Biotechnology and Consumer Science, CF Abrecht --- Cancer Association of South Africa, LL Matsheka --- Functional Foods Research Unit, Department of Biotechnology and Consumer Science,Objectives: A diet that is high in fat and low in carbohydrates is advocated in the recently published The Real Meal Revolution. A suggestion was made in this publication that seed oils are toxic. The authors stated that available seed... -
Effect of conservation agriculture associated crop rotation systems on root and crown rot severity and respective soil-borne pathogens of maize (Zea mays L.) in the Highveld area of South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Maryke Craven --- Agricultural Research Council – Grain Crops Institute, South Africa André A Nel --- Agricultural Research Council – Grain Crops Institute, South AfricaAlthough crop rotation reduces the incidence of soil-borne diseases, reduced tillage practices create the risk of increased disease incidence. Monoculture maize (MM) under both conventional tillage (CT) and conservation agriculture (CA) crop systems were evaluated against two-and three-year rotation CA... -
Emergence response of sunflower (Helianthus annuus) cultivars to supra-optimal soil temperatures
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Lize Henning --- Department of Soil, Crop and Climate Sciences, South Africa Gert Ceronio --- Department of Soil, Crop and Climate Sciences, South Africa André A Nel --- Agricultural Research Council–Grain Crops Institute, South AfricaSeedling emergence is a sensitive stage during sunflower (Helianthus annuus L.) establishment. Abiotic stresses, such as high soil temperatures (above 40 °C), can cause delayed emergence resulting in uneven stand and ultimately poor yields. Therefore, the emergence and early growth... -
Greenhouse evaluation of Trichoderma harzianum for the control of Sclerotinia wilt (Sclerotinia sclerotiorum) of sunflower
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: James R Mathews --- Discipline of Plant Pathology, School of Agriculture, Earth and Environmental Sciences, College of Agriculture and Environmental Sciences, South Africa Benice J Sivparsad --- Discipline of Plant Pathology, School of Agriculture, Earth and Environmental Sciences, College of Agriculture and Environmental Sciences, South Africa Mark D Laing --- Discipline of Plant Pathology, School of Agriculture, Earth and Environmental Sciences, College of Agriculture and Environmental Sciences, South AfricaSclerotinia sclerotiorum, the causal organism of Sclerotinia wilt, is an economically important disease affecting sunflower in South Africa. The goal of this investigation was to evaluate the potential of a strain of Trichoderma harzianum, T77, for control of S. sclerotiorum... -
Design, fabrication and performance evaluation of centrifugal sunflower dehuller for small-scale enterprises in developing countries
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Yuda Lyangalo Benjamin --- Department of Engineering Sciences and Technology, Tanzania Ezra Lazaro --- Department of Engineering Sciences and Technology, TanzaniaSunflower is grown by small-scale farmers in many developing countries like Tanzania. Lack of effective machines for dehulling sunflower seeds has resulted in high oil losses during extraction, especially for small- and medium-scale enterprise. This paper reports on the design,... -
Agricultural supply response for sunflower in South Africa (1947–2016): The partial Nerlovian framework approach
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Kenneth Nhundu --- , South Africa Colleta Gandidzanwa --- , South Africa Petronella Chaminuka --- , South Africa Manana Mamabolo --- , South Africa Sandile Mahlangu --- , South Africa Moraka N. Makhura --- , South AfricaThe study estimates sunflower supply response in South Africa using time series data from 1947 to 2016, modelled through the Nerlovian Partial Adjustment approach. Short- and long-run price elasticities of 0.238 and 0.313 respectively, suggest that farmers do not easily... -
Comparative benchmarking of fertiliser uses for oilseed crop production in South Africa
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: HT Ottermann --- , South Africa SJ Haarhoff --- Stellenbosch University, South Africa KJ Truter --- , South Africa F Meyer --- , South Africa D van der Westhuizen --- , South Africa PA Swanepoel --- Stellenbosch University, South AfricaThis study comparatively benchmarks fertiliser use over two periods (2013–2015; 2021–2023) in South Africa's oilseed crop production [soybean (Glycine max), canola (Brassica napus) and sunflower (Helianthus annuus)] against global trends, with a focus on major oilseed exporters. It explores fertiliser...