SummaryThere is a growing need to increase productivity in poultry. Growth hormones and antibiotics have the ability to improve health, weight gain and feed efficiency in meat-producing animals. The growth-promoting antibiotics are administered to poultry to improve the general performance of the chicken. However, the use of the xenobiotic drugs in food-producing animals has been a concern and a sensitive issue of debate for several decades in the EU and many other regional blocks of the world. Consequently, the use of hormones in animal production has been banned in Italy, Denmark and Germany for over 4-5 decades, while Belgium and Greece had never permitted its use for livestock fattening purposes. Bioactive phytochemicals exhibit antimicrobial, antioxidant, antiparasitic, antiprotozoal, antifungal and anti-inflammatory properties and consequently have several beneficial effects on appetite, growth and the immune status of the animal. In South Africa, different species of pumpkin are produced for food due to their high nutrient content. The flesh serves as a traditional food, while the seeds and peels are commonly discarded. Pumpkin seed extract is reported to be useful for immunomodulation, reproductive health, therapeutics over a wide range of disease conditions and stimulates metabolism of accumulated fats. Studies have also shown that pumpkin seeds are a valuable source of protein and fat. Their complexity and extent of bioactivity offers sustainable prospects for natural control of pathogenic/parasitic organisms, stimulate nutrition or enhance resistance to disease infections, and reduce abdominal fat and serum levels of harmful lipids, while increasing serum levels of beneficial lipids.

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Cowpea (Vigna unguiculata L. Walp. L) is an important leguminous crop largely grown by smallholder farmers in sub-Saharan Africa for food security and animal feed. The objective of this study was to review the production constraints and improvement strategies of cowpea genotypes for drought tolerance. Data were analysed through use of literature review from various sources. In sub-Saharan Africa, cowpeas are produced mainly from West Africa, which accounts for 60% of worldwide production. A lot of pests and diseases affect cowpeas, and this often results in total crop loss. Through continuous improvement, many new cultivars are continually being identified and genetically characterised, and it is thus necessary to evaluate these new lines under different environments. There is a need for multidisciplinary collaborations among breeders and other relevant stakeholders such as farmer and extension workers because the improved cultivars must be according to the farmers preferred traits. Due to declining rainfall pattern in sub-Saharan Africa, there is an urgent requirement for cowpea breeding programmes that focus on developing varieties with short maturity, drought, pest, and disease tolerance. The present review discusses the constraints and improvement strategies of cowpea varieties for drought tolerance.

Sulphur and phosphorus are essential plant macronutrients. Sulphur is involved in the formation of chlorophyll, activation of enzymes and is part of coenzyme A. Phosphorus forms part of the structure of nucleic acids and phospholipids. Two separate studies were conducted to determine the effects of sulphur and phosphorus levels in nutrient solutions on yield and quality of hydroponically grown rose geranium as well as setting standards of sulphur and phosphorus amounts to be used in the production process. The effect of four levels of sulphur (0.36, 1.90, 3.44 and 4.98 mmol l −1) was investigated in the first study and in the second study four levels of phosphorus (0.1, 0.8, 1.5 and 2.2 mmol l −1) were also investigated. All treatments were assigned in a completely randomised block design with five replicates. The results of the first study showed a significant effect of sulphur on the number of branches, plant height and foliar fresh mass. Foliar fresh mass and oil yield peaked at the 3.44 mmol l −1 concentration. The second study showed that plant height and the number of branches was not affected significantly by phosphorus, but foliar mineral phosphorus, magnesium and potassium were affected. Oil yield of rose geranium increased linearly with increased phosphorus concentrations. Both the guaia-69-diene content and the citronellol:geraniol ratio were greater at the highest phosphorus level, which indicated that oil quality can be enhanced by using relatively high phosphorus concentrations in nutrient solutions.

The objective of this study were to conduct association mapping for drought tolerance at the seedling stage and yield-related traits. 60 cowpea accessions were used in the study. Single-nucleotide polymorphisms (SNPs) discovered through genotyping by sequencing (GBS) were used for genotyping. Association mapping was conducted using single-marker regression (SMR) in Q Gene, and general linear model (GLM) and mixed linear model (MLM) built in TASSEL. The population of the cowpea accessions were analysed using STRUCTURE 2.3.4 and the peak of delta K in the greenhouse showed seven population types, whereas the peak of delta K in the glasshouse indicated the presence of six population types. One SNP marker, 14083649|F|0-9 was associated with NP with a p value <0.001. Fifty SNP markers were associated with PWT at p <0.001. Four SNP markers, 14074781|F|0-16, 100047392|F|0-36, 14083801|F|0-28 and 100051488|F|0-49 were associated with AVSPD at p <0.001. SNP markers, 14074781|F|0-16, 14083801|F|0-28 and 100051488|F|0-49 were associated with PL at P <0.001. Five SNP markers, 100047392|F|0-36, 14083801|F|0-28, 100072738|F|0-34, 14076881|F|0-49 and 14076881|F|0-49 were associated with PWDTH at p <0.001. The 65 SNP markers identified can be used in cowpea molecular breeding to select for AVSPD, NP, PL, PWDTH, PWT, and RR through marker assisted selection (MAS).