The objective of this work was to estimate and compare the growth curve parameters for live weight of indigenous Venda and Naked Neck chickens and carry out some analyses to test the existence of differences in the growth pattern between these breeds. The data were collected from the two breeds of chickens that were reared from day-old to 21 weeks of age. Two hundred chickens (100 of each breed) were used. Three different non-linear models, namely Gompertz, Logistic and Richards, were used to define the growth curves of the chickens. Models were compared using Coefficients of determination (R 2 values), A parameter values, the Durbin-Watson Statistic (DW) test for autocorrelation, computing difficulty based on the number of iterations needed for convergence and size of residual variances. The R 2 were high for all models: 0.996, 0.990 and 0.997 for Gompertz, Logistic and Richards, respectively. Residual variances were 2240, 5924 and 1154 for Gompertz, Logistic and Richards, respectively. The Gompertz model was observed to be suitable for explaining the growth of the chickens. Breed differences were observed in the growth parameters of chickens. The Venda breed was observed to be late maturing and heavier at maturity while the Naked Neck was shown to have a higher growth rate, reaching maturity earlier but attaining a lighter mature weight.

The biotype of the citrus nematode (Tylenchulus semipenetrans) from Zebediela and Champagne Citrus Estates, Republic of South Africa, was determined using 2-year-old differential hosts, namely, grape (Vitis vinifera cv. Richter 110), carrizo citrange (Citrus sinensis × Poncirus trifoliata), rough lemon (C. jambhiri), olive (Olea europaea cv. Misson), and trifoliate orange (P. trifoliata). The study was conducted under greenhouse conditions with 10 replicates. Nematodes from Zebediela and Champagne were extracted from roots through mechanical shaking, sieving, and incubation in Baermann trays and inoculated at 10,000 and 40,000 eggs and juveniles per plant, respectively. Results demonstrated that the citrus nematode from Zebediela had reproductive factors greater than one on grape, rough lemon, trifoliate orange, and carrizo citrange, but lower than one on olive. Reproductive factors were less than one for all differential hosts with the Champagne population, with olive having the lowest value. Differential-host tests using Zebediela and Champagne nematode populations suggested that the T. semipenetrans biotype is poncirus.

Effective crosses among selected parents are crucial for genetic analyses and for the breeding of crop plants. Bambara nut is an indigenous African legume with considerable genetic diversity useful for genetic enhancement of yield and quality traits through breeding. However, the crop has previously received limited research attention. This may be attributed to its extremely small flower size, its flower orientation, the delicate nature of the flower and it's mating system. The aim of this study was to establish a preliminary crossing protocol for Bambara nut for breeding and genetic studies. Controlled emasculation and pollination were performed using eight selected parents, using a diallel mating scheme under glasshouse conditions. Some successful crosses were achieved and F 1 seeds were recovered from the crosses of 211-40-1 x N211-2, N212-8 x 211-40-1 and M09-3 x 211-82-1.

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