Common bean (Phaseolus vulgaris L.) is a vital source of nutrients worldwide. It is one of the most consumed grain legume in Botswana. Fourteen Andean common bean genotypes were evaluated in four environments (two seasons and two diverse agro-ecologies) to determine the effect of genotype and environment interaction and yield stability. The genotypes were grown in a randomized complete block design with three replications. Grain yield data was analyzed on additive main effects and multiplicative interaction (AMMI), cultivar superiority index, Wricke's ecovalence and Finlay and Wilkinson regression. There was a lack of variation among the selected genotypes, while environment and genotype × environment interaction (GEI) was significant (P <0.01), which is an opportunity to select stable genotypes across environments. AMMI model for total variation revealed that the environment effect was dominant at 36.83%, genotype × environment interaction at 19.82%, while genotype alone was 3.38%. The cumulative sum of squares of the first two interaction principal component axes (IPCAs) accounted for 76.13% of interaction. Stability coefficients consistently identified genotypes DAB494, CAL96 and DAB541 as the most stable and well adapted, besides the low yield realized. These genotypes are useful for stability breeding purposes and for introduction to the semi-arid environment of Botswana.

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The growth and development of wheat and quality of wheat flour is dependent on the genotype, fertilizer application, sowing date and plant density. Therefore, plant growth and protein content studies were conducted on two wheat genotypes during the winter planting seasons of 2015 and 2016. The experiment was laid out in a Randomised Complete Block Design in a split-split-plot arrangement, with the main plots being two wheat genotypes; sub plots being two plant density treatments, sub-sub plots being five nitrogen doses and sub-sub-sub plots of two planting dates, replicated three times. The application of 125 kg/ha nitrogen increased the number of days to anthesis, grain protein content and plant height. Early planting reduced days to emergence but delayed days to anthesis and physiological maturity, whereas the protein content and plant height were increased by early planting. The leaf dry mass, crop growth rate and net assimilation rate were similar at each crop stage for the planting densities, and they were increased at 125 kg/ha application of nitrogen. The genotypes showed the presence of glutens of both high molecular and low molecular weight which are likely to contain genes that supports good baking quality of flour. The interaction of plant density, planting time and nitrogen at 125 kg/ha contributed more protein bands with low and high molecular weight glutenin’s in wheat genotypes.

Two field trials were carried out at the Botswana University of Agriculture and Natural Resources Content Farm (59o24&prime;S, 95o25&prime;E and 993 m above sea level) in Southern Region of Botswana, to evaluate the effects of genotypes on proximate and mineral composition of safflower leaves. Five safflower genotypes (Kiama composite (local), Sina-PI-537598, Gila-PI-537692, PI-537636 and PI-527710) were evaluated in a randomized complete block design (RCBD) with three replications. During the rosette stage safflower leaves (both petiole and blade) were harvested, dried, and ground for analysis. The results showed that safflower genotypes significantly varied in the leaf proximate content of crude protein (24-28%), crude fibre (8-14%), moisture content (86-87%) and dry matter content (13-14%) in both winter and summer growing seasons. The genotype &lsquo;Sina&rsquo; had the highest crude fibre content compared to other genotypes. The average leaf mineral content significantly (p &lt; 0.05) varied from 2-3 mg g-1 phosphorus, 3-4 mg g-1 calcium, 5-6 mg g-1 sodium, 15-17 mg g-1 magnesium and 15-18 mg g-1 potassium. The Na:K and Ca:P ratios ranged between 0.18 and 3.41. All the safflower genotypes evaluated had sufficient nutritional content to be used as a green leafy vegetable for human consumption and food security.

Common bean is the most consumed legume by humans and hence significant for global food security and nutritive value mainly iron (Fe) and zinc (Zn). The objective of the study was to evaluate the effect of harvesting time and genotypes on proximate and mineral composition of common bean. Two field experiments were carried out in Sebele (24o33&prime;S, 25o54&prime;E, 994 m above sea level) horticultural fields during summer 2018/2019. Treatments included two common bean genotypes DAB 564 (white) or 520 (red) and three harvesting stages as the early, mid and late season harvest. In both seasons, genotype and harvesting time significantly (P &lt; 0.05) influenced proximate, macro and micro mineral composition of common bean seeds. Generally genotypes studied had a sufficient amount of proximate and mineral content with crude protein, iron (Fe) and zinc (Zn) content as the most abundant minerals at a range between 20-22%, 33-101 mg g-1 and 41-45 mg g-1, respectively across harvesting times. Genotype DAB 564 (white coloured) significantly (P &lt; 0.05) produced seeds with the highest concentration of proximate and mineral contents especially zinc (45 mg g-1) and iron (70 mg g-1) content irrespective of season. Harvesting common bean seed early or mid-stage produced high seed concentration of proximate, micro and macro mineral content across genotype or season.