Chemical analysis and mineral composition of twenty accessions of grain and leaf Amaranth (Amaranthus L.) collected from different agro-ecological zones of Central Malawi were conducted according to the standards of Association of Official Analytical Chemistry (AOAC). Analysis of variance (ANOVA) and means were separated using least significance difference (P ≤ 0.05) in Gen Stat version 15. The analyses for grain Amaranth showed that moisture content ranges from 10.69 to 12.22% while ash content varied from 4.4 to 8.7%. Elemental analyses in mg/100 grams on dry weight basis indicated that the grain had calcium (78.3 to 1004.6), iron (3.61 to 22.51), magnesium (44.31 to 97.38), potassium (267.8 to 473.6) and zinc (0.53 to 1.20). The mean differences for leaf chemical analyses were highly significant (p < 0.001) with crude protein ranging from 13.37 to 23.27%; ash (14.08 to 19.95%) and Vitamin C (30.3 to 117.79 mg/100 g) while the mean mineral leaf analyses in mg/100 grams ranged from 14.84 to 31.17 for iron, 1.03 to 3.46 for zinc, 1512 to 2381 for calcium, 1320 to 1677 for potassium and 383.4 to 513.9 for magnesium. Generally the accessions from mid altitude area of Lilongwe showed highest values for both grain and leaf mineral analyses while accessions from the high altitude showed lower values. The results of this study provide evidence that local Amaranthus genotypes have appreciable amount of nutrients, minerals and vitamins important to meet dietary requirements of rural and urban communities in Malawi.

Common beans are an important nutritious food crop to many people in developing countries. Inadequate soil-P is one of the major constraints to high bean seed yield productivity. Information about genetic effects that control inheritance of root traits in common bean grown under low soil-P conditions is scarce, and that is a challenge for genetic enhancement. This study was therefore implemented to determine inheritance and gene action of root traits in common bean for tolerance to low soil-P. The six generations were evaluated in a completely randomised design with two replicates under low soil-P in a pot experiment. Generation mean analysis revealed that both allelic and non-allelic genetic interactions controlled inheritance of root traits studied. Cumulative main gene effect was higher than epistasis effects. Additive genetic effects were more predominant than dominance effects. Additive and additive × dominance epistatic gene effects were more important in controlling inheritance of root traits under low soil-P. Broad-sense heritability for hypocotyl root number was the highest (93.98 %) while the narrow-sense heritability was moderate (51.13 %). To develop improved genotypes tolerant to low soil-P, recombination crossing should be followed by screening and selection in later generations for high seed yield, root and other preferred traits.

Genes are the sources of information used for creating amino acids which are then assembled to form protein structures (molecules). Together, the various protein structures function in different catalytic and structural activities that are responsible for establishing the phenotypes we see. Although both gene and proteins are equally involved in the biological functions that determine phenotypes, considerable amount of time has been portioned, by geneticists and breeders alike, for dissection of gene architecture and its characteristics comparative to proteins. Proteins are the most versatile macromolecules in living systems and serve crucial functions in essentially all biological processes. They function as catalysts, they transport and store other molecules such as oxygen, they provide mechanical support and immune protection, they generate movement, they transmit nerve impulses, and they control growth and differentiation. Indeed, much of this text will focus on understanding what proteins do and how they perform these functions. Understanding protein structure and its functions is instrumental for advancing molecular sciences. This review attempts to shed some light on structure of proteins, relationship between amino acid sequence and DNA base sequence, hierarchical nature of protein structure as well as the relationship between protein structure and its functions. The information synthesized could provide an insight into the complex nature of proteins and its importance in the perception of biological sciences.

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Background: Drought is a major constraint affecting the seed yield of common bean in smallholder farmers’ fields in Malawi. Therefore, there is a need to develop genotypes that can perform well under drought conditions. The study was conducted to assess the variability of common bean genotypes under stressed and optimum soil moisture conditions. Methods: Forty-three common bean genotypes were evaluated under low and optimum soil moisture in a split-plot pot experiment in 2017. Data were collected at flowering stage on five root traits and seed weight. Result: Highly significant (P less than 0.01) differences were observed among the genotypes and the genotype × water treatment interactions for the root traits and seed weight. Water stress increased hypocotyl root number, basal root number and basal root growth angle by 127.1, 11.3 and 46.1% respectively, while hypocotyl root length, basal root whorl number and seed weight were reduced by 7.1, 1.9 and 9.4% respectively. Broad sense heritability and genetic advance (%) was highest for hypocotyl root length. Genotypes CER-78, SAB-560 and SER-125 were considered tolerant to soil moisture stress and should therefore be tested in various drought conditions for release and used for genetic enhancement focusing on root traits and seed yield.