Response of provitamin-A maize germplasm to storage weevil Sitophilus zeamais (Motschulsky)
By: Frejus A. K. Sodedji, Daniel B. Kwemoi, Godfrey Asea, Samuel Kyamanywa
Key Words: Biofortified maize, Storage pests, Maize weevils
Int. J. Agr. Agron. Res. 9(5), 1-13, November 2016.
Development and dissemination of biofortified maize is essential for communities at risk of malnutrition. This further requires that the improved maize varieties retain all their nutritional attributes up to the end users. Weevils (Sitophilus zeamais) are among the most economically important storage pests of maize in the tropics and present a permanent threat to the availability of maize nutrients for human consumption. This study aimed at evaluating resistance to maize weevils in 24 provitamin-A maize inbred lines and their single cross hybrids. Evaluation was done by artificial infestation and the Dobie Index of Susceptibility was used to group the genotypes. Results showed that Provitamin-A maize genotypes evaluated were in general susceptible to S. zeamais. Two inbred lines CLHP0014, and CLHP0005; and five single crosses; CLHP00434/CLHP0020, CLHP00306/CLHP0005, CLHP00434/CLHP0003, CML486/CLHP0005, CLHP0331/CLHP0020 were moderately resistant to S. zeamais. Grain damage (GD) was strongly positively correlated with number of F1 weevils which emerged (R2= 0.74, P<0.001). The index of susceptibility (IS) was positively and strongly correlated with number of weevils which emerged (R2= 0.86, P<0.001) and grain damage (R2= 0.69, P<0.01). Susceptibility of the maize genotypes was not correlated with differences in kernel colours. Lines with moderate resistance to weevil were identified and could be improved for the use in developing nutritional qualities maize varieties to minimize loss due to storage pests.