Agronomic performance of maize hybrids under Aspergillus flavus inoculation in Cameroon

Abstract

Maize (Zea mays L.) is a major staple crop in most of the sub-Sahara Africa (SSA) region, constrained by a multitude of plant diseases, with the ear and kernel rots being the most widespread and difficult to manage on maize. The objective of this study was to access the agronomic performance of F1 maize hybrids exposed to Aspergillus flavus, under different agro-ecological conditions, in Cameroon. A total of 120 genotypes of maize, including four commercial hybrids, were evaluated under A. flavus infection at two sites; namely Bangangte in the Western Highlands and Mbalmayo, in the Bimodal Humid Forest Zone of Cameroon. The study was conducted during 2020 - 2021 cropping seasons. Results revealed that at Bangangte site, six (89343X88094, 88099X88094, 90204XExp 124, 89246X87036, TZI-5-1171XExp 124 and 90219X1368) out of the top 20 high yielding hybrids, had significantly high (p<0.001 tolerance (0% severity) to Aspergillus ear rot infection. At Mbalmayo site, eight (8923X88094, TZI-5-1171XExp124, 89343X88094, 90219X87036, 89243X87036, 87014X88094, TZSTR1150X87036 and 89248X88094) out of the top 20 high yielding hybrids also showed significant high (P<0.001) tolerance (0% severity) to Aspergillus ear rot infection. The interaction between hybrids and location was significant (P<0.05) for all measured traits, except ear height, grain texture, ear insect damage and husk cover (P>0.05). The pooled broad sense heritability of hybrids in the two locations varied from 5% for grain texture to 92% for days to 50% physiological maturity. Grain yield was negatively correlated with Aspergillus ear rot disease incidence and severity. Hence, promising high yielding maize hybrids with appreciable tolerance to Aspergillus ear rot disease could be selected among the tested genotypes.