Tolerance, Heritability, and Heterosis for Aluminium Toxicity Tolerance for ALXMSV Maize Single Crosses

Abstract

Maize is an important cereal crop rated third to rice and wheat on the global scale of agricultural production. It is use spans a vast array of industrial as well as domestic uses, with its consumption as food and feed being the primary reason for its cultivation This globally produced and consumed commodity is however faced with an array of biotic and abiotic constraints with regard to its production, such as MSV, MLND, Smut, Lepidopteron pests, soil acidity, P deficiency, poor rains and drought. This study aimed at assessing tolerance, heterosis, and heritability of Al toxicity tolerance in the laboratory for MSV/AL single crosses in terms of Net root length. The research methodology followed the Magnavaca protocol for Al tolerance screening in nutrient solution. The genotypes in the study varied significantly in terms of response under Al toxicity, with 22.58% tolerant, 19.35% moderately tolerant, and 58.6% being susceptible. From the study, 22.6% of the single crosses were found to be tolerant to the stress under controlled condition and 12.9% were found to have positive heterosis for the trait. While all the female parents were tolerant except AO809, only one male (54B) was moderately tolerant, this could have led to the low heritability expressed by the single crosses for the trait. The identified single crosses should be further screened for tolerance and heterosis in the field. However, this study showed low heritability for Al tolerance (estimated at 16.9%) when crossing is done between susceptible and tolerant genotypes