Identification of resistance sources against post flowering stalk rot in maize

Abstract

Post-flowering stalk rot (PFSR) complex caused by Fusarium verticillioides (Sacc.) and Macrophomina phaseolina (Tassi) Goid, is among the important constraints that limits the productivity of maize (Zea mays L.). The absence of high levels of stable resistant sources to the pathogens has necessitated the continued search and identification of new sources of resistance. The principal goal of this work was once to identify new sources of resistance to PFSR and validate their stability across multi-environments by multi-year testing. A set of 80 elite inbred lines screened in the field against PFSR for three consecutive years at four hotspots in India (Hyderabad, Ludhiana, New Delhi and Udaipur) under artificially created disease epiphytotics. The scores on the scale of 1 to 9 based on the disease reaction were recorded by splitting the stems of each plant. Significant (p=<0.05) interactions of genotype, location and genotype x locations interaction were observed for PFSR resistance. Out of 80 elite inbreds, only 12 inbreds (PFSR/51016-1, CM144, HKI 193-1, PFSR-R2, PFSR-R9, JCY2-1-2-1-1B-1-2-3-1-1, CM117-3-4-1-2-5-2, 42048-2-2-1-1-1-2, JCY3-7-1-2-2-1-3-1-1-2-7-1-1-1, JCY2-7-1-2-1-B-1-2-1-1, LM13 and CM117-3-4-1-2-2-3) had mean disease incidence ≤ 3.0 on the 1-9 scale and the reactions were consistent across the environments. Thus, the identified 12 stable disease resistance sources could be used for developing promising maize hybrids with inbuilt resistance to PFSR disease for different maize agroecologies in India.