Stalk rots are the most serious and widespread group of diseases in maize. Their nature is often complex as a number of fungi, nematodes and sometimes bacteria are involved in causation of the disease (s). Broadly, they have been divided into pre-flowering (Erwinia and Pythium) and post-flowering stalk rots (PFSR; Fusarium, Macrophomina, Cephalosporium, etc.). Information on distribution, symptoms, inoculation techniques, germplasm evaluation, sources and genetics of resistance and innovative breeding approaches for resistance breeding have been enumerated to understand the complexity of the problem. A systematic breeding program on PFSR resistance began in India since 1993 in collaboration with Asian Region Maize Program, CIMMYT, Thailand. Emphasis has been given on the development of resistant gene pools and inbred lines. Under this program, screening of germplasm was carried out at three hot spot locations in India -Delhi (F. moniliforme), Ludhiana (M. phaseolina) and Hyderabad (C. acremoniumlC. maydis). Since 1994, at these locations every year, the promising genotypes were inoculated and selfed to select resistant plants after the harvest till 1997 kharifwith an aim to derive resistant inbreds and gene pools. During 1997-98 rabi, top crosses have been made using two sets of testers, which will be evaluated for yield and disease reaction subsequently. Also two recombination nurseries, one of white and another of yellow grain were planted during 1997 kharifto develop C1cycle, separately. Afterward, improved version of C2 and C3 cycles will be made, and compared along with Co to find out gains in resistance and yield, if any. Genotypes identified to possess resistance in this process have been listed.

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0208|AGRIS 0201|AL-Maize Program|R01PROCE

CIMMYT Staff Publications Collection