Screening of groundnut germplasm collection and selection of genotypes tolerant of lime-induced iron chlorosis

Abstract

SUMMARYErect type groundnut germplasm belonging to the Valencia and Spanish botanical groups was examined in the field for five consecutive cropping seasons (wet 1988, 1989 and 1990 and dry 1989 and 1990) at Junagadh, India, in order to identify groundnut genotypes with the ability to grow in calcareous soil and tolerate iron deficiency (lime-induced iron chlorosis). On the basis of the visual chlorotic rating scores of their leaves, 17 and 19 genotypes of the Valencia and Spanish groups, respectively, which showed the least or no chlorosis were classified as tolerant (iron-efficient) to iron chlorosis. These genotypes may now be used as donor parents in groundnut breeding programmes for the development of iron chlorosis-tolerant varieties.Almost all the iron-efficient groundnut genotypes had higher pod and seed (kernel) yields and Harvest Index (HI) than the susceptible types. The seed yield of 12 iron-efficient groundnut genotypes was either equal to or higher than a commercial cultivar which showed tolerance to iron chlorosis and, hence, these genotypes could profitably be grown in those areas where chlorosis due to iron deficiency is a major problem.