Genotypic differences in iron uptake and utilization in some crop cultivars

Abstract

In several parts of India and particularly Maharashtra the occurrence of Fe deficiency has been wide‐spread with respect to localities and also different crop plants. We looked into its causes from the physiological point of view. Several cultivars of plants, viz., rice, sorghum pigeon‐pea, chick‐pea, jute and peanut were grown in complete nutrient solution and later subjected to Fe‐stress conditions. The Fe‐stress tolerance mechanism has been identified in a number of cultivars but there were differences in the mode of reducing the pH of the medium by the roots. A nunber of cotton cultivars including sons hybrids ware also examined and it was found that none of them developed chlorosis; all reduced the pH to nearly 3 in a very short period. The mechanism of Fe‐stress tolerance differed among plant species and the pH reducing capacity did not depend on the onset of chlorosis unlike in sorghum. Our earlier studies showed that in sorghum adventitious roots alone had the capacity to reduce the pH. On the basis of this and other evidences a scheme is presented whereby potassium application could at least partially correct Fe‐chlorosis in monocots.

Key words:

• Fe‐deficiency
• cultivars
• peanut
• cotton
• K‐effect