STUDY ON TOLERANCE OF DIFFERENT WHEAT CULTIVARS OR LINES TO MANGANESE DEFICIENCY

In Mn-deficient soil of rlce-wheat rotetion ln Sichuan Plain. tolerant of fifteen wheat cultivars or lines to Mn- deficient was Studied in field and pot experiment. The resuits showed that there were considerable differences in tolerance to Mn-deficient among these varieties. Most of wheat varieties were susceptive to Mn-deficient and just a few varieties had high tolerance. Among different wheat varities. variety80-8 was the most tolerant to Mn-deficient and the highest in grain yield, so it is very useful for application in Mn-deficient soils. Different wheat varieties can be screened preliminarily by pot experiment. Under Mn-deficient condition, Mn concentration of. shoot in different cultivars had no significant difference, therefore it could not be used as an index to identify tolerant ability to Mn-deficient. Being consistent with tolerant abilities, visual scores for Mn-deficient symptoms can be used as an index for preliminary screening. Relative grain yield in field experiment is a final index to distinguish different varieties in Mn tolerance. Vigorous root growth and high root-shoot ratio are very important factors for Mn-efficient varieties.