Genotypic variation for Mn efficiency in durum wheat (Triticum turgidium L. var. durum)

Abstract

Crop species differ in their tolerance to Mn deficiency and among cereals, durum wheat has frequently been reported to be less tolerant than barley and bread wheat. Development of Mn efficient durum wheat genotypes could decrease fertiliser requirements and overcome yield losses through better crop establishment. Our earliest attempt to develop criteria for screening durum wheat as a prelude to a breeding program, led to the observation that durum wheat has a higher critical level of manganese in young seedlings than other small grain cereals. It was also noticed that manganese efficiency in the field was highly correlated with shoot Mn content.

Further study of six genotypes selected from our preliminary screening, representing a wide range of variation in Mn efficiency (both field and controlled environment) showed considerable genotypic variation for Mn efficiency exists in current germplasm (a relative yield of 58% in Stojocri 2 as compared to 15% in check cv Yallaroi). The ranking of genotypes on the basis of seedling Mn content was in close agreement with that of relative grain yield, relative dry matter production and chlorosis score (respectively r = 0.80, r = 0.83, and r = 0.85 α = 0.05). Breeding for Mn efficiency in durum wheat is now feasible considering genotypic variation available in current germplasm. The consistent selection criteria (seedling Mn content) has potential application for screening of germplasm and also further genetic study.