Genetic variation of some facultative wheat genotypes in terms of accumulation of zinc in the whole grain and endosperm
By: Nikwan Shariatipour, Seyed Siamak Alavi Kia, Mohammad Moghaddam Vahed, Ashkbous Amini
Key Words: DTZ staining, Genetic variation, Wheat, Zinc efficiency.
J. Bio. Env. Sci. 8(1), 167-178, January 2016.
Malnutrition caused by zinc micronutrient deficiency has become one of the growing problems of developing countries. Using varieties which have high uptake efficiency for this trace element is one of the methods to solve this problem. Two separate trials (with and without zinc foliar application) were conducted in the form of randomized complete block design with three replications and then combined analysis of variance was performed on the results, with the purpose of evaluating the genetic variation in facultative wheat genotypes, in terms of their zinc uptake and translocation efficiency, and to ultimately identify genotypes with high content of zinc in the grain and especially in their endosperm. Zinc was added through foliar application in the amount of 0.68 kg/ha at the end of the vegetative stage and start of reproductive stage. Agronomic traits such as grain yield were measured during the growth period. Also two main traits for trial, the amounts of zinc in the whole grain and in the endosperm, were measured by DTZ (1,5-diphenylthiocarbazone or dithizone) staining and spectrophotometry, respectively. The results of analysis of variance indicated high genetic variation for all the studied traits. Zinc content of the endosperm had the highest genetic and phenotypic coefficient of variation and thousand grains weight had the highest heritability. According to the correlation and regression analysis the amounts of zinc in the whole grain and in the endosperm showed no linear relationship with grain yield and their variations were independent from the variations of grain yield.