INFLUENCE OF THE SOIL MOISTURE REGIME ON THE NITROGEN AND PLASTID PIGMENTS CONTENT IN WHEAT VARIETIES

摘要

Field experiment with 12 wheat varieties was conducted on meadow-cinnamonic soil in experimental station of the ISS "N. Poushkarov' in Tzalapitza, Plovdiv region. The realised variants of the soil moisture regime were: non-irrigated and optimum irrigated in 3 replications. The contents of NH_4~+, NO_3~ in mg/100 g soil, were determined in soil samples. The content of N in % in the wheat straw and wheat-ears, and the content of chlorophyll a and chlorophyll b in the wheat biomass for different wheat varieties of the non irrigated and optimum irrigated variants were evaluated. As it was expected, the results showed significant higher N-concentration in the wheat-ears than in the straw. On the basis of the results can be concluded that under non-irrigated conditions the N-content varied more for the different varieties than that under optimum irrigation. The results for nutrient elements in the accumulated biomass and ears were similar to those reported by other authors. It was found that the content of the two studied pigments chlorophyll a and chlorophyll b was higher for the more of varieties under non-irrigated conditions than under irrigation conditions. Probably the reason for this was the so-called dilute effect, observed from some authors at other crops.