Composition of glucosinolates in biomass of brassica genus and their role in crop system

摘要

Glucosinolates are discussed besides their anti - nutrition effect, also as compounds which create natural defend and with its chemical composition they are ranked among natural pesticides and natural biofumigators. The principle of these effects is passive protection created by the two - component system, glucosinolates - myrosinase. The two - component system of glucosinolate -myrosinase is activated only due to an attack diseases, insects and in the case biofumigators is soil after ploughing in their biomass as green fertilizing or after ploughing in after harvest the left overs of rape. In accordance was observed content and composition of glucosinolates during growth. The most resistance against diseases and insects has white mustard (Sinapis alba) and radish (Raphanus sativus), which differ from Rape, Turnip rape and Brassica juncea, where prevail aliphatic decomposition products.White mustard contains aromatic sinalbin and radish has 4 - ethylsulfinylbutyl glucosinolat- glucoraphanin. Biofumigative effect of Brassica preceding crops lies on the content and composition of Brassica roots glucosinolates considering that during growth the content of glucosinolates decreases and transported in the generative organs and go over from pods into seeds.Brassica crops (Brassica napus var. napus biennis and napus annua, Brassica campestris, Brassica juncea var.biennis, Sinapis alba, Raphanus sativus var. oleiferus) are more suitable preceding crops for the consequently grown winter wheat than the wheat itself. Winter wheat grown after Brassica preceding crops had less leaves on the main stem invaded by leafspots,with minor intensity and substantially less number of Septoria leaf blotch on the flag leaf and it also gave higher yields with higher TSW. These Brassica preceding crops positive results are not only caused their natural biofumigators, but also their large capability to improve physical quality of soil and her microbial activity.