Nitrogen fixation and the role of allelopathic factor
Fedorovic, Naumov German
Kharkov State Agrarian University, 312131, Kharkov
|The efficiency of symbiotic and associative
nitrogen fixation to a large extent depends on the chemical interaction of macro- and
micro-components determined by their genotypic features. Enhancement of this interaction
leads to the formation of high-productive agrophytocenosis with a high availability of
One of the means of solving this problem is biological stimulation of seeds and nitrogen-fixing bacteria with biologically active substance, including those obtained from germinating seed-donors, e.g. winter wheat. Aqueous suspension of exudates of germinating seeds and preparations of nodule and associative bacteria has a high stimulative effect on seeds emergence and germination, on plant growth and development and its photosynthetic activity, enhancement of secretive actions of seeds and roots, the formation of biochemical medium in rhizosphere, providing an accelerated formation and functioning of active rhizocenosis or symbiosis.
In order to achieve an optimal effect the variety - acceptors of legumes and non-legumes crops should by selected be the nitrogen fixation supportive feature (nis). The test of the worked-out methods of biostimulation of macro- and microsymbiontes on leguminous crops (pea, soyabean, common bean, chick pea) and on cereals (winter wheat, spring barley) showed the possibility of increasing the efficiency of symbiotic nitrogen fixation with responsive varieties of pea by 3 - 5 times, soyabean - by 2 times and associative nitrogen fixation with different varieties of wheat - bby 1.6-3.7 times. The use of varieties with high reaction response on allelopathic biostimulation of macro- and microcomponents gives the possibility of increasing the yield of grains and leguminous crops without the application of nitrogen fertilizers or with substantial decrease of its quality.