GENETIC ASPECTS OF POLLUTANT ACCUMULATION IN PLANTS

摘要

The object of our research was to study interspecies and intervariety variability of pollutant (nitrates, heavy metals, radionuclides) accumulation in productive parts of vegetable crops, as well as the character of inheritance of nitrate and heavy metal accumulation in tomato fruits in the open ground. We investigated the genetical basis of cadmium, lead and nitrate accumulation using the diallel analysis method. Genotype variation between tomato varieties and hybrids in diallel crosses in cadmium (12.8-15.5-fold) and lead accumulation (7.5-14.1-fold) was established. It gives the possibility to select tomato varieties for growing in the contaminated area, as well as to use them in breeding for development of new varieties and hybrids with minimum accumulation of pollutants in fruits. An independent type of inheritance of cadmium and lead accumulation was revealed. Genotype variation between tomato varieties and hybrids in diallel crosses in nitrate accumulation (3.8-8.3-fold) was revealed. The general type of heavy metal and nitrate accumulation inheritance in tomato fruits - overdominance towards reduction of pollutant value. To make use of heterosis breeding as a method of development of high-yielding hybrids of tomato for open ground with minimal accumulation of pollutant is proposed. Study of uptake of ~(137)Cs and ~(90)Sr in vegetables in Gomel region (Chernobyl zone) revealed the interspecies genetic variation in ~(137)Cs (tomato -3.1; cabbage -3.3; carrot - 3.0; onion - 0.8-fold) and ~(90)Sr accumulation (tomato - 1.8; cabbage -2.6; carrot - 1.5; onion - 2.3-fold). It gives a possibility to select the genotypes with low content of radionuclides.