Polymorphism of microsatellite loci in feral populations and commercial varieties of oilseed rape (Brassica napus L.)

Aim. The aim of the work was to compare the polymorphism of commercial varieties and populations of B. napus growing outside cultivation to assess the genetic diversity of feral rapeseed populations in Belarus. Methods. The study assessed genetic diversity according to the data of 7 microsatellite loci genotyping. Results. The results indicate a greater genetic diversity in feral oilseed rape populations. An analysis of the structure of the genotypes distribution in the STRUCTURE software showed the division into three clusters – commertial varieties, feral populations and samples of B. rapa. Conclusions. The established genetic divergence between feral populations and commercial varieties indicates that feral oilseed rape is able to maintain persistent populations in Belarus. In practice, this should be taken into account when assessing the environmental risk when transgenic rape is released into the environment. And in the cultivation of transgenic rapeseed, special attention should be paid to measures to prevent the occurrence of its free-growing populations. Keywords: oilseed rape, feral populations, microsatellite loci, genetic diversity.

Molecular Investigations of the Soil, Rhizosphere and Transgenic Glufosinate-Resistant Rape and Maize Plants in Combination with Herbicide (Basta®) Application under Field Conditions

A field study was conducted during 1994 to 1998 on the Experimental Farm Roggenstein, near Fürstenfeldbruck, Bavaria, Germany to determine the effect of transgenic glufosinateresistant rape in combination with the herbicide Basta® [glufosinate-ammonium, phosphinothricin, ammonium (2RS)-2-amino-4-(methylphosphinato) butyric acid] application on soil microorganisms and the behaviour of the synthetic transgenic DNA in response to normal agricultural practice. No influence of Basta® on microbial biomass could be detected. The phospholipid fatty acid analysis of soil extracts showed no difference between Basta® application and mechanical weed control, whereas conventional herbicide application revealed a different pattern. Basta® application resulted in a changed population of weeds with a selective effect for Viola arvensis. During senescence, transgenic rape DNA was degraded similar to endogenous control DNA. After ploughing the chopped plant material in the soil, transgenic as well as endogenous control DNA sequences could be detected for up to 4 weeks for rape and up to 7 months for maize, whereas PCR analysis of composted transgenic maize revealed the presence of the transgene over a period of 22 months.