Scientific Journal of KubSAU

A significant decrease in yields of field crops due to lack of moisture enhances the role of adaptive breeding. The development of varieties that combine high productivity and quality and resistance to biotic and abiotic stresses is complicated by a negative correlation between high yield and resistance to adverse conditions. Selection of effective methods for assessing the potential of productivity and resistance to stress factors allows creating varieties that provide stable high yields. We had estimated six varieties of common mustard for 10 years in contrasting weather conditions in the zone of insufficient and unstable moisture of the Azov district in the Rostov region. The necessity of taking into account the indicators of the HTC, the index of the environment and its value when conducting an objective analysis of weather conditions is revealed. The greatest stress resistance, ecological plasticity and stability of the Nika variety were established by calculating the difference between the minimum and maximum yield per year, calculating the coefficient of linear regression and the value of homeostasis. The varieties Lera, Donskaya 8, Lux bred in conditions of insufficient moisture demonstrated maximum genetic flexibility and drought resistance. The greatest breeding value was determined in varieties Donskaya 8 and Lera. These varieties are recommended to be included in further breeding work. The study of mustard varieties in contrast conditions (HTC from 0.30 to 1.53) marked their broad environmental plasticity, which makes it possible to recommend them for cultivation in different weather conditions regions

The article are present the planting dates influence on the onset dates of main development phases and seed yields of the winter rapeseed and camelina. The investigations were carried out in conditions of insufficient and unstable moistening on normal black earth in the Priazovsky zone of the Azov district of the Rostov region from 2013 to 2017 years. The rapeseed variety Loris, the rapeseed hybrid ES Neptune and the camelina variety Penzyak were selected for research in two-factor field experiments. It has been established that the guaranteed yield of winter cabbage oilseeds depends on the timing of the emergence phase and the autumn's weather conditions (the sum of the effective temperatures, humidification conditions) that affect the development of the root leaf rosette. The maximum seed yield was registered in the winter rapeseed variety Loris (4.33 t/ha) in the favorable season 2013-2014 years when was sowing in the second decade of September with an autumn vegetation period of 59 days and the sum of effective temperatures about 320° C. The optimal time for sowing of winter camelina variety Penzyak is first or second decade of September. The maximum seed yield (2.04 t / ha) was obtained in 2013-2014. when was sowing in the first ten days of September with an autumn vegetation period of 70 days and a sum of effective temperatures of 417° C. It was revealed that the seeds of this plant are capable of wintering in the soil and the renewal of vegetation in the spring. The loss of harvest is up to 50 % of the overwintered plants yield that have risen in autumn under unfavorable conditions. The optimum period of autumn vegetation that allows forming the potential productivity of winter rapeseed plants can be considered 60-75 days with sufficient moisture supply and the sum of effective temperatures of 250-400° С. At the winter camelina it was 50-70 days with the sum of effective temperatures not less than 200° С