The estimation of the peas varieties (Pisum Arvense L.) on protein percentage in grain: correlation between economic-valuable traits and weather conditions

Peas as a valuable component of animal feed with a high protein percentage is of great importance in solving the problem of increasing protein percentage in grain fodder produced in the country. The current paper has presented the estimation the peas varieties on protein percentage t in seeds. There has been studied the correlation between protein percentage and seed productivity, between 1000-grain weight and length of growing season. There has been identified the influence of weather conditions and the correlation between them and protein percentage t in peas seeds. The trials were conducted at the experimental plots of the peas nursery belonging to the Nizhny Novgorod Research Institute of Agriculture in 2016–2018. The objects of study were 15 peas varieties of domestic and foreign breeding. In the trial there were identified the peas varieties with high protein percentage (28.0–30.0%), with small seeds; the late-ripening varieties, and the varieties with low protein percentage (22.9–23.9%); the early-ripening varieties of a leafy morphotype with large seeds. There has been established a very weak negative correlation (r = –0.010) between protein percentage and grain productivity. There has been identified a very strong negative correlation (r = –0.818) between 1000-grain weight and protein percentage. The protein percentage in pea seeds has got a positive correlation with the length of growing season (r = +0.860). The leafy varieties showed a positive correlation between protein accumulation due to amount of precipitation (r = +0.714…+0.989) and the sum of positive temperatures above 10 ºС (from low, in some cases to high). The leafless pea varieties, at the same time, have got an inverse correlation at the increased humidity