BIOLOGICAL FEATURES OF PEA VARIETIES AND LINES AND THEIR RESPONSE TO PLANTING DATES UNDER THE ALTAI REGION’S CONDITIONS
Pea ( Pisum sativum ) is one of the sources of high-quality plant protein production. A wide range of different complementary and stress resistant pea varieties is needed for the Altai Region which is characterized by large territory with zonality and unstable climate. The research goal was to evaluate the available pea varieties, identify the best lines for the Altai Region, and determine their response on agricultural practices, including planting dates. The set of varieties included 10 genotypes of Russian and foreign breeding. The varieties were planted in three dates - the first, second and third ten-days of May. On four-year average, the following leafless forms had the smallest height: Madonna (49.7 cm), Velvet (51.3 cm) and L-37/99K(03) (52.3 cm). Leafy lines and varieties L-L-277, L-20/07-2, L-46/12, as expected, were taller (88.0, 84.3 and 79.0 cm, respectively). The average yields of the standard varieties of the first planting date were 1.59 t ha (Avans) and 2.13 t ha (Batrak). When planted in the third ten-days of May, the yields increased to 2.42 and 2.68 t ha, respectively. Leafy lines L-46/12, L-L-277 and leafless line L-67/2 K-15 had the highest yields. Of the foreign varieties, the Madonna variety had the best indices. The hybrid combinations L-20/07-2 and L-L-277 exceeded the standard variety Avans by herbage yield when planted in the third ten-days of May. High yields of forage crop material among leafy morphotypes are produced with both early and late planting dates. High yield of pea seeds are more likely with the late planting. The leafy lines L-46/12, L-L-277 and the leafless line L-67/2 K-15 were the best lines among the studied ones.