Influence of climatic indicators on the dynamics of the growing season duration and forecasting vegetable peas’ harvest date

Abstract

The aim of the study was to determine the variability of climatic factors, to assess their influence on the yield and the duration of interfacial periods of vegetable pea varieties. The experiment was carried out from 2000 to 2019. 4 varieties with shrunken seeds of different ripening groups were studied. For interfacial periods, the sum of effective temperatures above 4.4 °C (ET), the sum of heat units from 4.4 °C (HU), the sum of active temperatures above 10 °C (SAT), the sum of precipitation (SP), the hydrothermal coefficient (HTC), the number of days with temperatures above 30 °C (T>30 ° C), with precipitation from 1 to 20 mm/day (1<P, mm<20) and with precipitation over 20 mm/day (P, mm>20) were calculated. In the south of Russia, the yield of vegetable peas is limited by precipitation frequency (from 1 mm to 20) on the days from sowing to technical ripeness. The studied parameters of environmental conditions characterizing the provision of moisture (HTC, SP, 1<P, mm<20, P, mm>20) and the number of days with T>30°C have a high level of variability. The number of days from sowing to sprouting and SAT of the “sprouting-technical ripeness” period are stable traits recommended for predicting the harvesting date of vegetable peas. A significant reduction in the growing season and its components was established in varieties of medium and late ripening when comparing modern (2000-2019) and earlier data (1964-1990). The results obtained indicate climatic changes, in connection with which it becomes necessary to use earlier varieties in production.