IMPACT OF HYDROTHERMAL CONDITIONS ON COMMON BUCKWHEAT (FAGOPYRUM ESCULENTUM MOENCH.) PRODUCTIVITY

Investigations were conducted during 2004 - 2014 at the Voke Branch of the Lithuanian Research Centre for Agriculture and Forestry. Research purpose - to identify changes in the productivity of buckwheat depending on the variations in hydrothermal conditions during the growing season. Studies have shown that all investigated buckwheat varieties demonstrated high yield variation (24.3 - 45.5 %) but somewhat smaller variation of biometric parameters (6.2 - 14.7 %). It was found that the trends of increase in variations are associated with reduction of all assessed parameters. This is confirmed by statistically significant correlation between 1000 grains mass and variation coefficient of this parameter (R-2 = 0.4449*). Hydrothermal conditions during the summer season also influenced variation of all parameters. It was found that, due to wetter than optimal hydrothermal conditions in summer, variation of all parameters (except for 1000 grains mass) was lower. Hydrothermal conditions during summer had no effect on the variation of 1000 grains mass. Hydrothermal conditions of separate summer months produced different impact on buckwheat production formation. Rather wet July (if HTC did not exceed 2.5) was favourable and produced a positive effect on buckwheat biometric parameters (R-2 = 0.3475 and 0.4646*) and grain yield (R-2 = 0.4015*). However, at the beginning of vegetation (June) and during grain ripening (August) buckwheat plants require hydrothermal conditions with optimum moisture.