Abstract:
The winter and spring
varieties of peas (Pisum sativum) require
careful study of the entire range of
technological measures, including seeding
rates, as the basis for optimal sowing density
and the formation of phytocenose crops. This
issue has not been resolved to date, not only
in the context of agrobiological justification
but also in everyday practice in Ukraine.
This research was carried out in a field
experiment in a three-way factorial
experiment: factor “A” was the type of
development - winter and spring; factor “B”
was the variety - spring peas (Svit and
Darunok Stepu) and winter peas (Moroz,
Enduro and Baltrapp); and factor “C” was
the seeding rate. According to the field
studies, differences in the physiological and
biochemical parameters of the P. sativum
test culture characterised the photosynthetic
activity of the plants, considering the type of
development and variety. The winter
varieties of P. sativum were characterised by
a higher chlorophyll content (by 35–40%)
compared to the spring varieties, which had
an economic effect with an increase in the
yield of dry biomass of the experimental
crop and a decrease in seeding rates, with the
formation and increase in grain yield by 14–
18%. The intensity of chlorophyll in the
process was not a determining factor in the
accumulation of organic biomass. The
extensive nature of the integration complex
was noted (the amount of chlorophyll - the
amount of biomass). At the optimal seeding
rate, a certain specificity was observed in
different types of P. sativum: for spring
varieties, the sufficient rate was 0.9 million
seeds/ha, and for winter varieties, it was 0.7
million seeds/ha. For varieties with a low
productivity level (spring - Svit and winter -
Moroz), the optimum sowing rate was around
0.7 million seeds/ha. The increase in the
seeding rate was accompanied by a decrease in the content of various chlorophyll
fractions from 10–12% to 20–26%.
