Optimization of soybean cultivation technology on irrigated lands depending on seed inoculation and plant protection

Abstract

Purpose. The work is to study the influence of variety genotype, inoculant and plant protection measures on the formation of plant biometric parameters and grain yield of soybean varieties under irrigation. Methods. The methodological basis of this study is: empirical (field experiments and observations; measurement of the object of study; comparison of the impact of elements of agricultural technologies), theoretical (hypothesis formulation and conclusions based on research results; statistical; mathematical). Results. In field studies with soybean varieties, which included determining the effect of seed inoculation before sowing and comparing the effectiveness of biological and chemical plant protection measures on the formation of the main elements of productivity, in particular seed yield and basic quality indicators under irrigation conditions, multidirectional patterns of plant height formation were determined. It was determined that the maximum plant height (99.1 cm) was obtained by sowing the Deimos variety with seed inoculation with Optimize and the use of a biological plant protection scheme. The minimum value of this indicator, on average by the factor 88.2 cm, was in the variety Phaeton, which is less than other varieties by 6.9–9.7%. Under biological protection, a slight increase in plant height by 2.5% was noted, and under chemical protection – by 3.3%, which indicates the insignificance of the influence of this factor. The height of the lower bean attachment reached the maximum value (21.2 cm) in the variety Deimos under inoculation with Optimize and under biological protection. Inoculation of seeds and plant protection had a minor effect on the value of this indicator. Plant protection had a mathematically evident effect on the formation of seed productivity of the studied soybean varieties. In the control variant (without plant protection, water treatment), this indicator averaged 2.90 t/ha for factor C. The use of biological protection products contributed to an increase in seed yield by an average of 11.1% (up to 3.22 t/ha). Chemical plant protection was the most effective, resulting in a yield increase of 0.46 t/ha, or 15.9%, compared to the control. The difference between chemical and biological plant protection was insignificant and amounted to only 4.3%, with chemical protection being the preferred method. Conclusions. The highest level of soybean seed yield of 3.88 t/ha was obtained in the variety Deimos when the seeds were treated with Optimize and chemical protection was introduced, and its minimum value of 1.77 t/ha was obtained in the plots with the variety Phaeton without the use of inoculants and without the use of plant protection. The preparations Nitrofix and Optimize significantly increased the seed productivity of soybeans when growing all varieties with a yield increase of 6.2–19.8%. It was proved that the use of biological and chemical plant protection systems ensures the preservation of seed yield at the level of 11.1 and 15.9%, respectively. At the same time, the difference between chemical and biological protection is insignificant.