Yield and quality of soybean seeds depending on inoculation and fertilizing in the conditions of the Right Bank Forest Steppe
Authors: Svystunova I. , Furman О. , Furman V. 
Published: October 2022

The defining condition for increasing soybean crops productivity is the development and implementation of technologies for its cultivation, which most fully meet the genetic characteristics of the variety and take into account the interaction of plant organisms with the combined effects of hydrothermal conditions and anthropogenic factors. Among the criteria for assessing the effectiveness of technological methods of growing crops, one of the most important is their impact on the yield and quality of marketable products. The aim of the research is to establish the effect of seed inoculation by a multifunctional microbial preparation based on nitrogen-fixing and phosphorus-mobilizing bacteria and different doses and terms of mineral fertilizers application on yield and quality indicators of soybean seeds of different maturity groups in the Right-Bank Forest-Steppe conditions.

Field research was conducted during 2013-2015 in the research field of SE "RF" Salivonkivske " Institute of Bioenergy Crops and Sugar Beets NAAS, of Ukraine. The soil of the experimental site is typical low-humus medium loam chernozem. The humus content in the layer 0-20 cm - 4.56%, in the layer 20-50 cm - 4.27%, the pH of the salt extract - 6.7-7.2. Content of easily hydrolyzed nitrogen (according to Cornfield) - 155-161 mg/kg of soil, mobile phosphorus (according to Chyrikov) - 44-54 mg/kg of soil, exchangeable potassium - 95-107 mg/kg of soil.

The establishment of the field experiment involved the study of the action and interaction of three factors: A – variety: Vilshanka (early-ripening), Suzirya (medium-ripening); B – pre-sowing seed treatment: without inoculation, Phosphonitragin; C - fertilizers: without fertilizers (control); P60K60; N15P60K60; N30P60K60; N45P60K60; P60K60 + N15; N15P60K60 + N15; N30Р60К60 + N15. Predecessor - winter wheat. Soybean cultivation technology is generally accepted for the Right-Bank Forest-Steppe of Ukraine, except for the factors studied in the experiment. The fertilizing system provided for the application of phosphorus and potassium fertilizers (granular superphosphate and potassium salt) at the rate of P60K60 for basic tillage, as well as nitrogen (ammonium nitrate) - according to the experimental scheme: for pre-sowing cultivation and fertilizing in the budding phase. Inoculation was performed by a complex bacterial preparation for soybeans based on strains of nodule bacteria (Br.japonicum) and phosphorus-mobilizing microorganisms (B. mucilaginosus).

Weather conditions in the years of research differed significantly from each other and relative to long-term averages. In 2013, the growth and development of plants took place at an average daily temperature in the range of 19.1-19.8 ℃, the amount of precipitation - 251.4-334.0 mm and the amount of active temperatures (> 10, ℃) - 2036.3-2258, 7 ℃. In 2014, the values of these indicators were, respectively, 18.6-19.5 ℃, 308.7-337.2 mm and 2020.4-2216.7 ℃; in 2015 - 21.1-21.6 ℃, 135.3-166.5 mm and 2040.5-2324.4 ℃.

The aim of the research to establish the effect of seed inoculation by multifunctional microbial preparation based on nitrogen-fixing and phosphorus-mobilizing bacteria and different doses and terms of mineral fertilizers on yield and quality of soybean seeds different ripeness groups.

Methods - field (to study the interaction of the research object with biotic and abiotic factors), combine harvesting (to determine the seed yield), biochemical - to determine the quality of the crop; statistical (to determine the probability of research results).

It was found that the most favourable conditions for the maximum productivity of crops formation of early-maturing soybean variety Vilshanka and medium-ripening variety Suzirya both in terms of yield and yield of crude protein and oil were created by seeds bacterization by Phosphonitragin and mineral fertilizers + N30P60 . According to these indicators, the reaction of varieties to the action and interaction of technological techniques studied in the experiment was similar. Retail application of nitrogen fertilizers (for pre-sowing cultivation and fertilizing in the budding phase) contributed to the formation of higher plant productivity than a single application of the same rate of nitrogen fertilizers.

Model of growing technology of intensive soybean varieties Vilshanka and Suzirya, which involved seeds inoculation by bacterial preparation based on strains of nodule bacteria (Br. Japonicum) and phosphate-mobilizing microorganisms (B. mucilaginosus) and application of N30P60K60 as base fertilizer and fertilizing provided the highest yields - 2.91 and 3.17 t/ha, respectively, which is more than in the control by 54.0 and 44.7%. In the same variant, the highest yield of crude protein and oil was obtained - in the precocious variety, respectively, 1.18 and 0.62 t/ha, in the medium-ripe variety - 1.32 and 0.63 t/ha.