Evaluation of the effect of diazotroph bacterial preparations on potato yield formation in the steppe zone of the Altai Region

Abstract

The influence of microbial preparations containing cultures of nitrogen-fixing associative bacteria on the formation of potato yields under the conditions of the arid steppe of the Altai Region is studied. The research was carried in 2021 and 2022 in a peasant farm enterprise in the Aleiskiy District of the Altai Region. The weather conditions during the growing seasons on these years were unfavorable for crops; there was especially little rainfall in the first half of the growing season. The soil of the experimental plot consisted of leached chernozem of medium thickness, medium humus, with humus content in the arable horizon of 4.9%, and neutral reaction of the soil solution. The influence of the following nitrogen fixing biological products on the growth and development of mid-season potato varieties Colombo and Red Scarlet was tested: Agrofil, Mizorin and Flavobacterin. Positive effects were obtained when inoculating tubers before planting on biometric indices of growth and development of both potato varieties. The height of the shoots, number of stems, leaves, and leaf area increased. The biological products had positive effects on the productivity of tubers increasing their number per plant, the weight of tubers in a plant and their size. As compared to the control, inoculation decreased the fractions of small tubers of 30-50 g and 50-80 g and increased fractions with larger tubers. In the Colombo variety, the fraction >120 g increased maximally on average by 10% as compared to the control; in the Red Scarlet variety, the fraction >120 g increased more significantly - by 17-30%. The product Flavobacterin had greater effect on increasing tuber marketability. Tuber inoculation increased the yields of potato varieties as two-year average by 27.0-63.2%. Both varieties maximized yields when tubers were treated with Flavobacterin by an average of 63%.