The effects of different irrigation and tillage on the physiology of soybean

Abstract

This research was carried out to evaluate the effect of various irrigation regimes and mechanization processes applied with surface drip system on yield plant water stress index (CWSI) and midday leaf water potential (LWP) in the Mediterranean Region. Field studies were carried out in Tarsus Soil and Water Resources Research Unit / Mersin experimental areas during the 2018-2019 growing seasons.In this study, 3 different irrigation regimes were applied (I₁₀₀: Completion to the field capacity of the available water of 60 cm soil depth weekly. I₇₀: 70% of the water applied to I₁₀₀, I₅₀: 50% of the water applied to I₁₀₀), 2 different tillage and sowing method (TP: traditional soil tillage (Plow-discard-harrow-planting), DP: direct planting). In the study, in order to determine the plant water stress, temporally; Leaf water potential (LWP), crop water stress index (CWSI), chlorophyll content (SPAD) and leaf area index (LAI) measurements were made. These physiological measurements were compared with soil water content (SWC), yield and each other.The highest LWP and CWSI were obtained for DPI₅₀ treatments, which had the lowest soil water content. The highest SPAD and leaf area index (LAI) were obtained for the DPI100 subject with the highest soil water content. High correlations were obtained between physiological measurements. Observed that different tillage methods affect soil water content with physiological parameters.As a result, it has been seen that CWSI, LWP and SPAD measurements can be used successfully in determining the water status of soybean.