Menu Script Field: Response of Soybean to Water Deficit and Spider Mites During Seed Filling Stage

Morphological, physiological and biochemical responses of soybean were investigated under influence of water deficit and spider mites, imposed during seed filling stage. The pot experiment was conducted under greenhouse conditions and included 3 factors: factor A - mode of irrigation (water deficit and irrigation), factor B - mites (presence or absence of mites) and factor C - imidacloprid (with and without imidacloprid treatment). Imidacloprid was used due to its protective effect in conditions of abiotic and biotic stress. The results showed that the interaction of the stress factors led to a reduction in the leaf area (46.7%), relative water content (17.9%), total content of photosynthetic pigments (39.8%) and to an increase in density of leaf trichomes (23.1%) and content of water-soluble sugars (128.6%). Soybean aboveground biomass was characterized by reduced protein content (by 17.6%) and in vitro digestibility of dry matter (7.2%) and slightly increased synthesis of NDF, ADF and cellulose. Negative consequences of the mites in conditions of both modes of irrigation (+ WD, -WD) showed that they are more pronounced under water deficit than in irrigation regarding plant leaf area, total pigments and biomass protein conten. Treatment with imidacloprid had a positive effect on the stressed plants (+ WD + M + I). It favored the synthesis of water-soluble sugars, leaf pigments and basic parameters such as CP, CF and NDF in the soybean biomass as well as increased the size of leaf area. In future, more investigations are needed to study the effect and the possibility to use different substances to minimize the consequences of biotic and abiotic stress.