Vermicompost and Vermiwash Minimized the Influence of Salinity Stress on Growth Parameters in Potato Plants

ABSTRACT Potato (Solanum tuberosum L.) is the fourth major crop worldwide after cereals. Some producers use irrigation water with high salinity, which consequently decreases the agronomic yield and potato quality. The aim of this investigation was to determine the effect of vermicompost and vermiwash on plant growth and tuber yield and characteristic traits in Solanum tuberosum L. plants and tubers subjected to salinity stress. A surface response experimental design with three replicates using a central point and 15 treatments was used with vermicompost at 300, 580, and 860 g plant−1; vermiwash at 5, 10, and 15 ml plant−1; and salinity stress with 15, 20, and 25 mM of NaCl levels. Plant physiological measurements included plant height (cm), stem diameter (mm), and plant fresh and plant dry weight (g). Six months after planting, measurements on tuber fresh weight, pH, electric conductivity, and °Brix were carried out. The addition of vermicompost and vermiwash minimized the influence of salinity stress on growth parameters and tuber characteristics in potato plants. Vermicompost (580 g plant−1) plus vermiwash (15 ml plant−1) induced a greater plant height and stem diameter. Plants amended with vermicompost (860 g plant−1), vermiwash (15 ml plant−1), and salinity stress (15 mM) had higher pH values, whereas electrical conductivity value in potato tubers decreased.