Tolerance of Varieties and Hybrid of Pumpkin and Squash to Salt Stress

Irrigated agriculture in arid and semi-arid regions is a practice encouraged to maximize food production, however these regions hesitate a qualitative shortage of water resources, often being necessary the use of saline water, affecting soil and sensitive plants to saline stress. So this study aimed to evaluate emergence, growth, phytomass accumulation and tolerance of the Tetsukabuto hybrid and varieties of pumpkin and squash under salt stress. The experiment was carried out in protected environment (greenhouse), located in the municipality of Pombal, Paraíba, Brazil. Treatments were arranged in completely randomized experimental design with four replicates, in a 5 × 3 factorial scheme, relative to five levels of irrigation water salinity and three genotypes of pumpkin and squash. Pumpkin and squash seedlings were grown on trays of 30 cells with capacity for 0.1 dm3 of substrate, during the first 20 days after sowing, and were monitored for emergence, initial growth, dry matter accumulation and tolerance to salinity. Increment in irrigation water salinity reduces emergence and initial growth of the pumpkin and squash genotypes. The genotypes G2 - ‘Squash cv. Coroa’ and G3 - Tetsukabuto hybrid are more tolerant to salinity than G1 - ‘Pumpkin cv. Jacarezinho’ in the initial growth stage.