EFFECT OF FOLIAR SPRAYING WITH ZINC SULPHATE IN THE QUALITATIVE AND PRODUCTION CHARATERISTICS OF TWO VARIETIES OF CUCURBITA PEPO L PLANTED UNDER PLASTIC HOUSES.

An experiment was carried out to investigate the effect of zinc sulfate on the qualitative and production characteristics of two varieties of Summer Squashplanted underplastichouses. The study was included two factors: the first factor was two varieties of Summer Squash(V1 Carisma) and (V2 Alexandria) and the second factor was represented by five concentrations of zinc sulfate (0, 25, 50, 75, 100 mg). The experiment was of Randomized Complete Block Design RCBD design with three replicates as a factorial experiment (2 x 5). The experiment included 10 treatments and 30 units, each unit includes 8 plants. The obtained results were analyzed by SAS program and the averages were compared by the Duncan Multipliers test at a probability level of 5%. The present results showed that the varieties varied in most productivity and quality traits. Alexandria was significantly higher in the number of male and female flowers, number of fruits, weight of fruit, plant yield, total yield and carbohydrates with mean values of 16.13 flower/Plant^-1, 35.19 flower/Plant^-1, 14.28 fruit/Plant^-1, 172.08 g/Plant^-1, 2.40 kg/plant^-1, 4.03 ton/B^-1 and 17.38% respectively. Spraying with zinc sulfate at concentration of 75 mg/L^-1resulted in a significant increase in the number of male flowers, the fruit weight, plant yield and the total yieldwith means of 18.00 flower/plant^-1, 179.17 g/plant^-1, 2.51 kg/plant^-1 and 4.22 tons/ B^-1 respectively. Additionally, the interaction between Alexandria and sprayingwith a concentration of 75 mg/L^-1of zinc sulfate was significantly higher in the number of male and female flowers, number of fruits, fruit weight, plant yield, total yield and carbohydrates. The highest sex ratio (2.57) was noted in the treatment of the interaction between Carisma and spraying with a concentration of 75 mg/L^-1 of zinc sulfate which was superioron the other interaction treatments. [ABSTRACT FROM AUTHOR]