Effect of sodium chloride salinity on germination and growth of pumpkin seedlings in Maseno (Kenya)

Salinity is one of the most serious abiotic factors that limit agricultural productivity with an adverse effect on germination and growth parameters throughout the world. Sodium ions (Na+) and chlorides (Cl –) ions have been identified to turn agricultural land into unproductive lands unable to support the growth of plants for food and nutrient supplements which results in food insecurity. C. pepo L. plant is a fruit vegetable, a source of food, and nutrients, a medicinal and short seasoned crop that has not only been neglected but also is underutilized. The sodium Chloride salinity tolerance of C. pepo is not well understood; therefore this study was initiated to determine the effect of Sodium Chloride salinity on the germination and growth of C. pepo seedlings. Seed materials were purchased from the East Africa Seed Company (Kitale). They were carried in sealed labeled envelopes in the botany laboratory. The germination test was done using ten seeds under treatment of NaCl (Control 0, 35mM, 70mM, 105mM, and 140mM) using a completely randomized design. A growth experiment was set up in the greenhouse using varied salinity levels of NaCl (Control 0mM, 35mM, 70mM, 105mM, and 140mM). Growth parameters were collected after three days intervals for a period of one month. Chlorophyll a, b, and total chlorophyll were estimated. Analysis of variance (ANOVA) test (p≤0.05) showed that germination was inversely affected by salinity treatment with complete inhibition at higher concentrations. Salinity was significantly different as concentrations increased. Since C. pepo L. could withstand salinity levels of upto70 mM with germination of up to 47%, farmers within saline areas or those who use irrigation water should use water that has a salinity concentration that is not beyond 70mM.