Title: Effects of different concentrations of zinc on chlorophyll, starch, soluble sugars and proline content in Cucurbita pepo
Abstract: Naked pumpkin (Cucurbita pepo) is planted as a medicinal plant in Iran. This herb is effective against prostate cancer and its seeds are a rich source of zinc. It has been demonstrated anti-parasitic and anti-fungal effects. Zinc is one of the micronutrients essential for plant growth and development. In addition, zinc is a heavy metal and too much zinc can cause toxicity in most plants. Currently, environmental pollution, especially pollution from heavy metals due to industrial activities and indiscriminate use of chemical fertilizers cause irreparable damage to the plants. In this study examined the effect of different concentrations of Zn2+ [control (zero), 30, 60, 90, 120 and 150 mM] on chlorophyll a, chlorophyll b, starch, soluble sugars and proline in naked pumpkin (Cucurbita pepo). Plants were treated for 14 days and after this time will be tested. Experimental design was a completely randomized design with four repetitions. Data were analyzed using software Mstatc, Spss and Excel and mean comparisons were performed using the least significant difference test (LSD). The results showed that that high zinc concentrations decrease of photosynthetic pigments such as chlorophyll a and chlorophyll b. However, soluble sugars and proline increased. These compounds are used in various stress for osmotic adjustment, preserve the enzymes and membranes in plant cells. Reduced starch is related to degrade it to soluble sugars. Correlations between traits showed a positive correlation exists between photosynthetic pigments and starch and their correlation with soluble sugar and proline is negative. * Corresponding Author: Farshad Sorkhi Lalelou [email protected]