Effect of various concentrations of zinc on chlorophyll, starch, soluble sugars and proline in Naked pumpkin (Cucurbita pepo) Journal title: International Journal of Farming and Allied Sciences Authors: Farshad Sorkhi lalelou, Jalil Shafagh-Kolvanagh and Mojtaba Fateh Subject(s): Agricultural Science, Biochemistry, Plant Sciences, Soil Sciences, Zoology and Animal Science, Agricultural Economics