الفهرس 
AcknowledgementsOnly 14 pages are availabe for public view
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Abstract
Vegetables play a pivotal role in human diet as they are the main source of some important supplements, especially vitamins and minerals. Summer squash is a member of the gourd family, Cucurbitaceae and is a member of the genus Cucurbita. This family is one of the biggest in the plant kingdom. Squash fruits are good for dieters due to their low – calorie content having significant amount of vitamins and minerals. Being a short duration crop the marketable produce comes earliest in the market during summer and thereby fetches relatively higher returns for the producer. It is a monoecious plant, grown for both food security and medicinal purposes. The pollens of cucurbitaceous crops are sticky, this can not be blown by wind. Therefore, pollinating agents usually bees are necessary to transfer pollen from male to female flowers. Large quantity of pollens must be delivered to a female flower if it is to set a marketable fruit. Adequate pollination results into uniform formed fruits with even maturity, while incomplete pollination results in to improperly formed small fruits. Cucurbits is an important source of carotenoids which have a biologically active substance with antioxidant. Carotenoids have an extensive list of pharmacological properties that is radioprotective, provitaminic, anticarcinogenic and other types of activity. Summer squash covers a total area of 1,000,000 hectares over the world with annual production of 19,000,000 ton. It is a cross pollinated crop having a diploid chromosome number (2n = 2x = 40) which planted for its fruits.