Fruit is a structure which arises from an ovary or fusion of several ovaries after fertilization and may or may not carry associated floral parts. Fruit formation is an evolutionary mechanism designed to support and dispersal of seed by various agencies.With few exceptions e.g. banana, it is necessary for the flowers to be fertilized to set fruit. Fruit set succeeds the process which involves fusion of male and female gametes inside the ovary and is called fertilization. Fruit setting has long been remained a major problem as is evident from the old Greek literature and wall paintings where male panicles of date palm were being rubbed againstthe female flowers to get good fruit set. Lack of pollination with compatible source leads to the flowers drop except the flowers which set parthenocarpically. Further if fertilization is affected even then the flower drop and this decision depends upon the internal hormonal levels of the plant and prevailing climatic conditions.On the basis of pollination requirement fruit plants can be autogamous, allogamous or geitonogamous. In case of fruit plants like grape, peach where pollen produced by the same flower affect the fertilization are called autogamous and fruits like apple, kiwi, pistachio necessarily require pollen produced on some other plant or cultivar which are compatible can affect fertilization are called allogamous. Another condition exists where pollen grains from the same plant affect fertilization in flower at different part of the plant e.g. Walnut, pecan nut and is called geitonogamy. Similarly on the basis of compatibility between pollen and stigma, plants can be self unfruitfull, partially self fruitfull and self fruitfull.Self fruitfulness indicates that fruit species or cultivars produce abundant viable pollen grains whose shedding coincides with the receptivity of stigma, pollination is effective and there are no pre and post fertilization barriers. However, partial self fruitfulness and self un-fruitfulness exhibits number of causes. In case of fully self fruitfull types, a solid block of a single cultivar can be raised without making any provision for cross pollination, however it has been reported that provision of cross pollination in autoganmous crops increases the fruit-set. In case of self unfruitful and partially self unfruitful types, provision of cross pollination is necessary to get the fruits. Proper selection of the cultivars is therefore important from the point of fruit yield for which besides overlapping of blossoming season over long periods, the time of maturity, productiveness, market values etc. are of importance. Pollenizer must be a heavy pollen producer to ensure better chances of cross fertilization. Although pollenizers are desirable, their number must be restricted so that these do not become uneconomical because the pollenizer trees occupy space, consume nutrition and take away attention of the fruit grower without any return in yield, which would have otherwise been diverted to the trees capable of bearing fruits.