**2.3 Parthenocarpy**

The discovery of parthenocarpy in cucumber has led to the development of seedless fruit in combination with gynoecious trait. Gynoecy coupled with parthenocarpy is a yield and quality related parameter and a high value vegetable crop suited for protected cultivation because these varieties do not require pollination for fruit setting. The fruits of greenhouse parthenocarpic cucumber varieties are also mild in flavor, seedless and have a thin skin that does not require peeling. Still the genetics of parthenocarpy is not well understood in cucumber which is utmost important for efficient breeding procedure. Pike and Peterson [43]; Kim et al. [44] and Jat et al. [38] suggested that an incomplete dominant gene is responsible for parthenocarpic fruit development. Single recessive gene is responsible for parthenocarpy in cucumber [45]. The growing environmental conditions and epistatic interactions influence the parthenocarpy trait [46, 47] and two additive dominant epistatic major genes and additive dominant polygenes [35]. Seven QTLs for parthenocarpy were detected on chromosome 5 and 7 (*parth5.1* and *parth7.1*) and two on chromosome 6 (*parth6.1* and *parth6.2*) [48]. One major effect QTL (parth 2.1) was identified controlling parthenocarpy [49, 50]. The identification of QTLs is a valuable resource for cucumber breeders for development of parthenocarpic cultivars.
