AGRICULTURAL WATER MANAGEMENT, cilt.221, ss.150-159, 2019 (SCI-Expanded)
Climate change-associated drought stress in plants is one of the major environmental factors that cause a reduction in plant growth, development, and productivity. Therefore, an improvement to obtain superior genotypes that are highly adaptable to arid and semi-arid conditions remains the main objective of the future breeding efforts. In this context, the present study was conducted to determine the genotypic differences among 16 inbred lines and 4 commercial cultivars of pumpkin associated with the parameters such as certain fruit characteristics, seed yield, and seed quality in irrigated and drought conditions. In the growing season of pumpkin, the amount of irrigation water applied was 402.6 mm in 2017 and 425.4 mm in 2018. In all the evaluated parameters, the examined genotypes exhibited a wide range of significant differences between the irrigated and drought conditions in both the years. Moreover, a significant positive correlation was observed between seed yield and fruit number, seed-thickness and plant height, and 1000-seed weight and seed size. In terms of seed quality, 1000-seed weight was determined to be a prominent parameter. The results of the present study demonstrated that these relationships imply a significant potential for the selection of genotypes with superior performance in both conditions. Furthermore, principal component analysis (PCA), performed considering the Eigenvalues, indicated that the yield and quality components could be explained strongly by the PCA analysis in irrigated as well as in drought conditions. Finally, the inbred line G9 was observed to be the most superior genotype in terms of yield and fruit number in both irrigation and drought conditions; therefore, this inbred line is envisaged to be evaluated in future breeding studies and to be included in future hybrid programs in order to develop drought-tolerant cultivars.