~ 2631 ~ International Journal of Chemical Studies 2018; 6(5): 2631-2634 P-ISSN: 2349–8528 E-ISSN: 2321–4902 IJCS 2018; 6(5): 2631-2634 © 2018 IJCS Received: 15-07-2018 Accepted: 20-08-2018 Meenakshi S Doddamani Department of Biotechnology and Crop Improvement, KRCCH, Arabhavi, UHS Bagalkot, Karnataka, India Satish D Department of Biotechnology and Crop Improvement, KRCCH, Arabhavi, UHS Bagalkot, Karnataka, India Sandyarani Nishani Department of Biotechnology and Crop Improvement, KRCCH, Arabhavi, UHS Bagalkot, Karnataka, India Dileepkumar A Masuthi Department of Biotechnology and Crop Improvement, KRCCH, Arabhavi, UHS Bagalkot, Karnataka, India Seetaramu GK Department of Floriculture, KRCCH, Arabhavi, UHS Bagalkot, Karnataka, India MH Tatagar Department of Entomology, KRCCH, Arabhavi, UHS Bagalkot, Karnataka, India Correspondence Meenakshi S Doddamani Department of Biotechnology and Crop Improvement, KRCCH, Arabhavi, UHS Bagalkot, Karnataka, India Estimation of genetic diversity in local collections of cucumber ( Cucumis sativus L . ) Genotypes based on productivity traits Meenakshi S Doddamani, Satish D, Sandyarani Nishani, Dileepkumar A Masuthi, Seetaramu GK and MH Tatagar Abstract A field experiment was undertaken during the year 2017-2018 in kharif season at Kittur Rani Channamma College of Horticulture, Arabhavi to study the extent of genetic diversity existing in local cucumber collections. The experiment was laid out in randomized block designs with two replications. A total of 21 local collection of cucumber genotypes were used in the present study. Mahalanobis D 2 analysis indicated considerable diversity and 21 genotypes were grouped into six different clusters. The cluster II showed maximum (2242.20) intra cluster distance. Inter cluster distance revealed the maximum divergence between clusters IV and cluster III (D 2 = 32489.21) followed by cluster III and cluster II (D 2 = 24315.24). Among all the 19 productivity traits studied, flesh thickness, fruit diameter, fruit length and average fruit weight contributed greatly towards divergence. These traits may give more importance in selecting the genotypes the genotype KRCCH-CC-17 in cluster V recorded highest cluster mean. This genotype can be used as a base material for future breeding programme. Keywords: estimation, genetic diversity, Cucumis sativus, productivity traits Introduction Cucumber (Cucumis sativus L.) is one of the most popular vegetable of family cucurbitaceae with chromosome number of 2n=14. It is an ideal summer vegetable crop chiefly grown for its edible tender fruits, preferred as salad ingredient, pickles and desert fruit and as a cooked vegetable. Cucumber has got cooling effect, so in the eastern countries; fruits are often used as cooling vegetable. It is ideal for people suffering from jaundice and allied diseases and also very much useful in preventing constipation. Seeds contain oil, which is helpful for brain development and body smoothness. Hence, it is being used in Ayurvedic preparations [1] . Cucumber is a highly cross pollinated crop and usually monoecious in nature preferring warm weather and bright light for its better growth and development. However, it can be grown in both summer and rainy season, but it cannot tolerate cold injury. Being primary centre of origin, India has accumulated wide range of variability in this crop. In spite of large number of varieties available in India, only few are promising. This fact draws the attention of plant breeder for its improvement. To formulate a sound and successful breeding programme, the importance of genetic variability in the population needs emphasis. To make an improvement in any crop species, the breeder is constantly engaged in effective choice of desirable parents of high genetic variation so that individuals with desirable character combination can be selected. Genetically diverse parents are likely to produce high genetic diversity effects and desirable traits tool in quantifying the degree of divergence among the biological populations. Material and Methods The present study was carried out at Kittur Rani Channamma, College of Horticuluture, Arabhavi during Kharif season in 2017-18 with 21 local collections of cucumber genotypes. The genotypes were assessed in a field experiment under a Randomized Block Design with two replications. Cultural practices including need based plant protection measures were followed as per the recommendations. The data were recorded on five randomly selected plants from each genotype for 19 traits. Observations were recorded on vine length (cm), number of leaves per vine, number of branches per vine, number of nodes per vine, node at first male flowering, node at first female flowering, days to first male flowering, days to first