Studies on fruit morphology, nutritional and floral diversity in less-known melons ( Cucumis melo L.) of India

Less-known melons belonging to the genus Cucumis melo L. were studied for the Indian region. A total of 39 accessions of distinct types in less-known melons, C. melo subsp. agrestis var. agrestis (local names-‘choti kachri’, ‘badi kachri’, ‘sukkangai’), C. melo subsp. agrestis var. momordica (‘phunt’, ‘vellari’; snap melon), C. melo subsp . agrestis var. conomon (‘sohthiar’; oriental pickling melon), C. melo subsp. melo var. flexuosus (‘kakdi’, ‘tar’; snake melon) and C. melo subsp. agrestis var. alwarensis (‘arya’) were studied for morphological characters of fruit to identify their genetic resource value. Out of 39 accessions, four taxa were selected for nutritional analysis and the floral diversity study on the basis of research gaps, status of diversity in wild and vulnerability in cultivation, and non-availability of comparative account in the context of diversity in the Indian region. Nutritional components of 12 accessions of four taxa-‘choti kachri’ and ‘badi kachri’, snap melon, snake melon and ‘arya’ were analyzed. Additionally, the floral diversity traits were studied to support marker characters and to classify the subspecies under the respective botanical varieties and cultivar delimitation. Morphologically ‘choti kachri’ and ‘badi kachri’ were identical except for the fruit size and weight; arya and snake melon grouped together with snap melon and other intermediate forms; oriental pickling melon was entirely distinct, more closer to the musk melon but had no fruit aroma. Based on floral diversity study, ‘choti kachri’ and ‘badi kachri’ were grouped together whereas snake melon and ‘arya’ were closer and snap melon showed intermediary position. The result of the nutritional analysis clearly demonstrated variability recorded among accessions for all proximate traits in ‘choti kachri (IC629817) which had the highest proteins (2.16–3.67%), ash content (3.059%), crude fat (0.482%), dietary fibre (4.12%), starch content (3.50%), Fe (4.06 mg/100 g), Zn (1.498 mg/100 g), total phenols (29.5%) and ascorbic acid (25.9 mg/100 g) among the studied melon accessions. On the other hand, ‘badi kachri’ (IC629828) had the least protein, crude fat, Cu, Fe, total phenol and ascorbic acid contents followed by snap melon, snake melon and ‘arya’ with moderate to low values of all nutritive traits. The study would facilitate identification of the distinct morphotypes in each category and grouping the intermediate type and unknown taxa. Fruit nutritional analysis will help in using them for desirable nutritional traits for pre-breeding programmes. Besides, the floral diversity can lead to identification of marker characters in crop improvement programme.