Having seen so many cultivars of Cucurbita maxima, C. moschata and C. pepo in California, and common names pumpkin, squash and gourd being so interchangeably used for any of these, I found the same confusion regarding Indian names Petha, kaddu and others being used in local markets. For one I am happy that the key based on the tip of fruiting pedicel is very satisfactory in differentiating the fruiting specimens, although leaves and flowers may not be that reliable. For example in most sample Cucurbita moschata calyx lobes are foliaceous in specimens that I have seen in India, they are rarely so in most cultivars in USA.
Yesterday I uploaded photographs of Cucurbita moschata from India sold as Kaddu, whose plants were earlier uploaded by Balkar i as Cucurbita pepo but it turned out to be C. moschata
The comments yesterday by Ushadi about Kaddu fruits uploaded by me prompted me to make a revisit to the Keshavpur Sabzi mandi in our neinghbourhood (a big mandi in West Delhi) today morning. Luckily I could locate all the three types of so called petha in the market. One is very distinct especially when you attach Agra before it, the Ash gourd or white pumpkin, commonly used for making sweet.
The other two though quite distinct seemed to be more confusing to the sellers. More than ninety percent sellers called them petha or kaddu, and one being the younger stage and other the ripe stage of fruit, but finally one person knew them well: one which can last for more than a month (Cucurbita moschata), and another which has to be consumed within few days (Cucurbita pepo)
Cucurbita moschata: Halwa kaddu, kashi phal, mitha kadu, petha-The fruit is generally large, reaching 50 cm in length, nearly oblong, sking turning yellowish brown when mature, typical C. moschata constricted pad below fruit, flesh yellow. This plant was uploaded by me yesterday. Cooked as vegetable but with slightly sweeter taste, more commonly made into halwa. I had uploaded this yesterday. I am doing it again for comparison. Fruit purchased can be kept for more than a month without getting spoilt.
Cucurbita pepo: Gol kaddu, safed kaddu, Villaiti kadu, petha, Kadddu pumpkin: The fruit is some what depressed to nearly rounded, 20-30 cm across, pedicel tip with closely attached proecting finger, colour green with yellowish patches, flesh is pale yellowish white or greenish white. Commonly cooked as vegetable. The fruit generally plucked when not fully ripe does not last long.
I am still looking for another Kaddu from India the Red gourd, mitha kaddu, Sita Phal but as Cucurbita maxima and not C. moschata. I hope some one will upload from India in this episode.

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Gurcharan Singh