Horny gourd (Cucumis metuliferus L.): a hidden vegetable boon for human nutrition

Abstract

The Horny gourd or Horn gourd (Cucumis metuliferus L.) is an under utilized vegetable crop, which is neither grown commercially on large scale nor traded widely. It has drawn less attention due to their poor agronomical traits like thorns and high seed content. However, it has good sources of vitamins, minerals, trace elements, dietary fibre and proteins and serve to be genetic sources for multiple biotic and abiotic stress. It grows at an altitude of 210 m to as high as 1800 m above sea level. It is herbaceous plant able to climb by cirrus (tendril) opposite to the leaves; plant is a monoecious sex forming type, climbing annual with staminate flowers typically appearing before pistillate flowers. The fruit is oblong-cylindrical, with an average length of about 12 cm and a diameter of about 8 cm, green when it is unripe, it takes on a colour orange yellow when mature, covered with strong spiny outgrowths (short, stout cucumber with many blunt thorns). The mesocarp is green and consists of juicy, bland-tasting tissue, sprinkled with translucent white seeds about 5 to 9 mm long, edible, ellipsoid, flattened, and there are hundreds per fruit. It is a reservoir of potentially useful nutritional traits and agronomical traits like resistant to Downey mildew disease, which could be useful for genetic improvement of melons.