Common Name: Chena                                   Scientific Name:Amorphophallus paeoniifolius

Description: Amorphophallus belongs to the family Araceae.  Amorphophallus paeoniifolius, the Elephant foot yam or White spot giant arum is a tropical tuber crop that offers excellent scope for adoption in the tropical countries as a cash crop due to its production potential and popularity as a vegetable in various delicious cuisines. Elephant foot yam is basically a crop of Southeast Asian origin. It grows in wild form in Sri Lanka, the Philippines, Malaysia, Indonesia, and other Southeast Asian countries. In India it is grown mostly in Bihar, West Bengal, Kerala, Karnataka, Andhra Pradesh, Maharashtra and Orissa.

            As per Indian Medicinal Plants dictionary by C.P. Khare, published by Springer, the Elephant-foot yam has several medicinal benefits and widely used in Indian medicine including Ayuverda, Siddha and Unani. The corm is prescribed in bronchitis, asthma, abdominal pain, emesis, dysentery, enlargement of spleen, piles, elephantiasis, diseases due to vitiated blood, rheumatic swellings. Along with other therapeutic applications, The Ayurvedic Pharmacopoeia of India indicates the use of corm in prostatic hyperplasia. (The corm is irritant due to the presence of calcium oxalate. It can be consumed after it is washed well and boiled in tamarind water or butter milk.) The corm contains an active diastatic enzyme amylase, betulinic acid, tricontane, lupeol, stigmasterol, betasitosterol and its palmitate and glucose, galactose, rhamnose and xylose.

Common Name: Chembu                                                  Scientific Name: Colocasia esculenta

Description: Colocasia is a genus of 25 or more species of flowering plant in the family Araceae, native to tropical Polynesia and southeastern Asia. Common names include Elephant-ear, Taro, Cocoyam, Dasheen, Chembu, and Eddoe. They are herbaceous perennial plants with a large corm on or just below the ground surface. The leaves are large to very large, 20–150 cm (7.9–59.1in) long, with a sagittate shape. The elephant's-ear plant gets its name from the leaves, which are shaped like a large ear or shield. The plant reproduces mostly by means of rhizomes (tubers, corms) but it also produces "clusters of two to five fragrant inflorescences in the leaf axils”. Like other members of the family, the plant contains an irritant which causes intense discomfort to the lips, mouth and throat. This acridity is caused in part by microscopic needle like raphides of calcium oxalate monohydrate and in part by another chemical, probably a protease. The acridity helps to naturally deter herbivores from eating it. It must be processed by cooking, soaking or fermenting-sometimes along with an acid (lime or tamarind) before being eaten. The species is dangerously invasive into wetlands along the American Gulf coast, where it threatens to displace native wetland plants. Colocasia species are used as food plants and in Kerala the leaves and roots of the palnts are used to make various dishes. Sree Rashmi and Sree Pallavi are two improved varieties. 

Common Name: Greater Yam /Kachil                                      Scientific Name: Dioscorea alata

Description: Greater Yam is a typically tropical plant belongs to the family Dioscoreaceae. The crop cannot withstand frost and excessively high temperatures. Temperature around 300C and rainfall 120-200cm distributed throughut the growth period is ideal. Day length greater than 12 hours during initial stages and shorter day length during the later part of the growing season favor satisfactory tuber formation.  It is used in a variety of desserts, as well as a flavor for ice cream, milk, Swiss rolls and other pastries. In folk medicine it has been used as a laxative and vermifuge, and as a treatment for fever, gonorrhea, leprosy, tumors, and inflamed hemorrhoids. Different varieties include Sree Keerthi, Sree Roopa, Indu and Sree Shilpa.

Common Name: Lesser Yam/Nanakizhangu                 Scientific Name: Dioscorea esculenta

Description: Dioscorea esculenta, commonly known as the Lesser Yam, is a yam species, but with a smaller corm than most other yams. It is closer in size to a potato or sweet potato and belongs to the family Dioscoreaceae. Belonging to the genus Dioscorea, Dioscorea esculenta describes the plants ability to produce edible roots, known as yams, also known aschinese yam, as it is mostly grown in Asia. Due to the fact that it is fast going to extinction, the species is known as hungry yam amongagronomists. Different varieties include Sree Latha and Sree Kala.

Common Name: White  Yam                                           Scientific Name: Dioscorea rotundata

Description: White yam or African yam is a new crop species of edible yam introduced from Nigeria, which belongs to the family Dioscoreaceae. A vine with a cylindrical stem, twining to the right, usually spiny and with dark glossy green leaves. Tubers usually weigh 2-5 kg, on good sites they can be up to 10 kg and 20-25 kg have been recorded. The tubers are however hard and unpalatable if harvested prematurely. Tubers have a definite dormant period. The species is indigenous to West Africa. Mentioned as a useful agro forestry species. Varieties inclide Sree Subhra, Sree Priya and Sree Dhanya.

Common Name: Sweet Potato/ Madhurakizhangu                Scientific Name: Ipomea batatas

Description: The sweet potato is a dicotyledonous plant that belongs to the family Convolvulaceae.  Tuberous-rooted perennial, usually grown as an annual; top herbaceous, drying back to ground each year; stems forming a running vine up to 4 m long, usually prostrate and slender, with milky juice, lateral stem-branches arising from the short stem and usually not branched; leaves ovate-cordate, borne on long petioles, palmately veined, angular or lobed, depending on variety, green or purplish; flowers white or pale violet, axillary, funnel-shaped, borne singly or in cymes on short peduncles; pods round; seeds 1-4 per pod, flattened, hard-coated, angular. The crop is native to the American Tropics. Sweet potato requires a warm humid tropical climate with a mean temperature of about 22ºC.  Although the leaves and shoots are also edible, the starchy tuberous roots are by far the most important product. In some tropicalareas, they are a staple food crop.

Common Name: Tapioca/ Cassava/ Maruchini                Scientific Name: Manihot esculenta

Description: Tapioca belongs to the family Euphorbiaceous. Tapioca grows and produces best under warm humid tropical conditions where rainfall is well distributed and fairly abundant. It can also be grown under irrigation where rainfall is low. Its outstanding characteristic in terms of moisture requirements is the ability to withstand fairly prolonged periods of drought. However, at the time of planting there must be sufficient moisture for the plant to establish itself. The crop cannot withstand cold and is killed by frost. The crop grows well in well-drained laterite, gravelly and sandy loam soils. Heavy and rocky soils are less suitable because they restrict root development. The crop cannot survive waterlogged conditions and in such areas, it must be planted on mounds or ridges that permit drainage. The crop can also be gown on hill slopes and on wastelands of low fertility.