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Morphology
Mung bean (Vigna radiata) is a species of Fabaceae plant which is also known as green gram. It is sometimes confused with black gram (Vigna mungo) for their similar morphology, though they are two different species. The green gram is an annual vine with yellow flowers and fuzzy brown pods. There are three subgroups of Vigna radiata, including one cultivated (Vigna radiata subsp. radiata) and two wild ones (Vigna radiata subsp. Sublobata and Vigna radiata subsp. glabra). It has a height of about 15-125 cm. Mung bean has a well-developed root system. The lateral roots are many and slender, with root nodules grown. Stems are much branched, sometimes twining at the tips. Young stems are purple or green, and mature stems are grayish yellow or brown. They can be divided into erect cespitose, semi-trailing and trailing types. Wild types tend to be prostrate while cultivated types are more erect. Leaves are ovoid or broad-ovoid, cotyledons die after emergence, and ternate leaves are produced on two single leaves. The leaves are 6-12 cm long and 5-10 cm wide. Racemes with yellow flowers are borne in the axils and tips of the leaves, with 10-25 flowers per pedicel, self-pollinated. The fruits are elongated cylindrical or flat cylindrical pods, usually 30-50 per plant. The pods are 5-10 cm long and 0.4-0.6 cm wide and contain 12-14 septum-separated seeds, which are green, yellow, brown and blue and can be cylindrical or spherical in shape. Seed colors and presence or absence of a rough layer are used to distinguish different types of mung bean.

Germination
Typically within 4-5 days, but the actual rate of germination varies according to the amount of moisture introduced during the germination stage. Epigeal with the stem and cotyledons emerging from the seedbed.

Post-germination
The seed splits, and a soft, whitish root grows. Bean sprouts are harvested during this stage. If not harvested, it develops a root system, then a green stem which contains two leaves shoots up from the soil. After that, seed pods begin to form on its branches, with 10-15 seeds contained in each pod.

Maturation
The maturation can take up to 60 days. Once matured, it can reach up to 30 inches tall, with multiple branches with seed pods. Most of the seed pods become darker, while some remain green.

Nutritional value
Mung beans are recognized for its high nutritive value. Mung beans contain about 55%-65% carbohydrate (equal to 630 g/kg dry weight) and are rich in protein, fat, vitamins and minerals. It is composed of about 20%-50% protein of total dry weight, among which globulin (60%) and albumin (25%) are the primary storage proteins (see table). Mung bean is considered to be a substantive source of dietary proteins. The proteolytic cleavage of these proteins are even higher during sprouting. Mung bean carbohydrates are easily digestible, which causes less flatulence in human compared to other forms of legumes. Both seeds and sprouts of mung bean produce lower calories compared to other cereals, which makes it more attractive to obesity and diabetic individuals.

Nitrogen fixation and cover crop
As a legume plant, mung bean is in symbiotic association with Rhizobia which enables it to fix atmospheric nitrogen (58-109 kg per ha mung bean). It can provide large amounts of biomass (7.16 t biomass/ha) and Nitrogen to the soil (ranging from 30 to 251 kg/ha). The nitrogen fixation ability not only enables it to meet its own nitrogen requirement, but also benefit the succeeding crops. It can be used as a cover crop before or after cereal crops in rotation, which makes a good green manure.

Market
Mung bean plants have a long history of being consumed by humans. The main consumed parts are the seeds and sprouts. The mature seeds provide an invaluable source of digestible protein for humans in places where meat is lacking or where people are mostly vegetarian. Mung bean has a large market in Asia (India, Southeast-Asia and East Asia) and is also consumed in Southern Europe and in the Southern USA. Mung bean protein is considered safe as a novel food (NF) pursuant to Regulation (EU) 2015/2283. The consumption of mung bean varies depending on the geographic region. For instance, in India, mung bean is used in sweets, snacks and savoury items. In other parts of Asia, it is used in cakes, sprouts, noodles and soups. In Europe and America, it is mainly used as fresh bean sprouts. The consumption of mung beans as such in the US is in the order of 22–29 g/capita per year, while the consumption in some areas of Asia can be as high as 2 kg/capita per year.

Mung bean is considered an alternative crop in many regions, which is generally preferable to sign a contract for the growing process before planting. In the US, the average price of mung bean is around $0.20 per pound. This is double the price of soybeans. The difference in production costs for mung bean and soybean is the post-harvest cleaning and/or transportation. Overall, mung bean is considered to have market potential for their drought tolerance, and they are a food crop and not a feed crop, which can help buffer the economic risk from variability in commodity crop prices for the farmers.