Classification of Crops in Agriculture

The crops have been classified on the basis of range of cultivation, season in which they are grown, duration of crop season, taxonomy and their uses. In this article we have discussed Classification of Crops based on season, life cycle and use plant and their product

Classification of Crops based on Season

Different annual field crops are grown in different seasons of the year. Based on the season during which they are grown, crops can be classified in three groups:

1-Kharif / rainy season crops:

Crops grown during the main monsoon season (June-July to September- October) are known as kharif or rainy season crops. Kharif crops require warm and wet weather during growth and development and shorter day-length for flowering. Rice, maize, sorghum, bajra, groundnut, til, urd, moong, cowpea, arhar, jute, soybean, cotton etc. are common examples of kharif crops.

2-Rabi/winter season crops:

Crops that require cold and dry weather for their growth and development are called rabi or winter-season crops. These crops require longer day-length for flowering. They are sown in October- November and harvested in March- April. Common rabi crops are wheat, barley, oat, gram, peas, lentil, mustard, linseed, safflower, potato etc. c. Zaid / summer season crops: The crops sown in February-March and harvested in May-June are known as zaid crops. They require hot and dry climate for their major growth and longer day-length for flowering. Urd, moong, groundnut and sesame etc. are also grown in zaid season.

However, with the production of photo and thermo-insensitive varieties of crops, seasonal classification became less relevant. The varieties of maize, rice, pulses, groundnut, til and sunflower insensitive to temperature and photoperiod can be grown in any season of the year.

Classification of Crops Based On Life Cycle

Crop plants complete their life-cycle after passing through progressive stages of development during certain period of time. Accordingly, crops are grouped into three categories:

1-Annual crops:

Crops that complete their life-cycle within a season or a year are called annual crops. These are rice, wheat, maize, mustard and tobacco. Most of field crops are annual in nature. They produce seeds within a season or year and die.

2-Biennial crops :

Crop plants that complete their life-cycle in two successive seasons or 2 consecutive live years are referred to as biennial crops. In the first year they produce leaves and store food and in the second year they produce fruits and seeds, after which the plant dies. Cabbage, radish, carrot, sugarbeet etc. are example of biennial crops.

3-Perennial crops:

The plants that live for three or more crop seasons are termed perennial crops. These plants may by seed bearing or non-seed bearing. They may propagate by seed or by vegetative propagules that may be developed in aerial, subaerial or in both parts, such as sugarcane, lucerne, napier grass, ginger and sweet potato etc.

Classification of Crops based on Use of Crop Plants and their Products

The crop plants can be predominantly used for a particular purpose. Therefore they have been classified into different groups:

A-Cereals:

Cereals are the crop plants belonging to the grass family, Poaceae. These are grown for their edible starchy seed or grain (one-seeded fruit known as caryopsis). The important grain crops used as staple food are cereals such as rice, wheat and barley.

B-Millet:

Small-grain cereals that are of minor importance as food are known as millets. There are two types of millets as large-grain millet and small-grain millet, e.g. pearl millet and ragi respectively. Millets are also used as staple food in drier regions of developing countries. As the nutrient and water requirements of millets are low, they are grown on marginally fertile and unirrigated lands.

C-Oilseeds:

Crops from which oil can be extracted are known as oilseed crops. Groundnut, sesame, mustard, sunflower, safflower, castor and linseed are the main oilseed crops.

D-Pulses:

The legumenous plants that bear edible pod are known as pulse crops. The seeds on splitting produce dal, which are rich in protein. For instance, greengram, blackgram, Bengalgram, cowpea, pigeonpea, lentil, moth, rajma etc. are pulses.

E-Forage crops :

These are used as feed for animals, fresh or preserved. The feed can be in the form of hay, silage, soilage, pasture or fodder. Forage crops are lucerne, berseem, anjan grass, dinanath grass, field bean, cowpea, napier grass, maize, oat, stylosanthus, sudan grass etc.

F-Fibre crops :

Crop plants grown to produce fibres are referred to as fibre crops. These are cotton, jute, mesta, sunnhemp, flex, agave, pineapple remi, sisal etc.

G-Sugar crops:

These crops are grown for the production of sugar, e.g. sugarcane, sugarbeet.

H-Medicinal crops :

These crops are used for preparation of medicines, e.g. opium poppy, tobacco and mint.

I-Beverages:

Products of crops used for mild, agreeable and stimulating liquors meant for drinking, such as tea, coffee and cocoa, are called beverage crops.

Special-purpose Crops

Crop plants grown for other purposes in addition to obtaining yield to meet a particular use are grouped into special purpose crops :

A-Cash crops:

These crop plants are grown for sale to earn cash. The processing of such crops after harvest is beyond the means of individual farmer. Jute, cotton, tobacco and sugarcane are grouped as cash crops.

B-Green-manure crops :

These crop plants are grown to be incorporated into the soil to improve fertility of soil. Sunnhemp and dhaincha are generally grown for green-manuring.

C-Cover crops:

These crop plants are able to minimize soil erosion from wind or water or both through covering the ground surface with their foliage, e.g. blackgram, groundnut. cowpea and

D-Smother crops:

These crop plants produce heavy foliage, which suppress the population and growth of weeds by curtailing the movement of air and radiation. Mustard, cowpea etc. are good examples of smothering crops.

E-Catch crops :

These are also known as emergency crops or contingency crops. These are cultivated to catch the forthcoming season. They replace a major crop that has failed due to biotic, climatic or management hazards. They are generally quick growing crops. Greengram, blackgram, cowpea, bajra, sunflower and toria may be grown as catch crops.

F-Mulch crops :

These crops are grown to conserve soil moisture from bare ground by their thick and multi- layered foliage, e.g. cowpea and cluster bean.

G-Trap crops:

These crop plants are grown to trap soil-borne harmful biotic agents, e.g. parasitic weed Orobanche and striga, e.g. solanaceous crops and sorghum respectively. These weed seeds germinate when they come in contact with roots of these crop plants. Thereafter the destruction of these crops reduce the inoculum of such parasitic weeds.

H-Augmenting crops:

When subcrops are sown to supplement the yield of main crops, these crops are known as augmenting crops. Japanese – mustard in berseem, and Chinese cabbage in mustard are augmenting = crops.

I-Alley crops:

When arable crops are grown in alleys formed by trees or shrubs, established mainly to increase soil productivity and reduce soil erosion, they are known as alley crops. Sweet potato, blackgram, turmeric and ginger as alley crops. When they are grown in between the rows of subabool, eucalyptus and Cassia, these crops form a component of agro-forestry system.