Cropping System

A system is defined as any set of interrelated elements which interact among themselves to operate together for its function. Equivalently, the exploitation and management of a cropping pattern to obtain maximum benefits from a given resource under a specific environmental condition is called a cropping system. In principle, cropping systems are the manipulation of all resources viz. land, water, and solar radiation for efficient utilization to maintain stability in production and obtain higher net returns. The efficiency of a cropping system is measured by the quantity of produce obtained per unit resource in a unit of time.

Cropping intensity is a practice adopted by farmers to increase their income from the piece of land that they possess. It is defined as the number of crops grown in the piece of land in one crop calendar.

CI = No. of crops grown in one agriculture year in a field × 100

Or, it can also be calculated as:

CI = (Gross area of crop sown / Net area of the field) × 100

At present, the average cropping intensity in India is about 140%, and the average CI for Assam for the past decade is ~146.5%.

• Mono Cropping: A system of growing the same crop on the same land year after year. In this type of cropping system, the cropping intensity is 100% (Fig. 1).

  Multiple Cropping: Growing two or more crops on the same field in a year. It is the intensification of the cropping system concerning time and space i.e. larger number of crops in a year on the same piece of land at any given period. Multiple cropping can be practiced by either inter-cropping, mixed cropping, sequential or sequence or non-overlapping cropping, and relay or overlapping cropping.

  

  Figure 1: Monocropping: Maize field

• Intercropping: Growing two or more crops simultaneously on the same piece of land with a definite row arrangement or in a fixed ratio is called intercropping e.g., wheat and mustard grown at a ratio of 9:1. Here, the cropping intensity in the space dimension is achieved. In this kind of cropping pattern, large row intervals between crops are maintained to accommodate the other crop. Intercropping can be done through alley cropping, strip cropping, contour cropping, paired row cropping, skip cropping, parallel cropping, etc. Some of the major intercropping systems that are widely followed are:

• Parallel Cropping: In this kind of cropping system, crops that have different growth habits and have zero competition between them are grown parallelly in the field at the same time. For example, Black gram/ Green gram is grown parallelly along with Maize as, the peak nutrient demand period for urad or mung (black/green gram) is around 30-35 days after sowing (DAS) whereas, it is 50 DAS for Maize. Therefore, competition for nutrient absorption between the two crops is minimal making them favorable for parallel cropping.

  

  Figure 2: Parallel intercropping: Maize and beans intercropping at 1:1 ration

• Companion Cropping: In such intercropping system, the production of both the intercrops as well as the main crop is equal to when it is grown as individual pure/solid crops or when grown together at the same time in the same field. E.g. Mustard/, Potato or Onion + sugarcane. The growing of the above three intercrops as individuals or together with sugarcane hardly affects its yield.

• Multistoreyed/Multitier/Multilevel Intercropping: Cultivation of two or more crops of different heights simultaneously on a certain piece of land. E.g. coconut + turmeric + pineapple
• Synergetic Cropping: In this kind of cropping system, the yield of both the crops growing together is higher than when grown separately (pure/solid) e.g. Sugarcane + Potato. Here, the intercultural/earthing up in one crop will benefit another one.
• Mixed Cropping: The cultivation of two or more crops simultaneously on the same land without a definite row pattern or fixed ratio is called mixed cropping. In this system, the seeds are generally sown by broadcasting methods. This kind of cropping pattern is commonly practiced in dryland areas of India. It is subsistence farming, for one’s own use with little or no surplus for trade. Its main objective is to lessen the risk of total crop failures and to satisfy the needs of farmers for food and fodder.

• Sequence/Sequential Cropping: Growing two or more crops in quick succession on the same piece of land in a farming year is called sequence/sequential cropping. The sowing of the succeeding crop and harvesting of the preceding crop may be done simultaneously or in quick succession e.g. just after the harvesting of maize, potato is sown, and just after harvesting potato, chili is sown. Sequential cropping is also called non - overlapping cropping because there is no overlap between the two or more cropping. Ratooning or Ratoon cropping can also be classified under sequential cropping.

  

  Figure 3: Multistoried intercropping of coconut, turmeric and pineapple

• Relay Cropping: Its concept has been derived from a relay race in which two or more runners run in the field having a baton in their hand. The first runner passes on his/her baton to the succeeding partner and 2nd to 3rd and 3rd, to the 4th runner, and so on. Relay cropping can be defined as growing two or more crops simultaneously during the part of the life cycle of each. Succeeding crops are planted/seeded before harvesting the preceding crop. Generally, the crop is planted after the first crop has reached its reproductive stage but before it is ready for harvest.

Diversification and intensification of rice-based cropping systems with remunerative and efficient crops like pulses, oilseeds, and vegetables have great scope to generate maximum profit and improve soil health. A diversified cropping pattern is seen to be the most popular strategy adopted by farmers to gain higher profit and eradicate the risks of price fluctuation and production failure. In recent years, the farmers of Assam have started growing different rabi crops including cereals, pulses, oilseeds, potatoes, and vegetables in a sequence that helps in increasing the cropping intensity of the state as well as the farmers’ income.

Existing cropping systems in Assam

Cropping seasons in Assam are distributed into three main periods, i.e. kharif, rabi and zaid. In kharif season, also known as Sali or winter season, spanning from June to November, rice is the major crop. In rabi season, also called Boro or summer season, rice is grown between November to May under assured irrigated facilities. The zaid season, also called as Ahu or autumn season extends from February to June. Many parts of the state remain flooded during the monsoon months, and farmers have very limited choice to raise alternate crops other than rice. The state has considerable potential for agricultural growth by increasing the cropping intensity, agricultural productivity, and diversification of crops. The areas under monocropping and double cropping could quickly be brought to the next level of double and triple crops, respectively, in the region.

The most prevalent cropping systems in Assam are rice-fallow, rice-potato, rice-pulses, rice-rice, rice-mustard, rice-maize, rice-vegetables, fallow-rice, among others. The rice-fallow areas (~ 1 million ha) with sufficient moisture and other suitable criteria can be targeted to increase cropping intensity and agricultural productivity of the state. This can be further expanded to three crops a year by introducing cropping cycles such as, rice-potato-rice, rice-mustard-rice, rice-maize-rice, rice-pulse-rice (Fig. 1).