Cropping systems, Cropping patterns ABT-320 Dr. Rabia Amir Lecture 6

Introduction Cropping system comprises all components required for the production of a particular crop and the interrelationships between them and environment. In the cropping systems, sometimes a number of crops are grown together or they are grown separately at short intervals in the same field. This delineates cropping patterns.

Basic Principle of cropping systems Choose crops that complement each other Choose crops and a cropping system which utilize available resources efficiently Choose crops and a cropping pattern that maintain and enhance soil fertility Choose crops which have a diversity of growth cycle Choose a diverse species of crops Keep the soil covered Strategically plan and modify the cropping system as needed

Objectives of cropping systems Efficient utilization of all resources viz. land, water, and solar radiation maintaining stability in production and obtaining higher net returns. The efficiency is measured by the quantity of produce obtained per unit resource in a unit time

Benefits of cropping systems Maintain and enhance soil fertility Enhance crop growth Minimize spread of disease Control weeds Inhibit insect and pest growth Increase soil cover Reduce risk for crop failure Use resources more efficiently

Classifications of Cropping System Depending on the resources and technology available, different types of cropping systems are adopted on farms, which are as below: Sole cropping (monoculture) Intensive cropping: Multiple cropping Intercropping Sequential cropping/Crop rotation

Monocropping Disadvantages: it is difficult to maintain cover on the soil it encourages pests, diseases and weeds it can reduce the soil fertility and damage the soil structure.

Intensive cropping Need for intensive cropping Cropping systems has to be evolved based on climate, soil and water availability for efficient use of available natural resources. The increase in population has put pressure on land to increase productivity per unit area, unit time and for unit resource used.

Multiple cropping Growing two or more crops on the same field in a year. Annual and perennial plants can be organized in fields together. It is a form of polyculture tomatoes + onions + marigold; the marigolds repel some tomato pests.

Intercropping Intercropping is the growing of two or more crops together in proximity on the same land. As a result, two or more crops are managed at the same time. It differs from crop rotation in which two or more crops are grown one after the other. There are at least four types of intercropping according to spatial arrangement (Sullivan, 2003).

Intercropping

Row intercropping Row intercropping is the growing of two or more crops at the same time with at least one crop planted in rows. In farms grown to perennial crops, annual crops like corn, rice and pineapple are commonly grown as intercrop between the rows of the main crop. This strategy is an efficient way of maximizing the use of farm land by utilizing vacant spaces while at the same time suppressing the growth of weeds during the juvenile stage of the main crop.

Row-intercropping

Strip intercropping Strip intercropping is the growing of two or more crops together in strips wide enough to allow separate production of crops using mechanical implements, but close enough for the crops to interact. Examples of successful strip intercropping practices are: alternating strips of wheat, corn and soybean 6 rows wide each; oat, corn and soybean; and 6 rows of corn with 12 rows of soybean.

Strip intercropping

Mixed intercropping Mixed intercropping or mixed cropping is the growing of two or more crops at the same time with no distinct row arrangement.

Relay intercropping Relay intercropping or relay cropping is a system in which a second crop is planted into an existing crop when it has flowered (reproductive stage) but before harvesting. There is thus a minimum temporal overlap of two or more crops. The relay crop should be fairly tolerant to shade and trampling. Examples of relay crops are cassava, cotton, sweet potato and sesban with corn; chickpea, lentil and wheat with upland rice.

Relay intercropping

FAVORITE COMBINATIONS FOR INTERcropping VEGETABLE SUGGESTED LOCATION ARUGULA between tomatoes under pole beans or trellised cucumbers BASIL between tomatoes BUSH BEANS between tomatoes, peppers, or eggplant BEETS between brassicas (broccoli, Brussels sprouts, cabbage, cauliflower), onions, leeks, or zucchini CARROTS between bush beans, leeks, or tomatoes CILANTRO between leeks LETTUCE under corn, pole beans, or tomatoes; between celery, celeriac, leeks, or brassicas ONIONS between cabbage plants (or any other member of the brassica family) PARSLEY RADISHES everywhere (they’re said to help repel pests when planted with cucumbers or squash) SPINACH under pole beans or trellised cucumbers and between leeks, turnips, and brassicas WINTER SQUASH under corn

World wide practices Examples of mixed intercropping of annual crops are the practice of growing corn, bean and squash in Central America and forage sorghum with silage corn in Oregon. In Canada, research showed increased production per land area by growing together soybean and corn for silage in the same rows.

Advantages of intercropping Better use of growth resources including light, nutrients and water Suppression of weeds Yield stability; even if one crop fails due to unforeseen situations, another crop will yield and gives income Successful intercropping gives higher equivalent yields (yield of base crop + yield of intercrop), higher cropping intensity Reduced pest and disease incidences Improvement of soil health and agro-eco system

Comparison

Crop rotation In crop rotation or sequential cropping, two or more crops are grown one after the other in the same piece of land. It is advantageous that the succeeding crop belongs to a family different from that of the previous crop. The period of crop rotation may be for two to three years or longer. Farm income significantly increased by alternating lowland rice with high-value crops like garlic, onion, melons, bell pepper and other vegetables.

Example of a Four Year Crop Rotation

Advantages of crop rotation In addition to increased crop yields and profit, the following are the advantages of crop rotation over monoculture. Better control of weeds: Crop rotation is intended to break the life cycle and suppress the growth of weeds. The sequential planting of different crops may check the development of any weed species and reduce weed growth especially if cover crops or green manures and tall-growing row crops are used as component rotation crops.

Advantages Better control of pests and diseases: Some pests and causal organisms of plant diseases are host specific. They attack certain crop species or those belonging to the same family but not others. For example, the problem with rice stem borer will continue if rice is not rotated with other crops of a different family. This is because food will be always available to the pest. However, if legume is planted as the next crop, then corn, beans and bulbs, the build up of the pest will be disrupted because they will be deprived of food.

Advantages Improved soil structure and organic matter content. The alternate planting of deep and shallow rooted plants will break up the soil. The planting of soybean, other grain legumes, sweet potato and vegetables will return sufficient quantities of plant residues to the soil as their leaves drop on the ground or body parts are left on the field after harvest, instead of being burned as is commonly practiced with sugarcane. Green manures will add significant amounts of organic matter.

Advantages 4. Improved soil fertility. The continuous growing of a single crop will result to the depletion of certain soil nutrients. With crop rotation, soil fertility will be promoted through alternate planting of crops having different nutrient needs. This will prevent the depletion of any one essential element present in the soil. Leguminous plants, because of their ability to accumulate nitrogen by fixing it from the air in association with Rhizobium bacteria, will improve soil fertility.

Thank You !