Intercropping to alleviate food scarcity in changing climate
November 2nd, 2015 | By M. Javaid Akhter, M. Ahmed Waqas, M. Rizwan, and Riaz Ahmad | No Comments
FOOD CONTAINS essential body nutrients such as carbohydrates, fats, proteins, vitamins or minerals that is ingested and assimilated by an organism to produce energy, stimulate growth and maintain life. Main sources of food are animal, plants, birds and fishes. Field crops (wheat, rice, maize, barley, millet etc.) which use as food are cereals, leguminous and oilseed crops. As the world population, a pressure is increasing day by day. So, we should change our approach by increasing the area under cultivation and yield per unit area. The first solution is not much practically applicable in the present scenario of the world population. Thats why; we have to move on the second option. Yield per unit area can be augmented by cultivating high yielding varieties, use of agrochemicals and intake of intercropping in our cropping system.
Intercropping is the agricultural practice of cultivating two or more crops in the same space at the same time and practiced mostly on small farms with limited resources, it comes under the umbrella of vertical agriculture approach. The most important benefit of intercropping is to produce a greater yield per unit area by using resources efficiently. Intercropping expressed in terms of Land Equivalent Ratio (LER) which shows the ratio of the area under sole cropping to the area under intercropping needed to give equal amounts of yield at the same management level, it is the sum of the fractions of the intercropped yields divided by the sole-crop yields. When the LER is more than one the intercropping favors the yield, while when the LER is less than one the intercropping negatively influences the yield of crop grown in mixtures.
There are several types of intercropping. Row intercropping, growing two or more crops at the same time with at least one crop planted in rows. Strip intercropping, raising two or more crops mixture in strips and wide enough to allow separate crop production using machines but narrow enough for the crops to interact. Mixed intercropping, growing two or more crops in mixture with no separate row arrangement. Relay intercropping, growing a second crop in a standing crop before harvesting when the standing crop is at its reproductive stage.
In different parts of the world intercropping is being practiced which provide as much as 15-20% of the worlds food supply. In tropical areas intercropping is mostly associated with food production. In Latin America, farmers grow 70-90% of their beans with corn, potatoes, and other crops. In Africa, 89% of cowpeas are intercropped, while 90% of beans are intercropped in Colombia. UN World Food Program analyzed that more than 800 million people around the world go hungry daily. Food security is a distressing danger of world, by adopting intercropping we enhance yield per unit which directly influences on food security. Intercropping can increase yield and solve food issue through following ways.
Intercropping encourages efficient resource utilization and yield advantage by escalating growth resources such as light, water, and nutrients. It also enhances the nutrients uptake, gave better rooting ability and increased water use efficiency too much extent, e.g. maize-cowpea and maize-beans increase light interception, reduce water evaporation and improve conservation of the soil moisture than with maize alone.
Intercropping is more adventitious than mono-cropping as stability under intercropping may be due to the partial restoration of the range that is missing under mono-cropping. So, intercropping provides more cover against crop failure, especially in extreme weather conditions such as flood, drought and overall gave more financial solidity for farmers and suitable for labor-intensive small farms. If one crop fails due to any risk, the component crop may still be there. Moreover, farmers may able to handle with seasonal price unpredictability of produce which over and over again can weaken their income. Intercropping also helps to control soil erosion and sustain crop production, it conserve soil from runoff, increase the yield and ultimately improve the fertility of the soil. Legumes intercropping enhance the fertility status of the soil. Legumes supplement soil by fixing the atmospheric nitrogen and make available for plant uptake. When nitrogen fertilizer is restricted in supply, biological nitrogen fixation is an important source of nitrogen in legume-cereal cropping systems.
Excessive rainfall becomes the cause of high soil erosion attributed to runoff, eventually consequential in infertile soils with a poor character for crop production. Intercropping of sorghum-cowpea condensed runoff by 20-30% than with sorghum sole crop and soil loss was decreased with intercropping by more than 50% compared with sorghum monoculture.
Intercropping is an effective tool against lodging for some crops. The ability of crops to remain standing is predominantly important because lodged crops may unable to photosynthesize, translocate nutrients and hence yield will less. Crop lodging interferes with harvesting operations or causes harvest loss. Intercropping provides well again lodging, improved stability, good crop quality ultimately enhanced the efficiency of harvest. Intercropping of Canola or mustard also significantly improves the lodging resistance of grain legumes and hence enhancing yield, produce quality and harvest efficiency. Pea intercrop with oat also trims down lodging because oat gave support to pea and also provides a wind barrier against erosion.
Significant incidence of pests and diseases reduce by intercropping, component crops are not as much affected as sole crops. Crops grown in mixture increase the profusion of predators and parasites, which ultimately put off the build-up of pests, thus decreasing the need of using costly and unsafe chemical insecticides. Intercropping modifies environmental conditions in such a way that they are less favorable to the spread of some pathogens. Compared to sole crop, the population of natural enemies of pests is high in the intercrop. It also ensures better weed management attributed to developed crop canopy of component crops.
Adopting intercropping all these benefit could be obtained which is not possible by sole cropping and hence food production can be appreciably enlarged, as in intercropped crops productivity per unit area is superior than sole cropping, with the similar level of supervision and yield benefits can range from 20% to 60% attributed to lessening of pest attack and more resourceful usage of water, nutrients and solar radiation. Intercropping upholds biodiversity, prosper devoid of agrochemicals, and sustain yields year after year. So, while intercropping has been used conventionally for thousands of years and is prevalent in several parts of the globe, it is still feebly unspoken from an agronomic point of view and research in this area is remote less superior than as good as exertion in monoculture.
Published in: Volume 06 Issue 44
Short Link: https://www.technologytimes.pk/?p=14659