Principles Of Crop Science Environmental Sciences Essay

The increasing population of the world has led to great issues dealing with demand and supply. This in turn leads to advancements in various scientific and cultural techniques to use the limited available resources in an effective way. The alarming issue in the recent days like urbanization, scarce area for agriculture, limited availability of resources and food security has led to development of genetically modified organisms (GMOs) to resist against pest and weeds. Among various issues coming up, this paper mainly discusses about the major crop management practices to improve crop for high yield and profit which is equally as important as GMOs.

Crop management practices

There are various methods of crop management practices, varying according to the types of resources used, climate and various other natural factors that involves the type of management to choose. Crop management involves growing crops on a massive scale, by involving methods like tillage, crop rotation, inter cropping, culling, composting, pest control and weed management, effective resources capture, irrigation techniques and hybridization. Few of the major management techniques are discussed below.

Weeds, Pests and Disease control

The European Weed Science Society defines weed as ‘any plant or vegetation, excluding fungi, interfering with the objectives or requirements of people’. Reduction of crop yield is the major reason for attempts to reduce weed population in arable crops. The first attempts at controlling weeds used manual labour and hand-hoeing which, at present days is a time consuming process. Thus a major development was the development of herbicides (Naylor, 2002).

The worldwide efficacy in controlling weed (68%) was considerably higher than the control of animal pests or diseases (39% and 32%, respectively). The continuous use of herbicide and pesticides led to the appearance of resistant biotypes of weeds and pests, playing major role in contamination of the environment [2].

In the recent days the integrated weed management (IWM) approaches plays a vital role as they incorporate multiple tactics of prevention, avoidance, monitoring and suppression of weeds, undergirded by the knowledge of agro ecosystem biology. The development of IWM was motivated by a desire to provide farmers with systematic approaches to reduce reliance upon herbicide and retard the selection of herbicide-resistant biotypes. [5]

Worldwide, pre-harvest and post-harvest losses to insects, weeds, and plant pathogens are estimated at 45 percent additional losses can be attributed to vertebrate pests. Selection of resistant varieties, rotation crops, crops for inter plantings and cover crops

is important for successful crop production with minimal inputs of chemical pesticides and fertilizers. Studies say that the use of pesticides has not solved the pest problem completely and in the past 50 years, insecticide use has increased tenfold, while crop losses from pest damage have doubled. Thus still there are studies being carried on pest control. The natural methods of control is more preferable for three major reasons like cost, safe to people and safe to environment also has no side effects. [4]

Pests and diseases impact on crop yield and quality, and also reduce resource-use efficiency. Improved crop protection strategies to prevent such damage and loss can increase production and make a substantial contribution to food security. (Advances in plant disease and pest management, J. A. LUCAS,2010)

Irrigation technique

Irrigation is the method of artificial application of water to the land or soil. It is used to assist in the growing of agricultural crops, maintenance of landscapes, and rejuvenation of disturbed soils in dry areas and during periods of inadequate rainfall. The basic principle of irrigation is to help plants on evapo-transpiration process which plays a vital role in transportation of nutrients from soil to any part of the plant. In simple words it is expressed as

More water supply More transpiration More CO2 More dry matter

More yield More Profit

There are various types of irrigation techniques varying upon the climate, nature of soil, nature of vegetation. In general, the goal is to supply the entire field uniformly with water, so that each plant has the amount of water it needs, neither too much nor too little. The earliest methods of irrigation were the perennial, basin and the terrace irrigation and the recent day’s developments were the sprinkler (gun sprinkler, portable solid-set sprinkler, pivot systems, side-roll sprinkler etc) and micro irrigation (drip irrigation). The type of irrigation technique plays a major role in the crop yield. But each irrigation systems have its own limitations and thus it is very important to choose the most suitable irrigation technique for particular variety of crop, after studying its various properties on its growth and development. For example, a study made in the western United States corn belt showed variation in the yield differing between the pivot and surface irrigation. Therefore choosing the right way of irrigation method is also an important way of crop management [3]

2.3. Resource capture

The principle of resource capture is to provide a framework through which the productivity of vegetation can be analysed through the capture and conversion of environmental resources. The most basic resources that a plant would obtain are from the atmosphere and soil. The plants obtain carbon dioxide, light, temperature, and humidity from the atmosphere, whereas obtains water and other mineral nutrients from the soil. So resource capture is classified as the above ground and below ground resource capture.

The crops depend on light for growth and depend on day length and temperature for its development. In the below ground resource capture, key natural resource which provides the most essential forms of nutrients for the plants growth which is associated with the integrated effect of management on most properties of soil that determines the sustainability and crop productivity is the ‘soil’. Good soil quality not only produces good crop yield, but also maintains environmental quality and consequently plant, animal and human health.. Growing of crops one after another without giving due consideration to nutrient requirement has resulted in decline in soil fertility, especially of nitrogen. Studies say that Zero- or reduced tillage crop production practices, coupled with proper residue management can maintain or improve soil organic matter and has the potential to substantially increase long-term crop production in semi-arid rain fed regions. [1]

Conclusion

Naylor,

[1] Long-term soil management effects on crop yields and

soil quality in a dryland Alfisol

K.L. Sharmaa,*, Uttam Kumar Mandala, K. Srinivasa, K.P.R. Vittala,

Biswapati Mandalb, J. Kusuma Gracea, V. Ramesha , Soil & Tillage Research 83 (2005) 246-259

[2] Advances in weed management strategies

C.M. Ghersaa,*, R.L. Benech-Arnoldb, E.H. Satorreb, M.A. MartõÂnez-Ghersaa, Field Crops Research 67 (2000) 95±104

[3] High-yield irrigated maize in the Western U.S. Corn Belt: II. Irrigation

management and crop water productivity

Patricio Grassinia, Haishun Yangb, Suat Irmakc, John Thorburnd, Charles Burre, Kenneth G. Cassmana,âˆ-, Field Crops Research 120 (2011) 133-141

[4] Some agrometeorological aspects of pest and disease

management for the 21st century

Joyce Fox Strand, Agricultural and Forest Meteorology 103 (2000) 73-82

[5] Targeting the farmer decision making process: A pathway to increased

adoption of integrated weed management

R.S. Wilson a,*, N. Hooker e, M. Tucker d, J. LeJeune c, D. Doohan b, Crop Protection 28 (2009) 756-764