Crop Production Improvement | Science Class 9 PDF Download

Food Crops - Crop Variety Improvement

The food we eat keeps us strong and healthy. Food provides us with the nutrients and energy that we need for the proper functioning and growth of the body. As human beings are incapable of synthesizing food, we depend on plants and animals for our food. The population explosion has led to a greater demand for basic requirements such as food, shelter, clothing, etc. Another impact of population on food crop production is land exploitation. Thus, cultivation has been limited to a small area.
In order to meet the demands with limited resources, we need to apply a greater effort. Crop variety improvement, crop production improvement and crop protection management are three major ways to improve food crops production.

Food Crops

Food crops are crops that contribute to the world’s major food supply. They comprise grains, seeds, nuts, vegetables, fruits, legumes, spices, herbs, beverages, etc.
Grains are a major source of human food. They serve as a staple food for the majority of population. These include rice, wheat, maize, barley, etc.
Legumes and dried beans have a longer shelf-life and are economical. Thus, they can be used in seasons when food is scarce.
Seeds and nuts are the powerhouses of energy and a concentrated form of food.
Herbs have a strong flavour. These mainly comprise leaves, stems, flowers, roots and seeds.

Methods of Crop Variety Improvement

Crop variety improvement is the primary step to improve food crop production. It helps in the development of crops with desired traits such as high yields, disease resistance, quality product and response to fertilizers. We can raise different strains of food crops with desirable traits naturally as well as scientifically. Two of them are as follows:

Hybridization

The crossing of genetically dissimilar plants is referred to as hybridization. Hybridization may take place between different varieties (intervarietal), between two different species of the same genus(interspecific) or between different genera (intergeneric).

Gene Incorporation

Genes are responsible for the traits. Thus, we can improve crop quality and quantity by incorporating the genes with desirable traits. This method is more scientific and results in genetically modified food crops.

Crop production is more like a business in many countries. Thus, the strains we develop must be economically profitable. The new varieties should be able to produce maximum quality and quantity under different conditions and regions. Hence, we need to be very selective about seeds for its acceptance.

Why is Crop Variety Improvement Important?

We know resources are very limited, but the demand is very high. Thus, the basic reason for variety improvement is to meet the requirements. However, the quality and quantity of the crop produced shouldn’t be compromised due to the limited resource and present scenario. This is why scientist developed different varieties. The different strains should be able to show maximum productivity under any diverse condition. This leads to the idea of improvement of food crops variety.

The variety improvement is done for the following reasons.

• Higher yield: Crop variety improvement’s main goal is to increase the productivity of the crop. To develop high yielding variety.
• Quality product: To improve the quality of the food crops. The quality of the crop depends on the type of crop. Considering the pulses and grains, they must have better baking quality. Oil crops should give quality oil.
• Resistance: To develop resistance to both living and non-living factors. Biotic factors like insects, parasites, diseases, etc. and abiotic factors like hot, cold, drought, salinity, etc. affect crop production. Resistant variety can withstand these factors and give a high yield.
• Maturity period: To shorten and to develop uniform maturity period. The short maturity period of crops helps farmers in multiple rounds of cultivation in less expenditure during a short period. Also, the uniform maturity of crops helps in easy harvesting. Thus, the overall variety of improvement makes the situation more profitable.
• Adaptation: To develop tolerance and make crops more adaptable to different conditions. The crops can be grown even in diverse conditions. For example, crops with tolerance to high salinity soil.
• Desirable agronomic characteristics: To develop desired agronomic characters in crops. This helps in a higher yield in less expenditure. For example, dwarfness in cereals reduces the nutrient consumption without affecting the yield.

What are Nutrients?

Plants require some nutrients in large quantities called macronutrients while some in smaller quantities known as micronutrients. Gases such as carbon dioxide and oxygen are provided through the air while hydrogen is provided by water. Soil supplies thirteen additional micronutrients(Iron, copper, zinc, chlorine, boron, manganese) and macronutrients (calcium, magnesium, potassium, nitrogen, phosphorous).
Deficiency of these nutrients inhibits the growth of plants, affects their life cycle, processes and decreases their immunity against diseases. Soil’s fertility can be increased by providing nutrients in the form of manure and fertilizers.

What is Nutrient Management?

Nutrient management refers to the efficient use of crops to improve productivity. It is necessary to balance the soil nutrient input with the crop requirement. If the nutrients are applied at the right time and in adequate quantities, optimum crop yield is obtained. If applied in huge amounts, it will harm the crop, and if applied in small quantities it limits the yield. The nutrients that are not utilized by the crops leach into groundwater or nearby surface water.

Integrated Nutrient Management

Integrated nutrient management is the combined application of chemical fertilizers and organic manures for crop production. Its main aim is the maintenance of soil fertility and the supply of plant nutrients in adequate amounts. It is ecologically, socially and economically viable.

Concepts of Integrated Nutrient Management

• The nutrients stored in the soil.
• The nutrients purchased from outside the farm.
• Plant nutrients present in crop residues, manures, and domestic wastes.
• Nutrient uptake by crops at harvest time.
• Plant nutrients lost from the field during crop harvest or through volatilization.

Manures and Fertilizers in Nutrient Management

Manures

• Contains small quantities of nutrients and large quantities of organic matter
• Formed as a result of decomposition of plant wastes and animal excreta
• Enriches soil with nutrients and organic matter thereby increasing its fertility
• Bulk organic matter improves soil structure, which increases water-retaining capacity in sandy soil, helps in drainage and water clogging in clayey soil.
• Manure contains biological wastes obtained as a result of recycling and is preferred over the use of fertilizers.

Manure can be classified into two types based on the kind of biological material used: Compost and vermicompost
Composting is carried out using farm wastes. Vermicompost is prepared using earthworms.
Green manure: Some green plants are mulched into the soil while sowing seeds, which helps enrich the soil with nitrogen and phosphorous.

Fertilizers

• These commercially produced plant nutrients provide macronutrients to ensure good vegetative growth. They yield more crops and results in high-cost farming
• Use of fertilizers needs to be monitored properly as excessive fertilizer gets washed away without being absorbed by the soil, resulting in water getting polluted.
• Continuous use of fertilizers causes harm to microorganisms that live in the soil. These are beneficial in carrying out agricultural processes.
• To yield optimum crop production we have to minimize the use of fertilizers and maximize the use of manure.

Importance of Nutrient Management

Nutrient management is important for the following facts:

• Nutrient management helps to reduce contamination to waterways by plant nutrients.
• Improve soil fertility.
• Enhance plant productivity.
• Reduce the cost of chemical fertilizers.
• Providing balanced nutrition to crops.
• Promotes carbon sequestration and prevents the deterioration of soil, water, ecology, and also leaching of nutrients from the soil.

Irrigation

Irrigation is the artificial process of applying water to the crops to fulfil their water requirements. There are different types of irrigation practised for improving crop yield. This process helps in ensuring that the crops get water at the right stages .i.e. during their growing season, which helps in increasing the expected yields of crop. Irrigation is done with the help of Canals, Wells, River lift system, Tanks, Rainwater harvesting and watersheds.