Chapter 1 Crop Production and Management Class 8 – Simplified notes

Agricultural Practices-   Importance and Methods of Cultivation

Importance of Cultivation 

Cultivation plays a crucial role in our lives as it is the fundamental way to produce food, essential for survival. It involves growing crops systematically to meet the dietary needs of people. Good cultivation practices ensure a steady supply of food which is vital given the growing population.

Different Methods of Cultivation 

Cultivation involves various activities that prepare the land for growing crops effectively. Here are the key steps involved:

1. Preparation of Soil: Before sowing seeds it is essential to prepare the soil. This involves tilling or ploughing, which helps in turning the soil and making it loose. Loosening the soil allows plant roots to penetrate deeply and spread out easily, which is vital for strong growth.
2. Sowing: After soil preparation, the next step is sowing. High-quality seeds are chosen and spread across the field using tools like seed drills. This ensures that seeds are planted at the right depth and spacing, which is crucial for the optimal growth of the plants.
3. Watering (Irrigation): Crops need water to grow and providing water at the right time is known as irrigation. Various methods like traditional watering cans or advanced drip and sprinkler systems are used depending on the size of the fields and the type of crops.
4. Adding Manure and Fertilisers: To enrich the soil with nutrients, manure (organic) or fertilisers (inorganic) are added. Manure improves the soil’s texture and fertility sustainably, while fertilisers are used for a quicker nutrient supply to ensure robust crop growth.
5. Weeding: Removing unwanted plants, or weeds, is crucial as they compete with the crops for nutrients and sunlight. Weeding ensures that the crops have all the resources they need to grow healthily.
6. Protection from Pests: Using natural or chemical methods to protect crops from pests and diseases is essential to ensure that the plants grow to their full potential and produce a good yield.
7. Harvesting: Once the crops are mature, they are harvested. Harvesting must be done at the right time to ensure that the maximum amount of produce is recovered before the crops start to decay.
8. Storage: After harvesting, the produce needs to be stored properly to prevent spoilage. Proper storage techniques ensure that the food remains usable for a longer period.

Crop Types in India

Crop Classification

India’s diverse climate allows for the cultivation of various types of crops throughout the year. These crops are broadly classified into two categories based on the season they are grown in: Kharif and Rabi. This classification is crucial for agricultural planning and ensuring food security for the nation.

1. Kharif Crops

• Growing Season: Kharif crops are synonymous with the Indian monsoon. They are sown at the beginning of the monsoon season around June and are harvested by the end of the monsoon season in September or October.
• Climate Requirements: These crops thrive in warm wet weather and require substantial water for growth, which is typically provided by the monsoon rains.
• Examples:
  • Paddy (Rice): It is the most significant Kharif crop in India, requiring lots of standing water and thus grown extensively in areas with high rainfall or irrigation facilities.
  • Maize: Cultivated for both human consumption and as fodder, maize demands moderate rainfall and temperature to flourish.
  • Soybean: Used for oil and protein, soybean grows best under warm and moist conditions.
  • Groundnut: A major oilseed crop, it requires a long warm growing season.
  • Cotton: Needs a lot of moisture initially and then dry weather closer to harvest.
• Importance: These crops are vital for the agrarian economy as they coincide with the major rainy season in India, ensuring water availability.

2. Rabi Crops:

• Growing Season: Rabi crops are planted at the onset of the cool season, post-monsoon, around mid-November and are harvested in spring, from April to June.
• Climate Requirements: These crops do well in cold conditions and require relatively less water, which is often provided by the winter rainfall in the northern parts of India.
• Examples:
  • Wheat: The primary staple for a large part of the Indian population, wheat requires a cool growing period and a warmer period for maturation.
  • Gram (Chickpea): This legume is a significant source of protein in the Indian diet and thrives in mild winter climates.
  • Pea: Grows well in cooler climates and is both used as a food crop and for fodder.
  • Mustard: Known for its oil seeds, mustard requires a cold climate to start its growth with a subsequent warm period to support flowering and seed production.
  • Linseed: Used for its oil and as a nutritional supplement, it grows best in temperate climates.
• Importance: Rabi crops are crucial for balancing India’s agricultural output throughout the year, providing staple foods and important commercial crops during the dry season.

Implications of Seasonal Crop Planning:

• Soil Health: Rotating between Kharif and Rabi crops helps in maintaining soil fertility by alternating the types of nutrients absorbed from the soil, thereby preventing soil depletion.
• Water Management: Strategic planting according to the season helps in utilising natural rainfall efficiently, reducing the need for artificial irrigation and conserving water.
• Agricultural Productivity: Understanding and adapting to the seasonal growth patterns of these crops can lead to optimised yields and higher productivity per hectare.

Basic Practices of Crop Production

1. Preparation of Soil: Soil preparation is the first and most critical step in crop production. This process, often called tilling or ploughing, involves turning the soil upside down and breaking it down. The main goals are:

• To make the soil loose: This helps plant roots penetrate deep into the soil, improving their access to water and nutrients.
• To bring nutrient-rich soil to the surface: This gives plants better access to essential nutrients.
• To aerate the soil: Loosening the soil lets air circulate through it, which is crucial for healthy root growth.
• To remove weeds: Ploughing helps get rid of old weeds and prevents weed seeds from growing.

2. Sowing: Sowing is placing seeds in the soil to grow crops. Proper sowing ensures good germination and eventual crop yield. Here are the critical aspects:

• Use of seed drills: Modern agriculture often uses seed drills, which ensure seeds are sown at uniform distances and depths. This uniformity is essential for the optimal growth of crops.
• Choosing the right seeds: Only high-quality, disease-free seeds are chosen for sowing to increase the chances of healthy plant growth.

3. Adding Manure and Fertilisers: To ensure that the soil remains fertile and capable of supporting crop growth, farmers add manure and fertilisers.

• Manure: This is organic matter derived from decomposed plants or animal excrement. It improves soil texture, adds nutrients and enhances water retention.
• Fertilisers: These are chemical substances supplied to the crops to increase their productivity. They are rich in specific nutrients like nitrogen, phosphorus and potassium, which are essential for plant growth.

4. Irrigation: Irrigation is the artificial application of water to soil or land to assist in the growing of agricultural crops. Since water is crucial for plant growth, effective irrigation is necessary.

• Traditional methods: These include using human or animal power to draw water from wells, lakes, or rivers.
• Modern methods: Such as sprinkler systems, which spray water over the crops like rain and drip systems, where water drips slowly to the roots of plants, minimising wastage.

5. Protecting from Weeds: Weeds compete with crops for nutrients, light and space and must be controlled through weeding.

• Manual removal: Using tools like khurpi to physically remove weeds.
• Use of weedicides: Chemicals that kill weeds without harming the crops. These need to be used carefully to avoid affecting both the environment and human health.

6. Harvesting: Harvesting is the process of collecting the mature crop from the field.

• Manual harvesting: Using tools like sickles to cut the crop.
• Mechanical harvesting: Using machines like harvesters, which can cut and collect the crop efficiently.

7. Storage: Proper storage is essential to prevent spoilage and protect the quality of harvested grains.

• Drying: Grains must be dried to reduce moisture, which helps prevent the growth of mold and bacteria.
• Methods of storage: Using silos, granaries, or metal bins to protect the grains from pests and extreme weather.

Importance of Turning and Loosening the Soil

Soil Preparation

 Preparing the soil by turning and loosening is a fundamental step before planting any crop. This process is often done using tools like ploughs and involves mixing the soil layers and breaking down clumps.

Why Turn and Loosen the Soil?

1. Allows Roots to Grow Deeply:
   • When the soil is loose, plant roots can grow deeper into the ground.
   • Deep roots help plants access water and nutrients from below the surface, which is vital during dry conditions.
2. Improves Soil Aeration:
   • Turning the soil helps mix air (oxygen) into it.
   • Oxygen is crucial for roots and beneficial soil organisms like earthworms and microbes that help break down organic matter into nutrients.
3. Enhances Water Absorption:
   • Loose soil absorbs rainwater and irrigation water better than compacted soil.
   • This prevents water runoff and ensures that water reaches the plant roots where it’s needed most.
4. Increases Fertility:
   • Turning the soil brings nutrient-rich layers from below to the surface.
   • It also helps mix organic matter like fallen leaves and manure evenly throughout the soil, which decomposes and adds more nutrients.
5. Controls Weeds:
   • Ploughing can bury weed seeds deep in the soil, preventing them from sprouting.
   • It also uproots existing weeds, making it easier to remove them and reducing competition for resources with the crops.

How Is Soil Turned and Loosened?

• Ploughing: This traditional method involves using a plough, which can be wooden or iron, pulled by animals or tractors. It digs into the soil, lifts it and turns it over.
• Harrowing: After ploughing, the soil often has large clumps. A harrow breaks these into smaller pieces to make the soil finer and ready for planting.
• Using Cultivators: These are tools or machines that further refine the soil texture and are particularly useful for removing weeds between rows of plants.

Irrigation- Sources and Methods

Irrigation

Irrigation is the process of supplying water to crops to help them grow when natural rainfall is not sufficient. This practice is essential for maintaining a steady supply of water to crops, ensuring healthy plant growth and successful harvests.

Different Sources of Water for Irrigation

Water for irrigation comes from several sources, each important depending on the region’s geography and climate:

1. Wells: Farmers dig wells to access groundwater. This water is usually pumped out using electric or diesel pumps.
2. Tubewells: Similar to wells but deeper, tubewells can tap into water sources deeper beneath the earth’s surface.
3. Ponds and Lakes: Surface water from ponds and lakes can be used directly or diverted through channels to the fields.
4. Rivers: Many farms are located near rivers, allowing farmers to divert water through canals or pipes directly to their fields.
5. Dams: Large dams store rainwater and river water, which is released into canals leading to agricultural fields.
6. Rainwater Harvesting: Collecting rainwater in large tanks or reservoirs to use during drier periods is an increasingly popular method.

Methods to Distribute Water Across Fields

 Farmers use various methods to distribute water across their fields, depending on the available technology, water source and crop needs.

Flood Irrigation:

• The oldest and simplest form, where farmers allow water to flow freely over the land.
• This method can lead to water wastage and uneven distribution, which is why it’s less favoured in water-scarce areas.

Furrow Irrigation:

• Involves digging trenches (furrows) along the field’s length and filling them with water.
• This allows water to seep into the ground and reach plant roots without covering the entire field’s surface.

Drip Irrigation:

• Water drips slowly directly to the base of each plant through a network of tubing and valves.
• This method is water-efficient, reduces evaporation and is ideal for areas with limited water supplies.

Sprinkler Irrigation:

• Mimics natural rainfall by spraying water through rotating sprinkler heads.
• Suitable for uneven terrain and helps in the even distribution of water over the field.

Subsurface Irrigation:

• Involves laying pipes beneath the soil surface that slowly release water to the roots.
• This method conserves water and is beneficial for crops sensitive to leaf moisture.

Manure and Fertilisers – Differences and Benefits

Introduction to Soil Nutrients: Crops require various nutrients for growth, which they absorb from the soil. Over time, soil can become depleted of these nutrients, making it necessary to replenish them. This can be done using manure and fertilisers, which are added to the soil to provide the necessary nutrients for plant growth.

1. Manure (Organic Option):

• Source: Manure is made from natural substances such as decomposed plants and animal excreta.
• Composition: It contains essential nutrients like nitrogen, phosphorus and potassium, but in lower quantities compared to fertilisers. It also contains humus, which improves soil structure.
• Benefits:
  • Enhances Soil Texture: Manure adds organic matter to the soil, making it more porous and improving its ability to retain water and nutrients.
  • Increases Microbial Activity: The organic matter in manure supports the growth of soil microbes, which play a critical role in nutrient cycling and help maintain soil health.
  • Environmentally Friendly: Manure is considered sustainable and reduces the risk of chemical runoff and pollution.
  • Long-term Soil Fertility: Regular application of manure maintains and slowly improves soil fertility over time.

2. Fertilisers (Inorganic Option):

• Source: Fertilisers are chemically synthesised or mined from mineral deposits.
• Composition: They are high in specific nutrients, which can be tailored to meet the needs of particular crops. Common formulations include NPK (Nitrogen, Phosphorus, Potassium).
• Benefits:
  • Immediate Nutrient Availability: Fertilisers are readily available to plants, providing a quick boost to growth, which is particularly useful during the critical stages of crop development.
  • Highly Efficient: Fertilisers can be applied in precise amounts to match the exact nutrient requirements of crops, reducing waste.
  • Boosts Crop Yield: The targeted application of fertilisers can significantly increase crop production and profitability.

Differences between Manure and Fertilisers:

• Nutrient Content: Manure has a lower concentration of nutrients compared to fertilisers, which are concentrated and can provide a specific balance of nutrients.
• Release of Nutrients: Manure releases nutrients slowly, which means it feeds plants over a longer period, whereas fertilisers provide a quick release of nutrients.
• Impact on Soil Health: Manure improves soil structure, increases water retention and enhances microbial life in the soil. Fertilisers, if used excessively, can lead to soil acidification, decrease organic matter in the soil and disrupt microbial ecosystems.
• Cost: Manure is generally less expensive and can be produced on-site from agricultural waste products. Fertilisers, however, are more costly, especially the synthetic types.

Weeding 

Weeding is the process of removing unwanted plants, known as weeds, from agricultural fields. These weeds compete with crops for essential resources like nutrients, water, space and light, impacting the growth and health of the crops.

Why is Weeding Important?

1. Resource Competition: Weeds are aggressive competitors. They can quickly take up nutrients and water that would otherwise be available to the crops. This competition can severely affect crop yield and quality.
2. Light Absorption: Weeds often grow taller and faster than the crops, shading the crop plants from necessary sunlight which is crucial for photosynthesis.
3. Space Utilisation: Weeds spread rapidly and can overcrowd crop plants, limiting their space and stunting their growth. This is particularly problematic in densely planted fields where space is already limited.
4. Disease and Pest Hosts: Weeds can host pests and diseases that can transfer to and infect crop plants. Removing weeds helps minimise this risk and can lead to healthier crops.
5. Water Usage: Weeds use up water that would otherwise be available to the crops. During periods of water scarcity, this competition can stress the crops and reduce their ability to survive and produce.

Methods of Weeding:

1. Manual Weeding: This involves physically pulling out the weeds from the ground using hands or tools like hoes and weed pullers. It is labour-intensive but effective in smaller areas.
2. Mechanical Weeding: This method uses machinery to remove weeds. It can be done using tillers, which uproot weeds, or larger machines that cut down weeds between crop rows. This is suitable for larger fields.
3. Chemical Weeding: The use of herbicides (weed killers) can efficiently control weeds over large areas. These chemicals are designed to target specific types of weeds without harming the crops. However, careful application is essential to prevent damage to the crops and the environment.
4. Mulching: Applying a layer of material (like straw, plastic, or other organic compost) on the soil surface can help suppress weed growth by blocking sunlight. Mulching also helps retain soil moisture and adds nutrients to the soil as organic mulches decompose.

Best Practices in Weeding:

• Regular Monitoring: Regularly checking fields for new weed growth is crucial. Early detection makes removal easier and lessens the competition for resources.
• Integrated Weed Management: Combining different weeding methods can be more effective. For example, mechanical weeding can be followed by mulching to prevent new weeds from growing.
• Timely Weeding: Weeding is most effective before weeds have matured and produced seeds. Removing weeds early in the season prevents them from spreading throughout the field.

Harvesting and Threshing – Methods and Tools

Harvesting is the process of collecting mature crops from the fields and threshing is the subsequent step of separating the edible parts (like grains) from the non-edible parts (like chaff and stalks).

1. Harvesting: 

Harvesting is a crucial stage in agriculture as it determines the actual yield of crops. Here are the methods and tools commonly used:

Manual Harvesting:

• Tools Used: The sickle is the most traditional tool used for manual harvesting. It is a hand-held cutting tool with a curved blade, effective for cutting the crop close to the ground.
• Process: Farmers manually cut the crop stalks, gather them and then tie them into bundles. This method is labour-intensive but allows for selective harvesting, which is essential for crops that do not ripen uniformly.

Mechanical Harvesting:

• Tools Used: Mechanical harvesters and combine harvesters are widely used in large-scale farming. A combine harvester can simultaneously harvest, thresh and winnow the crops.
• Process: The machine moves through the field, cutting the crop and processing it to separate the grains from the chaff. This method is much faster and efficient, suitable for extensive agricultural fields.

2. Threshing: 

Threshing involves separating grains or seeds from the stalks and husks.

Manual Threshing:

• Methods: Traditional methods include beating the harvested stalks against hard surfaces or using a flail (a manual threshing tool) to beat the grain bundles.
• Efficiency: This method is more common in regions with small farms or where access to machinery is limited.

Mechanical Threshing:

• Tools Used: Mechanical threshers and the threshing component of combine harvesters.
• Process: The machine forcefully beats or shakes the crops to dislodge the grains from the stalks. The grains are then collected within the machine or passed through a series of sieves and blowers that separate them from smaller debris.

Storage: Techniques to Keep Harvested Grains Safe and Prevent Spoilage

After harvesting, the proper storage of grains is crucial to maintain their quality and prevent spoilage. Effective storage helps protect grains from insects, rodents, fungi and other environmental factors that can degrade them.

Techniques for Effective Grain Storage:

1. Drying:
   • Purpose: Reducing moisture in the grains is vital because high moisture levels can lead to the growth of mold and fungi.
   • Method: Grains are spread out under the sun on tarps or drying floors until the desired moisture content is achieved. This usually takes a few days, depending on the weather conditions.
2. Cleaning:
   • Purpose: Removing impurities such as dirt, stones and broken seeds ensures that only healthy and intact grains are stored.
   • Method: Grains are sieved and sometimes washed to remove any debris before drying.
3. Use of Storage Facilities:
   • Silos: Large-scale storage structures that provide airtight conditions. Silos are particularly effective for storing vast amounts of grain safely for extended periods.
   • Granaries: Traditional storage rooms or buildings designed to protect grains from pests and the environment.
   • Metal Bins and Jute Bags: Common for smaller scale storage, these are used by farmers who do not have access to silos or granaries. Grains in these containers must be regularly checked and treated for pests.
4. Pest Control:
   • Chemical Treatments: Applying insecticides and pesticides can protect the grains from pests. However, this must be done carefully to avoid contaminating the grain.
   • Natural Methods: Using neem leaves or turmeric powder can act as natural deterrents against pests without the health risks associated with chemical treatments.
5. Controlled Environment:
   • Temperature and Humidity Control: Keeping storage areas cool and dry helps preserve grain quality and prevents the growth of pests and mold. This is especially important in humid climates.
6. Regular Inspection:
   • Purpose: Early detection of any issues such as pest infestations or mold growth can prevent the spread and reduce losses.
   • Method: Periodically checking the condition of stored grains and the storage environment ensures that any problems are addressed promptly.

Agricultural Implements – Essential Tools in Agriculture

Agricultural implements are crucial tools that assist in various stages of crop production. They make the process of farming more efficient and less labour-intensive. Here are some of the primary tools used and their specific functions:

1. Plough:

• Purpose: A plough is used for tilling the soil, turning it over and breaking it down. This is crucial for aerating the soil and preparing it for sowing seeds.
• Description: Traditionally made from wood and drawn by animals like bulls or horses, modern ploughs are often made of iron and can be attached to tractors.
• Function: The plough digs into the soil with a triangular iron blade (ploughshare) and a long log of wood (ploughshaft), making furrows for planting seeds. It also helps in burying weed remnants and crop residues, which decompose to add nutrients to the soil.

2. Hoe:

• Purpose: A hoe is primarily used for removing weeds and for loosening the soil surface around the crops.
• Description: It consists of a long handle with a strong, broad and bent metal blade.
• Function: The hoe is manually operated to cut weeds and aerate the top layer of the soil, which promotes better moisture and nutrient retention. It is also useful for creating narrow furrows (small ditches) for planting seeds and bulbs.

3. Cultivator:

• Purpose: Cultivators are used to stir and pulverise the soil, either before planting to aerate the soil or after the crop begins to grow to kill weeds.
• Description: Modern cultivators are tractor-driven and are more efficient than manual tools. They have multiple metal teeth or tines that break up compacted soil.
• Function: By breaking up the soil, cultivators help improve soil aeration and water absorption. They are also used to mix compost or fertiliser into the soil, enhancing soil fertility and promoting healthy crop growth.

Usage and Importance:

• Efficiency: These tools significantly reduce the human labour required to prepare the soil for planting, manage weeds and maintain crop health.
• Productivity: By improving soil conditions and reducing the weed population, these tools help in increasing crop productivity and yield.
• Sustainability: Proper use of these tools can help in maintaining the soil structure and fertility, promoting sustainable agricultural practices.