Detailed notes-2- chapter-12 – class 9

MANURE

1. 1. Nutrient Supply and Soil Enrichment:

      • Manure contains organic matter and small quantities of nutrients essential for plant growth.
      • Enriches soil with nutrients and organic matter, enhancing soil fertility and promoting healthy plant growth.
      • Improves soil structure by increasing water holding capacity in sandy soils and promoting drainage in clayey soils, thus mitigating waterlogging.

   2. Environmental Benefits:

      • Utilizes biological waste materials, reducing reliance on chemical fertilizers and protecting the environment from potential pollution.
      • Promotes recycling of farm waste, contributing to sustainable agricultural practices and waste management.

Types of Manure:

1. 1. Compost and Vermicompost:

      • Composting involves the decomposition of farm waste materials like livestock excreta, vegetable waste, and straw in pits or compost bins.
      • Resulting compost is rich in organic matter and nutrients, providing a natural soil amendment for improving soil fertility.
      • Vermicomposting accelerates the decomposition process by using earthworms to break down organic materials, resulting in nutrient-rich vermicompost.

   2. Green Manure:

      • Green manure involves growing specific plants like sun hemp or guar and incorporating them into the soil before sowing crop seeds.
      • These green plants add organic matter to the soil as they decompose, enriching it with nitrogen and phosphorus.
      • Green manure crops also help suppress weeds, improve soil structure, and enhance soil fertility.

FERTILIZERS

1. Role of Fertilizers:

   • Commercially produced fertilizers supply essential nutrients like nitrogen (N), phosphorus (P), and potassium (K) to plants, promoting vegetative growth and overall plant health.
   • Proper use of fertilizers can contribute to higher yields in high-input farming systems by ensuring optimal nutrient availability to crops.

2. Application Considerations:

   • Fertilizers should be applied carefully, considering factors such as proper dosage, timing, and pre- and post-application precautions.
   • Excessive irrigation can lead to the leaching of fertilizers, causing pollution of water bodies and wastage of resources.
   • Over-reliance on fertilizers without replenishing organic matter in the soil can lead to soil degradation and loss of soil fertility over time.

3. Balancing Fertilizer Use with Organic Practices:

   • While fertilizers provide short-term benefits, the long-term sustainability of soil fertility should be considered.
   • Organic farming practices minimize or eliminate the use of chemical fertilizers, herbicides, and pesticides, emphasizing the use of organic manures, recycled farm waste, and bio-agents.
   • Organic farming systems promote soil health and biodiversity, enhancing the resilience of agricultural ecosystems and reducing environmental impacts.

4. Benefits of Organic Farming:

   • Organic farming systems focus on maximizing the input of organic matter into the soil, promoting soil structure, water retention, and nutrient cycling.
   • Practices such as mixed cropping, intercropping, and crop rotation help control pests and diseases naturally while maintaining soil fertility.
   • The use of biofertilizers, bio-pesticides, and beneficial microorganisms further supports plant health and productivity in organic farming systems.

12.1.2 (ii) IRRIGATION 

1. Wells:

   • Dug Wells: These wells collect water from shallow water-bearing strata.
   • Tube Wells: Tube wells tap into deeper water sources and are often equipped with pumps to lift water for irrigation.

2. Canals:

   • An extensive irrigation system where canals receive water from reservoirs or rivers.
   • Main canals branch into smaller distributaries, which further divide into field channels to irrigate agricultural lands.

3. River Lift Systems:

   • Used in areas where canal flow is insufficient or irregular.
   • Water is directly drawn from rivers and lifted for irrigation purposes, particularly in regions close to rivers.

4. Tanks:

   • Small storage reservoirs that collect runoff from smaller catchment areas.
   • Tanks intercept and store rainwater, providing supplemental irrigation during dry periods.

Additionally, new initiatives such as rainwater harvesting and watershed management have been implemented to increase water availability for agriculture:

• Rainwater Harvesting: Involves capturing and storing rainwater for agricultural use. Techniques include building small check dams to intercept runoff, increasing groundwater levels, and reducing soil erosion.

• Watershed Management: Focuses on conservation and sustainable use of natural resources within a watershed area. Activities may include afforestation, contour trenching, and construction of check dams to enhance water availability and soil moisture retention.

12.1.2 (iii) CROPPING PATTERNS

1. Mixed Cropping:

   • In mixed cropping, two or more crops are grown simultaneously on the same piece of land.
   • Examples include wheat + gram, wheat + mustard, or groundnut + sunflower.
   • Mixed cropping reduces risks and provides insurance against the failure of one crop, as different crops have different growth requirements and tolerances to environmental stressors.

2. Inter-cropping:

   • Inter-cropping involves growing two or more crops simultaneously on the same field in a specific pattern.
   • In this method, a few rows of one crop alternate with a few rows of another crop.
   • Example inter-cropping combinations include soybean + maize or finger millet (bajra) + cowpea (lobia).
   • Inter-cropping maximizes nutrient utilization, reduces pest and disease spread, and enhances overall crop productivity.

3. Crop Rotation:

   • Crop rotation involves growing different crops successively on the same piece of land in a pre-planned sequence.
   • The choice of crops for rotation depends on factors such as moisture availability, irrigation facilities, and nutrient requirements.
   • Proper crop rotation helps maintain soil fertility, control pests and diseases, and optimize yields.
   • Depending on the duration, crop rotation can be planned for different combinations of crops, allowing for multiple harvests in a year.

12.1.3 CROP PROTECTION MANAGEMENT

1. Weeds:

   • Weeds compete with cultivated crops for nutrients, water, and light, thereby reducing crop growth and yields.
   • Common weeds include Xanthium (gokhroo), Parthenium (gajar ghas), and Cyperinus rotundus (motha).
   • Weed control methods include mechanical removal, such as hand weeding or using tools like cultivators and weeders.
   • Preventive measures like proper seed bed preparation, timely sowing of crops, intercropping, and crop rotation can also help suppress weed growth.

2. Insect Pests:

   • Insect pests damage crops by cutting roots, stems, and leaves, sucking cell sap, or boring into stems and fruits.
   • Control methods include the use of pesticides, such as insecticides, which are sprayed on crops or applied to seeds and soil.
   • Other preventive measures include the use of resistant crop varieties and cultural practices like summer ploughing to disrupt pest life cycles.

3. Diseases:

   • Plant diseases caused by pathogens like bacteria, fungi, and viruses can spread through soil, water, and air, leading to crop damage and yield losses.
   • Disease control methods include the use of fungicides, which are sprayed on crops to prevent or treat fungal infections.
   • Preventive measures include selecting disease-resistant crop varieties and practicing good sanitation and crop management practices.

4. Challenges and Considerations:

   • While pesticides are effective in controlling weeds, pests, and diseases, their excessive use can lead to environmental pollution and harm non-target organisms.
   • Integrated Pest Management (IPM) approaches aim to minimize pesticide use by integrating multiple control methods, including biological control, cultural practices, and judicious pesticide application.