Dryland Agriculture

Dryland Agriculture refers to the cultivation of crops entirely under rainfed conditions. According to the ‘Principles of Agronomy’ by Reddy and Reddi, Dryland Agriculture is classified into three categories based on annual rainfall:

(a) Dry Farming:

• Practiced in areas where annual rainfall is less than 750 mm.
• Crop failures due to prolonged dry spells during the crop period are common.
• Practiced in arid regions with the help of moisture conservation practices.
• Alternate land use systems are suggested in these regions.

(b) Dryland Farming:

• Cultivation of crops in areas where annual rainfall is between 750 mm and 1150 mm.
• Dry spells may occur, but crop failures are less frequent.
• Higher Evapotranspiration (ET) than total precipitation causes moisture deficit.
• Soil and moisture conservation measures are essential in semi-arid regions.
• Drainage facilities may be required, especially in black soils.

(c) Rainfed Farming:

• Practiced in regions where annual rainfall exceeds 1150 mm.
• Low chances of crop failures due to adequate rainfall.
• Drainage becomes a significant issue.
• Practiced in humid regions.

Comparison Between Dryland and Rainfed Farming

Problems and Prospects of Dryland Agriculture

​India’s agricultural landscape is characterized by a significant reliance on rainfed and dryland farming systems. Recent data indicates that approximately 51% of the country’s net sown area is under rainfed agriculture, contributing nearly 40% to the total food production. ​

Dryland regions play a pivotal role in the cultivation of various crops:​

• Pulses: Approximately 95% of pulses are cultivated in dryland areas.​
• Oilseeds: These regions account for about 75% of oilseed production.​
• Coarse Grains: Notably, 80% of maize, 80% of jowar (sorghum), and 90% of bajra (pearl millet) are produced in dryland zones.​
• Cotton: Dryland farming contributes to 70% of the nation’s cotton production.

Challenges in Dryland Agriculture

• Rainfall Issues: Inadequacy and uncertainty of rainfall with erratic distribution. Late onset and early cessation of rains. Prolonged dry spells during the crop period.
• Soil Issues: Low moisture retention capacity. Poor soil fertility conditions.
• Socio-Economic Constraints: Predominance of small and marginal farmers (54% of holdings are <1 hectare). Limited infrastructure and access to timely credit and inputs.
• Technological Constraints: Lack of appropriate technologies for dryland agriculture.
• Developmental Constraints: Insufficient research and policy support.

Types of Agriculture in Dryland Areas:

1. Crop Production
2. Animal Husbandry with Pasture Management
3. Agroforestry

Drought and Agricultural Drought

• Drought (IMD Definition): Occurs when annual rainfall is less than 75% of normal.
• Severe Drought: Rainfall deficiency above 50% of normal.
• Agricultural Drought: Moisture deficit in the soil that fails to meet the crop’s evapotranspiration needs.
• Drought Areas: Areas where drought occurs in 20% of years.
• Chronic Drought Areas: Areas where drought occurs in more than 40% of years.

International Research Institutions on Dryland Agriculture

• ICRISAT: International Crop Research Institute for the Semi-Arid Tropics, established on October 11, 1972, near Hyderabad (Patancheru).
• ICARDA: International Centre for Agricultural Research in Dry Areas, established in 1977 in Aleppo, Syria.

Moisture Indices Used in Dryland Agriculture

i)                Moisture Availability Index (MAI)

• Measures the balance between rainfall and evapotranspiration.
• Formula: MAI =  Rainfall of 50% Probability / Potential Evapotranspiration

ii)              Aridity Index (A.I.)

• Measures the water deficit in an area.
• Formula: A.I.=Water Deficit (WD) / PET × 100

iii)             Moisture Deficit Index (MDI)

• Measures soil moisture deficit.
• Formula: MDI = Deficit Precipitation (DPT) / PET × 100 

iv)             Thornthwaite Moisture Index (TMI)

• Measures actual evaporation probability.
• Formula: TMI=Actual Evaporation (AE) / Potential Evaporation (PE)

Institute Related to Dryland Farming

International Institutes:

• ICRISAT (International Crops Research Institute for the Semi-Arid Tropics)
  • Established: 1972
  • Location: Patancheru, Hyderabad, India
  • Focus Areas: Research on crops suitable for semi-arid tropics, including sorghum, pearl millet, pigeon pea, chickpea, and groundnut.

• ICARDA (International Center for Agricultural Research in the Dry Areas)
  • Established: 1977
  • Location: Formerly in Aleppo, Syria (now headquartered in Morocco)
  • Focus Areas: Sustainable agricultural practices for dry areas, crop improvement, and water management.

National Institutes (India):

• AICRPDA (All India Coordinated Research Project for Dryland Agriculture)
  • Established: 1970
  • Headquarters: Central Research Institute for Dryland Agriculture (CRIDA), Hyderabad
  • Focus Areas: Dryland farming research, soil and water conservation, and climate-resilient agriculture.

• CRIDA (Central Research Institute for Dryland Agriculture)
  • Established: 1985
  • Location: Hyderabad, India
  • Affiliated With: Indian Council of Agricultural Research (ICAR)
  • Focus Areas: Enhancing productivity and sustainability in dryland regions, watershed management, and climate adaptation.

• ICAR – Indian Institute of Soil and Water Conservation (IISWC)
  • Established: 1954
  • Location: Dehradun, Uttarakhand
  • Focus Areas: Soil and water conservation in rainfed and dryland agriculture.

• ICAR – Central Arid Zone Research Institute (CAZRI)
  • Established: 1959
  • Location: Jodhpur, Rajasthan
  • Focus Areas: Agricultural research for hot arid regions, drought mitigation strategies, and desertification control.

• Mahatma Phule Krishi Vidyapeeth (MPKV)
  • Location: Rahuri, Maharashtra
  • Focus Areas: Research on dryland crops, soil and water management, and improved dryland farming technologies.

• University of Agricultural Sciences, Dharwad (UASD)
  • Location: Dharwad, Karnataka
  • Focus Areas: Research on dryland crops, sustainable rainfed agriculture, and water-use efficiency.

Jalshakti: A soil amendment that improves aeration, infiltration, and water-holding capacity of the soil.

Evapotranspiration (ET): The combined process of evaporation from soil and transpiration from plants, accounting for the major water loss in dryland agriculture. 60-75% of rainfall is lost this way. Strategies to reduce ET loss include mulches, antitranspirants, windbreaks, and weed control.

Antitranspirants: Materials that reduce water loss from plants, classified into:

• Stomata Closing Type: Reduces water loss by closing stomata (e.g., PMA, Atrazine).
• Film Forming Type: Forms a thin film to reduce moisture loss (e.g., Mobileaf, hexadecanol).
• Reflecting Type: Reflects radiation, reducing leaf temperature and transpiration (e.g., Kaolin).
• Growth Retardants: Reduce shoot growth, increase root growth, and help plants resist drought (e.g., Cycocel).

Windbreaks and Shelterbelts: Structures that reduce wind speed, prevent wind erosion, and protect crops from desiccating winds. They can reduce wind speed by 60-80% on the leeward side. Shelterbelts also provide habitats for wildlife and produce useful resources like fuelwood and cattle feed. The effectiveness of shelterbelts depends on the wind speed, direction, and planting pattern (tall trees on the inner side and shrubs/grasses on the outer side).