Contingent Crop Planning for Aberrant Weather

Effect of Aberrant Weather Conditions on Crops Aberrant weather conditions, particularly in dry farming areas, can significantly impact crop yields. These conditions often arise due to deviations in rainfall behavior such as:

• Delayed Onset of Rainfall: The cropping season is shortened, resulting in delayed sowing.
• Early Withdrawal of Rainfall: This causes moisture stress at maturity, leading to reduced grain filling.
• Intermediate Dry Spells: These dry spells occur during various crop growth stages, affecting germination, vegetative growth, flowering, ripening, and grain filling.

Each of these conditions requires targeted management practices to mitigate their adverse effects. These practices, collectively known as contingency planning, help minimize losses by adjusting crop management strategies after crop establishment or during mid-term growth.

Rainfall Aberrations and Their Effect on Crops:

1. Delay in Onset of Rainfall:
   • Effect: Shortened cropping season, delayed sowing.
   • Mitigation: Select crops with shorter growth periods that can still mature within the available time.
2. Early Withdrawal of Rainfall:
   • Effect: Moisture stress during critical stages, especially grain filling.
   • Mitigation: Employ irrigation strategies if possible, or grow drought-resistant crops.
3. Intermediate Dry Spells:
   • Effect: Varies depending on the crop stage.
     • Post-sowing: Affects germination and reduces plant population.
     • Vegetative Stage: Reduces stem elongation, leaf expansion, and branching.
     • Flowering: Reduces pollination and grain or pod numbers.
     • Ripening: Reduces grain filling and size.
   • Mitigation: Utilize soil moisture conservation methods, irrigation if feasible, and use drought-tolerant varieties.

Contingency Cropping: Contingency cropping involves changing the crop selection to adapt to aberrant weather conditions. This ensures that a farmer is still able to make a profit by planting a suitable crop that matches the rainfall patterns, despite uncertainties in weather conditions.

• In dryland agriculture, contingency cropping may become necessary when the monsoon onset is delayed. Depending on when rainfall occurs, farmers may need to switch crops to adapt to the altered weather pattern.
• In regions with highly variable rainfall, contingency cropping is especially essential, as rainfall may vary across fields even in the same locality.
• Location-Specific: Because rainfall distribution can be highly localized, contingency cropping must consider the local agricultural environment.

Types of Contingent Crop Plans:

There are six types of contingent crop plans to manage different types of weather aberrations. These plans aim to mitigate the impact of erratic weather on crop yield.

Contingent Crop Plan for Inadequate and Uneven Distribution of Rainfall When rainfall is both low and unevenly distributed, the crop yield becomes highly uncertain. The rainfall can occur either in excess or deficiency at critical stages, making it essential to manage the water supply for the crops effectively.

Management Strategies:

• Short Duration Crops: These crops mature quickly, minimizing the risks of crop failure.
• Low Water-Required Crops: Choose crops that require less water and can thrive in moisture-scarce conditions.
• Life-Saving Irrigation: In areas where irrigation is possible, applying life-saving irrigation can help crops through critical stages of growth.

Contingent Crop Plan for Long Gaps in Rainfall When long dry spells occur during the monsoon, there is a risk of crop failure due to inadequate water for plant growth. In such cases, certain strategies can be employed to reduce the negative impact.

Management Strategies:

• Increase Seed Rate: To ensure an adequate plant population, increase the seed rate.
• Spray Urea Solution: Foliar application of urea can enhance crop growth during dry spells.
• Life-Saving Irrigation: Provide irrigation during critical growth stages.
• Weeding and Intercultural Operations: Reduce competition for moisture and nutrients by maintaining proper field sanitation.

Contingent Crop Plan for Early Onset of Monsoon In areas where the monsoon starts early, farmers can take advantage of the early rains to sow crops that benefit from such conditions.

Management Strategies:

• Cultivate Early-Maturing Crops: Grow crops such as pearl millet and sesame, which can be harvested before the season ends.
• Short Duration Crops: Crops that mature quickly are ideal for early onset conditions.
• Moisture Conservation: Implement practices like mulching to conserve soil moisture.
• Cultural Methods: Adopt appropriate cultural practices such as proper plant spacing and crop rotation to manage excess moisture.

Contingent Crop Plan for Late Onset of Monsoon: When the monsoon is delayed, sowing is postponed, and crop growth suffers due to shortened growing periods.

Management Strategies:

• Alternate Crops and Varieties: Use drought-resistant crops such as castor (Aruna), green gram, cowpea, and sunflower.
• Dry Sowing: This involves sowing crops without waiting for rain, taking advantage of residual soil moisture.
• Seed Soaking and Treatment: Pre-sow seed treatments can help crops germinate better when the rains arrive.
• Transplanting: Transplant one-month-old seedlings, such as Bajra, to save time and ensure better growth.
• Weed Control: Complete weed control is essential to reduce competition for limited water.

Contingent Crop Plan for Early Cessation of Rains In some cases, the monsoon season may end abruptly, leading to drought stress during flowering and maturity, severely affecting yields.

Management Strategies:

• Short Duration Varieties: Grow fast-maturing varieties that can be harvested before the rains stop.
• Mulching: Use organic or inorganic mulches to reduce moisture loss.
• Life-Saving Irrigation: Apply irrigation if available during critical flowering and maturation stages.
• Decrease in Plant Population: Reduce plant density to conserve water for remaining plants.

Contingent Crop Plan for Prolonged Dry Spells Prolonged dry spells during the monsoon can drastically reduce crop yields or cause crop failure. Special strategies must be employed during these periods.

Management Strategies:

• Mild Moisture Stress: In cases of mild stress (30-35 days after sowing), thinning alternate rows of sorghum and pearl millet can reduce competition for moisture.
• Severe Moisture Stress: If the dry spell is severe, cut the sorghum or pearl millet and ration the remaining crop to conserve resources.
• Blooming Stage Stress: If dry spells occur during flowering, cut and ration crops to manage moisture.
• Shallow Inter-Cultivation: Break the monsoon for a short while and perform shallow inter-cultivation to eradicate weeds and create soil mulch for moisture conservation.
• Wider Spacing: Use wider row spacing to conserve moisture.
• Urea Spray: Spray 2% urea after drought periods to stimulate growth in indeterminate crops such as castor, pigeon pea, and groundnut.

Contingent Crop Plan for Dry Spells During Crop Growing Period When dry spells occur after crop sowing, particularly during critical growth stages, adjustments are needed to sustain crop growth.

Management Strategies:

• Ratooning: For crops like sorghum and pearl millet, allow ratooning to promote regrowth after the dry spell.
• Mulching: Use mulch to conserve soil moisture during dry periods.
• Thinning: Thinning plants can help reduce competition for the limited moisture.