(a) List out the cereal- and millet-based cropping systems practised in India based on soil type and irrigation availability. (20…

(a) Cereal- and Millet-Based Cropping Systems by Soil Type and Irrigation

Cropping systems in India are broadly classified based on soil type and irrigation status. In irrigated alluvial soils of the Indo-Gangetic plains, the dominant system is the rice-wheat rotation, often supplemented with pulses or oilseeds in the summer (zaid) season. In areas with assured irrigation or high rainfall and high water tables (coastal deltas of peninsular and eastern India), rice-rice double cropping is practiced, though it depletes soil nutrients. Maize-wheat systems are common in the alluvial and medium-textured soils of northern and central India, particularly where irrigation is available for the rabi maize or wheat component.

In rainfed or semi-arid regions, millet-based systems prevail due to their drought tolerance. Pearl millet-mustard is a standard rotation in the light-textured sandy loam soils of Rajasthan and Haryana, where pearl millet (bajra) utilizes the monsoon moisture and mustard utilizes residual soil moisture. Sorghum-based systems, such as sorghum-pigeon pea or sorghum-chickpea, are typical in black and red soils of Karnataka, Andhra Pradesh, and Tamil Nadu. These systems rely on natural rainfall and are often intercropped with legumes to enhance soil nitrogen and reduce pest pressure.

(b) Production Technology of Rainfed Cotton

(i) Climate and Soil Requirement Rainfed cotton requires a warm climate with a frost-free period of at least 180 days. It thrives with 600–1200 mm of well-distributed rainfall, with the critical period being during boll development. The ideal soil is deep, well-drained black cotton soil (Vertisols) with a pH of 6.5–8.0. These soils have high water-holding capacity, which is crucial for buffering against monsoon gaps.

(ii) Methods of Sowing and Seed Rate Sowing is typically done in June-July, coinciding with the onset of monsoon. Methods include dibbling (manual or mechanical) and drilling. Broadcasting is discouraged as it complicates weeding and thinning. The seed rate varies significantly by variety type. For hybrid cotton, the recommended seed rate is low, approximately 1.5–3 kg/ha (delinted to fuzzy seed), due to high germination and vigor. For open-pollinated (desi) varieties, the rate is higher, around 10–15 kg/ha. Spacing is generally maintained at 90 cm between rows and 30–45 cm between plants.

(iii) Manures and Fertilizers Nutrient management in rainfed cotton is conservative to avoid leaching. Application of 10–15 t/ha of Farm Yard Manure (FYM) is recommended to improve soil organic matter and water retention. The fertilizer dose is lower than in irrigated systems, typically 60–80:30–40:30–40 kg/ha of NPK. Nitrogen is applied in two splits, while phosphorus and potassium are applied as basal doses. Micronutrient deficiencies, particularly Zinc (Zn) and Boron (B), are common in black soils and should be corrected through soil testing and foliar sprays.

(iv) Inter-culture Operations Timely inter-culture operations are critical for weed control and root development. Thinning is done 15–20 days after sowing to maintain plant population. Gap filling ensures uniform stand. Hoeing is performed 2–3 times during the early growth stages to control weeds and aerate the soil. Chemical weed control using pre-plant or pre-emergence herbicides such as fluchloralin (pre-plant incorporated) or pendimethalin can be used, but hand weeding remains essential in rainfed conditions where herbicide efficacy may vary with moisture.

(v) Plant Protection Rainfed cotton is susceptible to pests and diseases. Major pests include bollworms (Helicoverpa armigera and the pink bollworm Pectinophora gossypiella, which has overcome Bt protection in many areas) and sucking pests like whitefly and aphids. Diseases like wilt (Fusarium) and leaf curl virus (transmitted by whitefly) are significant. An Integrated Pest Management (IPM) approach is recommended, involving the use of pheromone traps, yellow sticky traps, and selective insecticides only when economic thresholds are crossed. Biological control agents like Trichogramma spp. can also be deployed.

(c) In Situ Moisture Conservation Practices in Dryland Areas

In dryland areas, in situ moisture conservation aims to reduce runoff and increase infiltration. Contour bunding and graded bunding are structural measures to slow down water flow on slopes. Bench terracing is used in hilly regions to create flat steps for cultivation. Tied ridging involves making ridges across the slope joined at intervals by small cross-ties to trap water. Mulching with crop residues or plastic sheets reduces evaporation. Conservation tillage minimizes soil disturbance, preserving soil structure and moisture. These practices are often integrated with watershed development programs under schemes like PMKSY (Pradhan Mantri Krishi Sinchayee Yojana) to enhance water use efficiency.