**3.13 Dry spell management**

In Indian context dry spells occur in monsoon season invariably. The frequency of the dry spell is increasing in current scenario due to climate change. Moisture stress is a resultant of complex set of several climatic, edaphic, and agronomic factors. It can be characterized by major three varying parameters, i.e., occurrence timing, its intensity, and duration. Reduction of tissue water content, stomatal conductance, metabolic processes, and growth are subsequent effects of Dry spell induced a restricted water supply. Plants develop various adaptive mechanisms in response to moisture stress. These adaptations are drought tolerance and avoidance strategies to defy moisture stress. Under drought conditions, Plants by maintaining favorable water status may avoid moisture stress. Plant may avoid drought either by reducing water loss from leaves or by increasing the capacity of roots for water uptake.

Mitigation strategies of dry spell in soybean are:


### **3.14 Soybean based cropping/intercropping systems**

Areas where mean seasonal rainfall is 600–750 mm and the effective growing duration is 20–30 weeks, in that part intercropping is suggested, while the areas having mean annual rainfall more than 750 mm and duration of effective cropping season length is more than 30 weeks, double cropping of soybean is possible. In Madhya Pradesh and Maharashtra, particularly Marathwada region intercropping system of soybean + pigeon pea (4:2 row ratio) is very profitable and is recommended particularly for rainfed cultivation. Early maturing (short duration) pigeon pea varieties are more suitable for intercropping system. Soybean + sorghum or soybean + cotton intercropping is also recommended and practiced on large area in and around Madhya Pradesh (**Tables 2** and **3**).

The soybean-based cropping systems are not only productive but they have been profitable as good energy-efficient under various agro-climatic conditions. It is also advisable to farmers that continuous growing of soybean on the same piece of land should be avoided. Crop rotation tactics should be followed for sustainable soybean production (**Figure 2**) [6].

### **3.15 Conservation agriculture in soybean**

Looking at the sustainability of the natural resources, CA is the promising system. CA is a broad term and it encompasses all conserving techniques that conserve resources anyway. It also involves the following technologies:


### **Table 2.**

*Soybean based remunerative cropping/intercropping system for different zones of India.*


### *Climate-Resilient Technologies for Enhancing Productivity of Soybean in India DOI: http://dx.doi.org/10.5772/intechopen.104603*

### **Table 3.**

*Soybean seed yield (kg/ha), gross monetary returns (GMR), net monitory returns (NMR), benefit cost (BC) ratio and rain water use efficiency (RWUE) as influenced by different treatments (2014–2016).*


Resource conserving techniques confirm the optimal utilization of resources and improve input use efficiency. These practices include reduced tillage or zero tillage or no tillage, integrated crop management approaches, retaining crop residue and Use of beneficial microorganisms helpful in increasing both the biological fertility of soil and crop production. CA practices decrease resource degradation. Slow breakdown of surface residues which recovers soil organic matter status, soil microbial and biological activity, and diversity. These practices also contributes to the overall enhancement in soil quality. Sustainable improvements in efficient use of water and nutrients by improving nutrient balance and availability, infiltration, and retention by the soil, reducing water loss due to evaporation.

### **Figure 2.**

*Soybean + pigeon pea intercropping system in 4:2 row proportion is widely adopted system under rainfed conditions of Marathwada region.*

### **3.16 Minimum/zero tillage**

Minimum tillage is aimed at reducing tillage to the minimum necessary. It ensures a good seedbed, rapid seed germination, a satisfactory plant stand, and promising growing conditions. Minimum tillage will benefit in soil setting, improve soil infiltration, reduce soil resistance and soil compaction along with reduction in soil erosion. Although it has some adverse effects like lower seed germination, additional nitrogen requirement, hampers nodulation in some legumes, requires specially designed implements, development of herbicide residue and its pollution, and the perennial weeds become difficult to control.

Zero tillage is an ultimate form of CT in which mechanical soil manipulation is diminished to traffic and sowing only. In India at present area under zero tillage is 2.0 million ha and potential area is 2.0 million ha and 10 million ha. It is very supportive in the area of intensive cultivation where a turnaround period between two crops is very less and which can facilitate timely sowing. Zero tillage offers the benefit of reduced fuel consumption and labor expenses, reduction of total cost of cultivation,

timely sowing is possible which offers yield advantage, reduced soil loss and erosion ultimately improvement in soil health.

### **3.17 Broad-bed and furrow system**

BBF method comprised of the formation of broad-beds of 135 cm wide and 20 cm elevated beds and divided by 45 cm wide furrows, which are to a depth of 20 cm and graded across the contour to a 0.5% slope [7]. The main purpose of this system is to provide acceptable drainage during heavy rainfall events and draining excess rain water into grassy waterways or farm ponds. This stored rain water will be used to provide supplemental irrigation to Kharif and Rabi crops during dry spells. It will reduce runoff and soil loss, and for in-situ moisture conserving in the furrows. The movement of rain water in BBF system is in both the directions, i.e., vertically downward in furrows and laterally in micro and macro pores in the raised broad beds which enhances the efficient use of rain water.

National Innovations on Climate Resilient Agriculture Project (NICRA) adopted villages in Southern and Central parts of India, farmers who implemented broad bed furrow (BBF) sowing technique in soybean by BBF planter evaded injury to the crop owing to surplus rainfall during *Kharif* seasons of 2013, 2019, 2020, 2021 and gained about 40% yield benefit compared to flatbed sowing. BBF method for, soybean, cotton, pigeon pea and maize saved crop damage due to excess soil moisture by aiding quick drainage and avoiding water stagnation.

**Figure 3.** *Sowing of soybean with BBF planter.*

BBF planter (**Figure 3**) facilitates the simultaneous preparation of broad beds and furrows (for soil and water conservation, in which furrows acting as safe drainage channels during heavy rainfall events (**Figure 4**) sowing of the seed with less seed

### **Figure 4.**

*Furrows acting as safe drainage channels during heavy rainfall events in soybean sown with BBF method.*

**Figure 5.** *Soybean sown with BBF method.*

### *Climate-Resilient Technologies for Enhancing Productivity of Soybean in India DOI: http://dx.doi.org/10.5772/intechopen.104603*

requirement (kg/ha), deep placement of fertilizers below the seed enhancing the fertilizer use efficiency, which reduces the time, labor, energy and cost of cultivation (**Figure 5**).

### **3.18 Crop residue management**

In India about 400 million tons of crop residues are produced annually. A large quantity of crop residues is left in the field when mechanical harvesting is practiced. This crop residue can be recycled which increases the organic carbon content in soil, as well as nutrient supply. About 25% of nitrogen (N) and phosphorus (P), 50% of sulfur (S), and 75% of potassium (K) uptake by cereal crops are retained in crop residues, making them valuable nutrient sources. Mulching with crop residues contributes to the conservation of soil and rainwater (**Figure 6**).

This technique reduces evaporative losses of soil moisture, nutrient loss along with runoff. Contrasting removal or burning of crop residue, incorporation of straw builds up soil from cropped fields. Crop residues modify soil biological activity resulting in improved soil fertility and better soil physical conditions.

Application or retention of crop residue at 2–5 tons/ha will conserve the soil moisture will also help in conservation of soil health.
