Sorghum is popularly known as jowar, and is one of the most important food and fodder crop of dryland agriculture. Jowar is mainly concentrated in the peninsular and central India. Maharashtra, Karnataka, Andhra Pradesh, Madhya Pradesh, Gujarat, Rajasthan, Uttar Pradesh (the Bundelkhand region) and Tamil Nadu are the major jowar growing states.
Sorghum grows to a height of 2 to 8 feet, sometimes reaching as high as 15 feet. The leaves are about 5 cm broad and 76 cm long. The tiny flowers are produced in panicles that range from loose to dense. The seeds vary widely among different types in colour, shape, and size, but they are smaller than those of wheat.
Sorghum as green foliage is very popular in north India and is planted during kharif, under irrigated conditions. Multicut sorghum does well under hot and dry climate. It requires well-drained soil and is susceptible to water logging conditions.
The sowing is done in April and August for fodder and June and July for grains in India.
Monsoon and Sorghum Cultivation
Sorghum farming in India has two distinct seasons driven by the monsoonal rainfall, which are the kharif and rabi, while during the third season which is the summer, cropping is feasible, only where an irrigation water source is prevalent.
Indian monsoonal rains are spread across four months, i.e., from June to September, and during this season the range of temperature is optimal. During the post-monsoon it’s the winter temperature extreme on the minimum side that sets the limitation on pollen viability, while, in summer it’s the other extreme of the maximum which influences the seed setting physiological phase.
Importance of Sorghum
Sorghum ranks fifth among the world’s most important crops. More than 70% of the world’s total production of sorghum comes from the developing countries in Asia and Africa, where crop is grown with limited input of water and nutrients.
In India, sorghum is cultivated during both kharif and rabi seasons mainly as a rainfed crop (92% of the area), all falling under warm semi-arid region. Hence, sorghum is one of the major food crops in drought prone environments, but has great potential for crop improvement for food, feed, fodder and bio fuel production (FFFF).
In India, national productivity of sorghum is very low (880 kg/ha), the low productivity can be attributed to low and marginal management and rainfed cultivation.
Impact of climate change on rabi sorghum is likely to reduce the yields up to 7% by 2020, up to 11% by 2050 and up to 32% by 2080.
Sorghum as food crop:
Sorghum food consumption has many potential health benefits such as high anti-oxidant levels, improved cholesterol profiles of the consumer, and as a source of safe food for persons with celiac disease. Sorghum grains have high fibre content, moderate digestibility, rich mineral content compared to other cereals such as rice and wheat.
Market for processed foods such as multigrain flour, flakes, vermicelli, pasta and biscuit is surprisingly picking up in urban areas as there is increasing acceptability of sorghum if available in ready-to-eat form or as convenient foods as health and nutritional foods.
Sorghum as source of feed and fodder:
Dairy industry has been the driving force in the region of Punjab, Haryana, Uttaranchal, Uttar Pradesh, South Rajasthan and North West Gujarat. In Deccan Plateau, where sorghum grain is more important, there is a need to improve the stover quality to support dairy industry.
Sorghum as bio-fuel crop:
Sorghum has a potential to emerge as one the important crop in the tropics that supply biofuel such as ethanol, the demand for which “far exceeds the supply” on the world market.
Sweet sorghum has emerged as a supplementary crop to sugarcane in dry land pockets for the production of ethanol. The advantages of the crop are it can be grown with limited water and minimal inputs and it can be harvested in four months with 2-3 irrigations.
Use of ethanol blended fuel is increasing because they reduce vehicular emission of CO2, methane and other gases that contribute global warming.
The dual-purpose nature of sweet sorghums—they produce both grain and sugar-rich stalks—offers new market opportunities for smallholder farmers and does not threaten food, feed and fodder value of sorghum.
As sweet sorghum requires less water and has a higher fermentable sugar content than sugarcane, it is better suited for ethanol production than sugarcane or other sources, and sweet sorghum ethanol is cleaner than sugarcane ethanol, when mixed with gasoline.
Sorghum crop has a unique inbuilt ability of biological nitrification inhibition (BNI) in its root exudates through which it suppresses nitrification in soil. This indicates that sorghum can play a vital role in mitigating the impact of global warming by regulating the emission of greenhouse gases like nitrous oxide N2O, CO2 and methane.
Conclusion –
Sorghum is a multi-functional crop and hereditary higher tolerance to heat, drought, salinity etc. Therefore, this crop has a better chance to get adapted to these supra-optimal conditions. The quality of research needs to be improved for sorghum cultivation and proper extension need to be carried out to make farmers aware of this crop.