Sorghum is a versatile cereal crop that is widely grown across the globe. This drought-tolerant crop is an important source of food, feed, fodder, and fuel for millions of people, particularly in the arid and semi-arid regions of Africa, Asia, and Latin America. Over the years, sorghum researchers and breeders have developed numerous improved varieties of sorghum that exhibit various desirable traits such as high yield potential, disease and pest resistance, drought tolerance, and good grain quality.
One of the major ways in which sorghum breeders have improved sorghum varieties is through hybridization. By crossing two or more different sorghum varieties, breeders can create offspring with desirable characteristics that exhibit hybrid vigor or heterosis. Hybrid sorghum varieties are often more productive, uniform, and resistant to environmental stress than their parent lines.
Another method of improving sorghum varieties is through genetic modification. By introducing genes from other plants or animals, sorghum breeders can enhance or introduce new traits in sorghum, such as herbicide resistance, insect resistance, and increased protein content. Genetically modified or transgenic sorghum varieties are often controversial, however, due to concerns about their potential impacts on the environment and human health.
In addition to hybridization and genetic modification, sorghum breeders have also improved sorghum varieties through traditional breeding methods, such as selection and mutation breeding. These methods involve selecting or inducing mutations in existing sorghum varieties that exhibit desirable traits, such as shorter stature, increased grain size, and improved disease resistance. These improved varieties are then propagated and distributed to farmers, often with the help of agricultural extension services.
Some of the improved varieties of sorghum that have gained popularity among farmers and consumers include:
1. IS 18551-5: This hybrid sorghum variety is known for its high yield potential and drought tolerance. It also exhibits resistance to pests and diseases, making it a preferred choice for farmers in drought-prone regions of India.
2. SC 56: This traditional sorghum variety is a favorite among sorghum farmers in East Africa due to its excellent grain quality and high protein content. It is also resistant to Striga weed, a parasitic weed that is notorious for reducing sorghum yields in sub-Saharan Africa.
3. Soubatimi: This hybrid sorghum variety is widely grown in West Africa due to its early maturity and good grain quality. It is also resistant to bird damage, a common problem that affects sorghum yields in the region.
4. BTx 623: This transgenic sorghum variety was developed by introducing a bacterial gene that confers herbicide resistance. It has been shown to increase sorghum yields and reduce labor costs for weed control.
In conclusion, improved varieties of sorghum have played a significant role in increasing global sorghum productivity and enhancing food security in many developing countries. However, the sustainability and safety of these improved varieties should be carefully evaluated to ensure that they have minimal negative impacts on the environment and human health.