The correct answer is Option 4: 1, 2, and 3.
Genome sequencing is the process of determining the complete DNA sequence of an organism`s genome. In agriculture, it can be used for crop improvement by identifying genes responsible for specific desirable traits such as disease resistance and drought tolerance. Here are the reasons why all three options are correct:
1. Genome sequencing can be used to identify genetic markers for disease resistance and drought tolerance in various crop plants: With genome sequencing, scientists can identify specific genetic markers associated with desirable traits such as disease resistance and drought tolerance. This can help plant breeders develop new varieties of crops that are better adapted to local conditions and have higher yields. For instance, in 2019, Indian scientists sequenced the genome of pigeon pea, a crop that is a major source of protein and income for small farmers in India. The researchers identified genes responsible for drought tolerance, which could be used to develop new drought-tolerant varieties of pigeon pea.
2. This technique helps in reducing the time required to develop new varieties of crop plants: Genome sequencing can help plant breeders develop new crop varieties faster than traditional breeding methods. With genome sequencing, scientists can identify specific genes responsible for desirable traits and use this information to breed plants with those traits. This can help reduce the time required to develop new crop varieties from several years to just a few months.
3. It can be used to decipher the host-pathogen relationships in crops: Genome sequencing can also be used to study the interactions between crops and pathogens. By sequencing the genomes of both the pathogen and the host plant, scientists can identify the genes responsible for disease resistance and susceptibility. This information can be used to develop new crop varieties that are resistant to specific diseases. For instance, Indian scientists have used genome sequencing to study the interaction between rice and the fungal pathogen Magnaporthe oryzae, which causes blast disease in rice. The researchers identified genes responsible for disease resistance, which could be used to develop new blast-resistant varieties of rice.
In conclusion, genome sequencing has enormous potential to improve agriculture in India by identifying genetic markers for desirable traits, reducing the time required to develop new crop varieties, and studying the interactions between crops and pathogens.