wheat variety which introduced earlier as resistence to leaf rust disease but became susceptible to same is ?

1. kalyan sona
2. lerma rojo
3. sonara-64
4. sharbati sonara

The wheat variety you’re referring to is Kalyan Sona. Initially, Kalyan Sona was developed and introduced as a resistant variety to leaf rust disease, which is caused by the fungus Puccinia triticina. However, over time, it has become susceptible to this disease due to various factors, including the evolution of the pathogen and changes in environmental conditions.

Understanding the Context of Wheat Varieties

Wheat is one of the most important staple crops globally, and its production can be significantly affected by diseases like leaf rust. Breeders often develop new varieties that are resistant to specific diseases to enhance yield and sustainability. However, the dynamics of plant-pathogen interactions can change over time.

Resistance and Susceptibility Dynamics

When a new wheat variety is introduced, it may carry specific genes that provide resistance to certain diseases. In the case of Kalyan Sona, it was bred with such resistance traits. However, the pathogens can adapt and evolve, leading to a situation where previously resistant varieties become susceptible. This phenomenon can be attributed to:

• Pathogen Evolution: Fungal pathogens like those causing leaf rust can mutate and develop new strains that can overcome the resistance mechanisms in wheat varieties.
• Monoculture Practices: When a single variety is grown extensively over large areas, it can create a favorable environment for the pathogen to thrive and evolve.
• Environmental Factors: Changes in climate and agricultural practices can also influence the effectiveness of resistance traits.

Examples of Resistance Breakdown

To illustrate this concept, consider the following:

• Wheat Variety Lerma Rojo: Similar to Kalyan Sona, Lerma Rojo was once resistant to certain diseases but has also faced challenges due to evolving pathogen strains.
• Sharbati Sonora: This variety has also been recognized for its resistance, but like Kalyan Sona, it can become susceptible over time as pathogens adapt.

Implications for Wheat Breeding

The situation with Kalyan Sona highlights the importance of continuous breeding efforts. To maintain resistance, breeders must regularly introduce new genetic material and develop varieties that can withstand evolving diseases. This ongoing process is crucial for ensuring food security and sustainable agricultural practices.

In summary, Kalyan Sona serves as a prime example of how resistance can diminish over time due to various factors, emphasizing the need for adaptive strategies in wheat breeding and disease management.