Species of wheat that has gone practically out of cultivation in India because of its low productivity and disease susceptibility is:

Correct option is D

The correct answer is (D) Triticum sphaerococcum

Explanation:
• Triticum sphaerococcum, also known as 'Indian Dwarf Wheat,' was once common in North-Western India and Pakistan.
• It has gone practically out of cultivation primarily due to its very low yield potential and high susceptibility to diseases, especially rusts.
• It is characterized by very short, dense spikes and small, rounded grains, but it cannot compete with the high-yielding semi-dwarf varieties introduced during the Green Revolution.

Information Booster:
• Triticum aestivum: Bread wheat, occupies about 95% of the total wheat area in India.
• Triticum durum: Macaroni wheat, the second most important species in India (about 4-5% area), mainly grown in Central and South India.
• Triticum dicoccum: Emmer wheat, grown in very limited pockets in Karnataka, Maharashtra, and Tamil Nadu for local consumption (Upma wheat).

Additional Knowledge:
• Option A (T. aestivum) is the dominant commercial wheat species worldwide.
• Option B (T. durum) is preferred for making semolina and pasta products.
• Option C (T. dicoccum) is known for its high fiber content and is gaining interest as a health food, unlike Sphaerococcum which is almost extinct in commercial fields.