CBSE Class 9 Answered

Cultivation practices and crop yield are related to weather conditions. Because weather conditions such as drought and food situations are unpredictable, varieties that can be grown in diverse climatic conditions are useful.

Some of the factors for which variety improvement is done are:

(i)Higher yield: To increase the productivity of the crop per acre.

(ii)Improved Quality: Quality of crop products varies from crop to crop like baking quality is important for crops such as wheat.

(iii)Biotic and abiotic resistance: Crop production can decrease due to biotic and abiotic stresses under different conditions. Varieties resistant to these stresses can improve crop production.