The characteristic symptoms of mosaic disease of crops is usually observed on

The characteristic symptoms of mosaic disease of crops are usually observed on the leaves. Mosaic disease is a viral disease that affects various crops, such as tobacco, tomato, cassava, and beans. It is called "mosaic" because it causes a mottled or mosaic-like pattern of discoloration on the leaves, which can range from light green to yellow, and to dark green to brown. The mosaic pattern is caused by the virus interfering with the chloroplasts, which affects the plant's ability to photosynthesize, leading to stunted growth, reduced yields, and in severe cases, death.