Explanation:

Ans. Photo insensitivity 

Sunflower is a drought tolerant crop due to its deep tap root therefore it is the best substitute to all rainfed commercial crops. This can be grown in rabi and summer as I.D crop with higher yield.

It is the best substitute for delayed kharif sowing due to delayed onset of monsoon which is very common phenomenon.

Because of its short duration nature it can be incorporated in any type of cropping system.

Seed cost is very low when compared with groundnut (Roughly cost of groundnut seed/ha is Rs. 2,2250/-) an important oil seed of A.P.

Sunflower can be profitably cultivated with less expenditure, limited water, easy cultivation methods, hence small and marginal farmers can take up this crop easily and profitably.

Sunflower can be comes to harvest 10-15 days earlier to groundnut. Water requirement, seed requirement (interms of cost also) and cost of cultivation is much less in sunflower over groundnut.

Sunflower is a photo-intensive crop, hence, can be grown throughout the year if water is available. But the duration will be extended in winter season or in cold climates.

As in other crops no flower drop is seen in sunflower. This may be one of the reasons for more ill filled grains in this crop.

Suitable varieties and hybrids are available suit our climatic conditions.

Sunflower is an errect growing plant and hence, no shade effect on the component crop if it is grown as an inter crop.