On what factors do the growth of plants and flowering depend?

Fill in the blanks:
$(a)$ Photoperiod affects the . . . . . . .
$(b)$ Kharif crops are cultivated from . . . . . . to . . . . . . .
$(c)$ Rabi crops are cultivated from . . . . . . to . . . . . . .
$(d)$ Paddy,maize,green gram,and black gram are . . . . . . crops.
$(e)$ Wheat,gram,pea,and mustard are . . . . . . crops.

Why is excess use of fertilizers detrimental for the environment?

Sidak,when visiting a supermarket,was surprised to see yellow,green,and red-coloured capsicum available in the stalls. It was a drastic change in the quality and quantity of capsicum.
$(a)$ What is this change due to?
$(b)$ How are such crops produced?

Why is there a need for varietal improvement?

$A$ farmer had a plot just beside the bank of a river. Each time he planted $Kharif$ crops,the crops got damaged due to floods. He consulted an agricultural scientist who gave him a special variety of seeds and also advised him to practice fish farming.
$(a)$ What was the specialty of these seed grains?
$(b)$ What name can be given to this type of fish farming?