Fill in the blanks:
$(a)$ Pigeon pea is a good source of . . . . . . .
$(b)$ Berseem is an important . . . . . . crop.
$(c)$ The crops which are grown in the rainy season are called . . . . . . crops.
$(d)$ . . . . . . are rich in vitamins.
$(e)$ . . . . . . crop grows in the winter season.

Arrange these statements in the correct sequence for the preparation of green manure.
$(a)$ Green plants are decomposed in the soil.
$(b)$ Green plants are cultivated for preparing manure or crop plant parts are used.
$(c)$ Plants are ploughed and mixed into the soil.
$(d)$ After decomposition,it becomes green manure.

Which one is an oil-yielding plant among the following?

The figure shows two crop fields [Plots $A$ and $B$] that have been treated with manures and chemical fertilizers,respectively,while keeping other environmental factors constant. Observe the graph and answer the following questions.
$(i)$ Why does plot $B$ show a sudden increase and then a gradual decrease in yield?
$(ii)$ Why is the highest peak in the plot $A$ graph slightly delayed?
$(iii)$ What is the reason for the different patterns of the two graphs?

To get a better yield,Jaikishan increased the use of pesticides and fertilizers. Though in the initial years he got higher yield,after that,it declined. He was much worried. His friend Mahesh persuaded him to abandon this practice and start using organic manure.
$(i)$ Why are fertilizers used in a field?
$(ii)$ State the possible reason for the decline in yield.
$(iii)$ List two values shown by Mahesh.

Farmer $X$ planted Soyabean $+$ Maize $+$ Cowpeas in the same field simultaneously in a set row pattern. Farmer $Y$ planted cereal crop in one season and leguminous plants in the next season on the same piece of land in pre-planned succession. $(a)$ Name the cropping patterns used by farmers $X$ and $Y$. $(b)$ State two advantages of the different cropping patterns followed by farmers $X$ and $Y$ respectively.