Why is there a need for varietal improvement?

Cultivation practices and crop yield are related to environmental conditions. Explain.

Find out the correct sentence:
$(i)$ Hybridisation means crossing between genetically dissimilar plants.
$(ii)$ Cross between two varieties is called as inter-varietal hybridisation.
$(iii)$ Introducing genes of desired character into a plant gives genetically modified crop.
$(iv)$ Cross between plants of two species is called as inter-specific hybridisation.

$(a)$ What do the terms 'macronutrients' and 'micronutrients' signify?
$(b)$ Briefly describe the formation of vermicompost and green manure.

Name any one method of incorporating desirable characters into a crop variety.

India is a country where three-fourths of the population is engaged in agriculture. Even though the financial conditions of some farmers allow them to adopt higher-level farming practices and improved agricultural technology,they are hesitant to use $HYV$ seeds with traits such as resistance to diseases and pests,or qualities that would result in higher yields.
$(a)$ What is meant by genetically modified crops?
$(b)$ What are the desired agronomic characters for fodder and cereal crops?
$(c)$ In your opinion,what should be done so that modern agricultural technology is adopted by most farmers?