What will come in place of (?) in the given expression.

Which of the following nutrients plays an important role in root development?

Which of the following is the most suitable crop to cultivate on heavy black cotton soils, especially under dryland conditions?

According to Prof. Mildred Hurton, the first training group of human race is:

What is the main component of organic matter in soil?

Which of the following exemplifies an integrated farming system?

Monocotyledons flowers do not have distinct sepals or petals. The combined petals and sepals found in them are called 

Which soil order is characterized by a lack of horizon development and is classified under azonal soils?

Match List I with List II

Which of the following weed is total root parasite?

Which one of the following is the error d f for a RCB experiment with six treatments replicated live times?