Which one of the following is not a micronutrient?

1. Molybdenum

2. Magnesium

3. Zinc

4. Boron

A plant requires magnesium for

1. holding cells together

2. protein synthesis

3. chlorophyll synthesis

4. cell wall development

An element playing important role in nitrogen fixation is

1. molybdenum

2. copper

3. manganese

4. zinc

The free-living, anaerobic nitrogen-fixer is

1. Beijerinckia

2. Rhodospirillum

3. Rhizobium

4. Azotobacter

Which one of the following elements is not an essential micronutrient for plant growth?

1. Mn

2. Zn

3. Cu

4. Ca

An organism used as a biofertilizer for raising soyabean crop is

1. Azospirillum

2. Rhizobium

3. Nostoc

4. Azotobacter

Which of the following is a symbiotic nitrogen fixer?

1. Glomus

2. Azotobacter

3. Frankia

4. Azolla

About 98 percent of the mass of every living organism is composed of just six elements

including carbon, hydrogen, nitrogen, oxygen and:

1. phosphorus and sulphur

2. sulphur and magnesium

3. magnesium and sodium

4. calcium and phosphorus

The common nitrogen-fixer in paddy fields is

1. Rhizobium

2. Azospirillum

3. Oscillatoria

4. Frankia