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Identify the option that has correct sta...

Identify the option that has correct statements regarding biofertilizers.
a. Rhizobium and azotobacter are symbiotic microorganisms.
b. Azospirullum and blue-green algae are non - synbiotic microorganisms .
c. Mycorrhizae is the symbiotic phosphate solubilizing organism.
d. Actinomycetes is the non-symbiotic nitrogen-fixing microorganism.

A

a and b are correct

B

a and d are correct

C

b and c are correct

D

b and d are correct

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding the correct statements about biofertilizers, we will analyze each option step by step. ### Step 1: Analyze Option A **Statement:** Rhizobium and Azotobacter are symbiotic microorganisms. **Analysis:** - **Rhizobium** is indeed a symbiotic microorganism that forms a mutualistic relationship with leguminous plants, helping them fix nitrogen. - **Azotobacter**, on the other hand, is a free-living, non-symbiotic nitrogen-fixing bacterium. **Conclusion:** This statement is **incorrect**. ### Step 2: Analyze Option B **Statement:** Azospirillum and blue-green algae are non-symbiotic microorganisms. **Analysis:** - **Azospirillum** is a free-living nitrogen-fixing bacterium, which does not form symbiotic relationships with plants. - **Blue-green algae** (also known as cyanobacteria) like Anabaena and Nostoc are also free-living and do not have a symbiotic relationship with plants. **Conclusion:** This statement is **correct**. ### Step 3: Analyze Option C **Statement:** Mycorrhizae is the symbiotic phosphate solubilizing organism. **Analysis:** - **Mycorrhizae** are fungi that form symbiotic relationships with plant roots. They enhance nutrient uptake, particularly phosphorus, from the soil for the plants. **Conclusion:** This statement is **correct**. ### Step 4: Analyze Option D **Statement:** Actinomycetes is the non-symbiotic nitrogen-fixing microorganism. **Analysis:** - **Actinomycetes** are a group of bacteria that can fix nitrogen, but they are not typically classified as non-symbiotic. Some species can form symbiotic relationships, while others are free-living. Thus, this statement is misleading. **Conclusion:** This statement is **incorrect**. ### Final Conclusion Based on the analysis: - **Correct Statements:** B and C - **Incorrect Statements:** A and D Therefore, the correct options regarding biofertilizers are **B and C**.
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