26. Most of the plants obtain nitrogen from the soil in the from of

1. 1. Free nitrogen gas

   
   
   

   2. Nitric acid

   
   
   

   3. Nitrites

   
   
   

   4. Nitrates

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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27. Sulpuhur is absorbed by plant as

1. 1. SO₃ from soil

   
   
   

   2. SO₂ from air

   
   
   

   3. SO from soil

   
   
   

   4. Both (b) and (c)

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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28. Deficiency of magnesium causes

1. 1. Necrosis

   
   
   

   2. Plasmolysis

   
   
   

   3. Hydrolysis

   
   
   

   4. Chlorosis

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: D

   N/A

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29. Claviceps purpurea is the causal organism of

1. 1. Smut of barley

   
   
   

   2. Erogotism of rye

   
   
   

   3. Powdery mildew of pea

   
   
   

   4. Rust of wheat

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

   N/A

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30. The scientist who studied about wheat rust problem is/are

1. 1. H.C. Bose

   
   
   

   2. K.C. Pant

   
   
   

   3. Birbal Shani

   
   
   

   4. D.D. Pant

   
   
   

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1. View Hint View Answer Discuss in Forum

   N/A

   Correct Option: B

   N/A

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