13)Rhizobium

A free-living bacterium capable of fixing nitrogen is: (a) Rhizobium (b) Streptococcus (c) Pseudomonas (d) Azotobacter

Select the mismatched pair. (a) Rhizobium - Alfalfa (b) Streptococcus - Statins (c) Frankia - Alnus (d) Trichoderma - Cyclosporin-A

Citric acid is obtained from (A) Aspergillus niger (B) Rhizobium nigricans (C) Penicillium citrinum (D) Lactobacillus vulgaricus

Yield of soybean and red gram could be increased by employing the following as biofertilizer (I) Glomus (II) Azospirillum (III) Cyanobacteria (IV) Rhizobium

Which of the following is free-living aerobic non-photosynthetic nitrogen fixing bacterium (A) Anabaena (B) Azospirillium (C) Azotobacter (D) Rhizobium

Read the following statements and select the correct answer. (i). Rhizobium leguminosarum is also known as Bacillus radicicola. (ii). Nitrifying bacteria (Nitrosomonas, etc.) are chemoautotrops. (iii). Enzyme nitrogenase fixes N_(2) under aerobic condition. (iv). Leghaemoglobin creates aerobic conditions for the enzyme nitrogenase.

Select the incorrect statement from the following. (a) Rhizobium multiply and colonises the surroundings of roots and gets attached to epidermal and root hair cell. (b) Successful infection of the root hair causes it to curl . (c) The nodule establishes a direct Vascular connection with the host . (d) Infection thread carries the bacteria to xylem and phloem .

Study the given figure which shows the development of root nodules in soyabean. Match the correct explanation and find the correct sequence for labelled diagrams. (I) Rhizobium bacteria contacting a susceptible root hair. (II) A mature nodule having vascular connection with roots. (III). Infection thread carrying bacteria to the inner cortex. (IV). Curling of root hair due to successful infection.

Which of the following statements about the nitrogen cycle are false ? 1. Rhizobium and Frankia cause nitrogen fixation in their independent free - living stage . 2. Azotobacter and Anabaena are anaerobic, symbiotic , free - living , nitrogen fixers. 3. Rhodospirillum is an aerobic , nitrogen -fixing microbe found in the root nodules of legumes . 4. Nitrobacter oxidizes nitrites to nitrates .

What is Rhizobium?