The aquatic fern used to increase the yield in paddy crops is Azolla. Azolla is a floating fern that can fix atmospheric nitrogen, providing a natural source of nitrogen to rice paddies.
So, the correct option is (A): Azolla
List -I | List-II | ||
A | Aspergillus niger | I | Butyric acid |
B | Clostridium butylicum | II | Acetic acid |
C | Saccharomyces cervisiae | III | Citric acid |
D | Acetobacter aceti | IV | Ethanol |
List I | List II | ||
---|---|---|---|
A | Robert May | I | Species-Area relationship |
B | Alexander von Humboldt | II | Long term ecosystem experiment using out door plots |
C | Paul Ehrlich | III | Global species diversity at about 7 million |
D | David Tilman | IV | Rivet popper hypothesis |
List I | List II | ||
---|---|---|---|
A | Mesozoic Era | I | Lower invertebrates |
B | Proterozoic Era | II | Fish & Amphibia |
C | Cenozoic Era | III | Birds & Reptiles |
D | Paleozoic Era | IV | Mammals |
There are several valuable microorganisms that are beneficial to humans in various manners such as: