Fill in the blanks and chose the correct option given below.

(i) During the digestion in anaerobic sludge digester, bacteria produce a mixture of gases such as , hydrogen sulphide and carbon dioxide. These gases forms .

(ii) The Ministry of Environment and Forests has initiated and to save the major rivers of our country from pollution.

(iii) The technology of biogas production was developed in India mainly due to efforts of and Khadi and .

(iv) The microbial biocontrol agents used to control butterfly caterpillars is the bacteria . When insect eats spore of this bacterium, the toxin is released in of larvae and larva is killed.

(v) are pathogens that attack insects and other arthropods. The majority of them used as biological control agents are in the genus .

(vi) In paddy fields, serve as an important biofertilizer.

(vii) The nodules on the roots of leguminous plants are formed by the symbiotic association of .

(viii) Microbes can also be used to kill harmful pests, a process called as .

(ix) The symbiotic association form between some fungi and plants are called .

(x) Many members of the genus form mycorrhiza.