Q.The disease Nosema apis is caused by:

Biocontrol uses microbes, or substances derived from them, to manage pests as a safer alternative to chemical pesticides. A biopesticide is a microbe (or other biological agent) used specifically for pest control; the soil bacterium Bacillus thuringiensis (Bt) is the most widely used example, producing crystalline Cry (delta-endotoxin) proteins during sporulation that, once activated in an insect's alkaline gut, insert into gut-cell membranes and paralyse the digestive tract, starving the insect — the basis of genetically engineered Bt-cotton. Bioweedicides use microbial compounds to destroy weeds selectively (the first, from Phytophthora palmivora in 1981, controls strangler vine). Trichoderma species control plant pathogens in the root ecosystem, and baculoviruses (Nucleopolyhedrovirus) are species-specific viral biocontrol agents against insects and other arthropods. …