Pesticides and Pest Control

The action threshold is the level of pest population at which control action must be taken to prevent the population from reaching the economic injury level.

Monitoring is a comprehensive process that includes identifying pests, assessing their damage potential, and setting thresholds to guide management decisions.

Integrated pests management is a method which uses the natural agents like the microbes and insects to control the population of other harmful pests and insects. Mechanical control is applied when the pests reach an unacceptable level. This method includes techniques like screens, beating with stick, bagging fruit, sieves, hand-picking, barriers, traps, vacuuming and tillage to disrupt breeding. 

Biological control is a method to control pest by using living microorganisms or its product. It is used as natural enemies like the predators, parasites, pathogens, and competitors to suppress and maintain populations of a target pest species (insects, mites, weeds, plant pathogens, and other pest organisms). This is the most widely used method in today's world for the control of pests. 

Bacillus thuringiensis are bacteria that act as biological insecticide.

Phytophthora palmivora was the active agent in Devine, which was the first registered bioherbicide in 1981. It was used to control milkweed vine in citrus groves.

Third generation pesticides refer to insect growth regulators, specifically juvenile hormone analogues, which disrupt the development of insects rather than killing them directly through toxicity.

The sterile insect technique (SIT) was famously and successfully used to eradicate the New World screw-worm fly from North America by releasing large numbers of sterilized males.

Margosa (Neem) extracts have been used traditionally for centuries as natural pesticides, making them the earliest form of botanical pest control compared to synthetic options like DDT.

Azadirachtin is the primary active limonoid compound found in neem seeds and leaves, widely recognized for its efficacy as an insect repellent and growth disruptor.

Devine and Collego are well-known commercial trade names for bioherbicides. Devine uses Phytophthora palmivora, and Collego uses Colletotrichum gloeosporioides.

Answer is option C i.e. "Marigold"
Biodegradable insecticides are types of insecticides derived from natural materials as plants, bacteria, etc. Bioinsecticide from marigold flowers contains chemicals called thiophenes which are toxic to the larvae of mosquitoes that carry malaria and yellow fever. Bioinsecticide made from marigold also contains repellent against major tomato pests: whiteflies, thrips, and spider mites.

Rotenone is a naturally occurring isoflavone obtained from the roots of several tropical plant species, such as those in the genus Derris, and is used as a botanical insecticide.

Environmental pest control (or ecological control) involves methods like intercropping, trap crops, and biological control agents (predators/parasites). The sterile male technique is considered a genetic or autocidal control method, not an environmental one.

Baculoviruses are used as biological control agents and in intrinsic farming because of all these above characteristics.