Plant secondary substances and insects behaviour

Allelochemicals are storing in different location in plant tissues as inactive form. Number of identified compounds may now exceed 100,000. Environmental factors have an effect on allelochemicals concentration in plants. Many allelochemicals classified as toxins or deterrents for herbivorous insects. Allelochemicals play a major role in feeding or ovipositing stimulants for some specialist insects. Consumption and assimilation of herbivorous insects had affected by the type of allelochemicals in host plants. Allelochemicals have an acute or chronic toxicity on herbivorous insects. Most specialist herbivorous insects rely heavily of ingested plant allelochemicals. Plant allelochemicals may influence an insect's susceptibility to pathogens such as bacteria, fungi and nematode. Specialists herbivorous insect can be using the allelochemicals in their host plants as protection against natural enemies. Some herbivorous insects are synthesising the aggregation, attracting, alarm or mating pheromone from the allelochemicals in their host plants.