POTENTIAL BENEFITS OF HERBIVORE BEHAVIOR INDUCING AMELIORATION OF FOOD-PLANT QUALITY

Herbivore damage can elicit various kinds of responses in the host pla nt. The responses range from a deterioration (inducible resistance) to an improvement of foliage quality as a food resource of herbivores (i nducible amelioration). Inducible resistance may well have an adaptive significance for the host plant, while the status of inducible amelio ration is far less obvious. Inducible amelioration may, for instance, result from chemical changes associated with compensatory regrowth aft er physical damage. However, it may well be advantageous for a herbivo re to ameliorate the host plant. This is especially so if amelioration does not imply a fitness cost for the herbivore, or if amelioration o ccurs rapidly after damage and the inducer itself gains the benefit. I f, on the other hand, amelioration is costly for the herbivore and the plant response is delayed, ameliorative feeding strategy may evolve p rovided that either the inducer itself utilizes the same plant repeate dly or its relatives gain the benefits.