Carter, W., & Schmidt, C.T. 1935 Mass action phenomena in mealybug wilt.. Annals of the Entomological Society of America 28(3): 396-403.

Notes: In an experiment on the relationship between numbers of mealybugs applied and resulting wilt of pineapple plants 3,130 plants were infested with mealybugs (Pseudococcus brevipes (Ckll.)) varying in number from 1 to 40 and 3,151 check plants were observed. It has been shown that the separation of mass action phenomena from those of incidence of toxic individuals by statistical methods is difficult but wilt in the plots infested with one mealybug per plant was not statistically significant when compared with that developing in the check plots. From this it is concluded that under the conditions of plant susceptibility prevailing at the time, the most susceptible plant required a toxic dose grater than that provided by the feeding of one mealybug. The biology of the insect and field observations on its occurrence provide additional evidence against the hypothesis that wilt is the result of the incidence of toxic individuals. The datum on the factor of mass action is indicative but other experimental approaches will be necessary before this factor can be adequately evaluated.