Effects of Changing the Phosphorus Content of the Food Plant on the Migratory Grasshopper, Melanoplus bilituratus (Walker) (Orthoptera: Acrididae)

Abstract

It has been demonstrated that changes in the composition of a plant influence the insects that feed upon the plant (Lipke and Fraenkel, 1956). The quantitative composition of plants can be changed by the use of fertilizers (Mulder, 1950; Rennie, 1956), and populations of insects feeding on the plants may increase or decrease (Daniels, 1957; Adkisson, 1958; Joyce, 1958). These changes in numbers of insects have been attributed to such factors as changes in nitrogen, protein, and carbohydrate content (Evans, 1938; Fritzsche et al., 1957) or various mineral constituents (Creighton, 1938).

Dietary phosphate affects food selection, post-ingestive P fate, and performance of a polyphagous herbivore

“…However, diets with a P content of 0.1% and below or 1% and above could support maximal growth during 3 day time periods when animals had been fed on the optimal (0.5%) diets for most of their lives, suggesting insects have a considerable capacity to buffer effects of non-optimal P consumption. Long-term consumption of diets with a P content of 1.00% or higher suppressed growth, consistent with the 'intake target' behavior of S. americana and with observations of reduced performance of various aquatic consumers (Boersma and Elser, 2006) and some insect species when provided with diets well above the mean P levels for terrestrial leaves (Harrison et al, 2014;Loaiza et al, 2008;Smith, 1960). Together, these results demonstrate that ecologically relevant variation in plant P content affects the behavior and performance of this grasshopper.…”

“…Possibly, body P stores compensated for short-term shortages of dietary P. Insects can increase body P in response to higher dietary P; Manduca sexta caterpillars and M. bivittatus grasshoppers had 40-50% higher body P content on higher P foods (Perkins et al, 2004;Smith, 1960), while house crickets increased body P by 10-15% when raised on higher P diets (Visanuvimol and Bertram, 2011). A similar temporal decoupling of dietary P effects has been reported for Daphnia (Sterner and Schwalbach, 2001).…”

“…However, the development rate of the grasshopper Melanoplus bivittatus was unaffected by dietary %P of artificial diets, except for negative effects at the highest levels (Loaiza et al, 2008). Smith (1960) found similar results for M. bivittatus using fertilized wheat, as did Harrison et al (2014), who found no effects of dietary P intake on most fitness parameters of crickets (Gryllus veletis) except for some negative effects of high dietary P on male chirping rate. Finally, fertilization of plots with phosphate increased survival, body size and development rate of one planthopper species but not another (Huberty and Denno, 2006).…”

“…Loaiza et al (2008) found negative effects of high-P synthetic diets (1.74-2.07%P) on the development rate of M. bivittatus. An earlier study reported decreased survival and growth when M. bivittatus nymphs were fed P-fertilized wheat (1.86%P) (Smith, 1960) and suggested that, perhaps counter-intuitively, P fertilizer could be a way to improve wheat crops and decrease pests. These results fit with a growing body of literature showing cases in nature where herbivores may not be N or P limited and that high levels of these nutrients can decrease growth and survival (Boersma and Elser, 2006;Cease et al, 2012;Simpson and Raubenheimer, 2012).…”

“…These results fit with a growing body of literature showing cases in nature where herbivores may not be N or P limited and that high levels of these nutrients can decrease growth and survival (Boersma and Elser, 2006;Cease et al, 2012;Simpson and Raubenheimer, 2012). On the lower end of the P diets, Smith (1960) reported that the low-P wheat (0.17%P) decreased survival relative to control wheat. Loaiza et al (2008) found no negative effect of low dietary P; however, the lowest level of dietary P tested in their experiment was 0.34%, and these tests were run only for one instar (the fifth).…”