Biological Performance and Preference of Mahanarva spectabilis (Hemiptera: Cercopidae) for Feeding on Different Forage Plants

Abstract

The performance and preference of Mahanarva spectabilis (Distant) for feeding on different forage species were evaluated. The survival and duration of the nymphal period, longevity and fertility of adults, and food preferences (free choice) of adults of M. spectabilis were evaluated in a greenhouse trial, and food preferences of adults were also evaluated in laboratory tests without a choice of host plant. In the field, the numbers of plants with spittle masses were evaluated by forage sampling. Lower levels of nymph survival were observed in the greenhouse on Molasses grass, Jaraguá, Tanzânia, and Makueni. The duration of the nymphal period did not differ significantly on different forage species; however, the longevity and fertility of adults were significantly lower on Cynodon and Brachiaria decumbens Stapf. In the free-choice preference test, adult insects were attracted most strongly to B. decumbens and Jaraguá, with intermediate attraction to Brachiaria brizantha (Hochst ex A. Rich) Stapf and Pioneiro. In the test without host choice, insects exhibited lower excretion rates on Tanzânia, Cynodon, Jaraguá, B. brizantha, and Molasses grass, and those fed on Cynodon, Jaraguá, Molasses grass, and Makueni also exhibited reduced body mass. In the field, Pioneiro had the highest number of spittle masses, followed by Roxo de Botucatu. Thus, Molasses grass, Tanzânia, Makueni, and Jaraguá plants are less suitable food sources for M. spectabilis nymphs and adults. Additionally, although Jaraguá was less favorable to nymphs, it attracted food-seeking adults; hence, these plants have potential for use in control of M. spectabilis.

Olfactory response of Mahanarva spectabilis (Hemiptera: Cercopidae) to volatile organic compounds from forage grasses

“…spectabilis for these cultivars, as suggested by Silva et al . 7 , who proved the insect attraction to Basilisk in a greenhouse and to Pioneiro in both a greenhouse and in the field. Insect attraction to released volatiles suggests that they receive information from the plants to detect adequate food sources for their survival.…”

“…This fact is corroborated by the susceptibility of plants to nymphs and adults of this species, as demonstrated by Silva et al . 7 .…”

“…Previous greenhouse studies have also revealed that after one hour of infestation by M . spectabilis , Marandú was ignored for feeding and was hardly considered attractive in the field 7 . Other studies have also shown low attraction of herbivore insects to plants infested by cospecifics.…”

“…spectabilis Silva et al . 7 revealed antixenosis or nonpreference resistance mechanisms of Melinis minutiflora and Panicum maximum cv. Makueni and Tanzânia against M .…”

Do silicon and nitric oxide induce resistance to Mahanarva spectabilis (Hemiptera: Cercopidae) in forage grasses?

“…Spittlebug species of the genus Mahanarva are crucial pests in Brazilian pastures, particularly the species Mahanarva spectabilis (Distant, 1909) (Hemiptera: Cercopidae) . As sucking insects, spittlebugs cause damage by sucking the xylem sap and injecting salivary secretions into the vegetative tissue, leading to leaf death .…”