2‐Alkyl‐3‐methoxypyrazines are potent attractants of florivorous scarabs (Melolonthidae, Cyclocephalini) associated with economically exploitable Neotropical palms (Arecaceae)

Abstract

The identification of MPs as potent kairomones could prove instrumental in integrated pest management plans for these insects in emerging oil-yielding crops in South America, including those of the wine palm (Att. butyracea) and macaw palms (Acrocomia spp.). © 2018 Society of Chemical Industry.

Novel Floral Scent Compounds from Night-Blooming Araceae Pollinated by Cyclocephaline Scarabs (Melolonthidae, Cyclocephalini)

“…The unique structure of these floral VOCs and their biosynthesis in large amounts imply selective evolutionary pressure exerted by scent-oriented pollinators (Raguso 2008 ; Schiestl and Johnson 2013 ). Contrastingly to more widespread floral scent constituents, such as 5 , 6 , and 7 , they might function as specific communication cues to lure certain species of cyclocephaline scarabs, an assumption supported by the fact that other rare or uncommon floral VOCs identified in the perfumes of Neotropical night-blooming Araceae proved to be attractants of these anthophilous insects (Dötterl et al 2012 ; Gottsberger et al 2012 ; Maia et al 2012 , 2013 , 2018 ; Pereira et al 2014 ). In a study conducted in the Atlantic Forest of southeastern Brazil, Gottsberger et al ( 2013 ) showed that synchronous flowering populations of three different species of Thaumathophylum within a ca.…”

“…Recent studies about the reproductive ecology of night-blooming Neotropical angiosperms have shown that VOCs derived from a number of different biosynthetic metabolic pathways are implicated with the attraction of cyclocephaline scarabs (Melolonthidae, Cyclocephalini), a diverse group of highly specialized anthophilous insects (Moore et al 2018 ). Among such compounds are cis -jasmone ( 5 ), 4-methyl-5-vinylthiazole (Maia et al 2012 ), ( S )-2-hydroxy-5-methylhexan-3-one (Maia et al 2013 ), 4-vinylanisole (Dötterl et al 2012 ), dihydro-β-ionone (Pereira et al 2014 ), methyl 2-methylbutyrate (Gottsberger et al 2012 ), and 2-alkyl-3-methoxypyrazines (Maia et al 2018 ). Either alone or in simple combinations with other constituents, these VOCs are selectively attractive to species belonging to the genera Cyclocephala Dejean, 1821 and Erioscelis Burmeister, 1847.…”

Chemical ecology of Cyclocephala forsteri (Melolonthidae), a threat to macauba oil palm cultivars (Acrocomia aculeata, Arecaceae)

“…One of the main concerns of large‐scale monoculture exploitation is an increased risk of the establishment of pests, which can be particularly worrisome in perennial fruticultures (Simon, Bouvier, Debras, & Sauphanor, ). Palm crops seem to be prone to the attack of florivorous insects (Moore, ), and in the neotropics, cyclocephaline scarabs (Melolonthidae, Cyclocephalini) are among the most common florivores associated with them (Maia, Santos, Gonçalves, Navarro, & Nuñez‐Avellaneda, ; Moore & Jameson, ). One particular species, Cyclocephala forsteri Endrödi, 1963 (Figure S1a), is a persistent visitor of the inflorescences of the macauba palm in South America (Oliveira & Ávila, ).…”

“…Analogously to what is known for other species of cyclocephaline scarabs, it is assumed that both female and male C. forsteri are driven to the night‐blooming inflorescences of macauba palms by specific floral volatile compounds (VOCs), profusely emitted during anthesis. So far, seven VOCs have been identified as kairomone attractants for these insects (Maia et al, , ; Pereira et al, ), and based on the high rates of capture observed in previous studies (Maia et al, ), we assume that effective pest management plans for C. forsteri could greatly benefit from the elucidation of the following questions: (a) What are the chemical cues behind the attraction of C. forsteri to inflorescences of macauba palms? (b) Can these kairomones be used for selective attraction of C. forsteri ?…”

(3S,6E)-Nerolidol-mediated rendezvous of Cyclocephalini beetles,Cyclocephala paraguayensis, in bottle gourd flowers

“…The floral volatile organic compounds (VOCs) in the plant families of Araceae, Annonaceae, Arecaceae, and Magnoliaceae, have been demonstrated to be comprised of pyrazines, ketones, esters, and methoxystyrenes [8][9][10][11][12][13]. By contrast, VOCs produced by eudicot flowers that are visited by Cyclocephalini beetles of the genus Cyclocephala have never been identified.…”