The relationship among host plant species, egg clutch size, and level of parasitism for the sharpshooter Tapajosa rubromarginata

VIRLA, E.G.; AGUIRRE, MARÍA BELÉN; VAN NIEUWENHOVE, G.A.; LUFT ALBARRACIN, E.; LOGARZO, G. A.

ENTOMOLOGIA EXPERIMENTALIS ET APPLICATA

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2020

0013-8703

The sharpshooter Tapajosa rubromarginata (Hemiptera: Cicadellidae: Proconiini), a vector of Xylella fastidiosa (Xanthomonadales: Xanthomonadaceae) that causes Citrus variegate chlorosis, has more than 30 reported host-plant species. The fitness of a phytophagous insect is determined by the host plant suitability, plant resistance, and the natural enemies. The aim of this contribution was to: 1) identify plant species utilized as oviposition substrate by T. rubromarginata in the field; 2) establish the relationship between plants and clutch size; 3) study the relationship among host plants, clutch size and level of parasitism, and 4) establish variations in parasitoid composition and abundance in the different host-plants. Egg masses of the sharpshooter were surveyed on plants reported as hosts, or those that were abundant in the study site. The number of eggs of the sharpshooter and emerged parasitoids were recorded for all the collected masses. We found egg masses of T. rubromarginata on 12 out of 21 plant species sampled. The size of the egg masses was greatly influenced by the type of leaf venation and to a lesser extent by the plant species. Parasitism rates were influenced by both leaf venation and host-plant. Trichogrammatidae species were mostly associated with egg masses in plants with parallel veined leaves, while Mymaridae attacked masses laid in reticular veined leaves. The choice between a good host plant, but heavily attacked by parasitoids, and the host plants that are less suitable for nymphs but less frequently attacked by natural enemies, was a trade-off for T. rubromarginata females to increase their fitness. We concluded that the host plant utilization by T. rubromarginata females in the field could be influenced by leaf structure and the strategy to avoid parasitism by selecting plants that were less attractive for parasitoids.