NÃO-PREFERÊNCIA PARA A OVIPOSIÇÃO DE PERCEVEJO-DE- RENDA Vatiga illudens (Hemiptera: Tingidae) POR CULTIVARES DE MANDIOCA

Abstract

RESUMOO objetivo desse trabalho foi avaliar a não preferência para a oviposição de Vatiga illudens (Drake, 1922) (Hemiptera: Tingidae) importante inseto com potencial de causar danos econômicos em cultivares de mandioca. Compararam-se as cultivares Kiriris, N-25, Fécula Branca, IAC 90, M Ecu 72 e IAC 576, essas com potencial produtivo para a região sul de Mato Grosso do Sul. Foram realizados ensaios de preferência para oviposição, com o teste sem chance de escolha, em condições de semi-campo. Um casal adulto de V. illudens foi liberado nas folhas de mandioca das respectivas cultivares. Permitiu-se a alimentação e oviposição desses insetos por 72 horas. Avaliou-se o número de ovos/fêmea/folha, o número de excrementos/casal/folha e o índice de preferência para oviposição. A cultivar M Ecu 72 revelou-se altamente resistente ao percevejo-de-renda. Esse estudo evidenciou que há mecanismos de resistência a V. illudens em cultivares de mandioca, o que justifica a realização de novos estudos sobre essas cultivares em programas de seleção, visando o controle dessa praga e identificação de tais mecanismos.Palavras-Chave: antixenose, insecta, resistência de plantas. ABSTRACTThe aim of this study was to evaluate the non-preference for oviposition Vatiga illudens (Drake, 1922) (Hemiptera: Tingidae) in cassava cultivars. The following cultivars were compared: Kiriris, N-25, Fécula Branca, IAC 90, M Ecu 72 and IAC 576, preference tests for oviposition were conducted, with a choice test in semi-field conditions. An adult double V. illudens was released in the leaves of cassava of their cultivars. Allowed to feeding and oviposition of these insects for 72 hours. We evaluated the number of eggs / female / leaf, the number of droppings / couple / sheet and the preference index for oviposition. The cultivar M Ecu 72 demonstrated to be highly resistant to cassava lace bug. This study showed that there are resistance mechanisms to V. illudens in cassava cultivars, which justifies the new studies on these cultivars in breeding programs, aiming to control this pest and identification of such mechanisms.

Predicting the potential invasion suitability of regions to cassava lacebug pests (Heteroptera: Tingidae: Vatiga spp.)

“…Leaves have yellowish stains, which later become reddish-brown. Sucking of the sap by the bugs weakens the plant and reduces its photosynthetic capacity, favoring the premature fall of basal leaves (Oliveira et al , 2001; Moreira et al , 2006). Few studies have evaluated the consequences of Vatiga spp.…”

“…Its five species are sympatric and feed exclusively on cassava (Froeschner, 1993). The species most frequently recorded as cassava pests are Vatiga illudens (Drake) and Vatiga manihotae (Drake), which are exhaustively mentioned in the literature (Oliveira et al , 2001; Moreira et al , 2006; De Paula-Moraes et al , 2007; Fialho et al , 2009; Halbert, 2010; Alves et al , 2012; Bellon et al , 2012; Streito et al ., 2012). However, misidentifications are frequent because of the intraspecific variability within the genus (Froeschner, 1993), so that the number of species involved could be different.…”

Cassava Varieties Trichome Density Influence the Infestation of Vatiga illudens (Hemiptera: Tingidae)

“…The IAPAR 19 and IAC 14 varieties, had an infestation which varied among the remaining varieties during the two seasons. Oliveira et al (2016), while evaluating the non-preference of V. illudens oviposition on cassava varieties, identified that IAC 90 and Santa Helena, were the varieties with a potential deterrent to the females' oviposition, whereas IAC 576-70 had a stimulating potential. These informations coincide with the largest and smallest infestations found in this study (Table 1).…”

Resistance of cassava genotypes to Vatiga manihotae (Drake 1922) (Hemiptera: Tingidae)

“…These insects when fed on MEcu 72 genotype have shown an increase in the development period, increase in the nymphal mortality rates and decrease of nymphal size and adults fecundity. To V. illudens the MEcu 72 genotype showed deterrence for oviposition, however, there are no studies about the biological parameters of lace bugs on this genotype (Oliveira et al, 2016). To improve the understanding about the bioecology and find new sources of resistance in cassava, the biological parameters and the demographics of V. manihotae on five cassava genotypes under controlled conditions were evaluated.…”