Search

The aim of this study was to identify resistance of tolerance type in Citrus and Poncirus genotypes towards the citrus leafminer (CLM), Phyllocnistis citrella. The quantitative variables leaf and shoot lengths, leaf width, number of larvae and new shoots, and fresh and dry shoots weights, and qualitative variables associated with foliar damage were evaluated in six Citrus-related genotypes infested with CLM. In preliminary trials with lime Rough lemon (C. jambhiri), the variables that best discriminated the infestation effect of CLM were established as the numbers of larvae and new shoots per plant together with the percentages of partially rolled leaves (PRL), rolled leaves (RL) and total damage (TD = RL + PRL). In subsequent tests with all six genotypes, the variables new shoots per plant, percentage of attacked but not rolled leaves (ANRL), RL and TD were found to be significant. Trifoliata Limeira (P. trifoliata) and hybrid C × R4 (C. sunki × P. trifoliata) presented the lowest percentages of RL and TD and the highest values of ANRL. A cluster analysis was performed considering all the variables analyzed and the most tolerant genotypes for CLM, namely hybridsC × R4, C × R315 (C. sunki × P. trifoliata), M × P222 [C. sinensis × Tangor Murcott (C. reticulata × C. sinensis)] and Trifoliata Limeira (P. trifoliata) were grouped apart from the less tolerant genotypes Sunki mandarin (C. sunki) and lime Rough lemon. In conclusion, genotypes Trifoliata Limeira and its hybrid C × R4 are the most tolerant to CLM.

Avaliou-se o comportamento de genótipos de feijoeiro sob a infestação de Bemisia tabaci (Genn.) biótipo B e Caliothrips phaseoli (Hood) em condições de campo, nas épocas de cultivo "de inverno", "das águas" e "da seca". Adotou-se o delineamento de blocos casualizados em esquema de parcelas sub-subdividida (19x3x6), com 19 genótipos (IAC Tybatã, IAC Una, FT Nobre, Pérola, Gen 96A98-15-3-32-1, Gen 96A45-3-51-52-1, IAC Alvorada, IAC Diplomata, Gen 96A3-P1-1-1, LP 98-122, LP 02-130, LP 01-38, LP 9979, BRS-Pontal, BRS-Requinte, BRS-Triunfo, BRS-Grafite, CV-48 e Z-28), três épocas de cultivos (inverno, águas e seca) e seis períodos de avaliação. As avaliações foram realizadas semanalmente, contando-se o número de ovos e ninfas de B. tabaci e ninfas de C. phaseoli em dez folíolos por parcela. Os genótipos IAC Una, Pérola, Gen 96A45-3-51-52-1, Gen 96A98-15-32-1, FT Nobre, IAC Tybatã, IAC Alvorada, LP 02-130, LP 01-38, LP 98-122, IAC Diplomata e Gen 96A3P1-1-1 foram menos ovipositados por B. tabaci no cultivo "das águas". Os genótipos Pérola, Gen 96A45-3-51-52-1, IAC Una, Gen 96A98-15-32-1, IAC Tybatã e FT Nobre foram menos infestados por C. phaseoli. A maior incidência de ninfas de mosca-branca ocorreu no fim de janeiro no cultivo "das águas" e início de maio no cultivo "da seca"; para tripés, foi em junho durante o cultivo "de inverno". A maior incidência da população de B. tabaci e C. phaseoli, ocorreu dos 46 aos 60 dias após a emergência das plantas.The response of bean genotypes to infestation of Bemisia tabaci (Genn.) biotype B and Caliothrips phaseoli (Hood) in field conditions on the winter, rainy and dry seasons was evaluated. The experiment was arranged in a randomized Sub-divided (19x3x6) blocks design with 19 genotypes (IAC Tybatã, IAC Una, FT Nobre, Pérola, Gen 96A98-15-3-32-1, Gen 96A45-3-51-52-1, IAC Alvorada, IAC Diplomata, Gen 96A3-P1-1-1, LP 98-122, LP 02-130, LP 01-38, LP 9979, BRS-Pontal, BRS-Requinte, BRS-Triunfo, BRS-Grafite, CV-48 and Z-28) Three crops seasons of (winter, rainy and dry seasons) and six periods of evaluations were considered. The evaluations consisted on counting eggs and nymphs of B. tabaci biotype B and nymphs of C. phaseoli in 10 leaflets per plot. The genotypes IAC Una, Pérola, Gen 96A45-3-51-52-1, Gen 96A98-15-32-1, FT Nobre, IAC Tybatã, IAC Alvorada, LP 02-130, LP 01-38, LP 98-122, IAC Diplomata e Gen 96A3P1-1-1 were the least oviposited by B. tabaci biotype B, in rainy season. The least presence of C. phaesoli was observed on Gen 96A45-3-51-52-1, IAC Una, Gen 96A98-15-32-1, IAC Tybatã and FT Nobre. The highest occurrence of whitefly nymphs was observed during rainy season and beginning of the dry season, while the thrips preferred the winter season. The highest incidence of the population of B. tabaci biotype B and C. phaseoli, was found 46 to 60 DAE.