NOTA
Mancha-arroxeada da nêspera e sua relação com os tripses das flores, o percevejo Sphictyrtus chryseis e o ácaro Eriophyes eriobotryae
Violet stain of loquat (Eriobotrya japonica) and its relation to flower thrips, the bug Sphictyrtus chryseis and the mite Eriophyes eriobotryae
M. Ojima*; C. J. Rossetto*; O. Rigitano
SUMMARY
The violet stain of loquat fruits is an important problem of this crop in the State of São Paulo, Brazil. The elimination of two species of flower thrips, Frankliniella difficilis Hood, 1925 and Haplothrlps gowdeyi (Franklin, 1908), with insecticide applications, did not affect the appearance of the fruits and the vegetative aspect of the plants, suggesting that these thrips are not noticeably noxious to the plants.
Adults of Sphictyrtus chryseis (Lichtenstein, 1797) (Hemiptera Coreidae) were confined on fruits. No relation between the infestation of this bug and violet stain was noticed. This species caused a typical damage to the fruits which could be of economic importance should the infestation be high and were the fruits not protected by paper bags as they normally are. In the place where the bug pierced the fruit a deformation sometimes ocurred and the pulp of the fruit became white and less juicy.
The control of the eriophyid mite Eriophyes eriobotryae Keifer, 1938, which is common in high numbers underneath the bracts, evidenced no difference in vegetative aspect and in percentage of stained fruits, between treated and untreated plants. The population of the mites practically disappeared when the fruits appeared. In December, when the plant was in the flowering period, the average number of mites per bract was 81.0, whereas in January when the plants were in the fruiting stage, this average was 4.2. This sudden fall in mite population was apparently due to intrinsic plant factors, for in January bracts of remaining flowers had the average 4.2, whereas bracts of small fruits had no mites. The changes in the physiology of the plant probably play an important role in the population dynamics of this mite.
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Recebida para publicação em 13 de novembro de 1975.
Datas de Publicação
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Publicação nesta coleção
11 Mar 2009 -
Data do Fascículo
1976