title: A new concept for insect damage evaluation based on plant physiological variables.
abstract: The objective of this study was to determine the damage levels caused by Orthezia praelonga Douglas, 1891 and Leucoptera coffeella (Guérin-Mèneville 1842), on rangpur lime and Obatã coffee leaves, respectively. Measurements were based on a new concept for the evaluation of the following plant physiological parameters: photosynthesis, stomatal conductance, leaf temperature and transpiration, and internal concentration of CO2 (by infrared analyzer). A negative correlation between infestation level and photosynthesis was found, where the negative inflexion point of the curve was considered as a reference for damage levels. The control level for O. praelonga is below the 7-13% limit for damaged leaf area (40 to 70 scales per leaf), while for L. coffeella it is below the 26-36% limit for the same variable. Photosynthesis provided the best correlation for this type of analysis.
authors.affiliation: Laboratório de Biologia de Insetos, Departamento de Entomologia, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, SP, Brazil.
authors.forename: Ademir D
authors.initials: AD
authors.lastname: Neves
authors.forename: Ricardo F
authors.initials: RF
authors.lastname: Oliveira
authors.forename: José R P
authors.initials: JR
authors.lastname: Parra
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism; D002957:Citrus / Q000469:parasitology*; D003069:Coffee / Q000469:parasitology*; D005260:Female; D007915:Lepidoptera; D008297:Male; D010788:Photosynthesis / Q000502:physiology*; D010935:Plant Diseases / Q000469:parasitology*; D018515:Plant Leaves / Q000469:parasitology; D018526:Plant Transpiration / Q000502:physiology*; D013696:Temperature; D013997:Time Factors
chemical_list: D003069:Coffee; D002245:Carbon Dioxide