The objective of this study was to characterize the diversity of mites on coffee plants of the Mundo Novo cultivar in two important coffee producing areas (Jeriquara and Garça) in the state of São Paulo. Samples of leaves, branches and fruits were fortnightly collected, from April 2001 to June 2003, from the middle third of 10 plants randomly taken from each field. Twelve leaves (each leaf from the third or forth pair from the distal part of each branch), 12 branches (apical 25 cm) and 100 fruits. A total of 13,052 specimens were collected in the two studied places, 7,155 in Jeriquara and 5,897 in Garça. From a total of 108 mite species collected from coffee plants in this study, forty five species were collected in both studied fields, which presented 56% of similarity. The number of species found exclusively in Jeriquara (47) was approximately three times higher than the number of species observed only in Garça (16). For Jeriquara, the diversity of mites on surface of leaves, as well as in domatia, and on branches and fruits was higher than for Garça. In both studied areas, Brevipalpus phoenicis (Geijskes, 1939) and Oligonychus ilicis (McGregor 1919) were the most abundant and frequent phytophagous mite species. Stigmaeids and phytoseiids were the most abundant and frequent predaceous mites in both localities.

IntroduçãoO arroz está entre os mais importantes cereais cultivados e apresenta grande importância social (PEREIRA, 1996). Está presente nos países em desenvolvimento e é considerado um dos alimentos com melhor balanceamento nutricional, pois fornece 20% da energia e 15% da proteína "per capita" necessárias ao homem. O arroz é uma cultura extremamente versátil, que se adapta a diferentes condições de solo e clima, e é considerada a espécie de maior potencial de aumento de produção no combate à fome do mundo (GOMES; MAGALHÃES JÚNIOR, 2004).Mas, quando o arroz é armazenado, sofre danos pelas mais diversas causas, tais como temperatura, umidade, ataque de roedores, microrganismos e insetos, sendo os insetos os prin- AbstractThe objective of this research was to verify the viability of the gamma radiation as polished rice (Oryza sativa L.) conservation method. The samples were irradiated with doses of 0.5; 1.0; 3.0; and 5.0 kGy. Analysis of the grain breakage during the enriching process, longevity and reproduction of the Sitophilus oryzae L., centesimal composition, apparent amylose content, starch paste properties, color (instrumental), and the sensorial evaluation of raw and cooked rice were performed. It was verified that the irradiation did not change the percentage of grain breakage during the enrichment process, and it caused a negative effect on the development of insects. The irradiation did not change significantly the centesimal composition and the apparent amylase content. The Tukey test (p ≤ 0.05) was conducted to verify the differences between the treatments. Gamma irradiation affected the pasting properties of the rice flour. Pasting parameters as temperature, peak, final viscosity, and setback values showed decreasing values with irradiation doses. Differences were detected in the sensorial aspect among the samples, and the sample irradiated with the dose of 1.0 kGy presented greater averages. Regarding the instrumental color parameter, it was observed the difference in the values b* indicating that the rice changed the white color for yellowish with the increase in the irradiation dose. The irradiation dose of 1.0 kGy proved the best to meet the objectives of this study. Keywords: rice; irradiation; sensorial; starch; Sitophilus oryzae L. ResumoA pesquisa teve como objetivo verificar a viabilidade da radiação gama como método de conservação do arroz polido (Oryza sativa L.). As amostras foram irradiadas com doses 0,5; 1,0; 3,0; e 5,0 kGy. Foram realizadas análises da quebra do grão no beneficiamento, da longevidade e reprodução do Sitophilus oryzae L., a composição centesimal, o conteúdo de amilose aparente e propriedades de pasta dos amidos, e análises para cor (instrumental) e análise sensorial do arroz cru e cozido. Foi utilizado teste de Tukey (p ≤ 0,05) para verificar a diferença estatística entre os tratamentos. A irradiação não alterou a porcentagem de quebra dos grãos durante o beneficiamento e causou efeito negativo no desenvolvimento dos insetos. A irradiação não alterou de maneira signifi...

Light-based methods are being further developed to meet the growing demands for food in the agricultural industry. Optical imaging is a rapid, non-destructive, and accurate technology that can produce consistent measurements of product quality compared to conventional techniques. In this research, a novel approach for seed quality prediction is presented. In the proposed approach two advanced optical imaging techniques based on chlorophyll fluorescence and chemometric-based multispectral imaging were employed. The chemometrics encompassed principal component analysis (PCA) and quadratic discrimination analysis (QDA). Among plants that are relevant as both crops and scientific models, tomato, and carrot were selected for the experiment. We compared the optical imaging techniques to the traditional analytical methods used for quality characterization of commercial seedlots. Results showed that chlorophyll fluorescence-based technology is feasible to discriminate cultivars and to identify seedlots with lower physiological potential. The exploratory analysis of multispectral imaging data using a non-supervised approach (two-component PCA) allowed the characterization of differences between carrot cultivars, but not for tomato cultivars. A Random Forest (RF) classifier based on Gini importance was applied to multispectral data and it revealed the most meaningful bandwidths from 19 wavelengths for seed quality characterization. In order to validate the RF model, we selected the five most important wavelengths to be applied in a QDA-based model, and the model reached high accuracy to classify lots with high-and low-vigor seeds, with a correct classification from 86 to 95% in tomato and from 88 to 97% in carrot for validation set. Further analysis showed that low quality seeds resulted in seedlings with altered photosynthetic capacity and chlorophyll content. In conclusion, both chlorophyll fluorescence and chemometrics-based multispectral imaging can be applied as reliable proxies of the physiological potential in tomato and carrot seeds. From the practical point of view, such techniques/methodologies can be potentially used for screening low quality seeds in food and agricultural industries.

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