RESUMO Um dos principais serviços ecossistêmicos prestados à agricultura em todo o mundo é a redução de pragas por inimigos naturais. No entanto, a composição da paisagem afeta várias dimensões do controle de pragas, e o habitat não agrícola ao redor dos campos agrícolas mostra respostas variáveis entre diferentes regiões do globo. Nesse trabalho, danos por herbivoria e abundância de pragas foram comparados entre duas paisagens com distintas cobertura e uso do solo (1 - conservada, com alta complexidade estrutural; e 2- degradada, com baixa complexidade). As observações de campo foram realizadas em plantios experimentais de goiabeiras, no Cariri Paraibano, uma das regiões mais secas da Caatinga. Os resultados obtidos demonstram que danos provocados por insetos da ordem Orthoptera, especialmente gafanhotos, bem como sua abundância, foram significativamente menores na paisagem com de alta complexidade estrutural. Portanto, esses resultados apoiam a hipótese que danos às culturas e a abundância de pragas são menores em paisagens com alta complexidade estrutural. Além disso, os resultados são muito importantes para as regiões semiáridas, pois fornecem informações sobre a relação entre a estrutura da paisagem e os danos à cultura em uma lacuna regional. Como as regiões semiáridas são ecossistemas criticamente ameaçados em todo o continente americano, paisagens agrícolas sustentáveis com ações de restauração florestal podem ajudar essas regiões a alcançar o desenvolvimento sustentável.

ABSTRACT One of the major ecosystem services delivered to agriculture worldwide is the reduction of pests by natural enemies. However, the landscape composition affects multiple dimensions of pest control, and non-crop habitat surrounding farm fields shows variable responses across geographies. Here, crop damage and pest abundance were compared between local farms with two antagonistic land cover and land use aspects (1- High conservation, landscape with high structural complexity; 2- High degradation, landscapes with low complexity). The field data were collected at experimental guava orchards in the Cariri Paraibano, one of the driest regions in the Brazilian Caatinga. The results show that damage caused by orthopterans and their abundance was significantly smaller in the landscape with high structural complexity. Therefore, the results support the hypothesis that crop damage and pest abundance are smaller in landscapes with high structural complexity. Additionally, the results are very important for the dryland regions as they provide information about the relationship between landscape structure and crop damage plus pest abundance in a regional gap. As drylands are critically endangered in all American continents, sustainable agricultural landscapes with the application of natural cover restoration can help drylands to achieve sustainable development.

RESUMEN La soya tiene un gran valor comercial y todavía hay regiones sin indicaciones de genotipos tolerantes, como la región del Brejo Paraibano. El objetivo de este estudio fue analizar la adaptabilidad de 20 genotipos de soya seleccionados con grado de maduración relativo superior a 9. Los genótipos utilizados fueron: M8867RR, M8766RR, M9144RR, SYN1059 RR, MI-SOY 9350, ST 920 RR, TMG1175RR, M8372IPRO, M8527RR, M8644IPRO, TOPAZIO RR, UFV-16 (Capinópolis), UFVS: Berilo RR, 2013, 2012, 2010, 2005, QUARTZO, 2001 y 2008. El experimento fue conducido bajo diseño completamente al azar con cinco repeticiones. Los datos fueron sometidos a análisis de varianza y test de Tukey para comparación de medias. Por medio de la distancia generalizada de Mahalanobis fue posible aplicar las pruebas de Tocher y UPGMA. Además, con el método Singh y la correlación canónica evaluamos la cuantificación de las características que más contribuyeron a la divergencia genética. Sólo diez genotipos alcanzaron la madurez fisiológica de los cuales se evaluaron las siguientes características: longitud del hipocótilo, longitud y ancho de la hoja, altura de planta, diámetro de la flor, y longitud y ancho de la semilla. Las características del ancho de la hoja, diámetro de la flor y ancho de la semilla fueron significativas (P<0.05) y obtuvieron entre sí valores superiores a 1 para la relación entre el coeficiente de variación genética y el coeficiente de variación ambiental (CVG/ CVA). Los promedios más altos de las características significativas se observaron en los genotipos SYN1059 RR, UFVS: Berilo RR y 2013. Los genotipos SYN1059RR, M8766RR, M8867RR, UFVS: Berilo RR, 2012 y 2013 fueron seleccionados como los materiales parentales más apropiados para usar en programas de mejoramiento.

ABSTRACT Soybeans have great commercial value and there are still regions with no indications of promising genotypes, such as Brejo Paraibano region. The objective of this study was to analyze the adaptability of 20 soybean genotypes selected with a relative maturity degree above 9. The genotypes used were: M8867RR, M8766RR, M9144RR, SYN1059 RR, M-SOY 9350, ST 920 RR, TMG1175RR, M8372IPRO, M8527RR, M8644IPRO, TOPAZIO RR, UFV - 16 (Capinopolis) and UFVS: Berilo RR, 2013, 2012, 2010, 2005, QUARTZO, 2001, and 2008. A completely randomized experimental design was used with five replicates. The data were subjected to analysis of variance and Tukey test to compare the means. From the Mahalanobis generalized distance, it was possible to apply the Tocher and UPGMA tests. In addition, using the Singh method and canonical correlation, the quantification of the characteristics that contributed most to genetic divergence was evaluated. Only ten genotypes reached the physiological maturity, and the following variables were evaluated: hypocotyl length, leaf width and length, plant height, flower diameter, and seed width and length. The characteristics leaf width, flower diameter, and seed width were significant (P<0.05) and obtained values above 1 for the ratio between genotypic variation and environmental variation (CVG/CVE). The higher means for the significant characteristics were observed in the genotypes SYN1059 RR, UFVS: Berilo and 2013. The genotypes SYN1059 RR, M8766RR, M8867RR, UFVS: Berilo, 2012 and 2013 were selected as the most suitable parental material to use in breeding programs.

Abstract This study was conducted to identify the allelic interactions and genetic effects involved in genetic control of quantitative traits in Capsicum annuum. Six generations (P1, P2, F1, F2, BC1 and BC2) were used to study the variances, means and allelic interactions of 16 quantitative traits evaluated. The additive part of the phenotypic variance found for plant height, number of peppers per plant, days to flowering and days to fruiting lead to the conclusion that phenotypic selection in the F2 generation are likely effective in obtaining genetic gains. According to the reduced model, the traits of canopy width, fruit width and number of seeds per fruit were not influenced by epistatic effects, but only by additive and dominant effects, which allows selection of superior individuals in segregating generations or improvement of these traits by means of hybridization.