Relations between zero-inflated variables in trials with horticultural crops

Certain characteristics of some vegetable crops allow multiple harvests during the production cycle; however, to our knowledge, no study has described the behavior of fruit production with progression of the production cycle in vegetable crops with multiple harvests that present data overdispersion. We aimed to characterize the data overdispersion of zero-inflated variables and identify the behavior of these variables during the production cycle of several vegetable crops with multiple harvests. Data from 11 uniformity trials were used without applying treatments; these comprise the database from the Experimental Plants Group at the Federal University of Santa Maria, Brazil. The trials were conducted using four horticultural species grown during different cultivation seasons, cultivation environments, and experimental structures. Although at each harvest, a larger number of basic units with harvest fruit was observed than units without harvest fruit, the basic unit percentage without fruit was high, generating an overdispersion within each individual harvest. The variability within each harvest was high and increased with the evolution of the production cycle of Capsicum annuum, Solanum lycopersicum var. cerasiforme, Phaseolus vulgaris, and Cucurbita pepo species. However, the correlation coefficient between the mean weight and number of harvest fruits tended to remain constant during the crop production cycle. These behaviors show that harvest management should be done individually, at each harvest, such that data overdispersion is reduced.

Adubação nitrogenada em cobertura no feijoeiro em sucessão ao milheto solteiro e consorciado com guandu-anão.

Considerando que elevadas quantidades de nitrogênio (N) são requeridas pelo feijoeiro em sucessão a resíduos culturais de gramíneas solteiras e/ou consorciadas com leguminosas, objetivou-se com esta pesquisa avaliar o desempenho agronômico do feijoeiro, cultivar Pérola, sob irrigação, em função de doses de N em cobertura, em sucessão aos cultivos de milheto solteiro e consorciado com guandu-anão. O delineamento experimental foi de blocos casualizados, com quatro repetições, em esquema de parcelas subdivididas. As duas parcelas foram constituídas pelo cultivo do feijoeiro em sucessão aos cultivos de milheto solteiro e consorciado com guandu-anão; e, nas subparcelas, foram aleatorizadas as doses de N (0, 60, 120 e 180 kg ha-1). Avaliou-se a produtividade de fitomassa seca das plantas de cobertura; no feijoeiro avaliou-se: número de vagens por planta, número de grãos por vagem, massa de 100 grãos e produtividade de grãos. O milheto solteiro e milheto consorciado com guandu-anão apresentaram produtividade de fitomassa seca semelhante. Apenas a produtividade de grãos foi afetada pelas culturas antecessoras, sendo superior na sucessão ao consórcio de milheto com guandu-anão. Em relação à adubação nitrogenada, a massa de 100 grãos e a produtividade de grãos aumentaram linearmente com as doses de N em cobertura. A dose de 180 kg ha-1 de N não foi suficiente para promover a máxima expressão do potencial para massa de 100 grãos e produtividade do feijoeiro.

Estudos bioecológicos da mosca mineira Liriomyza (diptera: agromyzidae) e dos seus parasitóides, em culturas protegidas, no Algarve

Tese de dout. em Ciências Agrárias, especialidade Protecção de Plantas, Faculdade de Engenharia e Recursos Naturais, Univ. do Algarve, 2001

Drought impact on rainfed common bean production areas in Brazil.

Common bean production in Goiás, Brazil is concentrated in the same geographic area, but spread acrossthree distinct growing seasons, namely, wet, dry and winter. In the wet and dry seasons, common beansare grown under rainfed conditions, whereas the winter sowing is fully irrigated. The conventional breed-ing program performs all varietal selection stages solely in the winter season, with rainfed environmentsbeing incorporated in the breeding scheme only through the multi environment trials (METs) wherebasically only yield is recorded. As yield is the result of many interacting processes, it is challengingto determine the events (abiotic or biotic) associated with yield reduction in the rainfed environments(wet and dry seasons). To improve our understanding of rainfed dry bean production so as to produceinformation that can assist breeders in their efforts to develop stress-tolerant, high-yielding germplasm,we characterized environments by integrating weather, soil, crop and management factors using cropsimulation models. Crop simulations based on two commonly grown cultivars (Pérola and BRS Radi-ante) and statistical analyses of simulated yield suggest that both rainfed seasons, wet and dry, can bedivided in two groups of environments: highly favorable environment and favorable environment. Forthe wet and dry seasons, the highly favorable environment represents 44% and 58% of production area,respectively. Across all rainfed environment groups, terminal and/or reproductive drought stress occursin roughly one fourth of the seasons (23.9% for Pérola and 24.7% for Radiante), with drought being mostlimiting in the favorable environment group in the dry TPE. Based on our results, we argue that eventhough drought-tailoring might not be warranted, the common bean breeding program should adapttheir selection practices to the range of stresses occurring in the rainfed TPEs to select genotypes moresuitable for these environments.

A review of maize-beans and maize-cowpea intercrop systems in the semiarid Northeast Brazil.

Fifty-one experiments on maize -beans and 34 on maize-cowpea intercropping systems conducted mostly in semiarid Northeast Brazil were analysed to get an understanding of the performance of these intercrops in terms of their productivity as well as stability. Both the intercrop systems produced higher yields over their respective sole crops under a wide range of agroclimates; the average advantage with maize-beans was 32%, while that from maize-cowpea was 41%. The optimum row proportion for maize-beans was one maize: three beans, requiring 59% of sole crop maize population and 75% sole bean population. In maize-cowpea, alternate rows or one maize: two cowpea arrangement with about 50% of sole maize density and 100% of sole cowpea population seemed to be optimum. The intercrops failed less frequently compared to sole crops to meet specified incomes or yields. Sorghum seemed to be a good alternative to the traditional cereal because of its improved and consistent performance. Future research needs are discussed for further yield improvement in these two intercrop system.s

Caracterização e avaliação agronômica de novos isolados de rizóbio obtidos de nódulos de genótipos silvestes de feijoeiro-comum.

Este trabalho teve como objetivos avaliar a capacidade de utilização de fontes de C, tolerância à salinidade e temperatura, caracterizar genotipicamente e determinar a eficiência agronômica de novos isolados de rizóbio em condições de campo.

Major loci controlling resistance to the angular leaf spot of common bean.

Based on the evidences presented in this paper, results from classical genetic studies, fine-mapping information and physical position analysis using the reference genome sequence of P. vulgaris, the BIC Genetic Committee has formally accepted the proposed new gene symbols.

Resistance to Fusarium wilt in common bean cultivars and lines in pre-commercial stage.

The objective of this study was to identify common bean cultivars with resistance to Fusarium wilt.

Phenotypic and molecular characterization of common bean genotypes for resistance to anthracnose.

This study aimed to perform phenotypic and molecular characterization of cultivars and breeding lines of common bean for resistance to anthracnose.

Cooking time of common bean: genetic parameters and selection of elite lines.

The objectives of this study were to investigate the genetic variability and select elite lines for CT, since these lines aggregate essential agronomic traits.

Progeny tests for common bean isolines resistant to diseases with the aid molecular markers.

The aim of this study was progeny tests in segregating populations for resistance genes to these three diseases.

Pyramided lines of "carioca" common bean and their reaction to Pseudocercospora griseola.

The present work aimed to characterize lines produced by the Breeding Program of Common Bean (PMGF) of the Federal University of Viçosa (UFV), called ?Ruda R3? and ?Pérola R1?, in reaction to different races of P. griseola.

Marker-assisted selection integrated to the embrapa common bean breeding program.

The establishment of a specific Marker-Assisted Selection Facility at the Embrapa Rice and Beans Biotechnology Laboratory, in 2014, has better supported the routine analysis with molecular markers demanded by the Embrapa Common Bean Breeding Program. In addition, it has also supported other Embrapa plant breeding programs, such as rice and cotton.

Productivity, adaptability and stability of production of special grain common bean lines in different environments of Minas Gerais, Brazil.

This study aimed to select special grain bean lines with high productivity, adaptability and stability of production, evaluated in different environments of the Minas Gerais State, Brazil.

Identification of common bean resistant sources to angular leaf spot disease in a brazilian germplasm collection.

The aim of this study was to identify sources of resistance in the germplasm collection providing information of potential sources of resistance to introduce in breeding programs.