Over a 5-year period (2006)(2007)(2008)(2009)(2010), 277 certified, visually healthy potato seed lots, imported from Europe to Israel for commercial use, were tested for Dickeya spp. latent infection by PCR analysis (277 seed lots) and ELISA (154 seed lots). Seeds from these lots were grown in commercial potato fields which were inspected twice a season by Plant Protection and Inspection Services (PPIS). Stem samples were tested for the presence of Dickeya spp. by PCR analysis. PCR and ELISA results from seed lot testing correlated with disease expression in 74 and 83AE8% of the cases, respectively. Positive laboratory results with no disease symptoms in the field ('+lab ⁄ )field' results) comprised 24AE7 and 9AE7% of the PCR and ELISA analyses, respectively, whereas negative laboratory results with disease symptoms in the field results (')lab ⁄ +field') were obtained in 1AE3 and 6AE5%, of cases respectively. Maximum disease incidence, as well as the number of cultivars expressing disease symptoms, increased over the years of this study, indicating an increase in the prevalence of the disease. Severe disease incidence was observed on cvs Dita, Rodeo, Desiree, Mondial, Tomensa and Jelly. Of the 55 imported seed lots from which disease was recorded in the field, 49 originated from the Netherlands, four from Germany and two from France. None originated from Scotland.

Huanglongbing (HLB) is a citrus disease of worldwide importance, associated with the presence of Candidatus Liberibacter asiaticus (Las) and vectored by the psyllid Diaphorina citri in Asia and the Americas. To properly manage HLB, removal of inoculum sources and control of the psyllid are undertaken. We evaluated the percentage of the psyllid population with Las, sampled from yellow sticky traps over a three-year period and its relationship with insect population, regions, season of the year, and HLB management in citrus areas in the southwestern, central, and northern regions of São Paulo (SP) and southwestern region of Minas Gerais states, Brazil. In each reading, up to 50 psyllids per region were collected and detection of Las in individual psyllids were made by quantitative polymerase chain reaction. The percentage of psyllids with Las—an average of 65.3%—was constant throughout the year in the southwestern region of SP state, while showing an increase from spring to autumn when sampled from central to northern regions. The proportion of psyllids carrying Las from each region and year period were compared by a proportion test and spectral density analysis. The proportion of psyllids carrying Las evaluated in the same region in different seasons presented statistical differences in central (Araraquara) and southwestern (Santa Cruz do Rio Pardo) regions in 2015, with higher values in the first semester (summer and autumn) than in the second semester (winter and spring). Orchards with poor HLB management had higher incidence of psyllids with Las. Spectral density analysis indicated that good management areas had 50% less relevant peaks of psyllids with Las than in areas with poor HLB management practices. The relationship between the percentage of psyllids carrying Las and the number of captured psyllids in the region in a given time denotes the most critical intake time for HLB spread in citrus orchards. The reduction in the population of psyllids carrying Las is a direct benefit from the use of good management practices.

In Western and Northern Europe, Dickeya species are causing increasingly severe economic losses in potato (Solanum tuberosum) crops. The costs of seed potato production resulting from Dickeya spp. infection are high due to rejection and declassification of seed tubers (Sławiak et al., 2009). Potato blackleg caused by Dickeya spp. is primarily a seed tuber-borne disease (Tsror et al., 2009). Symptoms including blackening of the stem base, wilting of plants and rotten seed tubers are observed. Recently, outbreaks of potato blackleg were recorded in Georgia on three cultivars, in Samtskhe-Javakheti region, Akhalkalaki district, in an area in excess of 100 hectares.

RESUMO -Objetivou-se com este trabalho estudar os efeitos do consórcio de milho com colonião (Panicum maximum cv. Aruana) na infestação de plantas daninhas e na cultura da soja em rotação. O experimento foi realizado em campo, no período de dezembro de 2008 a abril de 2010, em área experimental da UNESP, campus de Jaboticabal-SP. Utilizou-se o delineamento em blocos ao acaso, com quatro repetições, em esquema de parcela subdividida. Foram estudadas duas formas de semeadura (a lanço e em linha) de colonião nas parcelas e quatro quantidades de sementes (200, 400, 600 e 800 pontos de valor cultural -PVC) nas subparcelas, além de três testemunhas, representadas pelo monocultivo das espécies, como tratamentos adicionais. O cultivo consorciado não afetou o desenvolvimento do milho, comparado ao milho solteiro. Embora na colheita do milho houvesse maior matéria seca e densidade de plantas de colonião com a semeadura de 800 PVC, antes da semeadura da soja o acúmulo de massa não diferiu entre os tratamentos de consórcio. Portanto, a semeadura de 200 PVC de sementes de colonião, a lanço ou em linha, foi suficiente para a manutenção de quantidade (9,1 t ha -1 ) adequada de palha sobre o solo. Antecedendo a semeadura da soja, a infestação de plantas daninhas na testemunha de milho solteiro foi maior do que nos tratamentos de consórcio e nas testemunhas da forrageira solteira (a lanço e em linha). O mesmo foi observado para densidade de plantas daninhas após a instalação da cultura. Os sistemas de consórcio de milho com colonião não interferiram em nenhuma característica avaliada na cultura da soja cultivada em rotação. Da mesma forma, não foi observada diferença entre os tratamentos de consórcios e a testemunha de milho em monocultivo para produção de grãos de soja.Palavras-chave: Glycine max, integração agricultura-pecuária, plantio direto, Zea mays.ABSTRACT -This work aimed to study the effects of corn and colonião grass (Panicum maximum cv Aruana) intercropping on weed infestation and soybean crop in rotation. This research was carried out under field conditions from December 2008 to April 2010 at the UNESP Campus of Jaboticabal, São Paulo, Brazil. The experiment was arranged in a randomized block design in split-plots, with four replications. Two forms of sowing (hand-sowing and on-line sowing) of colonião grass and four amounts of seeds (200, 400, 600, and 800 points of cultural value -PCV) were studied, plus three additional treatments with the single species. Intercropping did not affect vegetative growth and corn yield, when compared to single corn. In the harvest of corn grains, there was more dry matter and plant density of colonião grass when 800 PCV were sown. However, before soybean sowing, dry matter production did not differ between the intercropping treatments. Thus, the sowing of 200 PCV of colonião seeds, hand-sowing and on-line sowing, was sufficient to maintain an adequate amount (9.1 ton ha -1 ) of mulch on the soil. Prior to soybean sowing, weed infestation in the single corn treatment was higher than ...

ResumoObjetivou-se estudar o consórcio de milho com amendoim forrageiro (Arachis pintoi cv. MG-100) e milho com calopogônio (Calopogonium muconoides), quanto ao desenvolvimento das plantas de milho, à produção de matéria seca pelas forrageiras, à infestação de plantas daninhas e o efeito desse sistema de produção na produtividade da soja em rotação. O experimento foi desenvolvido em campo, no período de dezembro de 2008 a abril de 2010, em área experimental da UNESP, Campus de Jaboticabal, SP. O delineamento experimental foi em blocos casualizados, com quatro repetições, em esquema de parcela subdividida 2 x 4 +1. Foram estudadas duas espécies forrageiras (amendoim forrageiro e calopogônio) semeadas nas parcelas, quatro quantidades de sementes (400, 800, 1200 e 1600 pontos de valor cultural ha -1 ) nas subparcelas e um tratamento adicional, representado pelo monocultivo do milho. O consórcio de milho com amendoim forrageiro e calopogônio não interferiu no desenvolvimento do milho em relação ao milho solteiro. O calopogônio teve maior densidade e matéria seca da parte aérea de plantas do que o amendoim forrageiro. O número de plantas e a matéria seca de calopogônio aumentaram linearmente com o aumento da quantidade de sementes semeada nas parcelas. Essas variáveis não foram influenciadas pela densidade de semeadura de amendoim forrageiro. A produção de palha pelas espécies forrageiras estudadas, antecedendo à cultura da soja em rotação, foi inexpressiva (menos de 1,1 toneladas por hectare). Os tratamentos de consórcio não afetaram a ocorrência de plantas daninhas e a produtividade da soja em rotação. Palavras-chave: Arachis pinto, Calopogonium muconoides, Glycine max, integração agriculturapecuária, plantio direto, Zea mays AbstractThis work aimed to study the intercropping of corn with Arachis pintoi cv. MG-100 and Calopogonium muconoides, regarding to vegetative growth and corn yield, capacity of production of forage dry matter, infestation of weeds and the effect of this system of production in the soybean crop in rotation. This research was carried out under field conditions form