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The effect of aromatic plants on number of twospotted spider mite (TSSM), Tetranychus urticae Koch, when intercropped with strawberry were assessed in the field. During the first year, chives (Allium schoenoprasum L.), coriander (Coriandrum sativum L.), fennel (Foeniculum vulgare Mill.), garlic (Allium sativum L.), oregano (Origanum vulgare L.), or sweet marjoram (Origanum majorana L.) were intercropped with strawberry. Assessments were performed on TSSM populations by taking six samples from July 20 to September 20, 2012. During the second year, garlic plants were intercropped between rows of strawberry at three densities in greenhouse and field. Mobile forms and eggs numbers (only in field) of TSSM were evaluated from April 18 to June 05 (greenhouse) and June 06 to August 14, 2013 (field). It was found that intercropping with garlic caused a greater reduction of TSSM (up to 52 %) in strawberry plants when higher populations of TSSM occurred in the field. TSSM reduction was found in one sample when fennel and chives were intercropped with strawberries (42 and 50 % reduction, respectively); this also occurred when populations of TSSM were higher. The three densities of garlic plants (one, two and three rows among the strawberry rows) reduced TSSM mobile forms by 49, 53 and 60 % (greenhouse) and 44, 51 and 65 % (field), and eggs by 38, 43 and 64 % (field), respectively. The results suggest that intercropping garlic plants between strawberry rows is a promising strategy to reduce TSSM populations.

-Ten popcorn inbred lines were crossed in a circulant partial diallel matching scheme (group of lines derived from IAC 112 × group of lines from 'Zaeli'). The hybrids were evaluated in respect to grain yield (GY), popping expansion (PE), and resistance to southern rust (Puccinia polysora, Pp), in randomized block design, with three replications. Data was examined by analyses of variance and Kempthorne and Curnow's diallel analysis. General combining ability (GCA) was significant (p < 0.10) in the set 2-Zaeli for GY, PE, and partial resistance to Pp. This indicated that additive gene effects are predominant, and therefore breeding methods of recurrent selection are recommended. However, none of lines had outstanding GCA for GY and PE. The line P 8.5 was recommended to form breeding populations for resistance to Pp. Specific combining ability (SCA) was detected for GY. The P 9.24 × P 8.6 might be promising for GY, if exploited using interpopulational breeding methods.Key words -Zea mays. General and specific combining ability. Puccinia polysora. Plant breeding.Resumo -Dez linhagens de milho-pipoca (grupo de linhagens IAC 112 × grupo de linhagens 'Zaeli') foram cruzadas em esquema dialélico parcial circulante. Os híbridos foram avaliados quanto ao rendimento de grãos (RG), capacidade de expansão (CE) e resistência parcial à ferrugem-polissora (Puccinia polysora Pp), em delineamento de blocos completos com tratamentos ao acaso, com três repetições. As características foram utilizadas para análises de variância e dialélicas de Kempthorne e Curnow. A capacidade geral de combinação (CGC) foi significante (p < 0,10) no grupo Zaeli para RG, CE e resistência à Pp. Isto indicou a predominância de genes aditivos, e que métodos de seleção recorrente são recomendados para estas características. Não foram encontradas linhagens com CGC favoráveis para RG e CE. A linhagem P 8.5 foi recomendada para integrar populações para melhoramento visando resistência à Pp. A capacidade específica de combinação somente foi detectada para RG. O híbrido P 9.24 × P 8.6 pode ser promissor para RG se explorando usando métodos intrapopulacionais de melhoramento. Palavras-chave -Zea mays.Capacidades geral e específica de combinação. Puccinia polysora. Melhoramento vegetal.

Para avaliar a resistência de híbridos experimentais e comerciais de milho-pipoca à Exserohilum turcicum, agente causal da helmintosporiose do milho, implementou-se um ensaio em delineamento de blocos completos com tratamentos ao acaso, com quatro repetições, em Maringá, Paraná, na safra 2007/2008. O objetivo adicional foi comparar a eficiência de discriminação da resistência utilizando apenas uma das avaliações ou uma série de avaliações. Incidência e a severidade, avaliadas em quatro avaliações, foram usadas para estimar a área abaixo da curva de progresso da incidência (AACPI) e da severidade (AACPS). Os dados de incidência e severidade na última avaliação, mais a AACPI e AACPS foram submetidos à análise de variância e teste de Scott-Knott para comparar a resistência dos genótipos. A análise de correlações de postos de Spearman foi utilizada para verificar qual o grau de associação entre os dados de severidade, de incidência, AACPS e AACPI. Foram constatadas diferenças significativas (P≤0,001) de resistência entre os genótipos avaliados, permitindo a formação de três agrupamentos de resistência. Os híbridos UEM129, UEM145, UEM140, UEM116 e UEM101 apresentaram menores índices de intensidade da doença, e foram considerados os genótipos mais resistentes. Estes híbridos superaram os híbridos UEM109, UEM153 e IAC 112, classificados como resistentes, e Zélia e Jade, considerados susceptíveis. Pelas correlações constatou-se que a avaliação de incidência e severidade no estádio de grão pastoso não proporcionou dados equivalentes à AACPS e AACPI para a discriminação da resistência à E. turcicum.

Strawberry is affected by several pests and diseases. Neopamera bilobata is an emerging pest that has been reported by several strawberry growers, usually associated with catfacing symptoms in fruits. We evaluated intercropping garlic or Chinese chives on N. bilobata populations on strawberry crops grown in high tunnels in two experiments. In the first experiment, we evaluated N. bilobata populations on strawberry intercropping with garlic plants (three densities: 8, 16, 24 GP - garlic plant per plot) on the bags by taking 12 samples from December 2015 to April 2017. N. bilobata populations on strawberry were also assessed when Chinese chives were grown under the suspended wooden structures in which strawberry plants are grown ('undercropping') (14 samples), in two high tunnels, from November 2016 to March 2017. The number of nymphs and adults on 14 randomly selected fruits per plot were assessed. During the garlic intercropping experiment, the treatments of three densities of garlic reduced N. bilobata populations; however, the 24 GP treatment caused a greater reduction than the 8 GP treatment. Garlic densities reduced N. bilobata populations by 35, 50, and 64% for the 8, 16, and 24 GP treatments, respectively. Chinese chives cultivated under the structures reduced N. bilobata populations by 47%. The results suggest that intercropping garlic or undercropping Chinese chives are suitable tools to be tested in integrated pest management in strawberry crops.

The red palm mite (RPM), Raoiella indica (Hirst) (Acari: Tenuipalpidae), was found for the first time in the Paraná State, in southern Brazil. The first observations occurred in September 2015, on strawberry (Fragaria × ananassa Duch) leaves, which is not considered a typical host plant of RPM. It is probable that its occurrence on this plant was serendipitous. Visual surveys for RPM were carried out on four typical host plants (banana, coconut, foxtail palm, and real palm), in five cities of the Paraná State (Bela Vista do Paraíso, Londrina, Maringá, Marialva, and Sarandi). RPM was found on each of the four typical host plants, in each of the five cities. Our survey extends RPM occurrence to the southern region of Brazil and indicates that the pest could be widespread in the country.

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-The level of genetic resistance to foliar diseases in 54 new