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O objetivo deste trabalho foi determinar a herança da resistência à murcha de Curtobacterium em feijoeiro. Foram realizados dois experimentos: no primeiro, cinco genótipos de feijoeiro, com diferentes reações de resistência à murcha de Curtobacterium, foram cruzados em arranjo dialélico; e no segundo, dois cruzamentos entre genótipos resistentes e suscetíveis - IAC Carioca Aruã x SCS Guará e IAC Carioca Pyatã x Pérola - foram realizados para dar origem às gerações P1, P2, F1, F2, RC1 e RC2. Em ambos os experimentos, a resistência do feijoeiro à murcha bacteriana foi avaliada por meio da inoculação do isolado Cff 2634. A análise dialélica mostrou que, embora efeitos aditivos e não aditivos estejam envolvidos, houve maior participação de genes com efeito aditivo no controle genético da resistência à murcha bacteriana, o que mostra a possibilidade de se obter sucesso com a seleção. A herança da resistência à murcha de Curtobacterium é complexa, com mais de três genes envolvidos, e herdabilidade no sentido restrito de 29%, para o cruzamento 'IAC Carioca Aruã' x 'SCS Guará', e de 44%, para o cruzamento 'IAC Carioca Pyatã' x 'Pérola'.

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The purpose of this study was to identify common bean genotypes resistant to bacterial wilt to be used as resistance sources in breeding programs targeting resistant cultivars. A total of 67 accessions, five cultivars and one control were evaluated, which were artificially inoculated with the Curtobacterium flaccumfaciens pv. flaccumfaciens isolate Cff 2634. The results prove the existence of alleles that confer tolerance to bacterial wilt in the cultivars IAC Carioca Aruã, IAC Carioca Pyatã and IAC Carioca Tybatã. The mean grades of disease symptoms were lowest in BAF 122 (Xan 159); this accession was identified as disease-tolerant and indicated for use in breeding programs to develop resistant cultivars.

Exposure of bulbs to cold, a physiological phenomenon called vernalization, and bulb size are important factors in the production of lily bulbs and flowers. This study aimed to verify the influence of vernalization of bulbs on flowering cut lily plants, as well as the impact of size and shape of harvest on the production and quality of flowers and bulbs. In turn, the way the stems of the plants used for cutflower production are cropped is of higher importance for the production of new flower bulbs. In this sense, the experiment was conducted in Viçosa, MG, in a greenhouse in a randomized block design, in split splot scheme with three replications, in which the vernalization periods (25, 35 and 45 days at 4 ± 1 C) constituted the plots; bulb sizes (diameters of 3.2-3.8 cm; 2.5-3.2 cm 1.9-and 2.5 cm), subplots and ways to harvest (full harvest of the stem at the required length for the commercial harvest of the flower, commercial stem harvest at the commercial length, maintaining 10cm of stem in the soil; removal of the floral buds as soon as their appearance is observed and harvest at the end of the season), the sub subplots. The bulbs were planted in beds, with 15 x 20 cm spacing. It was evaluated the number of plants that flowered and the number of flowers, the length and the diameter of the floral buds, fresh and dry weights, diameter and plant height as well as number, perimeter and amount of fresh and dry bulbs. There was a decrease in the plant height with the increase of the vernalization period and a reduction of the diameter of the planted bulbs, as well as of the number and the fresh and dry weights of the produced buds. The production of flowers and buds in number, size and weight was directly proportional to the size of the planted bulbs, while the form of harvest with removal of flower buds increased the number, the perimeter and the fresh and dry weights of the buds. Bulbs with diameter between 3.2 -3.8 cm, stored for 25 days in cold chamber enable greater production of flowers and the highest stem height, factors that favor the increase in market value. Key words: Exposure to cold. Flowering. Way of harvest. Lilium longiflorum. ResumoA exposição dos bulbos ao frio, fenômeno fisiológico denominado vernalização, e o tamanho do bulbo são importantes na produção de flores de lírio. Por sua vez, a forma de colheita das hastes das plantas utilizadas para corte de flor é preponderante na produção de bulbos filhos. Este estudo teve como objetivo verificar a influência da vernalização dos bulbos em plantas de lírio em flor, bem como o impacto do tamanho e forma da colheita na produção e qualidade de flores e bulbos. O experimento foi conduzido em Viçosa, MG em casa de vegetação, em blocos casualizados, com parcelas sub-subdivididas, com três repetições, em que os períodos de vernalização (25, 35 e 45 dias, a 4± 1̊ C) constituíram as parcelas; os tamanhos de bulbo (diâmetros de 3,2-3,8 cm; 2,5-3,2 cm e 1,9-2,5 cm), as subparcelas e as formas de colheita (colheita total da haste no ponto de colheita c...