RESUMO O uso de cultivares de alface resistentes é uma das formas de controle do míldio. Objetivou-se avaliar as resistências vertical e horizontal de progênies F5:6 de alface biofortificada com carotenoides aos fenótipos de virulência de Bremia lactucae: 63/63/51/00, 63/31/19/00 e 63/63/19/00. O delineamento experimental utilizado foi inteiramente casualizado, em parcelas subdivididas no tempo. Nas parcelas utilizaram-se os 12 genótipos de alface e nas subparcelas utilizou-se o tempo, sendo este de 7 a 18 dias após a inoculação. Para cada fenótipo de virulência de Bremia lactucae fez-se um experimento separado, com três repetições. Para selecionar genótipos resistentes procedeu-se a inoculação, com mistura de água destilada, esporângios retirados de tecidos infectados do hospedeiro e Tween 20. A avaliação dos genótipos iniciou-se quando houve o aparecimento da esporulação nas folhas cotiledonares da cultivar suscetível Solaris, verificando-se a proporção de plantas necrosadas e com esporulação. Houve interação entre genótipos e tempos para todos os fenótipos de virulência avaliados. Os genótipos de alface biofortificada UFU-189#2, UFU-206#1, UFU-215#3 e UFU-215#14 apresentam resistência vertical aos fenótipos de virulência 63/63/51/00, 63/31/19/00 e 63/63/19/00 de B. lactucae. Níveis de resistência horizontal foram observadas no genótipo UFU- 206#1 para os fenótipos de virulência 63/63/51/00 e 63/31/19/00; no genótipo UFU-66#7 para o fenótipo de virulência 63/31/19/00 e no genótipo UFU-215#10 para o fenótipo de virulência 63/63/19/00 de Bremia lactucae.

ABSTRACT The use of resistant cultivars is one of the strategies for downy mildew management. The objective of this study was to evaluate the vertical and horizontal resistance of F5:6 progenies of carotenoidbiofortified lettuce to virulence phenotypes of Bremia lactucae 63/63/51/00, 63/31/19/00 and 63/63/19/00. The experimental design was completely randomized and subdivided into plots that were evaluated over time. In the plots, 12 genotypes of lettuce were used, and the subplots were monitored over time (7th to the 18th day after inoculation). For each virulence phenotypes of Bremia lactucae, a separate experiment was performed with three replicates. To select resistant genotypes, plants were inoculated with distilled water, sporangia removed from infected tissues and Tween 20. The genotypes were evaluated when sporulation appeared on cotyledonary leaves of the susceptible cultivar Solaris, verifying the proportion of necrotic and sporulated plants. There was a correlation between genotypes and times for all virulence phenotypes evaluated. Genotypes UFU-189#2, UFU-206#1, UFU-215#3 and UFU-215#14 showed vertical resistance to virulence phenotypes 63/63/51/00, 63/31/19/00, and 63/63/19/00 of B. lactucae. Horizontal resistance levels were observed in genotype UFU 206#1 for virulence phenotypes 63/63/51/00 and 63/31/19/00; in genotype UFU-66#7 for virulent phenotype 63/31/19/00; and in genotype UFU-215#10 for virulence phenotype 63/63/19/00.

ABSTRACT Coffee production faces challenges due to the susceptibility of the crop to insects. Owing to the coffee leaf miner Leucoptera coffeella, which is one of the main insect pests, the technology for the application of phytosanitary measures becomes the main challenge for coffee growers. This study aimed to evaluate the effectiveness of coffee leaf miner control using different methods of application. The study was conducted in an experimental site in the municipality of Monte Carmelo - Minas Gerais. Spray depositions in different positions of the plant canopy and the effective control of coffee leaf miner were evaluated using the following application treatments: a hydropneumatic sprayer with varying spray volumes (200 and 400 L ha-1), two hollow-cone spray nozzles with the presence and absence of agricultural adjuvant, and electrostatic application using a spray volume of 200 L ha-1 with and without spray adjuvant. The addition of an adjuvant to the spray did not influence coffee leaf miner control; in contrast, a spray volume of 200 L ha-1 combined with the application of coarse droplets was efficient in the management of insect pest. The reduction in the rate of the application using coarse droplets increased the operational capacity and reduced spray drift potential.

RESUMO Condições meteorológicas adversas, ou problemas mecânicos e redução na taxa de aplicação, podem aumentar o tempo de armazenamento da calda no tanque do pulverizador. Objetivou-se avaliar o efeito do armazenamento da calda fitossanitária na germinação de conídios de Beauveria bassiana, com e sem adjuvantes. Utilizou-se delineamento experimental inteiramente casualizado, em esquema fatorial 13 x 5, composto por treze períodos de armazenamento (0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44 e 48 h) e cinco composições para a calda de pulverização (B. bassiana, B. bassiana + Helper Neutrum, B. bassiana + TA-35, B. bassiana + Nimbus e B. bassiana + Orobor). A calda biológica contendo conídios de B. bassiana sem adjuvantes manteve-se viável para uso após seu preparo e a germinação dos conídios reduziu-se 9,2 vezes após 48 h com a adição de adjuvante.

ABSTRACT Adverse weather conditions, or mechanical problems and decrease in the application rate, may increase the storage time of the spray solution in the sprayer tank. This study aimed to assess the effect of the phytosanitary spray solution storage on the germination of Beauveria bassiana conidia, with or without agricultural adjuvants. A completely randomized design was used, in a 13 x 5 factorial scheme, consisting of thirteen storage times (0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44 and 48 h) and five compositions for the spray solution (B. bassiana, B. bassiana + Helper Neutrum, B. bassiana + TA-35, B. bassiana + Nimbus and B. bassiana + Orobor). The biological spray solution containing B. bassiana conidia and no adjuvants remained viable for use after preparation and the conidial germination decreased 9.2 times after 48 h when an adjuvant was added.