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Guinea grass (Megathyrsus maximus)is widely used as a forage crop in Brazil, but its production faces disease threats. Recently, new symptoms, such as oblong to irregular brown lesions on leaves, have emerged in M. maximus across the country. Particularly severe symptoms were observed in the BRS Tamani cultivar, and some other genotypes showed lesion coalescence and intense leaf necrosis. This study aimed to identify the cause of these symptoms. A fungus was isolated from the lesions and, using morphological measurements and molecular analysis of the ITS, GPDH and TEF-1α genes, it was identified as Bipolaris yamadae. Pathogenicity tests confirmed its ability to cause disease in M. maximus cv. Tamani. A field survey of 205 M. maximus genotypes showed severe symptoms in 8.35 % of the materials.

ABSTRACT The objective of this study was to evaluate the influence of the environment and the genetic factor on the the phenology of 16 advanced selections of peachtrees in the municipality of Urussanga, state of Santa Catarina. The experiment was conducted in two areas (360 m and 220 m above sea level) in 2017, 2018, and 2019 harvests. The selections are part of the EPAGRI fruit breeding program. The dates of beginning, full, and end of flowering and budding, percentage of flowering, budding and effective fructification were determined. The standard model (number of hours with temperatures below 7.2 °C) was not the most suitable. Full flowering was anticipated by five days, on average over three years, at the highest altitude due to the greater accumulation of cold. The 16 selections were classified into three groups: early (harvest in October), medium (harvest in November), and late (harvest in December). It is concluded that the environment and the genetic factor influence the phenology of advanced peach selections. Being the first, it influences the periods of flowering and budding and the percentages of flowering, budding and effective fruiting. The second with emphasis the maturation cycle and the harvest period.

A produção de mudas de qualidade de maracujazeiro-azedo pode ser influenciada pelas características físico-químicas dos substratos utilizados. Objetivou-se avaliar as características físico-químicas de oito substratos comerciais e a influência no desenvolvimento de mudas de maracujazeiro-azedo em ambiente de cultivo protegido. O experimento foi conduzido no delineamento em blocos ao acaso com oito substratos comerciais, quatro repetições e seis mudas em vaso por parcela. Avaliaram-se altura das plantas, número de folhas, diâmetro do caule, massa seca da raiz e da parte aérea, pH e condutividade elétrica (CE) após 150 dias da semeadura. Para a maioria das variáveis físicas e químicas avaliadas, os substratos apresentaram indicativos ideais conforme as necessidades do sistema de cultivo. Os substratos TF F11, TF F e MP foram os que proporcionaram maior desenvolvimento às mudas devido à maior capacidade de retenção de água, maior acidez (entre 5 e 5,5) e densidade entre 230 e 340kg m-3.

Rootstocks of ‘Rangpur’ Lime and ‘Swingle’ Citrumelo were grown in containers with substrate in a greenhouse, aiming to evaluate the effects of N (urea) fertilization on the vegetative growth and macronutrient content of the plant tissue. The experimental design was a factorial randomized block design with four repetitions, and each experimental plot was composed of five plants. Four doses of N (0, 2.0, 4.0 and 8.0 g.plant-1) were evaluated and applied every week (15 applications) to both of the rootstocks. After 200 days of transplanting, the following parameters were evaluated: vegetative growth and total content of macronutrients on the dry weight of the leaves, stems, and roots. ‘Rangpur’ Lime was more vigorous that ‘Swingle’ Citrumelo. ‘Rangpur’ Lime showed the greatest accumulation of plant dry weight with 3.38 g.plant-1 of N and a greater root dry weight with 2.03 g.plant-1. For ‘Swingle’ Citrumelo, 2.03 g.plant-1 of N provided a greater plant dry weight, however, nitrogen fertilization reduced the root:canopy ratio of the rootstocks. The leaf content of N and P were favored by high doses of N in the tested range. Intermediate doses favored the Ca and Mg leaf contents. The leaf K content was decreased by nitrogen fertilization.

Abstract: The objective of this work was to evaluate the response of an in vitro host range to Spodoptera frugiperda multiple nucleopolyhedrovirus (SfMNPV), a pathogenic virus to the fall armyworm (Spodoptera frugiperda, Lepidoptera: Noctuidae), for the further development of a biopesticide based on cell culture systems. The cell lines from Bombyx mori (BM-5), Lymantria dispar (IPLB-LD-625Y), Trichoplusia ni (BTI-Tn-5B1-4), Anticarsia gemmatalis (UFL-AG-286), and S. frugiperda (IPLB-SF-21AE and Sf9) were tested for their susceptibility to a highly-virulent Brazilian isolate of SfMNPV. The cytopathic effects induced by the virus, the production of viral particles, and the synthesis of viral polypeptides were examined and compared. Both S. frugiperda cell lines showed hypertrophy of cell nuclei and production of many polyhedra. The SDS-Page of radiolabed proteins showed that the cell protein synthesis was shutoff, while an intense band of about 30 kDa, recognized as polyhedrin, was synthesized. The other cell lines did not show polyhedra production, although some of them underwent morphological changes and protein synthesis shutdown in response to virus infection. The SF-21 and Sf9 cell lines are recommended for further in vitro production of SfMNPV.

The use of arbuscular mycorrhizal fungi (AMF) in the production of rootstocks is an alternative to accelerate plant growth. However, their response depends on the symbionts species and environment. This study aimed at evaluating the influence of AMF species [Scutelospora heterogama, Gigaspora margarita, Glomus etunicatum, Acaulospora sp. and a control (non-inoculated)] on the vegetative development of citrus rootstocks {citrange 'Fepagro C37 Reck' [P. trifoliata (L.) Raf. x C. sinensis (L.) Osbeck.] and 'Kumquat' [Fortunella hindsii (L.) Swingle]}. The experimental design consisted of split-plot randomized blocks, with 10 plants per plot and 3 replications. Height, stem diameter, number of leaves, leaf area and fresh and dry root and shoot mass were evaluated. The colonization of AMF in the roots was also assessed, determining the percentage of colonization and density of hyphae, arbuscules and vesicles. The rootstocks showed no difference for the plant growth parameters, in the absence of AMF. The AMF species colonized the rootstocks roots, but were only effective in accelerating the citrange 'Fepagro C37 Reck' growth, especially when inoculated with Scutelospora heterogama, Gigaspora margarita and Glomus etunicatum. The influence of AMF on vegetative development depends on the citrus rootstock species.

A produção de mudas de maracujazeiro-azedo em ambiente protegido é uma tecnologia diferenciada, que qualifica o setor produtivo a reduzir ou até eliminar o risco de disseminação de doenças e pragas através das mudas. Também proporciona a obtenção de mudas avançadas (maiores que 80 cm de altura), que possibilitam antecipação de colheita e maior produtividade em áreas de ocorrência endêmica da virose do endurecimento dos frutos do maracujazeiro, principal doença dessa cultura.

The objective of this study was to define the input height to grazing and evaluate forage production of Italian ryegrass (Lolium multiflorum Lam.) cv. Barjumbo and cv. Common associated or not with oat black forage (Avena strigosa Schreb) cv. IAPAR 61, submitted to two post-grazing. Treatments consisted of a 4x2 factorial design, totaling eight treatments with three replications, being evaluated common and Barjumbo ryegrass, single and mixed with black oat in two highs of post-grazing residue: High: 50% of input height; Low: 30% of input height. Single Common ryegrass and combined with black oat obtained higher production than Barjumbo cultivate, and greater accumulation rate only when intercropped with black oat. Leaf blades production did not differ among cultivars. Stems production was low to Barjumbo cultivar. Black oat production was higher when associated with Barjumbo. Input height to Italian ryegrass cultivars with 95% light interception was 26.86 cm to Barjumbo and 28.75 cm to common cultivar, and when combined with black oat 34.01 cm and 32.48 cm, respectively.

Abstract: The objective of this work was to evaluate the phytosanitary aspect of two accessions of maize (Zea mays) seeds from the United States introduced to Brazil, regarding the presence of Wheat mosaic virus (WMoV). Two to three weeks after sowing, symptomatic leaves were tested by Elisa using specific antiserum to WMoV. The reaction was positive, and leaf samples were analyzed by real-time PCR and amplified PCR products were sequenced. The WMoV isolates had 99 to 100% nucleotide identity with isolates from Australia and the United States. Until now, there is no report of the presence of this virus in Brazil. According to the federal law on plant protection, the plants were burned to avoid the introduction of this exotic pest in the country. The obtained results show WMoV interception in Brazil.

Resumo: O objetivo deste trabalho foi avaliar as informações qualitativas e quantitativas sobre as interceptações de pragas ausentes não regulamentadas e quarentenárias em material vegetal importado. As informações sobre interceptações de pragas pelo serviço de quarentena vegetal da Embrapa, no período de 1977 a 2013, foram obtidas em um banco de dados, atas laboratoriais e listas de interceptação publicadas. As interceptações foram analisadas de acordo com regulamentação das pragas, espécie vegetal, parte vegetal importada e origem. O material foi categorizado em sementes botânicas e material de propagação vegetativa. No período do levantamento, foram interceptadas 75 espécies de pragas em 114 eventos de interceptação. Fungos, vírus e ácaros constituem a maior parte das interceptações, e a maioria delas ocorreu em lírio, oliveira, trigo, uva, arroz, batata e maçã. A taxa média anual de infestação/infecção do material vegetal analisado é de 2% dos processos de importação. O material para propagação vegetativa apresentou maior taxa de infestação/infecção por pragas do que as sementes botânicas. Das espécies-pragas interceptadas, 63% não são regulamentadas como quarentenárias para o Brasil. Esses resultados indicam a necessidade premente de revisão da atual lista de pragas quarentenárias do País.

ABSTRACT: Apple plants from France introduced in Brazil for research purposes were subjected to a phytosanitary analysis at the Plant Quarantine Laboratory of Embrapa Genetic Resources and Biotechnology (Cenargen). After grafting onto healthy apple rootstock, some plants showed phytoplasma-infection symptoms. Polymerase Chain Reaction (PCR) tests yielded DNA fragments of the expected size for phytoplasmas. DNA sequencing revealed an identity of the 16S rDNA nucleotide sequence of 98-99% with ‘Candidatus Phytoplasma solani’. This phytoplasma species is responsible for losses in European apple orchards and has not been reported in Brazil. According to the Federal Legislation on Plant Protection, the plants were incinerated to avoid the introduction of this exotic pest in Brazil.

The objective of this study was to evaluate carcass traits and meat quality of steers finished only on oat (Avena sativa L.) pasture or intercropped with vetch (Vica sativa) or associated with supplementation based grain ground corn. 18 steers, 1/4 Aberdeen Angus - ¼ Marchigiana - 2/4 Nellore with initial live weight and average age of approximately 360 kg and 19 months, respectively, were used. During 72 days the steers were kept in three different treatments: oat pasture, oat + legume pasture and oat pasture associated with supplementation based ground corn in the proportion of 1 % of body weight. After this period, the animals were slaughtered and the carcass traits and meat quality, were evaluated. The slaughter weight of steers receiving supplementation (428.5 kg) was higher than animals grazing only oats (400.67 kg), but did not differ of the slaughter weight of animals maintained on pasture oats and vetch (409.27 kg). The hot carcass weight (245.69 kg) and cold carcass weight (244.22 kg) of the animals receiving supplementation was higher than carcasses of animals grazing oat or oat + vetch. The carcass conformation of steers receiving supplementation (11.50 points) was higher than that animals grazing oat + vetch (10.17 points). There was no difference among treatments for metric measurements of carcasses. For commercial cuts, the hindecut + sidecut were heavier for animals receiving supplementation (158.20 kg). The meat from animals finished with oats showed less tenderness (6.53 points) when evaluated by the taste panel, requiring more shear force (6.32 kgf/cm2) .

The objective of this experiment was to evaluate the yield and quality of corn silage with different nitrogen levels. It was used four levels of nitrogen, 0, 80, 160, 240 kg.ha-1. The experimental design was randomized blocks with six replications. The data were subjected to analysis of variance and polynomial regression analysis. The silage was performed manually in PVC tubes of 10 cm diameter and 50 cm high. The parameters evaluated were productive variable, morphological variable, physiological efficiency, recovery efficiency and efficiency utilization of nitrogen, and nutritive value of silages. Plant height (height = 1.72+0.067*block+0.0004*N) and total production (total production = 13,883.42 + 786.41* block + 18.65*N) responded positively according increasing nitrogen dose. The decrease of recovery efficiency (NAR = 1.027-0.00283*N) and nitrogen use efficiency (NUE = 42.89 to 0.11 * N) with the increase in the amount of nitrogen applied. The crude protein of the silage shown a quadratic response (CP = 5.820+0.018*N-0.00005N2) according to the increase in nitrogen level. The increase in nitrogen levels provided better productivity with high quality silage. Higher doses showed lower nitrogen utilization efficiency and recovery nitrogen. O objetivo deste experimento foi avaliar a produção e a qualidade da silagem de milho com diferentes níveis de nitrogênio. Foram utilizados quatro níveis diferentes de nitrogênio, sendo: 0; 80; 160; 240 kg ha-1 de nitrogênio. O delineamento experimental utilizado foi o de blocos ao acaso com seis repetições. Os dados foram submetidos à análise de variância e à análise de regressão polinomial. A ensilagem foi realizada manualmente em tubos de PVC de 10 cm de diâmetro e 50 cm de altura. Foram avaliados os parâmetros produtivos, morfológicos, eficiências fisiológicas, de recuperação e de utilização do nitrogênio, além das variáveis bromatológicas das silagens. A altura da planta (Altura = 1,72 + 0,067*bloco + 0,0004*N) e produção total (Produção total = 13883,42+786,41*bloco+18,65*N) responderam positivamente ao incremento da dose de nitrogênio. Na medida em que houve incremento na quantidade de nitrogênio aplicado houve diminuição na eficiência de recuperação (RAN = 1,027 – 0,00283*N) e na eficiência de utilização do nitrogênio (EUN = 42,89 – 0,11*N). A proteína bruta da silagem apresentou resposta quadrática (PB = 5,820+0,018x-0,00005x2) de acordo com o aumento na dose de nitrogênio. O acréscimo nas doses de nitrogênio proporcionou melhor produtividade de silagem com alta qualidade. Maiores doses proporcionaram menor eficiência de utilização e de recuperação do nitrogênio.

O objetivo deste estudo foi avaliar o valor nutricional de dois cultivares de azevém (Lolium multiflorum Lam.) cv. Barjumbo e cv. comum, consorciados ou não com aveia preta (Avena strigosa Schreb) cv. IAPAR 61 submetidos a dois resíduos de forragem pós-pastejo. O trabalho foi realizado na Universidade Tecnológica Federal do Paraná, Câmpus Dois Vizinhos, no período de abril a setembro de 2012. Os tratamentos foram constituídos de um bifatorial 4x2, totalizando oito tratamentos com três repetições, sendo avaliados os azevéns comum e Barjumbo solteiros ou consorciados com aveia preta em duas alturas de resíduo pós-pastejo: Alto: 50% da altura de entrada; Baixo: 30% da altura de entrada. As variáveis avaliadas foram proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), nutrientes digestíveis totais (NDT) e digestibilidade in vitro da matéria seca (DIVMS). O Barjumbo solteiro apresentou maior PB. Os teores de FDN e FDA foram menores para o cultivar Barjumbo solteiro ou consorciado em relação ao cultivar comum e, como consequência, a DIVMS e NDT foram superiores. Dentro do período experimental, a pastagem apresentou ligeira elevação nos teores de PB, NDT e DIVMS até por volta de 100 dias após a emergência. Já os valores de FDN e FDA demonstraram uma elevação linear desde o início até o final do período de avaliações.

ABSTRACT The use of arbuscular mycorrhizal fungi (AMF) in the production of rootstocks is a strategy to promote faster plant growth. However, this response depends on the symbiont species. The objective of this study was to evaluate the influence of different species of arbuscular mycorrhizal fungus (AMF) on the development and physiology of citrange 'Fepagro C37 Reck' rootstock. Four species of AMF were used in the experiment: Scutellospora heterogama, Gigaspora margarita, Glomus etunicatum, and Acaulospora sp., and a control treatment. The experiment was arranged in a randomized blocks design, with 5 treatments, 3 replicates, and 10 plants per plot. Every 15 days, height (cm) and stem diameter (mm) of plants were measured in the nursery. At 330 days, the number of leaves, leaf area (cm²), fresh and dry mass of roots and shoot (g/plant), root and shoot reserve content, and AMF colonization were evaluated. The AMF inoculation promoted an accelerated vegetative growth, resulting in greater height and diameter. The fungi also promoted greater absorption of most of the nutrients and increase in all other parameters evaluated. However, no effect was found on the reserve content of the rootstock. Roots were colonized with moderate presence of arbuscules and low presence of vesicles. AMF, regardless of species, influence the development and physiology of the citrange 'Fepagro C37 Reck' rootstock.