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ABSTRACT To study the efficiency of Asian soybean rust (Phakopsora pachyrhizi) control and to test the effects of using alternative products and fungicides, two field experiments were conducted during the harvest seasons 2013/2014 and 2014/2015. Treatments for the experiments were: 1- control (water); 2- acibenzolar-S-methyl; 3- calcium; 4- micronutrients: copper, manganese and zinc; 5- micronutrients: manganese, zinc and molybdenum; 6- NK fertilizer; 7- Ascophyllum nodosum, and 8- azoxystrobin + cyproconazole. The evaluated variables were: Asian soybean rust severity, defoliation, productivity and yield components. Based on severity data, the area under the disease progress curve was calculated. In the two experiments, the alternative products had no effect on Asian soybean rust or defoliation. Only the treatment with fungicide controlled the disease and decreased defoliation. The yield component affected by the treatments was the number of pods per plant, in both harvest seasons. Treatment with the fungicide protected soybean from yield loss in both experiments. Defoliation was strongly correlated with the weight of one thousand seeds and the number of pods per plant, emphasizing the importance of maintaining the leaf area to ensure the maintenance of the yield components in soybean crop.

Trichoderma asperellum e Bacillus subtilis como antagonistas no crescimento de fungos fitopatogênicos in vitroTrichoderma asperellum and Bacillus subtilis as antagonists in the growth of phytopathogenic fungi in vitro

The interest in the use of microorganisms in agricultural practices has increased significantly in recent years, both in the promotion of plant growth and in the biological control of plant pests and diseases. This literature review work aimed to address information on the use of isolation, multiplication, use and storage methodologies for efficient microorganisms (Effective Microorganisms, EM) in agriculture. These microorganisms have important functions for their hosts, as they have symbiotic interactions with them, and are capable of protecting plants from attack by insects, diseases and herbivorous mammals through the production of toxins. The use of EM in agriculture aims to accelerate the natural composition of organic matter and promote the balance of microbial flora contributing to plant development. EMs are potential substitutes for chemical products, and can thus favor the preservation of the environment. They are collected from fertile forest soils through simple and inexpensive methodologies, consisting of a tool with potential to be used both by family farmers and on a small and large scale. They can be used in different ways, the main ones being in soil, plant, water and animals. The use of EM is an accessible and low-cost technique, in addition to being easy to prepare within the property itself, contributing to the sustainability of agricultural systems.

Among the diseases that manifest in the cultivation of oats (Avena sativa), leaf rust, caused by Puccinia coronata f. sp. avenae, has been shown to be the most destructive, being responsible for the decrease in quality and grain yield. Nutritional balance can contribute to plant resistance to disease. In order to evaluate the effect of different doses of calcium and sulfur on leaf rust severity and on the productivity of the IPR Afrodite white oat cultivar, an experiment was installed in the municipality of Ponta Grossa-PR. The experimental design used was randomized blocks, with 5 treatments and 4 repetitions. The treatments consisted of different doses of SE-SUPER fertilizer (CaO 31% + S 13.50%) applied at sowing: T1 (control, 0Kg.há -1 ), T2 (50Kg.há -1 ), T3 (100kg.ha -1 ), T4 (150kg.ha -1 ) and T5 (200kg.ha -1 ). The assessments of leaf rust incidence and severity are carried out weekly from the first symptoms, by quantifying the proportion of the affected host tissue. From the first assessment, weekly assessments were carried out, making it possible to calculate the area under the disease progress curve (AUDPG). For the determination of productivity, the yield in kg of grains / ha was calculated, based on the harvested experimental area. There was a difference between treatments for the severity of rust in the six evaluations performed. All doses were equivalent in reducing the AUDPG of the disease, but the treatments with 150 and 200 kg.ha -1 of SE SUPER, presented the highest percentages of reduction, 47.21 and 48.00%, respectively. There was no difference in the productivity obtained. Other management strategies must be associated with fertilization with calcium and sulfur to control rust. Other management strategies should be associated with fertilization with calcium and sulfur, contributing to the rational use of pesticides and reducing pollution.The characteristics linked to the yield most affected by the occurrence of the disease are the average weight of Nádia Macoski et al.

Plum (Prunus salicina Lindl.) cultivation is seriously compromised in Brazil due to the occurrence of leaf scald, a disease caused by the bacterium Xylella fastidiosa subsp. multiplex. The objective of this study was to evaluate plum genotypes agronomically promising for resistance to leaf scald, under natural conditions of occurrence of the disease. Ten out of 50 plum genotypes belonging to the germplasm bank of “Instituto Agronômico do Paraná (IAPAR)” were selected. Five evaluations of leaf scald severity were carried out from January to February (2017 and 2018). Polymerase chain reaction (PCR) was also performed for samples of these genotypes to determine the presence of the bacterium X. fastidiosa subsp. multiplex. The genotypes differed in relation to their susceptibility to leaf scald. PR-1095 was the most resistant genotype and did not show any leaf symptom of the disease. In contrast, genotypes PR-1126 and PR-1137 had the greatest susceptibility to the disease, showing severe scald symptoms. However, PCR revealed the presence of the bacterium even in the most resistant genotypes, indicating, for example, that PR-1095, which had no symptoms of the disease, is probably tolerant to leaf scald.

repetições. Foram avaliados a assimilação liquida de CO2, a condutância estomática, a transpiração foliar, eficiência fisiológica do uso da água (EUAfis), as clorofilas α, β e total, bem como a produtividade. Nas duas safras, a cultivar TMG 7062 RR Inox apresentou maior condutância estomática, assimilação de CO2 e transpiração, em relação à NA 5909 RG. Independentemente do produto aplicado, a cultivar TMG 7062 RR Inox apresentou maiores teores de clorofila α, β e total em relação a cultivar NA 5909 RG. Constatou-se que o fungicida elevou os teores de clorofila α, β e total na cultivar TMG 7062 RR Inox, com incremento na clorofila total de aproximadamente 12,43% ao observado nos demais produtos e 27,03% em relação a cultivar NA 5909 RG. A aplicação do fungicida evitou danos ao rendimento da soja

The aim of the present study was to diagnose clinical and subclinical bovine mastitis in a property in the municipality of Carambeí-PR. 86 dairy cows were diagnosed in two evaluations carried out on July 23 and November 4, 2020. The detection of clinical mastitis was performed by testing the black-bottomed mug, whereas the detection of animals with sub-clinical mastitis by the California Mastitis Test (CMT) and laboratory analysis of bacteria and fungi present. In the first evaluation, 9.4% of the animals had mastitis, while in the second 5.16% of the herd. The milk of the animals that tested positive were submitted to laboratory analysis. In the first evaluation, they were diagnosed with an incidence of 15% Escherichia coli, 15% Prothoteca / yeast, 23% Staphlococcus aureus, 46% Streptococcus agalactiae. In the second evaluation, there was an incidence of 25% Enterococcus sp. and 25% S. agalactiae, the other animals showed 50% Staphlococcus non aureus. There was a higher occurrence of subclinical mastitis in the property, in both evaluations. There was a reduction from the first to the second evaluation in the incidence of cases of subclinical mastitis and the cases of clinical mastitis were resolved. Contributing to the lower disposal of milk caused by the high somatic cell count.