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Resumo ? Objetivou-se neste trabalho avaliar a eficiência de diferentes fungicidas no manejo da brusone em trigo tropical, em Planaltina, DF, nos anos de 2011, 2012, 2014, 2017, 2018 e 2020, quantificando a incidência, a severidade da doença e o rendimento de grãos. Avaliaram-se 16 tratamentos, entre produtos comerciais aplicados isoladamente em diferentes doses ou em misturas, nos 6 anos. Foram observadas diferenças significativas de incidência e severidade da doença em estudo nos anos 2012, 2017, 2018 e 2020. Quanto à produtividade, houve diferenças significativas nos anos de 2011, 2014, 2018 e 2020. A incidência da brusone variou de 4,0% a 100%; a severidade, de 1,9% a 97,8%; e o índice de doença, de 0,08 a 97,8. A principal proposição é a de que a variação nos valores dessas variáveis esteja associada à do clima durante a condução de cada ensaio. Em 2014, 2018 e 2020, a fase de espigamento do trigo coincidiu com um período chuvoso, o que proporcionou altos níveis de incidência e severidade. A produtividade do trigo variou de 15,6 kg ha-1 a 2279 kg ha-1 no sequeiro, enquanto, no sistema irrigado, variou de 4.066 kg ha-1 a 4.754 kg ha-1. A variação de produtividade ocorreu principalmente devido às condições climáticas favoráveis à incidência de brusone nas espigas.

Wheat blast, caused by Pyricularia oryzae Triticum (PoT) lineage, is a major constraint to wheat production, mainly in the tropics of Brazil where severe epidemics have been more frequent. We analyzed disease and wheat yield data from uniform field trials conducted during nine years (2012 to 2020) in order to assess whether the percent control and yield response were influenced by fungicide type, region (tropical or subtropical), and year. Six treatments were selected, all evaluated in at least 19 trials. Two ungicides were applied as solo active ingredients: MANCozeb, and TEBUconazole, and four were premixes: AZOXystrobin + TEBU, TriFLoXystrobin + PROThioconazole, TFLX + TEBU, and PYRAclostrobin + EPOXiconazole. Percent control, calculated from back- ransforming estimates by a meta-analysis network model fitted to the log of the means, ranged from 43 to 58%, with all but PYRA + EPOX showing efficacy greater than 52% on average, not differing among them. The variation in both efficacy and yield response was explained by region and all but TEBU performed better in the subtropics Than in the tropics. Yield response from using three sequential sprays was around two times greater in the subtropics (319 to 532 kg/ha) than in the tropics (149 to 241.3 kg/ha). No significant decline in fungicide efficacy or yield response was observed in nine years of study for any of the fungicides. Our results reinforce the need to improve control by adopting an integrated management approach in the tropics given the poorer performance and lower profitability, especially for the premixes, than in the subtropics. Keywords: Pyricularia oryzae, chemical control, profitability, meta-analysis Made available in DSpace on 2021-11-26T02:11:36Z (GMT). No. of bitstreams: 1 pdis-06-21-1183-re.pdf: 890336 bytes, checksum: 9cf106800d88860a7b603346c97083ae (MD5) Previous issue date: 2021

Fusarium head blight (FHB), caused mainly by Fusarium graminearum, is best controlled with demethylation inhibitor (DMI) fungicides during flowering. However, the use of premixes of DMI and quinone outside inhibitor (QoI) fungicides to control FHB has increased in Brazil. Data on FHB severity and wheat yields measured in field experiments conducted in Brazil were gathered from both peer- and non-peer-reviewed sources published from 2000 to 2018. After applying selection criteria, 73 field trials from 35 bibliographic sources were identified, among which 50% of the data were obtained from cooperative network trials conducted after 2011. To be included in the analysis, a DMI+QoI premixes or tebuconazole (TEB) were tested in at least 14 trials and three years. Four premixes met the criteria. Estimates of percent control (and respective 95% confidence interval) by a network model fitted to the log of the treatment means ranged from 44.1% (pyraclostrobin + metconazole applied once; 32.4 to 53.7) to 64.3% (pyraclostrobin + metconazole; 58.4 to 69.3); the latter not differing from TEB (59.9%, 53.6 to 65.3). Yield response was statistically similar for pyraclostrobin + metconazole (532.1 kg/ha, 441 to 623) and trifloxystrobin + prothioconazole (494.9 kg/ha, 385 to 551), and both differed statistically from a group composed of TEB (448.2 kg/ha, 342 to 554), trifloxystrobin + TEB (468.2 kg/ha, 385 to 551), azoxystrobin + TEB (462.4 kg/ha, 366 to 558) and pyraclostrobin + metconazole applied once (413.7 kg/ha, 308 to 518). The two categories of FHB index (7% cut off) and yield (3,000 kg/ha cut off), both in the non-treated check, did not explain the heterogeneity in the estimates. Two sequential sprays of TEB or one spray of pyraclostrobin + metconazole as management choices are likely more profitable than DIM+QoI premixes sprayed twice during flowering considering only the fungicide effects on yield. Keywords: chemical control; Fusarium graminearum, meta-analysis; profitability; systematic review Made available in DSpace on 2021-02-17T18:20:07Z (GMT). No. of bitstreams: 1 pdis-09-20-2096-re.pdf: 1173033 bytes, checksum: bce85558f3794036e33197f9751d335c (MD5) Previous issue date: 2020

Os principais aspectos relacionados às doenças bióticas mais comuns na cultura do trigo no Brasil são apresentados a seguir. Made available in DSpace on 2020-12-10T09:01:32Z (GMT). No. of bitstreams: 1 Artigo-pronto-publicado-em-abril-de-2020.pdf: 2068880 bytes, checksum: 4448c52fd9f22a46ab7cfd81ea6cbe51 (MD5) Previous issue date: 2020

In wheat breeding, several strategies are applied to improve grain yield. Annually, a great number of cultivars of different origins are crossed. The plants derived from these segregating populations are exposed to the most diverse possible stresses to develop new cultivars with maximum technical and economic efficiency and generate improvements to maximize the economic-environmental sustainability of plantations, while maintaining or increasing the yield potential. Made available in DSpace on 2020-09-18T04:38:34Z (GMT). No. of bitstreams: 1 AWN-VOL-66-p8-11pdf.pdf: 379271 bytes, checksum: d9ef470b0050ff60aa934ed4cce7fed3 (MD5) Previous issue date: 2020

Made available in DSpace on 2019-12-18T00:37:43Z (GMT). No. of bitstreams: 1 ID448332019v65p7AWN.pdf: 485272 bytes, checksum: c23daec7283beb33479bcf322430f6a3 (MD5) Previous issue date: 2019

Made available in DSpace on 2014-03-11T23:26:52Z (GMT). No. of bitstreams: 1 art3A10.10072Fs126000130316y.pdf: 313894 bytes, checksum: 5e80026177acb18bd8d6314ba25d2bb4 (MD5) Previous issue date: 2014-03-10

Made available in DSpace on 2011-04-09T16:13:47Z (GMT). No. of bitstreams: 1 santanadetec.pdf: 178584 bytes, checksum: a72e615b6fef0903082cce2e072855a5 (MD5) Previous issue date: 2007-03-28

The oceanic whitetip shark, Carcharhinus longimanus, represented 29% of the elasmobranch catch in 197 longline sets conducted off Brazil in the equatorial Atlantic (1°N to 9°S, 30° to 40°W) from 1992 to 1997. A total of 258 individuals were caught (121 males and 137 females) ranging from 71 cm to 250 cm (total length, TL). No significant difference was detected in the length vs eviscerated weight relationship between sexes. Significant differences between sexes were found for twelve morphometric features. Claspers 2.6-21.0 cm in length were found in males measuring 114 to 235 cm. In individuals up to 187 cm, claspers are flexible and smaller than 10 cm. A substantial increment in size of claspers occurred in 190 cm individuals. Testes ranging from 3 to 170 g were recorded in individuals 95 to 235 cm in length and epididymis width varied from 0.4 in to 2.4 cm. In females, nidamental gland width varied between 0.5 to 4.4 cm in 105 to 250 cm. Ovary weights from 5 to 180 g were recorded. Vitellogenic follicles were not observed in females smaller than 180 cm, but in larger individuals they vary from 1.0-4.4 cm. Liver weights ranged from 180 g in a 100 cm female to 7,500 g in a 250 pregnant female. First maturity class is 180-190 cm for both sexes. Three pregnant females (203, 213 and 250 cm in length) were caught with embryos of approximately 20 cm (n = 3), 10 cm (n = 4), and fertilised eggs (n = 9), respectively. Males and females were longer and heavier from July through December. Testis and liver weights in males were also significantly higher during this period. The mean weight of ovaries and follicle diameter decrease during this period which can be attributed to ovulation. A new-born shark caught in August with an unhealed umbilical scar suggested that birth takes place at about 70 cm.