Antonio Carlos Torres da Costa

Produtividade de milho cultivado em sucessão à adubação verde

The use of previous crops which have the capacity of supplying nitrogen to maize by symbiotic fixation or nutrient recycling is important to yield maintenance. This study aimed at evaluating the yield of maize grown in succession to green fertilization . A completely randomized blocks design was used with four replications and the following treatments: maize grown on black oat, black oat + oilseed radish, black oat + white lupin, white lupin, crambe, spontaneous vegetation (fallow ground) and spontaneous vegetation (fallow ground) + topdressing nitrogen fertilization. Concerning grain yield, significant differences were observed among treatments. The maize grown on black oat + white lupin straw reached the highest yield (10,817 kg ha -1 ), resulting in a higher income and differing from the one grown on black oat and crambe straw and spontaneous vegetation. The use of white lupin , black oat + white lupin and black oat + oilseed radish showed to be a viable alternative for a higher grain yield, making the topdressing nitrogen fertilization unnecessary.

Produção de biomassa de cultivares de aveia sob diferentes manejos de corte

In the crop -livestock integration system , improper oat management can result in low biomass yield. This study aimed to evaluate the effect of cutting management systems on the biomass yield of five oat cultivars with potential use in the crop-livestock integration system. A completely randomized blocks design with four replications, in a split-plot scheme, was used. The plots were represented by the oat cultivars Preta Comum, IAPAR 61, IPR 126, FAPA 2, and FUNDACEP FAPA 43. The Preta Comum cultivar features a short cycle, while the others have a long one . The sub-plots were represented by the following cutting systems: one single cut in the flowering stage, one cut in the vegetative and other in the flowering stage, two cuts in the vegetative and other in the flowering stage, and three cuts in the vegetative and other in the flowering stage. The long cycle cultivars (IAPAR 61, IPR 126, FAPA 2, and FUNDACEP FAPA 43) reached high forage yield, without affecting the subsequent fodder yield for soil covering, pointing out its ability to be used in crop-livestock systems. The management systems with three cuts in the vegetative stage maximizes the forage yield, however, concerning fodder yield, the best results were obtained by using up to two cuts in the vegetative stage, or a single one in the flowering stage.

Reação de resistência tipo I e tipo II a Giberela em cultivares de trigo

O objetivo deste trabalho foi avaliar as reacoes de resistencia tipo I e tipo II a giberela em 28 cultivares de trigo em casa de vegetacao. A inoculacao de Fusarium graminearum foi realizada no estadio de florescimento. Para a resistencia tipo I, a avaliacao foi feita 21 dias apos a inoculacao. Foi determinada a severidade no estadio de espiga seca e a porcentagem de graos giberelados. A avaliacao da severidade foi feita pela porcentagem de espiguetas infectadas, no estadio de espiga verde atribuindo-se uma nota em uma escala linear de zero (nenhuma infeccao) a 100 (100% de espiguetas infectadas). Para a resistencia tipo II, as avaliacoes foram realizadas aos 7, 14 e 21 dias apos a inoculacao, contando-se as espiguetas com sintomas da doenca, excluindo as duas espiguetas que foram inoculadas. As cultivares Frontana, BRS 177, BRS 179, BRS Umbu, BRS Camboim, Abalone, Onix, Pampeano e Fundacep 30 apresentaram menor severidade da doenca e menor porcentagem de graos giberelados, demonstrando serem fontes de resistencia tipo I. As cultivares BRS Guamirim, CD 120, Onix, Rubi, Fundacep 50, BRS 179, Pampeano, Abalone, CD 114, IPR 85, Safira, BRS Louro, CD 117, CDF 2002116, CD 115, BRS 177, CD 0529 e BRS Camboim apresentaram a menor area abaixo da curva de progresso da doenca, demonstrando a presenca da resistencia do tipo II.

Soybean productivity under different grazing heights of Brachiaria ruziziensis in an integrated crop-livestock system

The aim was to evaluate the effects of grazing height of Brachiaria ruziziensis on the production of straw, and the establishment and grain yield of a soybean crop, under an integrated crop-livestock system, on a typic dystrophic Red Latosol at the Experimental Farm of the Agronomic Institute of Parana (IAPAR), in Xambre, in the state of Parana, Brazil (PR). The study was carried out between September of 2010 and April of 2012. The experimental design was of randomised blocks, in lots split over time, with five treatments and three replications. The following were determined for the Brachiaria ruziziensis: shoot dry matter weight, plant residue dry matter weight, and total dry matter weight (Brachiaria ruziziensis shoot weight + plant residue weight). Also determined were variables related to the yield of the soybean crop (number of plants per metre, plant height and grain productivity), for the crop years 2010/2011 and 2011/2012. Straw production is greater in areas of Brachiaria ruziziensis where there is no grazing compared to areas where grazing occurs; the high production seen in areas with greater grazing heights should also be noted. The final number of plants, plant height and productivity in the soybean were not affected by the grazing height of the Brachiaria ruziziensis.

Características agronômicas de seis cultivares de amendoim cultivadas em sistema convencional e de semeadura direta

Objetivou-se no presente trabalho avaliar o desempenho agronomico de seis cultivares de amendoim em sistema convencional e de semeadura direta nos municipios de Marechal Cândido Rondon e Tupassi, PR, na safra 2011/2012. O delineamento experimental adotado foi de blocos ao acaso com quatro repeticoes num esquema de parcelas subdivididas. Foram utilizados, nas parcelas, dois sistemas de manejo de solo, o sistema convencional e sistema de semeadura direta e seis cultivares de amendoim de habito de crescimento contrastante, um de porte ereto e cinco de porte rasteiro, nas subparcelas. Nao houve diferenca entre os sistemas de manejo conservacionista e convencional no rendimento de vagens e graos, no numero de estruturas reprodutivas nem no indice de rendimento de graos do amendoim, nos dois locais avaliados. No municipio de Marechal Cândido Rondon as maiores produtividades foram obtidas pelos cultivares IAC 503, IAC Caiapo, IAC 213, Runner IAC 886 e Cavalo, respectivamente, independentemente do sistema de manejo de solo. Em Tupassi a produtividade de graos variou apenas entre os tipos de ramificacao dos materiais cujos maiores valores foram observados para cultivares de ramificacao alternada (Virginia).

Condições de ambiente favoráveis à germinação e à infecção de Puccinia substriata var. penicillariae em diferentes cultivares de milheto pérola

The rust caused by Puccinia substriata var. penicillariae in Pearl millet (Pennisetum glaucum) induces yield losses in this forage crop. Considering the lack of information about this disease in Brazil, this research on its epidemiology has been carried out. The mean latency period, the frequency of infection process and size of lesions on four genotypes of pearl millet (Pennisetum glaucum) ENA 1, Composto II, BRS 1501 and HKP were evaluated in the greenhouse. In vitro, the germination of the urediniospores was monitored at different temperatures (10, 15, 20 and 25oC), with or without light. After this, the infection process was compared for the genotypes Guerguera, Souna III, BRS 1501 and ENA 1, in a growth chamber, with the leaf wetting time of 0, 1, 2, 4, 8 and 12 hours, with or without light, and in greenhouse, on the genotypes ENA 1, Guerguera and Souna III, with the leaf wetting times of 3/4, 1, 2, 4, 6 and 8 hours. A mean latency period for pearl millet rust between 10 and 12 days was shown, and the urediniospores germinated in a wide range of temperatures, from 10 to 25oC, with or without light, with a maximum germination at 17.5oC in the dark. In these conditions, the germination of first spores initiated for less than 45 min at a maximum percentage of 88.2%, with 1.7 h of incubation. Leaf infection can also start after 45 min of leaf wetting after inoculation, but there is a beneficial effect of dark and longer leaf wetting time.

Reação de resistência tipo I à Giberela em cultivares de trigo

O objetivo deste trabalho foi avaliar a reacao de resistencia tipo I a Giberela em 28 cultivares de trigo em experimentos conduzidos a campo, em duas epocas de semeadura (maio e junho). Em ambas as epocas foi utilizado o delineamento em blocos casualizados, composto por 28 tratamentos (cultivares) e quatro repeticoes. Para a dispersao do inoculo de Gibberela zeae na area foram utilizados graos de trigo com peritecios do patogeno. Ao inicio do florescimento, em dias sem precipitacao pluviometrica, a area experimental foi submetida ao molhamento de espigas com formacao de neblina por 5 minutos consecutivos, a intervalos de 25 a 30 minutos. A avaliacao da severidade da doenca foi feita 21 dias apos a inoculacao, no estadio de espiga verde, atribuindo-se uma nota em uma escala linear de zero a 100, baseada na escala sugerida por Stack e McMullen. No estadio de espiga seca foi determinada a porcentagem de graos giberelados. As cultivares Frontana, BRS 177, Safira e BRS Timbauva estiveram no grupo com menor media de severidade da doenca quando se consideram as duas epocas de semeadura conjuntamente. Na avaliacao de graos giberelados, as cultivares BRS 177, Onix, BRS Timbauva, BRS Umbu, BRS Guamirim, CEP Raizes, CEP 50, CD 120 e CD 0529 estiveram, nas duas epocas, no grupo com menor media de incidencia.

Dias para espigamento, altura de plantas e índice de acamamento em genótipos de trigo

With the aim of evaluating the time in days to silking , plant height and lodging index of wheat genotypes , an experiment was conducted, in 2012, in the experimental field of Central Cooperative for Agricultural Research ( COODETEC) in Palotina (Parana, Brazil). The experimental design was a randomized complete block design with three replications, involving 15 treatments consisting of three cultivars – CD 150, Frontana and Mirante – and 12 parental lines derived from crosses of the cultivars CD 150 and Frontana . The a nalysis of variance showed differences among genotypes, indicating the presence of genetic variability for the traits days to silking and plant height . The crosses of CD 150 and Frontana resulted in lines from early to mid life cycle, with short plants , contributing to lower rates of lodging.

Ocorrência da ferrugem (Puccinia substriata var. penicillariae) do milheto na região Oeste do Estado do Paraná

(L) R. Brown] e utilizadono Brasil para producao de forragem e para a producao de graos usadono fabrico de racao animal. Nos ultimos anos, esta cultura se tornou defundamental importância para a producao de palhada no sistema deplantio direto, havendo um aumento consideravel da area plantada.Entretanto, um grande problema economico para esta cultura tem sidoa ferrugem, pois os danos causados por esta doenca resultam emreducao de rendimento de ate 75% da producao de graos, alem dereduzir tanto a producao de biomassa como a qualidade da forragem.No Brasil, sintomas de ferrugem nas folhas de milheto foraminicialmente observados em 1997, na area experimental da Embrapa -Cerrados, em lavouras comerciais no Distrito Federal e em municipiosvizinhos de Minas Gerais e Goias e, em 1999, na area experimental no