Flávio Sérgio Afférri

Densidade de plantio em duas cultivares de mamona no Sul do Tocantins

Abstract - In order to improve the system of production of castor oil, you need to determine the density of plants. It was conducted an experiment in the Cariri, Tocantins-TO, at the Fazenda Coqueiro, using seeds of BRS Nordestina and BRS Paraguacu to verify the effect of five planting densities (2.5; 3.12; 4.16; 6.25 and 12.5 thousand plants ha -1 ) on yield and agronomic characteristics of castor. The experiment was installed in February 2006 with all plants receiving the same fertiliza tion independent of density (NPK 5-25-15). The experimental design was randomized blocks with four replications and treatments arranged in a 5 x 2 x 3, for analysis of grain yields and in a 5 x 2 for the other traits evaluated. The treatments resulted in the combination of five densities (distance between plants growing 2.00; 1.60; 1.20; 0.80 and 0.40 m) for the 2.5; 3.12; 4.16; 6.25 and 12.5 thousand plants per hectare respectively, two cultivars (BRS Nordestina and BRS Paraguacu) and three crops of fruit on the following dates: 06/07/2006; 03/08/2006 and 19/09/2006. Among the populations, the highest productivity was 12.5 thousand plants ha

Eficiência no uso de nitrogênio e correlação fenotípica em populações tropicais de milho no Tocantins 1

of Moll was possible to differentiate populations for nitrogen use efficiency in environment of low availability of soil N. The characteristics evaluated were influenced by different levels of nitrogen, except for 100 seeds weight. The populations studied differ itself in all characteristics, indicating variability. Moll index was significantly associated with all characteristics studied except for the Fischer index, indicating possible to obtain genotypes efficient in nitrogen use by selection of these characteristics.

Comportamento de cultivares de soja, em diferentes épocas de semeaduras, visando a produção de biocombustivel

The sowing season is defined by a set of environmental factors that react with each other and interact with the plant, thus affecting variations in production and other agronomic traits. This work was carried out to evaluate the behavior of 21 cultivars of commercial soybean, during different times, looking forward to the production of biofuel. Were conducted five essays in the 2008/09 agricultural year, being two of them in Palmas-TO and three in Gurupi-TO. The sowing in Gurupi-TO was in 03/12/08, 18/12/2008 and 05/01/2009,and in Palmas in 30/11/2009 and 16/12/2009. The experimental design was a randomized blocks with 21 treatments and three repetitions. The treatments were constituted on the cultivars P98Y70, M-SOY 8766RR, M-SOY 9144RR, BR/Emgopa 314, P98R91, P98Y51, M-SOY 9988RR, P99R01, M-SOY 8867RR, M-SOY 9056RR, M-SOY 8527RR, M-SOY 8360RR, FT ESPERANCA, FTS 4188, CM 07, CM 017, CM 136, CM 149, CM 102, NIDERA A 7002 and M-SOY 9350. The following characteristics, were evoluated production of grains, oil content of the grain and oil yield. Significant differences were detected among cultivars, sowing season and cultivate x sowing season for all characteristics. The first planting time in Palmas (30/11) and Gurupi (03/12), were the most favorable to the development of cultivars. There was positive and significant association between oil yield and production of grains (R = 0.97). Higher temperatures and rainfall precipitation averages, during the phase of stuffing of grains, favored the oil accumulation in the grains. NIDERA A 7002, MSOY 9144RR, BR/Emgopa 314, P98Y51 and FTS 4188 were the best cultivars for oil content of the grain and oil yield.

Adaptabilidade e estabilidade de genótipos de soja em Tocantins.

Objetivou-se com este trabalho estudar a estabilidade fenotipica de cultivares de soja, quanto a producao de graos, em oito ensaios, quatro na cidade de Gurupi-TO e, quatro na cidade de Palmas - TO, conduzidos durante os anos de 2008 a 2012. Os ensaios foram instalados com delineamento em blocos casualizados, com quatro repeticoes, e onze cultivares de soja. Foram utilizadas as metodologias de analise de estabilidade de Eberhart e Russell (1966), Lin e Binns (1988) modificado por Carneiro (1998), e Annicchiarico (1992) e tambem, as de Lin (1982) e Cruz e Castoldi (1991) nas analises de estratificacao e dissimilaridade ambiental. A producao media das cultivares nos ensaios foi de 2.931 kg ha-1 de graos. O resultado da analise de variância conjunta mostrou efeitos significativos dos ambientes (ensaios) e da interacao G x A, a qual foi predominantemente do tipo complexa para todos os pares de ensaios. O genotipo TMG 131 RR foi mais adequado em ambas as condicoes ambientais (desfavoraveis e favoraveis), tendendo para as desfavoraveis. E o genotipo TMG 132 RR para as favoraveis. As metodologias utilizadas, de modo geral, se completam e, quando usadas conjuntamente, podem aumentar a confianca quanto a classificacao e indicacao de cultivares de soja para determinados ambientes.

Nitrogênio em cobertura no estudo de dois grupos de genótipos de milho em Gurupi-TO

The nitrogen is the most absorbed nutrient by maize, and its supply after seeding is common. However, its available for the plants is associate with soil and weather conditions and with kind of genetic material that is used, due the yield potential and the genetic base. This paper had the aim to evaluate two maize genotype groups at levels of nitrogen in covered, in Gurupi, Tocantins State, Brazil, season 2012/13. The experiments with 30 genotypes had two levels of covered nitrogen (0 and 150 kg ha -1 ) and they were seeding in two dates. The experiments with 12 genotypes had three levels of covered nitrogen (20; 80; 140 kg ha -1 ) and they were seeding in four dates. The experimental design was randomized blocks with three replications. For the analysis of variance, the experiments were clustering in accordance with the seeding date for the evaluation the effects of genotypes and covered nitrogen. In the two genotypes groups were not observed the significant interaction between the sources of variation. The leaf chlorophyll, between stages VT-R1, was the most sensible with the change of covered nitrogen level.