Determination of the optimal quantity of crop residues for energy in sugarcane crop management using linear programming in variety selection and planting strategy

The aim of this work was to present organizational models for optimizing the reduction of crop residue generated by the sugarcane culture. The first model consisted of the selection of varieties of sugarcane to be planted meeting the mill requirements and, at the same time, to minimize the quantity of residue produced. The second model discussed the use of residue to produce energy. This is related to the selection of variety and quantity to be planted, in order to meet the requirements of the mill, to reduce the quantity of residue, and to maximize as much as possible the energy production. The use of linear programming was proposed. The two models presented similar results in this study, and both may be used to define the varieties and areas to be cultivated. (C) 2001 Published by Elsevier B.V. Ltd.

Planting of fungus onto hibernating workers of the fungus-growing ant Mycetosoritis clorindae (Attini, Formicidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Produtividade da beterraba e rúcula em função da época de plantio em monocultivo e consórcio

Avaliou-se os rendimentos das culturas da beterraba e da rúcula em função de épocas de plantio e sistemas solteiro e consorciado, em Mossoró, de janeiro a março de 2005. O delineamento experimental utilizado foi de blocos casualizados com nove tratamentos em quatro repetições. Os tratamentos consistiram dos consórcios da beterraba com rúcula estabelecidos aos 0, 7, 14 e 21 dias após a semeadura da beterraba, monocultura da beterraba e as monoculturas da rúcula, nas mesmas épocas de estabelecimento dos cultivos consorciados. A semeadura da rúcula e beterraba realizada na mesma época proporcionaram maior massa fresca e seca da parte aérea e produtividade de rúcula, sendo respectivamente, de 50,19 g/planta; 5,86 g/planta e 1338,47 g/m². Já para a beterraba, independentemente da época de semeadura, o monocultivo foi superior ao consórcio na produção de massa fresca e de raízes. Os maiores índices de uso eficiente da terra foram obtidos no sistema de consórcio quando a semeadura da rúcula foi realizada no mesmo período (2,0) e aos sete dias (1,9) após a semeadura da beterraba.

Quality of mechanized coffee harvesting in circular planting system

A colheita mecanizada de café se destaca como um dos principais avanços tecnológicos em benefício dos produtores, porém, problemas com planejamento no plantio e desenvolvimento da cultura, bem como falhas na regulagem da colhedora, podem acarretar em redução na eficiência da operação, tornando-a mais estressante para a cultura que a colheita manual. Diante disso, o presente trabalho foi realizado no município de Patos de Minas, MG, com o objetivo de avaliar os danos na parte vegetativa e a qualidade da colheita mecanizada do café cultivado em plantio circular sob pivô central, com duas frequências de vibração das hastes, sob o controle estatístico do processo. Observou-se que a bienalidade negativa sobre a cultura reduziram a carga inicial de café, eliminando o efeito das condições de insolação. Os índices de qualidade da colheita apresentaram distribuição assimétrica, com grande variabilidade nas amostras, sendo apenas a eficiência de derriça influenciada pelos eixos avaliados, e se mostrando estável pelo controle estatístico. Os danos causados às plantas pela colheita apresentaram valores desejáveis, não variando em função dos fatores analisados, mas sendo considerado sob controle estatístico.

Planting time, developmental stages and characteristics of roots and starch of Pachyrhizus ahipa

De forma geral, as características do amido variam não somente com a planta de origem, mas também com o estádio de desenvolvimento desta. Neste trabalho objetivou-se avaliar a influência da época de plantio e estádio de desenvolvimento da planta de ahipa sobre as características físico-químicas das raízes, tamanho de grânulos do amido e suas propriedades viscográficas. Constatou-se influência do estádio de desenvolvimento da planta nas características físico-químicas das raízes e do amido, independentemente da época de plantio. A melhor época para o plantio de Pachyrhizus ahipa é outubro e a colheita deve ser feita no máximo com 9 meses, adotando-se o procedimento de retirada das flores a partir dos 3 meses.

Effect of sowing date on the behavior of 2 genotypes of sunflower .1. phenological and agronomical aspects

Este experimento foi realizado em .iaboticabal, SP, com o objetivo de se avaliar o comportamento de dois genótipos de girassol (líeIianthus annuus L.) no tocante à produção dc matéria seca e caracte r ísticas agronômicas. Utilizou-se o híbrido Contissol 812 e a cultivar IAC-Anhandy com 80 cm entre linhas e 5 plantas por metro linear, em blocos casualizados, com quatro repetições cm cinco datas de semcadura: 2001, 2002, 05.03, 2003 e 05.04. O atraso das datas de semeadura exerceu efeito depressivo e significativo sobre a produção e distribuição de matéria seca (kg/ha) no caule, folha, capítulo e no total, reduzindo também significativamente o número de dias de emergência ao florescimento, a altura das plantas, o número de folhas, e os diãmetros do colo e do capitulo. A produ- ção média de aqüõnios foi de: 2.942, 2.005, 1.243. 1.073 e 809 kg/ha, da primeira ã última data, rcspectivamente, nos dois genótipos. Concluiu-se que os dois genótipos se comportaram de forma scmc' lhante nas diferentes datas, e que as semeaduras realizadas até o final de fevereiro foram as melhores, e nas efetuadas posteriormente, o crescimento e o desenvolvimento das plantas foram afetados negativamente, levando a produção de aqüênios a níveis indesejáveis.

The effects of pre-planting refrigeration on bulbs over the development and yield of garlic 'Chines', 'Contestado' and 'Quiteria'

The objective of this research uas to evaluate the effect of five pre-planting refrigeration periods previously to the cloves planting (0,10,20, 30 and 40 days at a temperature of 4.0 ± 1° C and three garlic cultivars ('Chines', 'Contestado' and 'Quiteria') uere used. According to the obtained results it was observed that the best preplanting refrigeration period was dependent upon the cultivar behavior. For the 'Chines' well adapted to the region, there was no effect of the pre-planting refrigeration period up to 30 days after treatment on the plant height, bulb weight, and total bulb production. 'Contestado' the best pre-planting refrigeration period was 40 days however, there was no statistical difference among 30 and 40, days for the 'Quiteria'. For both cultivars pre-planting refrigeration periods under 20 days, there was no clove's formation.

Effect of Alternaria cassiae, Pseudocercospora nigricans, and soybean (Glycine max) planting density on the biological control of sicklepod (Senna obtusifolia)

The interactions of two fungal biocontrol agents, Alternaria cassiae and Pseudocercospora nigricans, and soybean planting density on sicklepod mortality and dry weight were studied in the field over 2 yr. The experimental field was divided into three equal areas: one without soybean and two where the soybean was sown in densities of 20 and 36 seeds per meter row with a 0.95-m row spacing. The fungi were sprayed alone or in a mixture at three growth stages of sicklepod plants grown at three levels of crop interference resulting from the three soybean planting densities. The fungal treatments were: an untreated control, A. cassiae (105 spores/m2), P. nigricans (3.3 g mycelium/m2), and the mixture of these two fungi. Sicklepod was at the cotyledonary leaf, two-leaf, and four-leaf stages when treated. Alternaria cassiae was most effective in reducing both sicklepod survival and dry weight. The mixture of P. nigricans and A. cassiae was generally comparable to but not better than A. cassiae alone in killing the weed (mortality) and reducing its growth (dry weight). Soybean density did not have significant effects on the mortality or the dry weight of sicklepod. Thus, there is no advantage to combining the highly effective biocontrol agent A. cassiae with the less effective P. nigricans or with soybean interference to control sicklepod. However, the results validate the efficacy of A. cassiae by itself as a bioherbicide.

Digital image analysis of root distribution towards improved irrigation water and soil management: Grapevine and date palm study cases

It is presented two study cases about the approach in root analysis at field and laboratory conditions based on digital image analysis. Grapevine (Vitis vinifera L.) and date palm (Phoenix dactylifera L.) root systems were analyzed by both the monolith and trench wall method aided by digital image analysis. Correlation between root parameters and their fractional distribution over the soil profile were obtained, as well as the root diameter estimation. Results have shown the feasibility of digital image analysis for evaluation of root distribution.

Cultivation systems and planting seasons effects on the vegetative growing of net melon cultivars

Growth effects of cultivation on soil, sand and commercial substrate, on summer and winter time, of 'Bonus #2', 'Don Carlo's and 'Hy Mark' were assessed. The experiments were conducted in a greenhouse of FCAV-UNESP, in Jaboticabal- SP, Brazil, 21° 15' 22 S, 48° 18'58 W, and an altitude of 595 m, comprising the period from November '99 to April 2000 (Summer), and from July to November 2000 (Winter). On soil cultivation, chemical nutrients were used, and the plants received drip irrigation. On sand, fertigation with recirculation of the nutrient solution were used, and slabs and fertigation with non circulating nutrient solution was used with commercial substrate. 'Bonus #2', grown on sand and in the summer season had improved plant height, internodes length, stem diameter, leaf area and dry matter of shoots and roots. 'Hy Mark', when cultivated on commercial substrate had lower growth. During winter season, the growth was slower.

Total and harvest-date yield of processing tomato cultivars

The productivity of 28 tomato cultivars was evaluated over three stages of harvest. The study was carried out during from June to December of 1999 in an open field at the experimental area of the Section of Olericulture and Aromatic Medicinal Plants, Department of Crop Production at FCAV-UNESP, Jaboticabal, SP, Brazil. The cultivars studied were H 7155, Hypeel, Andino, U 573, H 9036, IPA 6, H 9494, AG 33, Yuba, RPT 1294, AG 72, Pelmeech, Curico, Hypeel 45, RPT 1478, H 9492, H 9498, H 2710, Hitech 45, Halley, Botu 13, H 9553, U 646, NK 1570, AG 45, RPT 1095, RPT 1570, and PSX 37511. The experimental design was a randomized block design with four repetitions, with five plants per plot. Productivity was evaluated at three stages of harvest at 119, 149 and 179 days after seeding. There were no significant differences among the cultivars at the first harvest (119 days). The majority of the cultivars produced their highest yield at the second harvest; the most productive cultivars were Curicó and AG 72, which yielded 4.69 and 4.67 kg/plant, respectively, although they did not differ statistically from the cultivars Hypeel 45 (4.35 kg/plant) and H 9498 (4.16 kg/plant). Yields of the cultivars Andino and H 9494 were evenly distributed between the second and third harvests. At the third harvest, cultivar IPA 6 had the highest yield (2.9 kg/plant) and was statistically different from all other cultivars except H 9036 (2.34 kg). These two cultivars had the most delayed and concentrated maturity, making them suitable for mechanical harvesting, although at a later time. Cultivar AG 72 had the greatest total yield (5.76 kg/plant), but it was not statistically different from cultivars Hypeel 45 (5.43 kg), Curico (4.17 kg), H 9498 (4.83 kg), H 7155 (4.58 kg) and Halley (4.55 kg). All of the cultivars, with the exception of cultivars H 9036, IPA 6, Andino and H 9494 showed in the second harvest concentrated maturity, making it suitable for mechanical harvesting.

Forage mass production and grazing loss of sorghum hybrid in response to the density of the sowing and the spacing between planting lines

The objective of this experiment was to evaluate dry matter yield and loss of grazing due to animal trampling in response to sowing density and spacing between lines in the planting. Sorghum hybrid 1P400 was submitted to six treatments, composed of three sowing density combinations (12; 16 and 20 kg/ha of seeds) and two spacing between lines (0.40 and 0.80 m). Sorghum hybrid 1P400 was sowed in two seasons, at the end of spring (December 3rd, 2005) and the other at the end of summer (March 20th, 2006). Cultivation strategies influenced plant population in the two experimental seasons. Diameter of the stem in season 1 decreased with density increase, whereas in the second season, interaction between sowing density and spacing was significant. In the first season, 0.40-m spacing promoted greater losses due to grazing stepping, that is, 891 kg/ha of DM, whereas in the second season there was no statistical difference. There was no significant difference in forage dry matter yield in sowing densities among the two studied seasons. Dry mater production of sorghum hybrids 1P400 did not increase with the increase of the sowing density in the two sowing seasons, therefore it is recommended 12 kg/ha of seeds for the sowing. Sorghum IP400 cultivated in 0.80-m spacing resulted in lower forage loss caused by grazing bovine trampling. © 2011 Sociedade Brasileira de Zootecnia.

Performance of cultivars of crisp mini-lettuce with respect to ground cover and spacing, in three planting times

The planting of lettuce in greenhouses, as well as covering beds with a polyethylene sheet, is a viable technology, promoting improvements in microclimatic conditions of the environment. In view of the little information on mini-lettuce, the aim of this work was to evaluate the performance of three cultivars of crisp minilettuce ('Green Frizzly', 'Red Frizzly no. 1' and 'Red Frizzly no. 2') with and without ground cover, under different spacings (20 × 15 cm and 20 × 20 cm), in three planting times (1: November 16, 2004; 2: December 17, 2004; and 3: January 20, 2005). The study was conducted in a greenhouse at UNESP-FCAV, Jaboticabal-SP. The experiments were carried out using a randomized block design, following a 3 × 2 × 2 factorial scheme with 12 treatments and three repetitions. The characteristics evaluated were plant height (cm), head diameter (cm), fresh weight (g) and number of leaves per plant. Planting time 3 was shown to be favorable for all the characteristics analyzed. 'Red Frizzly no. 2' was found to be the most suited to planting time 1, and for planting times 2 and 3, this cultivar did not differ from 'Red Frizzly no. 1'. The factor ground cover was not found to affect the characteristics evaluated, and therefore, cultivation without ground cover is recommended. The spacing 20 × 15 cm was shown to be favorable, resulting in cultivation with the highest populations, thereby increasing productivity. Based on the results obtained and for the conditions in which the experiment was conducted, it can be concluded that: planting time 3 (January 20, 2005) was the most favorable; the cultivars 'Red Frizzly no. 2' and 'Red Frizzly no. 1' are adapted to all the planting times; and cultivation without ground cover using a spacing of 20 × 15 cm was the most suitable.

Fertilizing lychee plants with phosphorus at time of planting in Brazil

The objective of this research was to study the effects of P fertilizers applied at time of planting on lychees' nutritional status and on plant growth. The treatments consisted of five doses of P: zero, 50, 100, 200, and 300 g of P2O5 per plant, furnished by triple superphosphate. Plant diameter was evaluated during two years and the plants' nutritional status on the second year. The second year foliar levels of macro and micronutrients (with the exception of Zn) were increased by the P fertilizer. The orchard's initial development, especially during the second year, was also influenced by the fertilizer. The P doses of 164 and 158 g of P2O5 per plant resulted in the largest plant diameter after the first and the second year, respectively. These doses were found to be associated with a foliar P level of <1.4 g kg-1. © 2012 Renato de Mello Prado et al.