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E Silva O.A.B.N.,University of Sao Paulo | Botton M.,Pesquisador Embrapa Uva e Vinho | Garcia M.S.,FAEM UFPel | da Silva A.,FAEM UFPel
Revista Brasileira de Fruticultura | Year: 2011

The objective of this study were to evaluate the effect of insecticides insect growth regulators (IGR's) on eggs, larvae and adults of G. molesta, in the laboratory. The evaluated insecticides were Lufenuron and Novaluron (4.0g of a.i. 100L-1), Methoxyfenozide and Tebufenozide (9.6g of a.i. 100L-1) and control (distilled water). In application before oviposition, only Methoxyfenozide caused significant mortality of eggs (26.3%) compared to control. The application of insecticides on eggs of different ages (24, 48 and 72 hours) showed variations in mortality of the species regarding the insecticide and time of embryonic development. Only Methoxyfenozide and Novaluron reduced the viability of larvae that emerged from treated eggs, with a maximum of 35.9% and 39.5 of larval viability when applied on eggs of 48-72 hours, respectively. The treatment of apple fruit with insecticides caused significant mortality of larvae, but no differences were observed among insecticides, both for small larvae (average efficiency of 47.2%) and for 3rd -4th instar larvae (averaging 45.3%). Lufenuron reduced its efficacy on 3rd-4th instar larvae. The ingestion of Lufenuron, Methoxyfenozide, Novaluron and Tebufenozide by adults of G. molesta reduced fecundity and fertility, however the adult longevity was only negatively affected by the ingestion of Methoxyfenozide and Tebufenozide.

Leite L.F.C.,Embrapa Meio Norte | Galvao S.R.S.,Embrapa Meio Norte | Neto M.R.H.,FAEM UFPel | Araujo F.S.,University of Campinas | Iwata B.F.,Campus Universitario Ministro Petronio Portella
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2010

No-tillage adoption has been considered a viable alternative for sustainable soil use. This work aimed to evaluate the influence of no-tillage system with different times of adoption and conventional tillage on chemical attributes and carbon stocks in an Oxisol of the savannah of Piauí in Northeastern Brazil. Soil samples in the 0-5, 5-10, 10-20 and 20-40 cm layers were collected in conventional tillage (CT) no-tillage (NT) with 2 (NT2), 4 (NT4) and 6 (NT6) years of adoption and native forest (NF). The following chemical properties were evaluated: pH, extractable P, exchangeable cations, Al, potential acidity (H+Al), total organic carbon (TOC) and microbial biomass carbon (Cmic). NT adoption increased pH, extractable P and exchangeable cations contents. Compared to conventional tillage, TOC and Cmic stocks increased 34 and 99% (NT2), 47 and 92% (NT4) and 61 and 108% (NT6), respectively, in the superficial layer (0-20 cm). No-tillage adoption improves chemical attributes and increases total organic carbon and microbial carbon and its continuous use contributes to soil quality in savannah soils of Piaui state.

The Mediterranean fruit fly Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is one of the principal exotic pests affecting Brazilian production in the northeastern and southeastern regions of Brazil. In the south, it is has potential as a serious threat to temperate-climate fruit farms, since it is already found in urban and suburban communities in this region. We studied the biological characteristics of C. capitata populations from Pelotas-RS (temperate climate), Petrolina-PE (tropical), and Campinas-SP (subtropical). Ceratitis capitata biology was studied under controlled temperature (15, 20, 25, 30, and 35 ± 1 °C), 70 ± 10% RH, and 14:10 L:D photoperiod. The duration and survival rate of the egg, larval, and pupal stages were evaluated and the thermal requirements of these three populations were determined. The duration and survival of these developmental stages varied with temperature, with similar values for the three populations, except for some variation in the egg phase. Egg to adult developmental time for all three populations was inversely proportional to temperature; from 15 to 30 °C developmental time varied from 71.2 to 17.1, 70.2 to 17.1, and 68.5 to 16.9 days, respectively. Survival during development was affected at 15 to 30 °C, and differed significantly from survival at 20 to 25 °C. At 35 °C, immature stages did not develop. The basal temperature and degree-day requirement were similar for all immature stages except for the egg stage. The basal temperatures and thermal constants were 9.30 and 350, 8.47 and 341, and 9.60 °C and 328 degree-days for the Pelotas, Petrolina, and Campinas populations, respectively. Results suggested that survival and thermal requirements are similar for these tropical, subtropical, and temperate populations of C. capitata, and demonstrate the species' capacity to adapt to different climate conditions.

The study aimed to evaluate the incidence of biological and physiological disorders in the field and postharvested apples cvs. Gala, Fuji and Catarina grown in four production systems: conventional, organic transition, integrated and organic. Apples were evaluated for damages related to biological and physiological disorders in the orchard and after harvest. The greatest damages were attributed to pests, especially Anastrepha fraterculus in the organic system and Grapholita molesta in the organic transition. Apples produced in organic orchards had higher damage levels caused by postharvest physiological disorders than those grown in other production systems. For apples becoming from organic orchards most of the damage was due to lenticels breakdown and degeneration ('Gala'), and bitter pit ('Fuji' and 'Catarina'). The incidence of postharvest rot was not influenced by apple production system.

Harter F.S.,FAEM UFPel | Barros A.C.S.A.,FAEM UFPel
Revista Brasileira de Sementes | Year: 2011

The use of natural products in plant protection constitutes an important tool for the farmers to organic production. The study aimed to evaluate the efficiency of the calcium and silicon in the production and quality of soybean seeds. We used seeds of organic soybeans (Glycine max L.) cultivar BR36, from such cooperative in the 2004/2005 harvest. The experimental design used was randomized blocks with five treatments (calcium 40, calcium 50, silicon 40, silicon 50 and control). The treatments were compared by Duncan test at 5% probability. The variables of yield components were: number of pods per plant, seed number per pod, productivity and yield. The physiological quality of seeds was determined by tests: germination, first count germination, cold test, electrical conductivity and accelerated aging. Conclude that soybean plants treated with calcium and silicon produce seeds of higher physiological quality; treatments with application of Ca and Si reduce the seed yield per unit area.

Lauxen L.R.,UFPel FAEM | Villela F.A.,FAEM UFPel | Soares R.C.,UFPel FAEM
Revista Brasileira de Sementes | Year: 2010

The introduction of new seed treatment products is increasing and bioactivators, such as the insecticide thiametoxam, are used to increase plant yield potential by modifying metabolism. The objective of this study was to evaluate the effects of thiametoxam on the physiological quality of cotton seeds, particularly on seedling root growth, and establish product concentrations for seed pre-treatment. Three seed lots of the cultivar CD 408 were evaluated which had been treated with six dosages of Cruiser® 350 FS containing 35 g/L A.I. of thiametoxam, at 0, 2, 4, 6, 8 and 10 mL per kg of seeds. Parameters measured included: standard germination test, germination first count, accelerated ageing, root dry matter and length, emergence velocity rate and final seedling emergence. Cotton seeds treated with thiametoxam demonstrated improved physiological quality of the seeds and the dosages of 5.0 to 7.0 mL of the Cruiser® 350 FS/kg of seeds were more efficient in improving the physiological performance of cotton seeds.

Funguetto C.I.,Federal University of Pampa | Pinto J.F.,FAEM UFPel | Baudet L.,FAEM UFPel | Peske S.T.,FAEM UFPel
Revista Brasileira de Sementes | Year: 2010

The rice cultivation is a major cereal that has a high response to the application of zinc, with culture more sensitive to deficiency of this element. The objective in this study was to evaluate the effects of coatings of different doses of zinc in seeds of rice, on the performance of seeds and the yield components. The work was conducted at the Federal University of Pelotas in the agricultural year of 2006/07. The treatments consisted of applying a mixture of zinc sulphate heptahydrate (22% Zn), with six levels: zero; 0,37; 0,47; 0,57; 0,67 and 0,77 g kg-1 seed. In addition to coating with zinc sulphate, was used for all treatments a mixture of fungicide (3 mLkg-1), polymer CF Clear® (200 mg kg-1) and dye (4 mL kg-1). The experimental design was completely randomized with four replications. Seed quality was evaluated by means of the germination test and tests of force (length of shoot and root, biomass of shoots and roots of seedlings). In a greenhouse were evaluated further the components of yield (number of panicles per plant, number of grains per panicle and grain weight per plant). Based on the results it was obtained the following conclusions: 1 - The coating of rice seeds with zinc, the dosage of 0,77 g kg-1 seed, increases the number of grains per panicle and weight of grains per plant under conditions of a greenhouse. 2 - Seed of rice covered with zinc generating plants with higher growth. 3 - The coating with zinc does not affect the germination.

da Silva K.R.G.,FAEM UFPel | Villela F.A.,Brazilian National Council for Scientific and Technological Development
Revista Brasileira de Sementes | Year: 2011

Soybean seeds submitted to rapid hydration may be damaged by imbibitions with the intensity depending on the seed cultivar and initial moisture content. The present study evaluated physiological changes measured by pre-hydration methods to minimize damage by imbibition. Three lots of each soybean cultivar, CD 202 and CD 215, of uniform size, were evaluated for their moisture content, germination, germination first count, accelerated aging, electrical conductivity and seedling emergence in the field. The moisture contents of seeds were adjusted to 7.5, 10.5 and 13.5%. The seeds were pre-hydrated in a saturated atmosphere and moist substrate for four to six hours and then evaluated for electrical conductivity after 24 hours, and also for germination and field seedling emergence. Pre-hydration treatments in a saturated atmosphere and on a moist substrate for four to six hours effectively reduced damage to seeds with a low moisture content, especially for the CD 202 cultivar. However, pre-hydration on a moist substrate for six hours was more efficient for both genotypes, with fewer solutes leached, and confirmed by a lower value observed for the electrical conductivity test. This resulted in an improved performance in germination tests and seedling emergence in the field.

Holbig L.S.,FAEM UFPel | Baudet L.,FAEM UFPel | Villela F.A.,FAEM UFPel | Cavalheiro V.,Brazilian National Council for Scientific and Technological Development
Revista Brasileira de Sementes | Year: 2010

Vegetable production plays a major socio-economic role because it is labor intensive. The objective of this study was to evaluate the physiological performance of carrot seed after priming (osmotic preconditioning), fungicide treatment and polymer film coating. Carrot seeds cv. Brazlândia were provided by Hortec, Bagé / RS and submitted to priming with an aerated solution of polyethylene glycol (PEG 6000) at - 0.8 MPA for 10 hours. Seeds were then rinsed with distilled water and oven dried until moisture content was 7%. The seeds were treated with Captan 750 TS® (750g a.i.) fungicide at a dosage of 0.2% and coated with the polymer Colorseed® at a dosage of 50 Seed treatments were: no osmoconditioning (NCOND), with osmoconditioning (COND), no polymer (SP), with polymer (CP), no fungicide (SF) and with fungicide (CF), making up the following combinations: 1) NCOND SP SF, 2) NCOND CP SF, 3) NCOND SP CF, 4) NCOND CP CF, 5) COND SP SF, 6) COND CP SF, 7) COND SP CF e 8) COND SP CF. Seed quality was evaluated using the following tests: germination, cold, modified accelerated aging, greenhouse emergence, germination and emergence velocity index, seedling length, seedling dry and fresh matter weight. The statistical design was completely randomized in a 2 (primed and not-primed seeds) × 4 (treatments with fungicide and polymer) factorial, with four replications. Averages were compared by the Duncan test at the 5% significance level. Osmoconditioning increases the speed of germination and seedling emergence; the application of polymer and fungicide on osmoconditioned carrot seed did not affect seedling vigor and regardless of the coating and/or fungicide treatment, the osmoconditioned seeds performed better.

Fachinello J.C.,FAEM UFPel | de Franceschi E.,Brazilian National Council for Scientific and Technological Development
Revista Brasileira de Fruticultura | Year: 2012

Pears are the most imported fruit in Brazil, thus its cultivation may represent an important opportunity to Brazilian growers. however, there are still some problems that restrict pear production, such as the lack of adapted rootstocks. The aims of this study were to assess growth, yield and fruit quality of two pear cultivars: Carrick grafted on quinces 'Portugal', 'MC', 'BA29', 'D'vranja' and 'inta 267' and Packham's Triumph grafted on 'Adam's', 'D'Angers', 'Alongado', 'Smyrna' and Pyrus calleryana. in a completely randomized block design, with 3 replicates per treatment, a 2-year (2009-10) experiment was carried out in a 7-year old pear orchard, trained on central leader, at 1.0x5.0 m spacing, at the Centro Agropecuário da Palma, FAEM/UFPel. The assessed parameters were trunk cross sectional area, yield efficiency, yield, cumulative yield, fruit number per tree, total soluble solids, flesh firmness, fruit weight and fruit diameter. The yield of 'Carrick' and 'Packham's Triumph' was increased when quince rootstocks 'Portugal' and 'MC'; 'Adams' and 'D'Angers' were adopted, respectively. Moreover, it was found that yield and yield efficiency of both cultivars generally was inversely proportional to the vigor induced by the rootstock. Fruits of 'Carrick' and 'Packham's Triumph' cultivars accumulated higher amounts of soluble solids when grafted on dwarfing rootstocks.

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