Effects on soil chemical attributes and cotton yield from ammonium sulfate and cover crops

Fertilizer use in no-till systems must be aligned with a correct interpretation of soil chemical attributes and crop demands. The objectives of this work were evaluate the effects of pre-sowing application of ammonium sulfate (AS) and of cover crops on the yields and soil chemical attributes of no-till cotton (Gossypium hirsutum L. r. latifolium Hutch) over two harvesting years. The experiment was arranged in randomized complete block design, with the plots in strips, and the variables were three cover crops (Raphanus sativus L., Avena strigosa L. and Avena sativa L.) and four AS doses (0, 150, 300, and 450 kg ha-1) applied over millet dry biomass. The cotton in the experimental plots was manually harvested on April 25, 2007 and April 24, 2008. The soil samples were collected between cotton rows in all plots on May 5, 2007 and May 12, 2008, at depths of 0.0-0.05, 0.05-0.10, and 0.10-0.20 m for soil fertility analyses. The increasing doses of AS induced lower soil pH, and calcium (Ca) and magnesium (Mg) levels in the superficial soil layer, as well as higher exchangeable aluminum (Al) and sulfur (S) levels until a depth of 0.20 m. Seed cotton yields increased with increasing AS doses.

Leaf gas exchange and yield of three upland rice cultivars

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Reproduction of Meloidogyne enterolobii in lettuce cultivars of the american group

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Agronomic efficiency and grain quality of upland rice cultivars as a function of nitrogen topdressing

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Plant density in production of mini lettuce cultivars in organic system management

Production of mini vegetables in organic system is a good alternative to improve profit, but there are no researches about the optimum plant density for these cultivars in Brazilian conditions. Two experiments were conducted to evaluate the production of mini lettuce cultivars in different plant densities. Experiment 1 was conducted from January 1th (sowing) to February 10th (harvesting), 2012. The experimental design was completely randomized blocks, with six treatments in factorial scheme, 3 mini lettuce cultivars (Tudela, Renoir and Sartre) x 2 spacing between plants (16 and 20 cm), with eight replications and plots (2.04 m(2)) with six rows, spaced 15 cm. Experiment 2 was conducted from June 6th (sowing) to July 18th (harvesting), 2012. The cultivars Sartre and Renoir were evaluated under four plant densities (444,444; 333,333; 266,667 and 200,000 plants ha(-1), corresponding to spacing of 15x15, 15x20, 25x15 and 25x20 cm, respectively). Eight treatments were defined by a factorial scheme 2 (cultivars) x 4 (plant densities) and arranged in a completely randomized block design, with nine replications and plots with 2.04 m2. The evaluated characteristics in both experiments were total and marketable fresh weight per plant, plant dry weight, plant diameter and height, marketable yield and discard percentage. In first experiment, during the summer, cultivar Sartre showed the highest marketable fresh weight (72 g plant(-1)). Heaviest plants (91.6 g plant(-1)) were obtained with the higher plant spacing, but the highest yield (2.51 kg m(-2)) was obtained with the smaller spacing. In winter, plants with higher total (190 g plant(-1)) and marketable (146 g planta(-1)) fresh weight were obtained with cultivar Sartre, and the same was observed in low plant density. However, the higher plant density, the higher the yield.

Physicochemical and structural characteristics of rice starch modified by irradiation

This work evaluated the physicochemical and structural properties of rice starch of the cultivars IAC 202 and IRGA 417 modified by irradiation. Starch samples were irradiated by (60)Co in doses 1, 2 and 5kGy, on a rate of 0.4kGy/h. A control not irradiated was used for comparison. The granule morphology and A-type X-ray diffraction pattern were not altered by irradiation. There was an increase in amylose content, carboxyl content and acidity with irradiation. Gamma radiation did not affect the thermal properties of IAC202, but increased gelatinization temperature of IRGA417, in the higher dose (5kGy). The number of long chains of amylopectin was reduced and short chains were increased for IAC202, whereas for IRGA 417, the opposite was observed, probably due to cross-linking of starch chains. Starches had their physicochemical and structural properties modified by irradiation differently.

Processo de produção de composto orgânico derivado de resíduos industriais com aplicação no cultivo de alface

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito alelopático de melissa, capim-cidreira, lavanda e alecrim na germinação e vigor de sementes de alface

Objetivou-se, neste estudo, avaliar a inluência na germinação e vigor de sementes de alface (Lactuca sativa L.) de macerados e infusões de Melissa oficinalis L. (melissa), Rosmarinus oficinalis L. (alecrim), Lavandula angustifolia Mill. (lavanda) e Cymbopogon citratus (DC.) Stapf. (capim-cidreira). O delineamento estatístico utilizado foi inteiramente casualizado, com nove tratamentos e quatro repetições, cada unidade experimental constituída por 25 sementes. Sendo os tratamentos: alecrim infusão, alecrim macerado, lavanda infusão, lavanda macerado, melissa infusão, melissa macerado, capim-cidreira infusão, capim-cidreira macerado e testemunha. As variáveis avaliadas foram: índice de velocidade de germinação (IVG), porcentagens de plantas anormais (PA), porcentagens de plantas germinadas (PG), massa fresca (MF), massa seca (MS), comprimento da parte aérea (CPA) e comprimento da radícula (CR). O capim-cidreira apresentou efeito alelopático negativo na germinação e no vigor de sementes de L. sativa L. Já em melissa infusão veriicou-se ação estimulante.

Acúmulo de nutrientes e resposta da alface à adubação fosfatada

Nutrient absorption and response of lettuce to phosphorus fertilization. The objective of this study was to evaluate the response of lettuce (cultivar Verônica) to different levels of phosphorus fertilization. The experiment was conducted from 25/09/2003 (sowing) to 03/12/2003 (harvesting) at the Fazenda Experimental São Manuel, UNESP/FCA, Botucatu/SP, under protective structures. The experiment was conducted in a randomized block design, with five treatments (0, 200, 400, 600 and 800kg.ha-1 of P2 O5, in the form of triple superphosphate) and five replications. Plants were grown in 13L plastic pots containing Latossolo Vermelho Distrófico Típico. A quadratic response was observed for the fresh mass of the plant shoots and leaf area, with maximum equivalent levels of 733 and 756kg.ha-1 of P2 O5 , respectively, as well as for potassium, calcium, magnesium, sulfur, boron, copper, iron, manganese and zinc accumulation. Linear increases were observed with the treatments of P2 O5 for dry mass of the shoots, leaf number, plant height and nitrogen and phosphorus accumulation.

Efeito de fungos contaminantes na produtividade de dois isolados de Agaricus blazei em duas formulações de composto

The effect of the contaminant fungi Trichoderma sp. and Chaetomium olivacearum on the cultivation of the ABL 99/30 and ABL 04/49 isolates of A. blazei in two compost formulations made up with tyfton (Cynodom dactylon) and oat (Avena sativa) was evaluated. The experimental design was a totally randomized 2 x 2 x 3 factorial design with 6 repetitions. The experimental unit consisted of 12-12.5 kg of wet compost. During the spawning, 150 g of Trichoderma sp. and C. olivacearum were added to the compost. The experiment was carried out in a climatized room, with humidity between 75-90% and temperature of 28º C. The productivity averages of the ABL 99/30 isolate of A. blazei were higher than those of ABL 04/49 and Trichoderma sp. and C. olivacearum negatively influenced the production of A. blazei. The different composts (based on tyfton and oat straw) did not influence the production of basidiomata.

Atividade da enzima nitrato redutase em cultivares de arroz de terras altas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Gamma irradiation can control the number of psychotrophic bacteria in Agaricus bisporus during storage

We evaluated the effect of gamma irradiation doses (0, 125, 250, and 500 Gy) in control of psychrotrophic bacteria in different strains of Agaricus bisporus (ABI-07/06, ABI-05/03, and PB-1) during storage, cultivated in composts based on oat straw (Avena sativa) and Brachiaria spp. The experimental design was completely randomized in a factorial scheme 4  2  3 (irradiation doses  composts  strains), with 24 treatments, each consisting of 2 replicates, totaling 48 experimental units (samples of mushrooms). The mushrooms collected from all culture conditions were packaged in plastic polypropylene with 200 g each and subjected to Cobalt-60 irradiator, type Gammacell 220, and dose rate 0.740 kGy h–1 , according to the treatments. Subsequently, the control (nonirradiated) and other treatments were maintained at 4 ± 1°C and 90% relative humidity (RH) in a climatic chamber to perform the microbiological analysis of mushrooms on the 1st and 14th day of storage. According to the results, it was found that the highest mean colony psychotrophic count, after 14 days of storage, was observed in strain ABI-07/06 1.30 × 108 g -1 most probable number (MPN) in nonirradiated mushrooms, coming from Brachiaria grass-based compost, and this same strain under the same storage conditions, coming from the same type of compost that underwent a dose of 500 Gy, obtained a significant reduction in mean colonies of psychrotrophic bacteria (2.25 × 104 g –1 MPN). Thus, the irradiation doses tested favored reducing the number of colonies of psychrotrophic bacteria, regardless of the type of compound and strain of A. bisporus.

Desempenho operacional de transplante manual e mecanizado da cultura da alface

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Monitoramento de raças de Bremia lactucae em alface no ano de 2014 e sua distribuição no Estado de São Paulo

Pós-graduação em Agronomia (Genética e Melhoramento de Plantas) - FCAV

Desempenho de genótipos de alface-crespa em diferentes ambientes de cultivo, no município de Igarapava - SP

Pós-graduação em Agronomia (Produção Vegetal) - FCAV