Editora

UGUR, Atnan  e  MADEN, Hande Ayhan. SOWING AND PLANTING PERIOD ON YIELD AND EAR QUALITY OF SWEET CORN (Zea mays L. var.saccharata). Ciênc. agrotec. [online]. 2015, vol.39, n.1, pp. 48-57. ISSN 1413-7054.  http://dx.doi.org/10.1590/S1413-70542015000100006.

ABSTRACT

Sweet corn (Zea mays L. var. saccharata) attracts people with its amazing flavour. Adverse environmental factors decrease plant’s cob yield and quality. A more effective production can be made by using resistant varieties and adjusting the sowing and plating periods. In this study, the effect of direct seed sowing and cultivating with seedlings in three different times (5, 15 and 25 May) on the sweet corn’s cob yield and certain quality features have been investigated. In the Continue reading

LIMA, Juliana Joice Pereira et al. ACCELERATED AGING AND ELECTRICAL CONDUCTIVITY TESTS IN CRAMBE SEEDS. Ciênc. agrotec. [online]. 2015, vol.39, n.1, pp. 7-14. ISSN 1413-7054.  http://dx.doi.org/10.1590/S1413-70542015000100001.

ABSTRACT

The aim of this study was to adapt the methodology of the accelerated aging and electrical conductivity tests for determination of physiological potential in crambe seeds. Six seed lots of crambe (cv. FMS Brilhante) were subjected to determination of moisture content, germination test, first count germination, emergence, and emergence speed index. For the accelerated aging test, the traditional methodology was used with water, and with a saturated potassium chloride and sodium chloride

Continue reading

ABSTRACT

ABREU, José Renato de et al. IDENTIFICATION AND QUANTIFICATION OF DIFFERENTIALLY EXPRESSED GENES ASSOCIATED WITH CITRUS BLIGHT (Citrus spp.). Ciênc. agrotec. [online]. 2015, vol.39, n.1, pp. 32-38. ISSN 1413-7054.  http://dx.doi.org/10.1590/S1413-70542015000100004.

Brazil is the largest citrus producer in the world, being responsible for more than 20% of its production, which is, however still low due to phytosanitary issues such as citrus blight. Citrus blight is an anomaly whose causes still have not yet been determined, therefore there are no efficient control measures to minimize the production losses with the use of resistant varieties being considered the most appropriate method. However, little is known about the genes involved in the defense response of the plants to this anomaly. Considering that many physiological alterations associated with plant stress responses are controlled at a transcriptional level, in this study we sought the identification and characterization of the gene expression products differentially expressed in the response to the citrus blight. Through the suppressive subtractive hybridization technique, expressed cDNA libraries were built using mRNAs isolated from “Cravo” lemon tree roots (Citrus limonia L. Osbeck) under “Pera” Continue reading

ABSTRACT

Stress is one of the major obstacles in frog culture and can be caused by factors such as inappropriate farming systems; inadequate management among other situations. The objective of the present study was to assess the hemogram, erythrogram and leukogram of bullfrogs (L. catesbeianus) when exposed to stress caused by different types of management: density and handling (manipulation), developed in the laboratory and repeated in the field for the appropriate comparisons in a experimental period of 30 days. The density experiment was conducted with four treatments: 70 animals m^-2 (D70); 100 animals m^-2 (D100), Control; 150 animals m^-2 (D150) and 200 animals m^-2 (D200), with 10, 14, 21 and 28 animals/box in the laboratory, respectively. Each treatment was performed with three simultaneous replicates. The handling experiment was conducted with three treatments: Treatment Without Handling (WH); Treatment with Partial Handling (PH) every 15 days and Treatment with Total Handling (TH) every 15 days. Each treatment was performed with four simultaneous replications. The methodology of the blood analysis followed international recommendations. In the present study we could observe that the animals of the field experiment did not reflect the same stress response observed in the laboratory in both experiment, which demonstrated the plasticity of these animals.

Key words: L. catesbeianus; density; handling; physiological response; hematology

TEIXEIRA, Patrícia Coelho et al. BULLFROG HEMOGRAM UNDER MANAGEMENT STRESS. Ciênc. agrotec. [online]. 2015, vol.39, n.2, pp. 154-163. ISSN 1413-7054.  http://dx.doi.org/10.1590/S1413-70542015000200007.

Abstract

OLIVETTI, Diogo et al. SPATIAL AND TEMPORAL MODELING OF WATER EROSION IN DYSTROPHIC RED LATOSOL (OXISOL) USED FOR FARMING AND CATTLE RAISING ACTIVITIES IN A SUB-BASIN IN THE SOUTH OF MINAS GERAIS. Ciênc. agrotec. [online]. 2015, vol.39, n.1, pp. 58-67. ISSN 1413-7054.  http://dx.doi.org/10.1590/S1413-70542015000100007.

Water erosion is one of the most important soil degradation processes and it can be intensified by land use and vegetal covering changes. Thus, water erosion modeling studies associated to multi temporal analyses of land use are effective in assessing how changes in land cover affects sediment yield. Therefore, considering the modifications in the land use from 1986 to 2011, the aim of this study ranged to estimate water erosion rates and compare them to the soil loss tolerance (SLT) limit in the Latosols (Oxisols) at Ribeirão Caçús sub-basin, in the South of Minas Gerais State, Southeast Brazil, by means of the Revised Universal Soil Loss Equation (RUSLE) in association with the geographic information system (GIS), and geostatistical techniques. So, for each year mapped, soil loss averages were compared by t test at 5% significance to assess the soil degradation stage. The results indicated that, in the period, the soil loss average rate was from 2.4 to 2.6 Mg ha-1 year-1 and the areas with soil loss above the limit of SLT were around 8.0%. The t test demonstrated there was no considerable difference among the soil loss averages (p = 0.18). In consequence, the area of degraded soils did not increase. Thus, the RUSLE model in GIS is a simple and useful tool to estimate the soil loss and help define soil conservation and recovery measures.

Palavras-chave : Land use changes; RUSLE; soil loss prediction; soil degradation.