Tolerance of cucumber crop to salinity in greenhouse

Neste trabalho se objetivou avaliar a cultura do pepino conduzido sobre condição salina, proveniente de sais fertilizantes, com seis níveis de salinidade do solo (1,5; 2,5; 3,5; 4,5; 5,5 e 6,5 dS m-1). O experimento foi conduzido na área experimental do Departamento de Engenharia Rural da ESALQ/USP, Piracicaba, SP. O plantio foi realizado em vasos utilizando-se solo arenoso. A época de plantio foi de 28/08/07 a 20/10/07. Como principais resultados, verificou-se que a produtividade máxima obtida foi 2,45 kg m-2 para o nível de salinidade 3,5 dS m-1; com os valores de produção relativa obteve-se a salinidade limiar (SL) de 4,08 dS m-1, com uma queda de produção, após o ponto limiar na ordem de 19,33% por dS m-1, para cada aumento de uma unidade de salinidade do solo.The objective of this work was to evaluate the cucumber crop in saline conditions resulting from fertilizer salt, under six levels of soil salinity (1.5, 2.5, 3.5, 4.5, 5.5 and 6.5 dS m-1). The study was carried out in the experimental area of the Department of Rural Engineering of the ESALQ/USP, Piracicaba/SP, Brazil. The planting was carried out in recipients using sandy soil during the period of 28/08/07 to 20/10/07. As the main results, it was verified that the maximum productivity was 2.45 kg m-2 for the salinity level of 3.5 dS m-1, that with the values of relative production the threshold salinity (SL) observed was of 4.08 dS m-1, and that there was a decline of 19.33% in production for unit increase of soil salinity above the threshold point

Surface albedo from Landsat 5 images in areas of sugar cane and cerrado

Propôs-se, neste trabalho, estimar dados de albedo à superfície terrestre usando-se o sensor Thematic Mapper (TM) do satélite LANDSAT 5 e compará-lo com dados de duas estações agrometeorológicas localizadas em região de Cerrado e a outra em cultivo da cana-de-açúcar. A região de estudo está localizada no município de Santa Rita do Passa Quatro, SP, Brasil. Para a realização do estudo obtiveram-se seis imagens orbitais do satélite Landsat 5 sensores TM, na órbita 220 e ponto 75, nas datas de 22/02, 11/04, 29/05, 01/08, 17/08 e 21/11, todas do ano de 2005, a que correspondem os dias juliano de 53, 101, 149, 213, 229 e 325, respectivamente. As correções geométricas para as imagens foram realizadas e geradas as cartas de albedo. O algoritmo SEBAL estimou satisfatoriamente os valores de albedo de superfícies sobre áreas de cerrado e de cana-de-açúcar, na região de Santa Rita do Passa Quatro, SP, consistentes com observações realizadas do albedo à superfície.This study aimed to estimate albedo data from the land surface sensor using the images of Thematic Mapper (TM) satellite LANDSAT 5 and to compare it with data from two agrometeorological stations located in the region of Cerrado, and another in sugar cane cultivation. The study area is located in the municipality of Santa Rita do Passa Quatro - SP, Brazil. To carry out the study six orbital images were obtained from the satellite Landsat 5 TM sensors in the orbit 220 and in the section 75, for the dates of 22/02, 11/04, 29/05, 01/08, 17/08 and 21/11 (all in the year of 2005) which correspond to the days 53, 101, 149, 213, 229 and 325, respectively. The geometric correction for images was performed and the letters of albedo were generated. The algorithm SEBAL estimated, satisfactorily, the values of albedo on the surface areas of Cerrado and sugar cane in the region of Santa Rita do Passa Quatro - SP, consistent with observations made of the surface albedo

Genomic structure and marker-derived gene networks for growth and meat quality traits of Brazilian Nelore beef cattle

Abstract\ud \ud Background\ud Nelore is the major beef cattle breed in Brazil with more than 130 million heads. Genome-wide association studies (GWAS) are often used to associate markers and genomic regions to growth and meat quality traits that can be used to assist selection programs. An alternative methodology to traditional GWAS that involves the construction of gene network interactions, derived from results of several GWAS is the AWM (Association Weight Matrices)/PCIT (Partial Correlation and Information Theory). With the aim of evaluating the genetic architecture of Brazilian Nelore cattle, we used high-density SNP genotyping data (~770,000 SNP) from 780 Nelore animals comprising 34 half-sibling families derived from highly disseminated and unrelated sires from across Brazil. The AWM/PCIT methodology was employed to evaluate the genes that participate in a series of eight phenotypes related to growth and meat quality obtained from this Nelore sample.\ud \ud \ud Results\ud Our results indicate a lack of structuring between the individuals studied since principal component analyses were not able to differentiate families by its sires or by its ancestral lineages. The application of the AWM/PCIT methodology revealed a trio of transcription factors (comprising VDR, LHX9 and ZEB1) which in combination connected 66 genes through 359 edges and whose biological functions were inspected, some revealing to participate in biological growth processes in literature searches.\ud \ud \ud Conclusions\ud The diversity of the Nelore sample studied is not high enough to differentiate among families neither by sires nor by using the available ancestral lineage information. The gene networks constructed from the AWM/PCIT methodology were a useful alternative in characterizing genes and gene networks that were allegedly influential in growth and meat quality traits in Nelore cattle.This study was conducted with funding from EMBRAPA (Macroprograma1,\ud 01/2005) and FAPESP (process number 2012/23638-8). GBM, LLC, LCAR and\ud MMA were granted CNPq fellowships. We thank Sean McWilliam, Marina R. S.\ud Fortes, Edilson Guimaraes, Robson Rodrigues Santiago, Roselito F. da Silva,\ud Fernando F. Cardoso, Flavia Aline Bressani, Wilson Malago Jr., Avelardo U. C.\ud Ferreira, Michel E. B. Yamaguishi and Fabio D. Vieira for the help and\ud technical assistance. The authors would like to acknowledge the\ud collaborative efforts among EMBRAPA, University of Sao Paulo and CSIRO