Phenological and physiological evaluation of first and second cropping periods of sorghum and maize crops     

Maria Antonia Machado Barbosa  Kacilda Naomi Kuki  Pedro Santos Peno Bengala  Emilly dos Santos Pereira  Angélica Fátima de Barros  Sebastián Giraldo Montoya  Leonardo Duarte Pimentel 《Journal of Agronomy and Crop Science》2020,206(2):263-276

Environmental conditions influence phenology and physiological processes of plants. It is common for maize and sorghum to be sown at two different periods: the first cropping (spring/summer) and the second cropping (autumn/winter). The phenological cycle of these crops varies greatly according to the planting season, and it is necessary to characterize the growth and development to facilitate the selection of the species best adapted to the environment. The aim of this study was to characterize phenological phases and physiological parameters in sorghum and maize plants as a function of environmental conditions from the first cropping and second cropping periods. Two parallel experiments were conducted with both crops. The phenological characterization was based on growth analyses (plant height, leaf area and photoassimilate partitioning) and gas exchange evaluations (net assimilation rate, stomatal conductance, transpiration and water-use efficiency). It was found that the vegetative stage (VS) for sorghum and maize plants was 7 and 21 days, respectively, longer when cultivated during the second cropping. In the first cropping, the plants were taller than in the second cropping, regardless of the crop. The stomatal conductance of sorghum plants fluctuated in the second cropping during the development period, while maize plants showed decreasing linear behaviour. Water-use efficiency in sorghum plants was higher during the second cropping compared with the first cropping. In maize plants, in the second cropping, the water-use efficiency showed a slight variation in relation to the first cropping. It was concluded that the environmental conditions as degree-days, temperature, photoperiod and pluvial precipitation influence the phenology and physiology of both crops during the first and the second cropping periods, specifically cycle duration, plant height, leaf area, net assimilation rate, stomatal conductance and water-use efficiency, indicating that both crops respond differentially to environmental changes during the growing season.  相似文献   

Actinobacillus (Haemophilus) pleuropneumoniae Symposium   总被引：1，自引：0，他引：1       下载免费PDF全文

Lynch JA  Larivière S 《The Canadian veterinary journal. La revue veterinaire canadienne》1988,29(7):571

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International development: A new beginning          下载免费PDF全文

Julian D  Mills M  Carrière S  Stevenson B 《The Canadian veterinary journal. La revue veterinaire canadienne》1988,29(12):966-967

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Evaluation of a Killed Vaccine Against Porcine Pleuropneumonia Due to Haemophilus pleuropneumoniae   总被引：20，自引：2，他引：18  

Higgins R  Larivière S  Mittal KR  Martineau GP  Rousseau P  Cameron J 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(2):86-89

A bacterin containing serotypes 1 and 5 of Haemophilus pleuropneumoniae was developed for the prevention and the control of porcine pleuropneumonia. It was injected intramuscularly into three groups of ten piglets, the first group with one dose, the second one with two doses and the third one with three doses at two-week intervals. Another group of ten piglets did not receive the vaccine. All the piglets were then challenged by an aerosol of mixed suspensions of H. pleuropneumoniae serotypes 1 and 5. Two and three injections of vaccine completely prevented mortality, whereas half of the control piglets and of those receiving only one dose of vaccine died. All surviving piglets, both control and vaccinated, had severe signs of respiratory disease for at least 36 hours after exposure to challenge. Moreover, vaccination did not induce the production of antibodies at high titers. Local reactions were not noted after vaccination and at postmortem; ten weeks after the challenge, there were no signs of abscess formation or induration.  相似文献   

A syndrome of dental abnormalities of sheep: I. Clinical aspects on a commercial sheep farm in the Wairarapa.     

A N Bruère  D M West  M B Orr  M W O'Callaghan 《New Zealand veterinary journal》1979,27(8):152-158

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The significance of the XO syndrome in infertility of the mare.     

M G Blue  A N Bruère  H F Dewes 《New Zealand veterinary journal》1978,26(6):137-141

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Preliminary observations on the occurrence of the equine XO syndrome.     

A N Bruère  M G Blue  P M Jaine  K S Walker  L M Henderson  H M Chapman 《New Zealand veterinary journal》1978,26(6):145-146

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Escherichia coli strains isolated from diarrheic piglets in the Province of Quebec.          下载免费PDF全文

S Larivière  R Lallier 《Canadian journal of veterinary research》1976,40(2):190-197

During 1972 to 1974, 112 Escherichia coli strains isolated from diarrheic piglets were recieved from different parts of the Province of Quebec, Canada. Fifty-six strains elicited a positive gut loop response in three week old piglets and were then considered as Moon's class 1 enteropathogens, while four of the 56 remaining strains reacted only in ten day old piglets and were classified as class 2 enteropathogens. Forty-eight strains produced both a heat-labile and a heat-stable enterotoxin, while 12 isolates which included the four class 2 enteropathogens produced only a heat-stable enterotoxin. Fifty-one enterotoxigenic strains could be serogrouped using OK antisera against E. coli strains commonly associated with colibacillosis in piglets. The most common serogroups encountered were O157: K "V17"; 88a,c, O149:K91; 88a.c. O157:K"V1c, O149:K91; 88a.c, O157:K"V17"; 88 a,c or a,b and O45:K"E5"; 88a,c. No significant difference was observed in the fermentation patterns, antibiotic susceptibility, colicin production, production of a filterable hemolysin and transferable tetracycline resistance between the enterotoxigenic and the nonenterotoxigenic strains.  相似文献   

Electrocorticogram disturbances detected in rats exposed from early stages of life to residual doses of lindane     

P. Breton  I. Delamanche  F. Goudey Perrière 《Pesticide biochemistry and physiology》2005,81(2):97-104

Functional brain alterations induced by lindane were examined in Rat chronically exposed to low doses of lindane (1 and 2 μg L⁻¹ in drinking water) from conception. Histological and electrophysiological investigations were conducted at 14 weeks of age. Lindane did not induce histological changes. It did not significantly modify the sleep-wakefulness cycle and EEG did not show major alterations. The spectral EEG analysis, by recording cortical variations in both energy spectrum and energy levels of different frequency bands, showed an increase in the 11-15 Hz activity in both groups exposed to lindane. This activity was characterised by spindles well-depicted during slow wave sleep or associated with fast activity during wakefulness and theta activity in paradoxical sleep. These data suggest that chronic exposure to lindane doses as low as 1 μg L⁻¹ in drinking water could lead to central electrophysiological effects possibly involving GABA-benzodiazepine mechanisms.  相似文献   

Effects of surgical implantation of temperature dataloggers on reproduction of captive striped skunks (Mephitis mephitis).     

Yeen Ten Hwang  Marie-Line Gentes  Dennilyn L Parker  Serge Larivière  Fran?ois Messier 《Journal of zoo and wildlife medicine》2004,35(4):515-519

A total of 20 (14 females, six males) captive striped skunks (Mephitis mephitis) with miniature temperature dataloggers implanted free in the abdominal cavity were examined for reproductive performance and pathology because of implants. Eleven of 12 female skunks reproduced successfully 45.9+/-3.7 days after surgery to remove implanted dataloggers. The pregnancy rate of 91.7% (11/12) was much higher than other captive studies and was comparable with that of wild skunks. Eight striped skunks (six males, two females) that were euthanatized and necropsied after having implants in the abdominal cavity for 5 mo showed no apparent pathology associated with the implant. Implantation of the intraperitoneal devices did not lead to complications in abdominal tissues. Neither implant nor surgery affected reproduction. We conclude that implanted dataloggers can safely be used in physiologic studies of striped skunks or possibly other small carnivores in captive or field studies.  相似文献