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11.
The plant defence activators acibenzolar-S-methyl (Benzo[1,2,3]thiadiazole-7-carbothioic acid-S-methyl ester, ASM), 2,6-dichloro-isonicotinic acid (DCINA), salicylic acid (SA), and dibasic potassium phosphate (K2HPO4) were tested for their ability to protect cashew (Anacardium occidentale) seeds and leaves from anthracnose disease caused by Colletotrichum gloeosporioides. No inhibition of the early stages of pathogen development was caused by concentrations equal to or lower than 1.1mM a.i. ASM, 1.2mM a.i. DCINA, 5mM SA and 50mM K2HPO4. Maximum reduction of the disease in detached leaves, without phytotoxic effects, was obtained with 0.07mM a.i. ASM and DCINA, 5mM SA, and 50mM K2HPO4, with a time interval of at least 72h between application of the activator and inoculation with the pathogen. On attached leaves, foliar sprays were slightly more efficient than soil drench treatments, with 5mM SA being the most effective treatment, while 50mM SA as well as 0.3mM a.i. ASM and DCINA caused phytotoxic effects. In field-grown plants, protection was conferred by a soil drench of concentrations as low as 12.6M a.i. ASM and DCINA and 2.6mM SA. These concentrations were not phytotoxic suggesting that plant defence activators have potential for control of anthracnose disease in the field.  相似文献   
12.
Algarrobo (Prosopis alba) is an important nitrogen-fixing tree adapted to the semiarid regions of northwestern Argentina. The tree provides fuelwood and dimensionally stable lumber for flooring and furniture; its pods that have a high sugar content are consumed by livestock and humans. P. alba has been one of the most heavily harvested species. This paper reports on the evaluation of a nine-year-old Prosopis alba progeny trial containing 57 half-sibling families of eight provenances in northwestern Argentina (of the 1,596 trees planted, 1,289 survived in 1999). Considering the multiple uses of P. alba, the selection criteria included: total biomass production (from basal diameter using regression equations), height, rate of pod production, and pod sensory characteristics. The family-narrow-sense-heritability was 0.487 for height. 0.548 for biomass production, and 0.244 for pod production. In 1998, 12 of the 1,289 trees were more than 4 m tall and had more than 1.75 kg pods per tree; and their pods had a sweet or very sweet non-astringent taste. Scions from these 12 trees were successfully grafted onto unselected P. alba rootstock. These are currently being used to produce rooted cuttings. The pod production, biomass, and height of the 12 clones ranged from 6.55 to 14.4, 1.57 to 13.5, and 1.29 to 1.70 times the respective population means. The genetic gains of 13.5%, 77%, and 147% for height, biomass, and pod production respectively are greater than genetic gains for other tree species and are probably due to the great genetic variability in the local population and the lack of any prior genetic improvement program.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   
13.
Clement  C.R.  Weber  J.C.  van Leeuwen  J.  Astorga Domian  C.  Cole  D.M.  Arévalo Lopez  L.A.  Argüello  H. 《Agroforestry Systems》2004,61(1-3):195-206
Agroforestry Systems - Peach palm (Bactris gasipaes) was domesticated as a fruit crop by the first Amazonians in traditional Neotropical agroforestry systems, but research and development...  相似文献   
14.
Fady  B.  Ducci  F.  Aleta  N.  Becquey  J.  Diaz Vazquez  R.  Fernandez Lopez  F.  Jay-Allemand  C.  Lefèvre  F.  Ninot  A.  Panetsos  K.  Paris  P.  Pisanelli  A.  Rumpf  H. 《New Forests》2003,25(3):211-225
Adaptive and wood quality trait data were collected and analyzed on commercially available Juglans regia and J. regia×J. nigra provenances and progenies planted across Europe in a multi-site network. A total of 19 seed sources, replicated 35 times per site, were planted at 13 sites from 5 European countries, encompassing the potential distribution area of timber production plantation sites. The following traits were evaluated: survival, height, diameter at breast height, stem form, apical dominance, vegetative budbreak, along with biotic and abiotic damage. Mean values were significantly different both among provenances/progenies and sites. Most common damage was late spring and early autumn frost. Bud break ranking was significantly correlated with provenance and progeny origin. Although J. regia is fast growing, southern European early budbreak plant material should not be planted under most middle European conditions where late spring frost can be expected, as it has a significant negative impact on architectural (and thus wood quality) traits. Hybrid J. regia×J. nigra progeny performed better than J. regia provenances/progenies for most traits measured. Differences were significantly in favor of hybrids at sites with medium to low fertility, although some locally selected seed sources tended to perform as well as hybrids on high fertility sites.  相似文献   
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16.
The conceptual structure of the field of Animal Science (AS) research is examined by means of a longitudinal science mapping analysis. The whole of the AS research field is analysed, revealing its conceptual evolution. To this end, an automatic approach to detecting and visualizing hidden themes or topics and their evolution across a consecutive span of years was applied to AS publications of the JCR category ‘Agriculture, Dairy & Animal Science’ during the period 19452011. This automatic approach was based on a coword analysis and combines performance analysis and science mapping. To observe the conceptual evolution of AS, six consecutive periods were defined: 19451969, 19701979, 19801989, 19901999, 20002005 and 20062011. Research in AS was identified as having focused on ten main thematic areas: ANIMAL‐FEEDING, SMALL‐RUMINANTS, ANIMAL‐REPRODUCTION, DAIRY‐PRODUCTION, MEAT‐QUALITY, SWINE‐PRODUCTION, GENETICS‐AND‐ANIMAL‐BREEDING, POULTRY, ANIMAL‐WELFARE and GROWTH‐FACTORS‐AND‐FATTY‐ACIDS. The results show how genomic studies gain in weight and integrate with other thematic areas. The whole of AS research has become oriented towards an overall framework in which animal welfare, sustainable management and human health play a major role. All this would affect the future structure and management of livestock farming.  相似文献   
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18.
An analytical method has been developed for the determination of total bound and extractable residues of the nitrofuran drugs furazolidone, nitrofurazone, furaltadone, and nitrofurantoin in milk of dairy cows. The method involves overnight acid hydrolysis and simultaneous derivatization of the released side chains with 2-nitrobenzaldehyde. During hydrolysis, the bound metabolites are hydrolyzed to the side chains. After pH adjustment and solid-phase extraction cleanup, the derivatives are detected and quantitated using a liquid chromatography-tandem mass spectrometry system with an atmospheric pressure chemical ionization interface. Validation of the method is accomplished by fortifying control milk with a mixture of side chains at 1, 2, and 4 ng/g. Internal standards are added at the beginning of the procedure to compensate for matrix effects and recovery losses. Method accuracies range from 83 to 104% with coefficients of variation less than 13% for all four analytes. The limits of detection are相似文献   
19.
Two commercial shrimp farms in south Texas were evaluated for influent and effluent water quality from June to October 1994. The intensive farm, Taiwan Shrimp Village Association (TSV) had an average annual yield of 4630 kg ha?1 while the semi‐intensive farm, Harlingen Shrimp Farm (HSF), had a yield of 1777 kg ha?1. The study had three objectives: (1) to compare influent and effluent water from the intensive and semi‐intensive shrimp farms, (2) to show which effluent water‐quality indicators exceeded allowable limits, (3) to indicate inherent problems in farms operated with water exchange and summarize how findings from this study led to changes in farms' management that limited potential negative impact on receiving streams. Water samples were collected and analysed twice a week for the TSV farm and once a week for the HSF farm. Samples were analysed for dissolved oxygen (DO), salinity, pH, ammonia‐nitrogen (NH3‐N), nitrite‐nitrogen (NO2‐N), nitrate‐nitrogen (NO3‐N), total phosphorus (TP), total reactive phosphorus (TRP), five‐day carbonaceous biochemical oxygen demand (cBOD5), total suspended solids (TSS) and settleable solids (SettSols). Most of the effluent constituents showed fluctuations throughout the sampling period often related to harvest activity. Effluent pH at TSV was lower than influent values but within the regulatory requirements set by Texas Commission of Environmental Quality (TCEQ), formerly known as Texas Natural Resource Conservation Commission (TNRCC). HSF effluent pH values were higher than its influent, but still within TCEQ limits. Effluent DO mean levels were generally below the regulatory daily mean requirement, with values at TSV often below those for influent. Effluent nutrient concentrations and net loads were generally higher at the intensive shrimp farm, with NH3‐N mean concentrations above the daily mean set by the TCEQ on several occasions. Effluent TSS concentrations were higher than influent for both farms, with daily mean values above the TCEQ limit. The two farms presented similar TSS concentrations despite their different stocking densities. However, TSS total net load and net load per hectare were higher at the intensive farm. The semi‐intensive farm presented higher cBOD5 concentrations and net loads despite its lower stocking density, with daily mean values above the TCEQ limit. The cBOD5 net load at TSV presented negative values indicating higher load at the influent than at the effluent. Analyses showed no evidence of self‐pollution between influent and effluent at the two farms. The high feed conversion ratio (FCR) values (2.3 and 2.7 for the intensive and the semi‐intensive farm respectively) suggest that better feed management is needed to reduce nutrient and solid net loads release from the two farms. The data obtained from this study resulted in several modifications in design and management of the two farms that reduced the potential negative impact on receiving streams. A brief summary of the improvement in selected effluent water‐quality indicators at the intensive shrimp farm is provided.  相似文献   
20.
A 2-year-old heifer was presented with masses on her anus that were interfering with cervical manipulation during embryo flushing. The masses had broad stalks attached within the anal sphinchter. Recovery was without incident after surgical resection. No recurrence of the masses had occurred 3 months later. Histologic diagnosis was benign leiomyoma.  相似文献   
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