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61.
The carambola (Averrhoa carambola L., family Oxalidaceae) is believed to have originated in Sri Lanka and the Moluccas but it has been cultivated in southeast Asia and Malaysia for many centuries. The evergreen tree is slow-growing, has a rounded crown and reaches 6 to 9 m in height. The 5- to 6-angled fruits (6 to 15 cm long and up to 9 cm wide) have thin, waxy, orange-yellow skin and juicy, yellow flesh. The fruit has a more or less pronounced oxalic acid odor and the flavor ranges from very sour to middle sweetish. The carambola is a tropical and subtropical tree, it can tolerate freezing temperature (?2°C) for short periods and sustain little damage. Trees can be propagated by seed, grafting, budding, and air layering. Tissue culture propagation has met only limited success. Plant spacing varies with growing region and cultural practices. Tree training is practiced intensively in different countries. Harvest timing and postharvest handling are critical to successful marketing of fresh fruit. Carambola is a nonclimateric fruit. Growers carefully harvest fruit by hand at color break — light green fruit with yellow color. The storage conditions should be 5 to 10°C and 85 to 95% relative humidity. Most carambola fruit is eaten fresh, used in salads, desserts, and cooked as star-shaped slices; fruit can also be dried, canned and frozen. The leaves have been eaten as a substitute for sorrel. Commercial production occurs in Taiwan, Malaysia, southern China, the Philippines, Australia, USA (Florida, Hawaii), Brazil, Suriname and Guyana. Production and consumption appears on the rise throughout the world and will most likely increase as selection and breeding for superior tasting cultivars with improved handling characteristics and storage conditions are found.  相似文献   
62.
Zusammenfassung In den Jahren 1999 bis 2003 wurde in Freiland-, Klimakammer- und Lagerungsversuchen überprüft, ob ein Risiko für die Übertragung des Erregers der Bakteriellen Ringfäule der Kartoffel (Clavibacter michiganensis ssp. sepedonicus) besteht, wenn (a) gesunde Kartoffelknollen in Kontakt mit Maschinen und Geräten kommen, die mit dem Erreger kontaminiert sind (indirekter Kontakt) und (b) gesunde Kartoffelknollen direkt in Kontakt mit infizierten Knollen kommen (direkter Kontakt). Nach indirektem Kontakt konnte nur beim nachfolgenden Anbau der kontaminierten Knollen in der Klimakammer Befall in Kraut und Knollen festgestellt werden. Im Freiland konnte der Erreger, auch bei wiederholtem Nachbau der geernteten Knollen, nicht nachgewiesen werden. Nach direktem Kontakt und nachfolgendem Anbau der kontaminierten Knollen in der Klimakammer und im Freiland, wurde der Erreger in allen Fällen in den geerntete Knollen nachgewiesen. Befall im Kraut wurde nur in dem Klimakammerversuch und in einem Freilandversuch ermittelt. Wurden durch direkten Kontakt kontaminierte Knollen eingelagert, konnte der Erreger in allen untersuchten Knollen festgestellt werden. Insgesamt besteht ein hohes Risiko, dass gesunde Knollen infiziert werden, wenn oberflächliche Kontaminationen mit dem Erreger erfolgen. Die Wahrscheinlichkeit von Infektionen steigt mit zunehmender Kontaminationsstärke.  相似文献   
63.
Xiphinema diversicaudatum and X. index are vector nematode species of economic importance in viticulture regions as they can transmit Arabis Mosaic, Grapevine Fanleaf and Strawberry Latent Ringspot viruses to grapevine. Wang et al. (2003) designed species-specific diagnostic primers from ribosomal genes for both these vector species as well as a vector and a non-vector species X. italiae and X. vuittenezi, respectively. Our study aimed to confirm the specificity and determine the sensitivity and reliability of the primers for the two vector species, X. diversicaudatumand X. indexwhen challenged with closely related longidorid species and general nematode communities typical of vineyard soil. With one exception, no PCR product was observed when the primers were tested against six Longidorus, one Paralongidorus and one Xiphinema non-target species. Occasionally (three out of eight replicate PCR reactions) a weak PCR product was noted when primers for X. index were tested with L. elongatus. Furthermore, when challenged with a range of non-target nematode species comprising the nematode community typical of viticulture soil, no PCR product was amplified. An experimental dilution series of extracted DNA rigorously demonstrated that DNA from an equivalent single specimen of the target virus-vector species, X. diversicaudatum and/or X. index, could be detected amongst 1000 equivalent non-targetX. vuittenezi. Also, extracted DNA from an equivalent single target specimen was detected when added to DNA extracted from the overall soil nematode community. The primers were assessed further by using serial mixtures of actual nematodes rather than extracted DNA to simulate field soil. Using this method, a single target nematode could be detected amongst 200 non-target specimens. Given their specificity, sensitivity and reliability, it appears that these diagnostic primers will be of great benefit to phytosanitary/quarantine services related to the viticulture industry.  相似文献   
64.
The swine pathogen Actinobacillus pleuropneumoniae serotype 1 was investigated for its ability to adhere to swine, rat, and human buccal epithelial cells (BEC). The highest number of bacteria adhered was to swine BEC. This binding ability was affected by heating, extreme pH, treatment with sodium dodecyl sulfate, ethylenediamine tetraacetate, or periodate, and proteolysis, suggesting that cell-surface glycoproteins participate in adherence and that adherence is based mostly on ionic interactions. Mannose and swine fibronectin may play a direct role in this interaction. Convalescent-phase serum from naturally infected pigs inhibited the adhesion. There was a correlation between bacterial pathogenicity as well as host specificity and the capacity for adherence to swine BEC. Adhesion to swine BEC provides a convenient method to study in vitro the adherence of A. pleuropneumoniae and other pathogens of the pig respiratory tract.  相似文献   
65.
Microcosm studies were carried out to test the survival of Ralstonia solanacearum biovar 2 (race 3) in soil at the permanent wilting point (wp) water content and at field capacity (fc) water content and on various material. Soils were placed at permanent ?5°C, 4°C, 15°C and 20°C and weekly fluctuating ?10/0/+10°C and the material at 5, 15 °C, 20°C with relative humidity (rh) uncontrolled or at constant 10% or 90%. In soil, survival was clearly dependent on temperature independent of water content. At 20°C Ralstonia solanacearum could be reisolated up to 364 days, at 15°C up to 290 days, at 4°C up to 209 days and at fluctuating temperatures (?10/0/+10°C) only up to 18 days. The lower the temperature, the more the population declined. At 15°C and 20°C appr. 107 cfu/g soil were detected after 100 days, whereas at ?5°C only 102 cfu/g soil were detected after only 18 days. The pathogen was longer detectable in sandy-clay loam than in lighter sandy soil. It could be longer reisolated at wilting point and the populations did not decline as rapidly as at field capacity. Ralstonia solanacearum could best survive on material surfaces like rubber, plastic and varnished metal with maximum survival of 40 days at 5°C and 10% rh. In general there is a low risk of Ralstonia solanacearum overwintering under European climatic conditions when the fields are cleared of plant debris and the soil is frozen. Contamined material surfaces pose the risk of pathogen transmission to healthy tubers.  相似文献   
66.
Irisin, a novel peptide, was initially been shown to be expressed explicitly in the muscle tissues. We studied the presence of irisin immunoreactivity in porcupine adrenal glands and kidneys. Immunocytochemistry showed that irisin was localised both in the adrenal cortex and adrenal medulla. In organs, irisin immunoreactivity was found in the tubular and collecting system of the nephron. The functional role of irisin in the adrenal gland and kidney has not been precisely yet. However, irisin might have a paracrine and autocrine function as do other locally produced peptides.  相似文献   
67.
Tropical Animal Health and Production - A study was conducted to determine the effects of varied brooding regimes on the performance of small bronze turkey poults and their grow-outs. One hundred...  相似文献   
68.
69.
The aim of this project is to study the clinical signs and lesion of velogenic Newcastle disease (vND) in commercial turkeys, and also to find out if La Sota vaccination offered protection against these signs and lesions. The cockerels were included as positive controls. One hundred and twenty turkey poults and cockerels were divided into eight groups as follows: unvaccinated unchallenged turkeys (UUT), unvaccinated challenged turkeys (UCT), vaccinated unchallenged turkeys (VUT), vaccinated challenged turkeys (VCT), and along the same lines, the cockerel groups were UUC, UCC, VUC and vaccinated challenged cockerels (VCC). Vaccination was at 3 weeks of age while challenge was at 6 weeks of age. The unvaccinated turkeys and cockerels (UCT and UCC) showed different degrees of depression, diarrhoea and later paralysis at challenge. Total mortality was 100% in cockerels within 6 days, but 60% in turkeys. Similar but milder clinical signs were found in the VCC with a total mortality of 13.3%. The VCT showed mild drop in feed and water consumption, and no mortality. All the challenged groups had significant (p < 0.05) loss of weight when compared with their controls. Necropsy showed that while the UCC had severe proventricular haemorrhages, intestinal and caecal tonsil ulcers, the UCT had no digestive tract lesion. There was severe atrophy of the lymphoid organs in all the challenged groups. Histopathological sections of the bursa, spleen and thymus in all the challenged groups with special emphasis on the vaccinated and unvaccinated turkeys with mortalities of 0 and 60%, respectively, had very severe necrosis and depletion of the lymphoid tissue. Virus was isolated from the cloacal swabs. The haemagglutination inhibition antibodies were significantly higher (p < 0.05) in the challenged groups than the unchallenged. The above observations in the intestinal tracts of UCT are of diagnostic significance while the gross and microscopic lesions in the UCT and VCT show that La Sota vaccination may not protect turkeys against the destruction of the lymphoid organs by vND as earlier reported in chickens. This may lead to immunosuppression and production problems in areas where vND is enzootic.  相似文献   
70.
Foal first diarrhoea is one of the most prominent problems in the early life of horses. Probiotics might have the potency to prevent or at least diminish neonatal diarrhoea. We hypothesised that the treatment of foals with probiotic strains of Lactobacillus rhamnosus and Enterococcus faecium starting early after birth and then daily over 2 weeks would prevent or mitigate foal heat diarrhoea. The influence of this probiotic treatment on diarrhoea incidence and growth and health performance of young foals was investigated. Thirty‐four foals were randomly allocated to two groups. From day 1 to 14 of life, the foals received either placebo (PG, n = 16) or the probiotic treatment (TG, n = 18). Clinical examination was performed, and the faeces consistency score (FCS, 1–5; with diarrhoea defined by ≤3) was recorded once per day in weeks 1 and 2 and once weekly in weeks 3–8 of life (WL). The body height was measured at birth and after two and eight WL. Diarrhoea occurred in the 1st WL in 19% and 61% of PG and TG foals respectively. In the 1st WL, diarrhoea lasted 0.3 ± 0.8 and 1.6 ± 1.4 days in PG and TG foals respectively. In the 2nd WL, diarrhoea occurred in 94% and 84% of PG and TG foals, respectively, and lasted for 3.0 ± 1.5 and 3.7 ± 1.6 days respectively. At least two periods of diarrhoea developed in 33% and 65% of PG and TG foals respectively. The TG foals grew slightly slower than the PG foals. The results indicated that the probiotic treatment of neonatal foals as performed in this study was not suitable to reduce diarrhoea within the first two WL, because contrary to the hypothesis, the TG foals suffered more frequently and for longer periods from diarrhoea than the PG foals.  相似文献   
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