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排序方式: 共有2135条查询结果,搜索用时 15 毫秒
971.
Abdul Omar Nur-Shakirah Mohd Safie Khadijah Yee Jia Kee Abd Rahim Huda-Shakirah Abu Bakar Mohd Hafifi Yakath Ali Nurul-Aliyaa Bee Lynn Chew Latiffah Zakaria Nik Mohd Izham Mohamed Nor Subramaniam Sreeramanan Yin-Hui Leong Masratul Hawa Mohd 《Plant pathology》2022,71(7):1594-1605
Fig (Ficus carica) is an exotic deciduous plant that is grown worldwide. Fungal diseases pose a major threat to fig plants, affecting their fruit quality and production. This study was conducted to characterize the fungal isolates associated with leaf blight, stem rot and fruit rot of F. carica in Malaysia through morphological analysis, DNA sequencing, multigene phylogenetic analysis and pathogenicity tests. From September 2018 to March 2019, 30 blighted leaves and 30 rotted stems and fruits of F. carica were collected from several nurseries in Malaysia. Thirty fungal isolates that belonged to Lasiodiplodia theobromae (27 isolates) and L. brasiliensis (three isolates) were identified based on morphological characteristics, comparison of DNA sequences and phylogenetic analysis of the internal transcribed spacer (ITS), elongation translation factor 1-α (tef1-α), β-tubulin (tub2) and DNA-directed RNA polymerase II subunit (rpb2). Among the 27 isolates of L. theobromae, nine isolates were obtained from leaves, eight isolates from stems and 10 isolates from fruits, whereas the three isolates of L. brasiliensis were obtained from stems (two isolates) and a leaf (one isolate). The results of pathogenicity tests revealed that L. theobromae and L. brasiliensis isolates were responsible for leaf blight and stem rot of F. carica, whereas fruit rot was caused by L. theobromae isolates. The present study highlighted two different species, L. theobromae and L. brasiliensis, as the causal agents of leaf blight and stem rot of F. carica. Additionally, L. theobromae caused fruit rot of F. carica in Malaysia. 相似文献
972.
建立了土壤中芸薹根肿菌荧光定量PCR(qPCR)快速检测及风险预警体系。确定了芸薹根肿菌qPCR检测的特异性引物PbF/PbR,对根肿菌质粒DNA的检测灵敏度为1.612×10-6 ng·μL-1,比普通PCR高出1 000倍;对土壤和基质中芸薹根肿菌孢子的最低检测下限均为10 个·g-1,而土壤和基质带菌的发病阈值分别为100和1 000 个·g-1,高于该浓度时根肿病发生风险大。本研究建立的芸薹根肿菌qPCR技术体系检测下限远低于发病阈值,可以快速、准确、定量地检测出采自四川绵阳、湖北恩施、江苏无锡、山东青岛、辽宁沈阳、山西运城、内蒙古巴彦淖尔和宁夏固原等8个地区的27份田间土壤中芸薹根肿菌的数量,实现对十字花科根肿病的监测预警,为制定产前病害防控方案提供依据。 相似文献
973.
为有效防控十字花科蔬菜生产中的毁灭性病害——根肿病,以尖孢镰孢菌Fusarium oxysporum和辣椒疫霉Phytophthora capsici为指示菌,利用平板对峙法对分离自土壤的1 198株细菌进行筛选,进通过盆栽试验筛选对十字花科根肿病具有良好防效的生防菌株,并基于形态学特征、生理生化特性及16S rDNA、gyrB和atpD多基因系统发育分析对生防菌株进行鉴定,同时测定其抑菌谱和田间防效。结果表明,通过对峙培养筛选获得115株有抑菌效果的生防菌株,采用盆栽试验获得1株对根肿病菌具有拮抗效果的菌株,命名为ZF480。结合形态学特征和系统发育分析结果将该菌株鉴定为副地衣芽胞杆菌Bacillus paralicheniformis。菌株ZF480对野油菜黄单胞野油菜变种Xanthomonas campestris pv. campestris等10种病原菌具有拮抗效果,抑菌谱较宽,对白菜根肿病的盆栽防效和田间防效分别达到72.82%和64.08%。表明副地衣芽胞杆菌菌株ZF480对十字花科根肿病具有显著的防效,可作为生防菌进一步开发利用。 相似文献
974.
Mohseni MA Soleimanpour J Mohammadpour H Shahsavari A 《Pakistan journal of biological sciences: PJBS》2011,14(8):490-495
Although the intramedullary nailing is thought to be the method of choice for treatment of closed tibial shaft, there is ongoing debate on the optimal surgical approach in patients with open types of these fractures. In addition, choosing between the reamed and unreamed intramedullary nailing is still an issue for the orthopedic surgeons. In present study, we aimed to compare the outcome and consequences of OA tubular external fixation vs. unreamed intramedullary nailing in open grade IIIA-IIIB tibial shaft fractures. In a randomized clinical trial, 50 patients with open tibial shaft fractures (grades IIIA-IIIB) were recruited in Tabriz Shohada teaching centre in a 2-year period of time. They randomized in two equal groups underwent either AO tubular external fixation or unreamed intramedullary nailing. These 2 groups were matched for sex, age and fracture-grade. The follow-up time was one year. Union time, surgical outcome, postoperative complications and the ambulation time were compared between the two groups. Twenty five patients, 20 males and 5 females with a mean age of 30.80 +/- 5.24 years were allocated in unreamed intramedullary group and 25 other patients, 22 males and 3 females with a mean age of 28.92 +/- 8.88 years were studied in the external fixation group (p = 0.70 and 0.37, respectively). The two groups were matched for sex (p = 0.70) and age (p = 0.37). The time of union was 3, 4, 5 and 6 < or = weeks after operation in 28, 12, 32 and 28% of the cases in unreamed intramedullary group vs. 4, 12, 48 and 36% of the cases in external fixation group, respectively (p = 0.14). Post-operative infection, soft tissue injury, malunion and nonunion were documented in 16, 8, 0 and 4% of the cases in unreamed intramedullary group vs. 32, 12, 24 and 8% of the cases in external fixation group, respectively (p = 0.19, 0.50, 0.02 and 0.50, respectively). The mean ambulation time after operation was 2.92 +/- 2.43 weeks in the unreamed intramedullary nailing group vs. 2.68 +/- 2.14 weeks in the external fixation group (p = 0.71). Our results are in favor of unreamed intramedullary nailing against external fixation in treatment of open tibial shaft fractures. 相似文献
975.
Said AW Usui T Shinya K Ono E Ito T Hikasa Y Matsuu A Takeuchi T Sugiyama A Nishii N Yamaguchi T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(4):541-544
A sero-epidemiological survey of human and equine H3 influenza A virus infections in dogs and cats using the hemagglutination inhibition (HI) and neuraminidase inhibition (NI) tests was conducted. Serum samples were collected from 582 dogs and 237 cats in Japan during the periods 2002-2008 and 1997-2008, respectively. Although no HI antibodies against equine H3 virus were detected, 9 (3.8%) from cats and 12 (2.1%) from dogs were HI-positive against human H3 virus. Only one serum each from dogs and cats was NI-positive against N2 virus. These findings suggest that although equine H3 influenza virus infections have not been prevalent in companion animals, human H3N2 influenza A virus infections have occurred in dogs and cats in recent years in Japan. 相似文献
976.
Construction of DNA vaccines encoding Eimeria acervulina cSZ-2 with chicken IL-2 and IFN-γ and their efficacy against poultry coccidiosis 总被引:1,自引:0,他引:1
Muhammad Ali A. Shah 《Research in veterinary science》2011,90(1):72-77
The study describes vaccination experiments with highly immunogenic sporozoite E. acervulina cSZ-2 co-administered with chicken IL-2 (chIL-2) and interferon-γ (chIFN-γ) to determine their efficacies against homologue challenge. The entire coding sequence of cSZ2, chIL-2 and chIFN-γ were cloned into eukaryotic expression vector pVAX1, constructing DNA vaccines pVAX1-cSZ2, pVAX1-chIL-2, pVAX1-chIFN-γ, pVAX1-cSZ2-chIL-2 and pVAX1-cSZ2-chIFN-γ. The expression of target genes in vivo was detected by RT-PCR and Western blot. Chicken experiments were carried out by vaccinating chickens two times at dose rate of 100 μg intramuscularly. At 28 days of age, all chickens were inoculated orally with 1 × 105 sporulated oocysts of E. acervulina except the unchallenged control group. Seven days after challenge, all chickens were weighted and slaughtered for duodenum collection. The results indicated that these DNA vaccines were successfully constructed and the antigen genes could be expressed effectively in vivo. The findings also demonstrated best synergistic effect of IL-2 with this protein which suggested that co-administration of cytokines with this antigen was a powerful method to enhance immunity by alleviating intestinal lesions, body weight loss and oocyst count imparting partial protection against homologous challenge. 相似文献
977.
Purpose
The purpose of this study was to evaluate the brain, renal, and hepatic effects of three NSAIDs (flunixin meglumine, ketoprofen, and phenylbutazone) when administered IV to clinically normal Iranian fat-tailed sheep. 相似文献978.
Ghafouri-Kesbi F Abbasi MA Afraz F Babaei M Baneh H Abdollahi Arpanahi R 《Tropical animal health and production》2011,43(6):1153-1159
Genetic parameters for average daily gain from birth to weaning (ADGa), birth to 6 months (ADGb), weaning to 6 months (ADGc),
weaning to yearling age (ADGd), and corresponding Kleiber ratios (KRa, KRb, KRc, and KRd) were estimated by using records
of 3,533 Zandi lambs, descendent of 163 sires and 1265 dams, born between 1991 and 2005 at the Zandi Sheep Breeding Station
at Khojir National Park, Tehran, Iran. A derivative-free algorithm combined with a series of six single-trait linear animal
models was used to estimate phenotypic variance and its direct, maternal, and residual components. In addition, bivariate
analyses were done to estimate (co)variance components between traits. Estimates of direct heritability (h
2
) were 0.11, 0.15, 0.09, 0.10, 0.10, 0.10, 0.06, and 0.07 for ADGa, ADGb, ADGc, ADGd, KRa, KRb, KRc, and KRd, respectively,
thereby indicating the presence of low additive genetic variation for growth rate and Kleiber ratio in this population of
Zandi sheep. Maternal genetic component was found to be significant on ADGa and KRa and contributed 3% and 5%, respectively,
in total phenotypic variance of ADGa and KRa. A widespread range of genetic correlations among traits studied was observed.
Except for negative genetic correlations between ADGa and KRc, ADGa and KRd, and between KRa and KRc, in other cases, genetic
correlations were positive and moderate to very high. Phenotypic correlations ranged from −0.49 (ADGa/KRd) to 0.94 (ADGc/KRc).
These results indicate that selecting for improved growth rate or Kleiber ratio in Zandi sheep would generate a relatively
slow genetic progress. 相似文献
979.
Mohammad Reza Dadpour Somayeh Naghiloo Seyed Hadi Peighambardoust Sima Panahirad Maryam Aliakbari Ali Movafeghi 《Scientia Horticulturae》2011
A comparative study of floral ontogeny in normal and double-flowered phenotype of Syringa vulgaris was conducted using the epi-illumination light microscopy. In the wild phenotype, floral differentiation starts with calyx inception and the formation of four sepals in orthogonal positions (two median and two lateral). The corolla emerges as a continuous ring-like structure leading to the appearance of four petal lobes alternating with the sepals. Androecium was formed by initiation of two stamen primordia in transverse plane and finally the bicarpellate gynoecium emerges in median position. In the case of the double-flowered lilac, there are supernumerary petals in an additional whorl. In double-flowered phenotype, a ring meristem is formed acropetally after the first petal whorl initiates. Stamens and carpels initiated similarly in double-flowered as well as in wild-type plants. However, position of stamens deviates from the typical transverse situation. It seems that the appearing of an extra petal whorl did not exhibit any adverse effect on the initiation of other whorls, in terms of organ identity. Therefore, it would be suggested that the double-flowered phenotype of Syringa represents a case of neoheterotopy, with formation of an extra petal whorl, rather than a case of homoheterotopy with transformation of an ancestral androecium whorl into petals. 相似文献
980.
Emna Ayari-Fakhfakh Abdeljelil Ghram Ali Bouattour Imen Larbi Latifa Griba-Dridi Olivier Kwiatek Michle Bouloy Genevive Libeau Emmanuel Albina Catherine Cêtre-Sossah 《Veterinary journal (London, England : 1997)》2011,187(3):402-404
This study, carried out between September 2006 and January 2007, is the first cross-sectional serological investigation of peste-des-petits-ruminants (PPR) and Rift Valley fever (RVF) in Tunisia. The objective was to assess the potential need to develop a dual, recombinant PPR–RVF vaccine and how such a vaccine might be utilised in Tunisia. An overall PPR seroprevalence of 7.45% was determined, a finding supported by the high specificity (99.4%) and sensitivity (94.5%) of the ELISA used. On assessment of the diversity and density of mosquitoes in the sampling area, four species of RVF-vectors of the genus Aedes and Culex were identified. However, no serological evidence of RVF was found despite the use of a highly sensitive ELISA (99–100%). Larger scale investigations are underway to confirm these findings and the continuation of the emergency vaccination program against these two diseases remains valid. 相似文献