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71.
Wilt and root rot disease in plants has been caused mainly by Fusarium species. Previous studies reported that members of the Fusarium oxysporum species complex (FOSC) were usually associated with this disease, but there has been no report of it being caused in rice by specific Fusarium species. However, in this study, Fusarium commune was identified and characterized as a causal agent of wilt and root rot disease of rice. Four Fusarium isolates (BD005R, BD014R, BD019R, and BD020R) were obtained from different parts (root, stem, and seeds) of diseased rice plants. In morphological studies, these isolates produced key characteristics of F. commune, such as long and slender monophialides, polyphialides, and abundant chlamydospores. In molecular studies, the isolates were identified as F. commune based on sequences of the translation elongation factor 1-α (TEF1) gene that had 99.7%–100% sequence identity with the reference strain F. commune NRRL 28058. The phylogenetic tree showed that all four isolates belonged to the F. commune clade. A mating type test determined that three isolates carried MAT1-2. Their teleomorph stage was still unknown. Pathogenicity assays showed that all the isolates produced wilt and root rot symptoms and the isolate BD019R was observed as the most virulent among the isolates. To our knowledge, this is the first report of F. commune causing wilt and root rot disease on rice. 相似文献
72.
AM Luciano F Franciosi V Lodde F Perazzoli M Slezáková S Modina 《Reproduction in domestic animals》2009,44(3):480-488
Joining immature gamete cryopreservation and germinal vesicle transplantation (GVT) technique could greatly improve assisted reproductive technologies in animal breeding and human medicine. The present work was aimed to assess the most suitable cryopreservation protocol between slow freezing and vitrification for immature denuded bovine oocytes, able to preserve both nuclear and cytoplasmic competence after thawing. In addition, the outcome of germinal vesicle transfer procedure and gamete reconstruction was tested on the most effective cryopreservation system. Oocytes, isolated from slaughterhouse ovaries, were stored after cumulus cells removal either by slow freezing or by vitrification in open pulled straws. After thawing, oocytes were matured for 24 h in co-culture with an equal number of just isolated intact cumulus enclosed oocytes, and fixed in order to evaluate the stage of meiotic progression and cytoskeleton organization. Our results showed that after warming, vitrified oocytes reached metaphase II (MII) in a percentage significantly higher than oocytes cryopreserved by slow freezing (76.2% and 36.5% respectively, p < 0.05). Moreover, vitrification process preserved the organization of cytoskeleton elements in a higher proportion of oocytes than slow freezing procedure. Therefore vitrification has been identified as the elective method for denuded immature oocytes banking and it has been applied in the second part of the study. Our results showed that 38.3% of oocytes reconstructed from vitrified gametes reached the MII of meiotic division, with efficiency not different from oocytes reconstructed with fresh gametes. We conclude that vitrification represents a suitable method of GV stage denuded oocyte banking since both nuclear and cytoplasmic components derived from cryopreserved immature oocytes can be utilized for GVT. 相似文献
73.
RA McKenzie AM Carmichael ML Schibrowski SA Duigan JA Gibson JD Taylor 《Australian veterinary journal》2009,87(1-2):27-32
Polioencephalomalacia was diagnosed histologically in cattle from two herds on the Darling Downs, Queensland, during July–August 2007. In the first incident, 8 of 20 18-month-old Aberdeen Angus steers died while grazing pastures comprising 60% Sisymbrium irio (London rocket) and 40% Capsella bursapastoris (shepherd's purse). In the second incident, 2 of 150 mixed-breed adult cattle died, and another was successfully treated with thiamine, while grazing a pasture comprising almost 100% Raphanus raphanistrum (wild radish). Affected cattle were either found dead or comatose or were seen apparently blind and head-pressing in some cases. For both incidents, plant and water assays were used to calculate the total dietary sulfur content in dry matter as 0.62% and 1.01% respectively, both exceeding the recommended 0.5% for cattle eating more than 40% forage. Blood and tissue assays for lead were negative in both cases. No access to thiaminase, concentrated sodium ion or extrinsic hydrogen sulfide sources were identified in either incident. Below-median late summer and autumn rainfall followed by above-median unseasonal winter rainfall promoted weed growth at the expense of wholesome pasture species before these incidents. 相似文献
74.
AM See KL Swindells MJ Sharman KL Haack D Goodman A Delaporta I Robertson SF Foster 《Australian veterinary journal》2009,87(7):292-295
Objective To establish reference values for activated coagulation time (ACT) in normal cats and dogs, by visual assessment of clot formation using the MAX-ACTTM tube.
Subjects We recruited 43 cats and 50 dogs for the study; 11 cats and 4 dogs were excluded from the statistical analysis because of abnormalities on clinical examination or laboratory testing including anaemia, prolonged prothrombin time (PT) or activated partial thromboplastin time (APTT), or insufficient plasma volume for comprehensive laboratory coagulation testing.
Procedure Blood samples were collected via direct venipuncture for MAX-ACT, packed cell volume/total solids, manual platelet estimation and PT/APTT measurement. Blood (0.5 mL) was mixed gently in the MAX-ACT tube at 37°C for 30 s, then assessed for clot formation every 5 to 10 s by tipping the tube gently on its side and monitoring for magnet movement. The endpoint was defined as the magnet lodging in the clot. The technique was tested with 10 dogs by collecting two blood samples from the same needle insertion and running a MAX-ACT on each simultaneously.
Results In normal cats the mean MAX-ACT was 66 s (range 55–85 s). In normal dogs the mean was 71 s (range 55–80 s). There was no statistical difference between the first and second samples collected from the same needle insertion.
Conclusions and Clinical Relevance In both cats and dogs, a MAX-ACT result >85 s should be considered abnormal and further coagulation testing should be performed. Additionally, failure to discard the first few drops of the sample does not appear to significantly affect results. 相似文献
Subjects We recruited 43 cats and 50 dogs for the study; 11 cats and 4 dogs were excluded from the statistical analysis because of abnormalities on clinical examination or laboratory testing including anaemia, prolonged prothrombin time (PT) or activated partial thromboplastin time (APTT), or insufficient plasma volume for comprehensive laboratory coagulation testing.
Procedure Blood samples were collected via direct venipuncture for MAX-ACT, packed cell volume/total solids, manual platelet estimation and PT/APTT measurement. Blood (0.5 mL) was mixed gently in the MAX-ACT tube at 37°C for 30 s, then assessed for clot formation every 5 to 10 s by tipping the tube gently on its side and monitoring for magnet movement. The endpoint was defined as the magnet lodging in the clot. The technique was tested with 10 dogs by collecting two blood samples from the same needle insertion and running a MAX-ACT on each simultaneously.
Results In normal cats the mean MAX-ACT was 66 s (range 55–85 s). In normal dogs the mean was 71 s (range 55–80 s). There was no statistical difference between the first and second samples collected from the same needle insertion.
Conclusions and Clinical Relevance In both cats and dogs, a MAX-ACT result >85 s should be considered abnormal and further coagulation testing should be performed. Additionally, failure to discard the first few drops of the sample does not appear to significantly affect results. 相似文献
75.
How introduced reptiles cause the loss of endemic reptiles is poorly understood and currently there are no available techniques for dealing with this major conservation issue. We addressed both these problems by investigating the role of the introduced house gecko Hemidactylus frenatus in causing the catastrophic decline and extinction of the endemic night gecko Nactus populations of the Mascarene Islands and how this introduced species can be excluded from habitats on the basis of morphology. Competition for enemy free space was tested in experimental enclosures and showed that H. frenatus displace the endemic Nactus coindemirensis and Nactus durrelli from favoured positions close to and from refugia, thus increasing the risk of predation and exposure to stochastic events. The ability of H. frenatus to grip substrates with their pad-bearing toes was examined, and we demonstrated that naturally occurring substrates with a greater amount of loose surface material of a higher particulate concentration and size excludes H. frenatus, but not Nactus. These findings support the hypothesis that H. frenatus led to the fragmentation and extinction of the endemic Nactus populations and demonstrate that artificial refugia made of a crumbly substrate may be used to limit future disturbances by this gecko and others like it in the Mascarene Islands and elsewhere. 相似文献
76.
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
77.
用欧拉羊杂交改良山谷型藏羊,对杂交F1代羔羊补饲兼放牧育肥试验,补饲阶段试验结果表明:经过90 d补饲,试验组增重10.88kg,比对照组高4.32 kg(P〈0.01),平均日增重0.121 kg,比对照组高0.048 kg;放牧育肥阶段试验结果表明:经过3个月放牧育肥,试验组增重9.09 kg,比对照组高2.67 kg(P〈0.05),平均日增重0.101 kg,比对照组高0.03 kg。 相似文献
78.
Dehal P Satou Y Campbell RK Chapman J Degnan B De Tomaso A Davidson B Di Gregorio A Gelpke M Goodstein DM Harafuji N Hastings KE Ho I Hotta K Huang W Kawashima T Lemaire P Martinez D Meinertzhagen IA Necula S Nonaka M Putnam N Rash S Saiga H Satake M Terry A Yamada L Wang HG Awazu S Azumi K Boore J Branno M Chin-Bow S DeSantis R Doyle S Francino P Keys DN Haga S Hayashi H Hino K Imai KS Inaba K Kano S Kobayashi K Kobayashi M Lee BI Makabe KW Manohar C Matassi G Medina M Mochizuki Y Mount S 《Science (New York, N.Y.)》2002,298(5601):2157-2167
The first chordates appear in the fossil record at the time of the Cambrian explosion, nearly 550 million years ago. The modern ascidian tadpole represents a plausible approximation to these ancestral chordates. To illuminate the origins of chordate and vertebrates, we generated a draft of the protein-coding portion of the genome of the most studied ascidian, Ciona intestinalis. The Ciona genome contains approximately 16,000 protein-coding genes, similar to the number in other invertebrates, but only half that found in vertebrates. Vertebrate gene families are typically found in simplified form in Ciona, suggesting that ascidians contain the basic ancestral complement of genes involved in cell signaling and development. The ascidian genome has also acquired a number of lineage-specific innovations, including a group of genes engaged in cellulose metabolism that are related to those in bacteria and fungi. 相似文献
79.
Aparicio S Chapman J Stupka E Putnam N Chia JM Dehal P Christoffels A Rash S Hoon S Smit A Gelpke MD Roach J Oh T Ho IY Wong M Detter C Verhoef F Predki P Tay A Lucas S Richardson P Smith SF Clark MS Edwards YJ Doggett N Zharkikh A Tavtigian SV Pruss D Barnstead M Evans C Baden H Powell J Glusman G Rowen L Hood L Tan YH Elgar G Hawkins T Venkatesh B Rokhsar D Brenner S 《Science (New York, N.Y.)》2002,297(5585):1301-1310
The compact genome of Fugu rubripes has been sequenced to over 95% coverage, and more than 80% of the assembly is in multigene-sized scaffolds. In this 365-megabase vertebrate genome, repetitive DNA accounts for less than one-sixth of the sequence, and gene loci occupy about one-third of the genome. As with the human genome, gene loci are not evenly distributed, but are clustered into sparse and dense regions. Some "giant" genes were observed that had average coding sequence sizes but were spread over genomic lengths significantly larger than those of their human orthologs. Although three-quarters of predicted human proteins have a strong match to Fugu, approximately a quarter of the human proteins had highly diverged from or had no pufferfish homologs, highlighting the extent of protein evolution in the 450 million years since teleosts and mammals diverged. Conserved linkages between Fugu and human genes indicate the preservation of chromosomal segments from the common vertebrate ancestor, but with considerable scrambling of gene order. 相似文献
80.
Preliminary Information on Feeding and Growth of Pompano, Trachinotus Ovatus (Linnaeus, 1758) (Pisces; Carangidae) in Captivity 总被引:1,自引:0,他引:1
Pero Tutman Nikša Glavić Valter Kožul Boško Skaramuca Branko Glamuzina 《Aquaculture International》2004,12(4-5):387-393
Although the chances of successfully farming Trachinotus ovatus on a commercial scale are limited by the low food conversion rates, this species deserves further applied studies on the basis of their quick adaptation to confinement and their tolerance of captivity conditions. 相似文献