水稻芽期耐冷性与其他耐冷性状的相关关系

以籼粳交“密阳23/吉冷1号”的F3系统群为试材,探讨了水稻芽期耐冷性遗传变异以及与其他耐冷性状的相关关系。结果表明,F3系统群的芽期耐冷性表现为近似正态的连续分布,是由多基因控制的数量性状。在自然低温或冷水处理下水稻幼苗生长能力、抽穗天数、穗抽出度、孕穗期耐冷性(低温下结实率)和成熟期综合耐冷性等性状均与芽     

水稻主要农艺性状的冷水反应遗传分析

利用10个水稻品种配制45个半双列杂交组合,并在冷水处理下探讨了水稻主要农艺性状的冷水反应差异、配合力和遗传参数,以及冷水反应指数间的相关关系。研究表明,抽穗天数、秆长、穗长、穗粒数、结实率和穗颈长等农艺性状冷水反应的一般配合力和特殊配合力均呈显著,且一般配合力的变异大于特殊配合力的变异;水稻品种的冷水反应有着明显的差异,其中通88 7、高产102和TR22183等品种的冷水反应较迟钝,并对主要农艺性状的冷水反应指数（CRI）具有较高的一般配合力。亲本中控制秆长及其CRI值的正、负等位基因的频率基本相等,显隐性基因频率基本相同;秆长的表现型值及其CRI值受少数主效基因控制,具有较高的狭义遗传力。穗粒数、穗颈长和结实率及其CRI值与秆长的CRI值呈显著正相关,结实率的CRI值与穗颈长的CRI值呈显著的正相关。     

水稻氮素利用效率的选择效果

利用“Dasanbyeo/IR66746-26-3-2”和“TR22183/IR66167-27-5-6”两个杂交组合探讨了在施氮和未施氮条件下杂交早期世代对产量及氮素利用效率的选择效果。研究结果表明,在杂交早期世代对产量的直接选择效果在未施氮条件下明显高于施氮条件下,并通过产量选择对氮素利用效率进行间接选择无论在施氮区还是未施氮区均有显著效果     

Identification of regulated proteins by resveratrol in glutamate-induced cortical injury of newborn rats

Glutamate induces neuronal damage by generating oxidative stress and neurotoxicities. The neurological damage caused by glutamate is more severe during brain development in newborns than in adults. Resveratrol is naturally present in a variety of fruits and medicinal plants and exerts a neuroprotective effect against brain damage. The goal of this study was to evaluate the neuroprotective effects of resveratrol and to identify changed proteins in response to resveratrol treatment during glutamate-induced neonatal cortical damage. Sprague-Dawley rat pups (7 days old) were randomly divided into vehicle, resveratrol, glutamate, and glutamate and resveratrol groups. The animals were intraperitoneally injected with glutamate (10 mg/kg) and/or resveratrol (20 mg/kg) and their brain tissue was collected 4 hr after drug administration. Glutamate exposure caused severe histopathological changes, while resveratrol attenuated this damage. We identified regulated proteins by resveratrol in glutamate-induced cortical damaged tissue using two-dimensional gel electrophoresis and mass spectrometry. Among identified proteins, we focused on eukaryotic initiation factor 4A2, γ-enolase, protein phosphatase 2A subunit B, and isocitrate dehydrogenase. These proteins decreased in the glutamate-treated group, whereas the combination treatment of glutamate and resveratrol attenuated these protein reductions. These proteins are anti-oxidant proteins and anti-apoptotic proteins. These results suggest that glutamate induces brain cortical damage in newborns; resveratrol exerts a neuroprotective effect by controlling expression of various proteins with anti-oxidant and anti-apoptotic functions.     

Contagious ecthyma in the live sheep export industry

Objective: To investigate control options for contagious ecthyma (scabby mouth) in Australian sheep exported live to the Middle East.
Design: Prevalence, vaccination and modelling studies.
Procedure: One hundred and forty weaner sheep (less than 1 year old) on each of 106 farms in Western Australia (WA) and 18 farm groups of adult wethers received at a WA commercial feedlot were examined for lesions of scabby mouth. Sheep on a total of 26 farms in 3 States were divided into treatment and control groups for the vaccination study. A simple deterministic compartmental model was developed to establish which parameters had the greater effect on disease prevalence.
Results: The proportion of farms with evidence of scabby mouth in weaner sheep was 23.6% and, on those farms with the disease, the overall prevalence was 6.1%. At the feedlot, 4 out of 18 farm groups had 5 or more sheep with lesions on arrival. The overall prevalence in the 4 diseased groups was 5.2%. Sheep vaccinated on farm before trucking to the feed-lot had a lower prevalence of scabby mouth at the end of simulated shipping than controls. The main determinant of scabby mouth prevalence was the proportion of sheep immune to the disease.
Conclusion: A program of vaccination for scabby mouth will reduce the prevalence of disease during live export. However, using current technology it is not possible to deliver shipments of sheep to the Middle East that are guaranteed completely free of scabby mouth.     

Sacrocaudal agenesis in a Korean native calf (Bos Taurus Coreanae)

A male deformed Korean native calf was examined macroscopically. The deformed calf had no caudal vertebral columns from 5th lumbar vertebra, sacrum and coccygeal vertebrae. The spinal cord was terminated in the vertebral foramen of the 3rd lumbar vertebra. The cervical vertebrae had scoliosis and the 3rd and 4th cervical vertebrae were fused. The 2nd and 3rd lumbar vertebrae were fused and the left and right transverse processes of the 4th lumbar vertebra articulated with ala of the ilium. The rectum was greatly expanded by the imperforate anus and a rectourethral fistula was formed between the rectum and urethra. The deformed calf was recorded as a first documentation of sacrocaudal agenesis confirmed in a Korean native calf.     

Ethanol decreases the expression of pituitary adenylate cyclase activating polypeptide in rat testes

The present study was designed to evaluate the effect of ethanol on pituitary adenylate cyclase activating polypeptide (PACAP) expression in adult rat testes. Ethanol (3 g/kg i.p., 15% v/v in saline) was administrated to adult male rats for 10 days. Using northern blot analysis, we elucidated the decrease of PACAP mRNA in rat testes by ethanol administration. The level of PACAP mRNA was decreased by 46.5% in testes of the ethanol-treated animals, compared to that of saline-treated animals. In particular, ethanol exposure decreased the expression of PACAP mRNA and protein in developing germ cells, which are sperm cell progenitors. Thus, our findings suggest that the decrease of PACAP in developing germ cells by ethanol administration may contribute to the suppression of male reproductive activity.     

Ethanol exposure decreases cell proliferation and increases apoptosis in rat testes

Ethanol exposure is known to suppress male reproductive activity in laboratory animals and humans. The present study was designed to evaluate whether chronic ethanol exposure decreases proliferative activity or increases apoptosis in the testes. Ethanol (1.5 g/kg or 3 g/kg i.p., 15% v/v in saline) was administrated to adult male rats for 10 days. Proliferating cell nuclear antigen (PCNA) was used as a proliferative marker. Western blot analysis showed that ethanol administration significantly reduced the level of PCNA. Also, immunoreactivity of PCNA-positive cells in the spermatogonia and primary spermatocytes were decreased by ethanol exposure. However, the number of TUNEL-positive cells was significantly increased in the testicular germ cells of ethanol-treated rats. Moreover, ethanol administration significantly increased the level of activated caspase-3 in testes. In conclusion, our findings suggest that ethanol may partly contribute to the suppression of male reproductive activity through a reduction of cell proliferation and an enhancement of cell death in rat testes.     

Differential Response of Grain Quality to Cold Water Irrigation in Cold Tolerant and Sensitive Lines of Rice

Three rice varieties and several F3 lines with high and low cold tolerance, selected from F3 segregation lines of two crosses Milyang 23/Tong 88-7 and Milyang 23/TR22183 were used to analyze the effects of cold tolerance on the response of grain quality to cold water irrigation. The result showed that cold water irrigation led to the decrease of rice grain size. The length, length-width ratio and weight of brown rice grain were more sensitively affected by cold water irrigation than the width and thickness. The shape of brown rice grain was not significantly affected by the selection for cold tolerance at the seedling stage (CTS). The gel consistency, amylose content, peak viscosity, cool viscosity, breakdown viscosity and consistency viscosity were decreased, while alkali digestibility value and protein content were increased by cold water irrigation. Under normal irrigation condition the physicochemical properties of milled rice and viscogram components of milled rice flour were not significantly different between lines with high and low cold tolerance. Under cold water irrigation the amylose content, peak viscosity, hot viscosity, final viscosity of rice lines with high CTS or high cold tolerance at the booting stage (CTB) were higher, while the protein content, setback viscosity, breakdown ratio and setback ratio were lower, than those of rice lines with low cold tolerance. This implied that the cold water response of rice grain quality was less sensitive in the lines with high cold tolerance than in the lines with low cold tolerance, and the varietal improvement for cold tolerance would be important for grain quality improvement at the same time.     

水稻芽期耐冷性QTL的分子定位

 以籼粳交密阳23号/吉冷1号的F2：3 代200个家系作为作图群体，构建了一张含有97个微卫星 （SSR）标记的分子连锁图谱。在5℃低温条件下，对F3家系进行芽期耐冷性鉴定，并利用SSR标记进行了芽期耐冷性数量性状位点（QTL）分析。研究结果表明，芽期耐冷性在F3家系群中呈单峰连续分布，表现为由多基因控制的数量性状；共检测到与芽期耐冷性有关的QTL 3个，分别位于第2、4 和7染色体上，对表型变异的贡献率范围为11.5%～20.5%。其中，位于第4染色体RM273～RM303的qCTBP4对表型变异的贡献率最大。