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111.
《Plant Production Science》2013,16(2):185-192
Abstract

Rice productivity is related to the ability of plants to adapt to heat stress. The heat-tolerant cultivars ‘Nikomaru’ and ‘Chikushi 64’ and heat-sensitive cultivar ‘Hinohikari’ were grown at 30ºC and 25ºC for 49 days after flowering. At 30ºC, only a few white immature kernels were produced in ‘Nikomaru’ and ‘Chikushi 64’, but about 22% of grains had immature kernels in ‘Hinohikari’. The high temperature(30ºC) caused no significant changes in grain dry weight, water content, and the NMR T1 value during the early ripening stage in ‘Nikomaru’ and ‘Chikushi 64’. It also did not affect grain development, especially with respect to the nucellar epidermis, in ‘Nikomaru’ and ‘Chikushi 64’, but caused clear cessation of development of the nucellar epidermis at 14 days after flowering in ‘Hinohikari’. In addition, high temperature decreased the amylose content and increased hardnessvs. adhesion ratio of cooked rice in both ‘Nikomaru’ and ‘Chikushi 64’ resulting a softer, less sticky texture, but not in ‘Hinohikari’. The maximum viscosity and breakdown values were increased, and final viscosity decreased at 30ºC in all three cultivars. These results suggested that starch in the endosperm of grains changed from a fluid state to a doughy state more slowly in ‘Nikomaru’ and ‘Chikushi 64’ than in ‘Hinohikari’, in which the water content and NMR relaxation time decreased, and transported assimilates accumulated slowly during grain development.  相似文献   
112.
《African Zoology》2013,48(1):78-91
Photo-identification surveys over three years along 390 km of coastline north of Cape Town, revealed that Heaviside’s dolphin distribution was consistent between years and higher in areas more exposed to swells and with greater long-term availability of small hake Merluccius capensis (their principal prey). Dusky dolphin sighting rates varied considerably between years, but were generally higher in areas with lower hake availability and sandier shores (mostly straighter coastline). Large groups of 50–200 dusky dolphins were only seen in St Helena Bay, the site of a wind-driven upwelling zone. Heaviside’s dolphins were found in shallower, cooler water than dusky dolphins and were more likely to be seen during brighter phases of the moon (when nocturnal light conditions may influence the vertical migration patterns of prey) and in areas of high hake abundance. Near-shore fishing activity was higher in the northern half of the study area and clustered around harbours. Set netting occurred only at Yzerfontein and St Helena Bay, but due to changes in the industry is currently thought to be a low threat to the population. Interactions between Heaviside’s and dusky dolphins were usually neutral and sympatry appears to be mediated by differences in overall range and the type and size of prey species taken.  相似文献   
113.
赤潮研究中圆海链藻实时荧光定量PCR检测方法的建立   总被引:3,自引:0,他引:3  
何闪英  吴小刚 《水产学报》2007,31(2):193-198
为建立快速、准确的鉴定和定量检测赤潮生物的方法,以圆海链藻为例,以其18S rDNA序列为寻找种特异性引物的靶区域,通过分析18S rDNA序列,设计出适合用于RFQ-PCR的引物与探针,并通过引物PCR验证确定其特异性,进而以圆海链藻荧光定量PCR的引物和探针(Primer Thalassiosira rotula和Taqman Thalassiosira rotula),建立了定量检测圆海链藻的实时荧光定量PCR检测方法(RFQ-PCR)。与传统的显微镜计数方法比较,两者所获结果无显著性差异,证明了本方法的可行性,从而为我国沿海水域赤潮问题的研究提供了良好的技术检测途径。  相似文献   
114.
Previous experiments demonstrated that treatment of longan trees with potassium chlorate (KClO3) induces “off season floral induction” (FI) even in the absence of the naturally required cool temperature [Manochai, P., Sruamsiri, P., Wiriya-alongkorn, W., Naphrom, D., Hegele, M., Bangerth, F., 2005. Year around off season flower induction in longan (Dimocarpus longan, Lour.) trees by KClO3 applications: potentials and problems. Sci. Hortic. 104, 379–390]. Potassium chlorate, however, cannot replace the presence of functional mature leaves and sufficient light intensity. Here we examined in more detail the effect of shade (about 10% of natural sunlight) on KClO3 affected hormone concentrations/transport of leaves and shoot apical buds (SAB) and their interactions with FI.  相似文献   
115.
以农产品市场体系的基本结构为基础,分析了农产品市场体系与食品安全和农民增收之间的关系;介绍了中国农产品市场发展已经取得的成就和现存问题;最后提出了兼顾食品安全和农民增收完善农产品市场体系的措施:优化农产品市场体系的基础条件,培育不同层次不同规模的农产品交易场所,建立各农产品交易场所的有机连接,完善农产品物流配送体系,加强科技投入,政府适时、适地进行宏观调控,等等。  相似文献   
116.
以切花月季Rosa hybrida 'Samantha'为试材,通过简并引物和RACE方法从花瓣中获得了两个逆境诱导转录因子DREB家族基因全长.推定的氨基酸序列分析表明,这两个基因都具有DREB1转录因子的典型特征,因而分别命名为Rh-DREB1A和Rh-DREBIB,GenBank登录号分别为EU784069和EU784070.Rh-DREB1A和Rh-DREB1B分别包含一个编码222和231个氨基酸序列的开放阅读框.半定量RT-PCR分析结果表明,Rh-DREB1A和Rh-DREB1B在月季花瓣中能够被失水胁迫强烈诱导,但是不受乙烯诱导.由所得结果推测,这两个转录因子参与了失水胁迫诱导的信号转导途径.  相似文献   
117.
The influence of 9 rootstocks (M2, M7, M25, M26, MM104, MM106, MM109, MM111 and seedling) on fruit quality at harvest and after storage of ‘Wellspur Delicious’ (WS) and ‘Goldspur’ (GS), and of 3 rootstocks (M7, M26 and MM106) on fruit quality of ‘Red King Delicious’ (RK) and ‘Golden Delicious’ (GD) apple (Malus domestica Borkh.) was evaluated during a 4-year period. Fruits from trees on M26 were larger, developed earlier color and soluble solids (SS), and maintained higher levels of acidity (at harvest and during storage) in comparison with other rootstocks. Fruit from trees on M2 tended to have high SS. Fruit color from trees on MM104, MM106 and MM109 tended to be comparatively poor. There were significant rootstock effects on SS, starch, acidity, color, circumference, weight and box size.  相似文献   
118.
《三国志》裴松之注因为引用了几则具有志怪性质的材料,而被历来史家批评其“凿空语怪”、“坐长烦芜”。事实上,裴松之在引援这些注文时并非是不加选汰而盲目采用的。裴松之用审慎的态度和隐蔽的手段,把自己对历史人物及事实的评价暗蕴于注解之中。而且,其保存小说材料和用小说注史之功,是不可泯没的。《三国志》裴松之注将历史与小说相结合,则对当下的玄幻小说创作具有一定的启迪意义。  相似文献   
119.
泗阳县世行二期项目于1998~2002年实施,总投资6323万元。其中,世行贷款2020万元,地方财政配套2036万元,群众自筹2267万元。改造中低产田15333hm^2,受益人口19.3万人。项目区农业综合生产能力显著提高,产业结构得到科学合理优化。取得了良好的社会、经济及生态效益。  相似文献   
120.
一家一户的家庭经营有其自身的弱点,难以抵御“两个风险”,发展农村合作组织是提高农民组织化程度,增强农民抗御“两个风险”能力,加快农业结构调整,实现农民收入稳定增长的客观要求和必然选择。目前,我国农村合作组织中仍然存在着资产不清、产权不明、管理混乱、管理队伍素质较低等一系列问题。新形势下我国农村合作组织发展需要在转变观念的基础上,因地制宜的采取切实有效的措施。  相似文献   
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