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101.
Chinese chive is produced year-round in Japan, therefore it is important to demonstrate the relationships of short-day (SD) conditions with flower stalk elongation and flower formation for optimizing the cropping system, e.g. the increase in harvests per year. To clarify the influence of short photoperiod on flower stalk elongation and flower formation in Chinese chive, 8 h SD treatments were applied at different developmental stages of flower stalk elongation and flower formation. When the SD treatment started from vegetative or floral-initiated stages, the earlier the SD treatment started, the fewer flower stalks appeared. Also, the earlier the SD treatment started, the less the flowers bloomed and the more the flower stalk elongation was inhibited at the end of SD treatments. Many involucres did not open and withered with death of florets in SD when the SD treatment started between the umbel or flower bud differentiation and the perianth to stamen-formation stages. Also, all or part of the florets aborted and there were no complete inflorescences in the later SD treatments. We found that, in Chinese chive, the development of flower stalk elongation and flower formation were inhibited with the earlier SD treatment, after vegetative or floral-initiated stages. Furthermore, it is considered that Chinese chive needs long-day (LD) for the flower stalk elongation and inflorescence formation after the initiation of the flower bud. The plant has a qualitative LD requirement with the same photoperiodic requirement for both flower bud initiation and flower development.  相似文献   
102.
利用NCBI和Phytozome数据库进行GmIDD基因的同源基因检索,获取该基因在大豆不同染色体中5个拷贝的序列信息。通过对功能结构域的分析结果显示GmIDD基因5个拷贝均含有2个C2H2型(72~92 aa、114~142 aa)、2个C2HC型(149~169 aa、176~195 aa)锌指结构域。GmIDD基因cDNA序列全长为1 227 bp,编码408个氨基酸。系统进化树分析结果显示GmIDD基因5个拷贝中除了Glyma.14g10940和Glyma.17G228000外,其它IDD蛋白间进化距离较远,表明不同大豆IDD基因在功能上可能存在一定差异。长短日照处理下GmIDD表达量的分析结果显示GmIDD基因受短日照诱导表达,因此推测GmIDD可能参与大豆开花的调控过程。  相似文献   
103.
The aim of this study was to assess initial effects of warming on the nutrient pools of carbon and nitrogen of two most widespread ecosystem types, swamp meadow and alpine meadow, in the Qinghai-Tibet Plateau, China. The temperature of the air and upper-soil layer was passively increased using open-top chambers (OTCs) with two different temperature elevations. We analyzed air and soil temperature, soil moisture, biomass, microbial biomass, and nutrient dynamics after 2 years of warming. The use of OTCs clearly raised temperature and decreased soil moisture. The aboveground plant and root biomass increased in all OTCs in two meadows. A small temperature increase in OTCs resulted in swamp meadow acting as a net carbon sink and alpine meadow as a net source, and further warming intensified this processes, at least in a short term. On balance, the alpine ecosystems in the Fenghuoshan region acted as a carbon source.  相似文献   
104.
王敏  李万志 《安徽农业科学》2013,(32):12658-12661
利用常规气象资料、NCEP再分析资料和卫星资料,对青海2006~2010年2、6和6h以上3个时段短时强降水(1h≥25mm)天气过程的环境场和物理量进行了诊断分析。结果表明,多发区在青海南部和东部,7和8月为峰值区;6h以下时段内强降水发生的主要触发机制是中尺度低压和辐合线、干线,而6h以上是短波槽和切变线;强降水发生前,500hPa有强的水汽辐合,相对湿度大,有强烈的垂直上升运动;中低层风场的垂直风切变强,且风随高度顺转,发生在6h内的短时强降水天气的垂直风切变最弱,  相似文献   
105.
本分析标准在原木检尺进舍办法上存在的不合理问题。探讨短径进舍和平均径进舍的合理界限。提出了“以增量短径进舍为检尺径”的新的检尺径进舍办法。  相似文献   
106.
Diarrhea is considered to be associated with microbial dysbiosis caused by infection of pathogens but poorly understood. We herein characterized the colonic microbiota of diarrheal early-weaning piglets infected with porcine circovirus type 2 (PCV2) and Campylobacter. Campylobacter infection significantly decreased species richness and Shannon diversity index of colonic microbiota together with a significant increase in the proportion of Campylobacter and Enterobacteriaceae, whereas no significant difference on the above indexes was observed in piglets infected with PCV2 compared with healthy piglets. PCV2 and Campylobacter infection could disturb the homeostasis of colonic microbiota through deterioration of ecological network within microbial community, and specially Campylobacter performed as a module hub in ecological networks. The microbial dysbiosis caused metabolic dysfunction and led to a remarkable reduction in production of short chain fatty acids, following by a higher pH level in colon cavity. Campylobacter infection disturbed the function of colonic tract barrier observed in terms of significant lower relative expression of claudin-1, occluding, and zonula occludens protein-1 genes, and PCV2 infection induced intestinal inflammation together with a higher permeability of colon. Generally, these results suggested that PCV2 and Campylobacter infection could induce microbial dysbiosis and metabolic dysfunction, and cause intestinal disorder, all of which finally were associated to contribute to the diarrhea of early-weaning piglets.  相似文献   
107.
优质高产杉木新良种选育及高效栽培模式的研究   总被引:4,自引:2,他引:2  
在长江下游江苏南部沿江宁镇低丘地区研究表明 ,杉木建筑材的主要物理力学性状与木材基本密度紧密相关。木材基本密度在种源、家系、杂交组合子代间有明显的遗传差异 ,而与生长 (材积生长 )无明显的负遗传制约关系。因此 ,可按“生长、材性两个阶段独立选择法”进行生长与材性联合改良。经试验研究 ,选出了亚林 1、亚林 2、林朵 8、林朵 7、林朵 2 5、湘 2等 6个优质高产杉木优良家系 ,它们在 8a时材积比对照 (广西融水种源 )高出 11 4 %~39 8% ,木材基本密度提高了 1 2 9%~ 8 76 % ;选出林朵 19、湘 2等两个生长与对照相近 ,但材质优良的家系 ,木材基本密度比对照高 7 33%~ 10 97%。选出的这些优质高产杉木优良家系可按短轮伐期用材林栽培模式和短轮伐期材、苗 (观赏苗木 )复合栽培模式推广应用 ,能获得较高的经济效益  相似文献   
108.
在分析“短青春期”品种对播季反应的基础上,通过比较不同品种出苗至开花数与开花至成熟天数对短日处理的反应,以进一步明确夏大豆型“短青春期”品种的光(温)敏感性特征。研究结果表明:春播条件下,开花前短光照处理,“短青春期”品种中豆24和巨丰出苗至开花天数仅缩短2-14d,敏感度较小,与春大豆型品种相似,而与典型夏大豆品种,秋大豆品种和“长青春期”品种明显不同,中豆24和巨丰的出苗至开花天数对短光照不敏感。同为“短青春期”品种的中豆24和巨丰,其开花至成熟天数对短日处理的反应有明显差异,并者与春大豆相似,而后者的开花至成熟天数的短日照敏感不仅大于复大豆,而且也大于秋大豆。生育前期对短日照不敏感的品种,其短日处理效应在生育后期表现更加明显。本文还讨论了不同品种短日处理后效应的传递特征。  相似文献   
109.
设计了一种小型的双频微带天线,使用曲流技术、双谐振模式分别实现了天线的小型化和双频带工作。对天线的仿真及测试结果表明,天线工作在2.4 GHz频段和5.8 GHz频段,且在两个频段上具有较一致的良好的辐射特性,二者的相对带宽分别是1.38%和3.94%。  相似文献   
110.
It is well established that inulin-type fructans, such as oligofructose derived from chicory root, improve gastrointestinal health via fermentation and proliferation of desirable bacteria in the large bowel. However, differences in fructan structure may contribute significantly to different fermentation and subsequent metabolic effects. Here we ascertain the chain length of two novel cereal fructans (graminan) isolated from wheat stem and barley grain, and investigate their fermentation capacity in vitro, in comparison to inulin and oligofructose. Fractions, representing three predominant fructo-oligosaccharide (FOS) size ranges from each source, were fermented and short chain fatty acids (SCFA) production was measured after 24 h of batch culture. Graminan FOS when fermented produced similar levels of total SCFA as oligofructose and inulin. The fermentation of high DP FOS fractions of barley grain and wheat stem (DP 5–15) produced more propionate than oligofructose. Graminan fructans may provide a useful alternative source of oligofructose with potential additional health benefits.  相似文献   
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