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1.
ＩＮＴＲＯＤＵＣＴＩＯＮＭａｔＲｕｓｈ (ＪｕｎｃｕｓｅｆｆｕｓｕｓＬ .Ｖａｒ.Ｄｅｃｉｐｉ ｅｎｓＢｃｈｅｎ)ｉｓａｐｅｒｅｎｎｉａｌｈｅｒｂａｃｅｏｕｓｒｏｏｔｐｌａｎｔ,ｗｈｏｓｅｓｔｅｍｉｓｕｓｅｄａｓｒａｗｍａｔｅｒｉａｌｆｏｒｗｏｖｅｎｓｔｒａｗｍａｔｓ,ｓｅａｔｓａｎｄｈａｔｓ.ＩｎＺｈｅｊｉａｎｇａｎｄＪｉａｎｇｓｕＰｒｏｖｉｎｃｅｓ,Ｃｈｉｎａ,ｉｔｉｓｔｒａｎｓｐｌａｎｔｅｄｉｎｔｈｅｍｉｄｄｌｅｏｆＮｏｖｅｍｂｅｒａｎｄｈａｒｖｅｓｔｅｄｉｎｅａｒｌｙＪｕｎｅｎｅｘｔｙｅａｒ.Ａｍｏ… 相似文献
2.
Shades of different light intensities (29%, 43%, 54%, 60% or 68%) along with control (no shade) were studied to observe their
effects on the flowering time and plant quality. A hyperbolic relationship was observed between different light intensities
under shade, and time to flowering. The total number of flower buds showed a curvilinear relationship with light intensities.
Growth parameters related to the plant characteristics such as plant height, leaf area and plant fresh weight were improved
under shading treatments at the expense of flowering time and number of flower buds. However, both linear and polynomial models
applied assumed that cultivar Chimes White was equally sensitive to light intensity throughout development. 相似文献
3.
杂交水稻华优63后期施氮肥,其穗部和叶片干物重增加,叶鞘和茎秆的干物质运转加快。叶片干重以花前施氮的最高。花前施氮钾,开花期叶鞘干重降低较多;灌浆末期至黄熟期和收割期叶鞘干重下降,分别以花后施氮和花前施氮钾下降也较多。开花期茎秆干重,以花前施氮下降明显,灌浆末期至黄熟期和收割期分别以花后施氮和花前施氮钾降低明显。穗部干重以花后施氮的最高。因此,华优63以花后追施氮肥为好,稻穗增重速度较快,产量较高。文中讨论了水稻生育后期施肥的一些原理和原则,关键在于促进叶片衰退缓慢,茎叶贮存物质迅速向谷粒运输,茎叶不徒长,谷粒产量高。 相似文献
4.
MUNIR Muhammad JAMIL Muhammad BALOCH Jalal-ud-din KHATTAK Khalid Rehman 《Journal of Zhejiang University. Science. B》2004,(4)
INTRODUCTIONManyangiospermsflowerataboutthesametimeeveryyear.Thisoccurseventhoughtheymayhavestartedgrowingatdifferenttimes.Theirfloweringisaresponsetothechanginglengthofdayandnightastheseasonprogresses.Intheearly20thcentury,amutationintobaccocultivarMary-landMammothwasdiscoveredthatpreventedtheplantfromfloweringinthesummerasnormalto-baccoplantsdo.慚arylandMammoth?wouldnotbloomuntillateDecember(GarnerandAllard,1920).Thisreflectedtheeffectofphotoperiodonflowering.Afterwards,onthebasisofl… 相似文献
5.
不同光照强度对薇甘菊幼苗生长和形态的影响 总被引：13，自引：0，他引：13
比较了生长在不同光照强度下的薇甘菊 (Mikainamicrantha) 幼苗的生长型。结果表明 :苗高、节间长、比叶面积、叶面积比、总叶面积、净同化速率、支持结构生物量比、根生物量比和根冠比随着光照强度的变化而改变 ;然而 ,比茎长、比叶柄长、总生物量、相对生长速率和叶片生物量比却保持相对的稳定。说明薇甘菊幼苗对不同的光强梯度具有不同的可塑性和适应性。 相似文献
6.
应用植物离体快繁培养技术研究凤尾鸡冠瓶苗开花技术,结果表明:凤尾鸡冠的种子用0.1%的HgCl2灭菌8 min效果最好,成活率达到90%;最佳的增殖培养基配方为MS+NAA 0.1 mg·L-1+6-BA 1.0 mg·L-1+蔗糖20 g·L-1+琼脂10 g·L-1;经过壮苗后的植株在MS+PP3330.5 mg·L-1+NAA 0.01 mg·L-1+蔗糖20 g·L-1+琼脂10g·L-1培养基上培养,开花率最高,为81%;适当减少MS培养基中氮含量,能提高凤尾鸡冠瓶苗开花率;光照强度为3 000 Lx时,瓶苗开花率最高。 相似文献
7.
Shades of different light intensities (29%, 43%, 54%, 60% or 68%) along with control (no shade) were studied to observe their effects on the flowering time and plant quality. A hyperbolic relationship was observed between different light intensities under shade, and time to flowering. The total number of flower buds showed a curvilinear relationship with light intensities. Growth parameters related to the plant characteristics such as plant height, leaf area and plant fresh weight were improved under shading treatments at the expense of flowering time and number of flower buds. However, both linear and polynomial models applied assumed that cultivar Chimes White was equally sensitive to light intensity throughout development. 相似文献
8.
目的:测定槐角中多糖的含量及其多糖水解物中单糖。方法:利用分光光度法测定槐角多糖含量。利用三氟乙酸制备多糖水解物,采用毛细管电泳-安培检测槐角多糖水解物中单糖。结果:槐角中多糖的含量为3.12%。槐角多糖水解物中含有果糖和葡萄糖,两者的摩尔比为34.2∶1。结论:该方法准确、简便,可用于槐角中多糖及其多糖水解物中单糖的检测。 相似文献
9.
An experiment was carried out to examine the effects of light quality on the growth and development of antirrhinum under three different temperatures 19℃, 24℃ and 27℃ in glasshouses. Five different colour filters (i.e. 'Red absorbing', 'Blue absorbing', 'Blue and Red absorbing' and two 'partially Blue absorbing' materials) were 相似文献
10.
杂交稻威优64在开花前或开花后6～7天追施氮肥或氮钾肥,可使开花期、灌浆末期至黄熟初期和收割期的叶片和穗部干物重增加,促进叶鞘和茎秆的干物质运转,但不同施肥处理对不同器官有不同影响。花前施氮钾,叶片干重从开花期到灌浆末期至黄熟初期明显增高,收割期以花前施氮和花后施氮钾效果明显。花前施氮使威优64开花期叶鞘和茎秆干重明显降低。花后施氮钾处理的穗部干物重最高。表明威优64以花前后施(氮)肥、且以氮加钾效果最佳。 相似文献
11.
Genetic analysis of fruit shape traits at different maturation stages in sponge gourd 总被引：5，自引：0，他引：5
The fruit shape is important quantitative trait closely related to the fruit quality. However, the genetic model of fruit shapes has not been proposed. Therefore, in the present study, analysis of genetic effects for fruit shape traits （fruit length and fruit perimeter） in sponge gourd was conducted by employing a developmental genetic model including fruit direct effects and maternal effects. Analysis approaches of unconditional and conditional variances were applied to evaluate the genetic behavior of fruit shape traits at economical and physiological maturation times. The results of variance analysis indicated that fruit length and fruit perimeter were simultaneously affected by fruit direct genetic effects and maternal effects. Fruit direct genetic effects were relatively more important for fruit shape traits at whole developmental period. The gene expression was most active at the economical maturation stage （1-12 d after flowering） for two shape traits, and the activation of gene was mostly due to direct dominance effects at physiological maturation stage （13-60 datter flowering）. The coefficients due to different genetic effects, as well as the phenotypic correlation coefficients, varied significantly between fruit shape traits themselves at various maturation stages. The results showed that it was relatively easy to improve fruit shape traits for industrial purpose by carefully selecting the parents at economical maturation stage instead of that at physiological maturation stage. 相似文献
12.
在田间试验条件下研究了施肥对“秦油二号”杂交油菜氮、磷、钾营养及其产量的影响,结果表明:单施氮肥,增加植株氮、磷、钾吸收强度和植株含氮浓度,但对植株磷、钾浓度无明显影响。氮磷配施既能显著提高植株氮、磷、钾吸收强度,也能增加植株氮、磷、钾浓度。在施用氮、磷肥料基础上配施氯化钾肥,降低了植株氮、磷吸收强度和氮浓度。施肥使油菜氮,磷营养吸收高峰推迟。吸氮高峰期在油菜苔期,吸磷高峰期在油菜花角期。在本试验条件下,氮肥与磷肥配合施用油菜产量和经济效益最高,比单施氮肥增产23.2％,比氮磷钾配施增产11.4％,每亩增收三十无以上。 相似文献
13.
SH波在正交各向异性功能梯度材料直裂纹处的散射 总被引：2，自引：0，他引：2
研究了正交各向异性功能梯度材料中直裂纹对SH波的散射问题,材料两个方向的剪切模量和密度假定为指数模型,通过积分变换-积分方程方法,建立数学模型,化为对偶积分方程,用Copson方法求解对偶积分方程,最后得到动应力强度因子,并且给出了数值算例,讨论了在SH波作用下,裂纹尖端的动应力强度因子与入射波的频率,入射角的关系． 相似文献
14.
DeSena AD Murphy RA Douglas-Palumberi H Blau G Kelly B Horwitz SM Kaufman J 《Child abuse & neglect》2005,29(6):627-643
OBJECTIVE: To evaluate the SAFE Homes (SH) program, a short-term group care program for children between 3 and 12 years of age who enter care for the first time. The program aims to improve case outcomes by consolidating resources to facilitate assessment and treatment planning. METHODS: The 1-year outcomes of 342 children who received SAFE Home services and 342 matched foster care (FC) control children were compared. The 684 subjects used in this report were selected from a larger pool of 909 subjects using propensity score matching to control for hidden bias in treatment group assignment. We hypothesized that SAFE Homes would result in greater continuity of care for children (e.g., fewer placements, more placements with siblings and in towns of origin), identification of more relatives for substitute care when needed, reduced use of high-cost restrictive care settings (e.g., residential, inpatient), and reduced rates of re-abuse through earlier detection and provision of services to meet child and family treatment needs. RESULTS: Prior to the initiation of the SAFE Homes program, 75% of the children who entered care in the State experienced three or more placements in the first year. The outcomes of both the SH and FC cases were significantly improved over pre-SAFE Home State statistics. The FC group, however, had comparable or better outcomes on most variables examined. In addition, the total cost for out-of-home care for the children in FC was significantly less, despite the fact that the two groups spent similar amounts of time in care (average time in care: 7 months). This finding held when the total placement cost was calculated using the State reimbursement rate of 206.00 US dollars per day for SAFE Home care (SH: 20,851 US dollars +/- 24,231 US dollars; FC: 8,441 US dollars +/- 21,126 US dollars, p < .001), and a conservative SAFE Home program fee of 85.00 US dollars per day that only considered the child care and custodial staffing costs uniquely associated with the program (SH: 13,314 US dollars +/- 21,718 US dollars; FC: 8,441 US dollars +/-21,126 US dollars, p < .001). CONCLUSION: Improvements in outcomes related to continuity of care can be attained through staff training. The SAFE Home model of care is not cost-effective for first-time placements. 相似文献
15.
以2年龄桐花树(Aegiceras corniculatum)为试验材料,研究了不同光照强度[全光照(Ac100)、75%光照(Ac75)、45%光照(Ac48)、20%光照(Ac20)]对桐花树根系生长和根系活力的影响.结果表明,处理360d后,随着光照强度的减弱,桐花树的根生物量和根冠比均呈显著下降的趋势,其中Ac100的根生物量和根冠比最大,分别是Ac25的15.42倍和2.08倍;营养根和贮气根的根数、根长和根直径均呈逐渐递减的趋势,Ac100的营养根根数和根长显著高于其他处理,其中Ac100的营养根和贮气根的根数、根长分别是Ac25的3.85、1.37倍和14.59、1.68倍;根系含水量呈上升趋势,其在6月份最高,冬春季最低;而根系活力则呈下降趋势,其在冬春季呈下降趋势,在夏秋季呈先升后降的趋势.试验表明,不同光照强度对桐花树根系生长和根系活力有显著影响,在100%光照强度下其根系发达,根系活力较高.而在25%光照强度(过度遮光)下不利于根系生长,且桐花树能适应一定程度的遮荫环境. 相似文献
16.
We tested a California sea lion for visual oddity learning by presenting problems composed of three two-dimensional black-and-white
stimuli, two identical (S−) and one different (S+). In the first experimental stage, a single problem per session was presented
until learning criterion was reached. In the second experimental stage, all problems were presented only five times in succession;
then a new problem was introduced (six problems/session). In the third experimental stage, each problem was presented only
once. The sea lion mastered all stages of oddity learning. A final transfer test with oddity problems composed of completely
new stimuli yielded performance significantly above chance. Data analyses suggested learning of specific stimulus properties
in the first stage, learning set formation in the second stage, but oddity conceptualization in the third stage. 相似文献
17.
Hans Joachim Schlichting 《International Journal of Science Education》2013,35(2):157-168
The Science Foundation Programme (SFP) was launched in 1991 at the University of Natal, Pietermaritzburg, South Africa in an attempt to equip a selected number of matriculants from historically disadvantaged schools with the skills, resources and self-confidence needed to embark on their tertiary studies. Previous research within the SFP biology component suggests that a major contributor to poor achievement and low retention rates among English second language (ESL) students in the Life Sciences is the inadequate background knowledge in natural history. In this study, SFP student background knowledge was assessed along a continuum of language dependency using a set of three probes. Improved student performance in each of the respective assessments examined the extent to which a sound natural history background facilitated meaningful learning relative to ESL proficiency. Student profiles and attitudes to biology were also examined. Results indicated that students did not perceive language to be a problem in biology. However, analysis of the student performance in the assessment probes indicated that, although the marine course provided the students with the background knowledge that they were initially lacking, they continued to perform better in the drawing and MCQ tools in the post-tests, suggesting that it is their inability to express themselves in the written form that hampers their development. These results have implications for curriculum development within the constructivist framework of the SFP. 相似文献
18.
通过研究天门冬可溶性糖、氨基酸和皂苷等主要营养物质的月变化规律,并结合气象资料,探讨天门冬较佳采摘时间和适宜栽培的气候条件．研究发现,皂苷的含量在1月和12月较高,氨基酸的含量在6月较高,可溶性糖的含量在1月、2月和11月较高．结果表明,不同营养物质在不同月份积累的量不同,其适宜的采收时间也不一样,且较低的温度适宜天门冬营养物质的积累． 相似文献
19.
对春季不同覆盖层次下温度、植株干重的测定表明:不同覆盖层次下温度变化由高到低依次为:三层覆盖＞二层+草＞二层覆盖＞一层覆盖;光照强度强弱的变化为一层覆盖＞二层覆盖＞二层+草＞三层覆盖;随着覆盖层次的不断增加,植株高度不断增加,茎粗不断减小;植株干重的变化为在苗生长初期以二层覆盖和二层+草覆盖方式下最大,后期则以一层覆盖的植株干重最大;在叶绿素方面,蔬菜种类不同,其变化呈现各自不同的规律. 相似文献
20.
在气体样品池条件下,用调频半导体激光器激发Rb原子至Rb（sPj）态,通过测量样品池前后光强比,得到不同温度下样品的吸收系数。对于Rb（5S1/2→5Pj）的跃迁,可获得g2／g1值和5Pj的寿命值（我们取j=1／2,即用D1线794nm计算）,从而得出不同温度下样品的基态原子密度．实验结果表明：基态原子的密度N随着温度的升高而增大．通过与其它实验结果进行比较,得出在低温下的数据比较准确,可见利用光学吸收方法测量低激发态原子密度较为理想． 相似文献