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1.
不同密度下地膜甜菜光合、呼吸特性及其与产、质量间相关性的研究 总被引:1,自引:1,他引:0
研究了不同密度群体结构下,地膜甜菜光合及呼吸作用的日变化,不同生育期光合、呼吸作用的变化及与产量和经济性状间的相关性。结果表明:低到中等密度下(45000~75000株·hm-2)群体光合、呼吸作用日变化为双峰曲线,高密度下(105000株·hm-2)为单峰曲线。中-高密度下,群体表观光合强度和呼吸强度日变化均为单峰曲线。密度越大,随生育期推进,表观光合强度下降越明显,而净光合强度则大幅度降低。密度较高,个体的生长受到显著抑制,单位面积的生物学产量明显增加。密度过大导致单根重大幅度下降,含糖量降低,产糖量反而下降。相关分析表明,地膜甜菜群体光合、呼吸作用与甜菜个体生长相关性较好而与群体含糖率、产粮糖量间相关性较差,与地上部生长相关性较好而与根部生长相关性较差。三项指标中,呼吸作用、表观光合强度与作物生长相关性好而净光合强度只与单根重有较好相关性。 相似文献
2.
在田间自然条件下,研究了北疆高产棉花(2250kg·hm-2)群体光合速率、呼吸速率的变化及与产量之间的关系。结果表明,公顷产2250kg高产棉花群体光合速率在整个生育期的变化呈单峰型曲线,在盛花期以前稳定上升,至盛铃期达最大,值为4.05gCO2·m-2·h-1,吐絮期尚保持较高水平。全生育期平均值为2.63gCO2·m-2·h-1。群体呼吸速率随生育时期的变化亦呈现单峰曲线,在盛铃期达最大值。值为2.69gCO2·m-2·h-1,群体呼吸速率的最大值出现时期较群体光合速率晚15~20天左右。群体光合速率的日变化呈现单峰型曲线。至中午14:00~15:00达最大值。群体呼吸速率日变化的趋势与光合相似,但其最大值较群体光合速率晚出现1h左右。盛花结铃期和吐絮期群体光合速率与皮棉产量呈显著正相关。群体呼吸速率与叶面积指数、干物质重之间的盛花期和吐絮期呈显著正相关,与经济产量也呈正相关,但未达显著水平。 相似文献
3.
通过“新甜二号”块根三生构造的形成及发育过程观察看出:甜菜块根三生构造的形成始于一对真叶期,从二对真叶到块根糖分增长期前期是块根三生维管束环的主要形成时期。块根内对三生维管束环上的三生维管束束数随块根三生维管束环数的增加而增加,二者之间里显著的直线相关。而且块根内的三生维管束环数及环上的束数都具有极限性。块根最外2—3环上的三生维管束束数虽多,但成熟的较少。块根内各环间距随三生维管束环数的增加而呈动态变化,环间距增长最快在叶丛繁茂中期到块根糖分增长期中后期。生育后期,根内以第三环间距最大,而且根内各环间距的大小与环数之间呈Y=ae~(bx)·x的函数关系。 相似文献
4.
盐碱荒地膜下滴灌种植甜菜,冠/根比平衡点较常规灌提前15天以上。收获时,随施氮量的增加块根干物质呈递增趋势。叶丛氮代谢有2个高峰:苗期(6月4日,主要)和块根糖分增长末期(8月24日);块根氮代谢的变化与叶丛相似。植株对氮吸收量与施氮量呈正相关(R=0.9968);高氮处理的甜菜生育后期地上部氮分配率仍较高,不利于块根增长和糖分积累,甜叶片硝酸还原活性总体上随生育进程而提高,至7月28日左右达最大值,而后减弱,说明甜菜氮的吸收与同化以生育中前期为主,氮肥的分次施入应在块根增长初期完成。 相似文献
5.
对油葵群体光合作用及相关性状的初步研究结果表明 :油葵群体净光合日变化呈单峰曲线 ,峰值一般出现在 1 2 :0 0~ 1 3:0 0 ,净光合持续时间为 1 3h ,中上部叶层透光率较大 ,且对光合产物的贡献率达 85%,春播的群体光合高于复播 ,这与春播油葵的籽粒干物质积累速率、灌浆速率及产量分别比复播高出 2 9.7%、5.6%及 1 0 .6%是一致的 相似文献
6.
花铃期土壤含水量对棉花群体生理和产量影响研究 总被引:5,自引:0,他引:5
对两个不同生态类型的棉花高产品种,从开花前至盛铃期以前,模拟生产中常出现的四种棉田供水情况,研究表明:花铃期适水供应处理棉田,叶面积指数增长快、群体干物质积累速率高、产量高,主要原因在于棉花群体光合速率高,呼吸虽高,但呼吸所占比例较低所致。后旱处理对棉花的产量影响不明显,但可大大提高水分利用率。中后旱处理对棉花产量及水分利用效率影响最大;新陆早7号忍耐中后期干旱较弱于新陆早6号。 相似文献
7.
通径分析在冬小麦受渍胁迫诊断指标敏感性分析中的应用 总被引:1,自引:0,他引:1
根据冬小麦测坑试验结果,采用相关分析和通径分析的方法,计算了以叶片光合速率Pn、气孔导度Cond、蒸腾速率Tr、叶面温度T1、光合有效辐射PAR和地下水位累积水深SEW50 6种排水决策指标为自变量对作物阶段干物质产量的通径系数、相关系数、决定系数和对回归方程估测可靠程度R2的总贡献,建立了作物受渍胁迫诊断指标对干物质产量的回归方程.结果表明,影响干物质产量最大的是叶片光合速率,其次是地下水累计水深和叶片温度,决定系数分析结果与通径分析结果有一致的变化趋势.通过自变量指标的减少对结果的影响分析发现,在追求受渍胁迫下冬小麦干物质生产最优目标时,排水决策指标要注意叶片光合速率、地下水累计水深和叶片温度的变化. 相似文献
8.
通过摘叶处理研究了地膜甜菜不同源叶(组)对产量和含糖量的作用。结果表明:不同叶组对地膜甜菜块根膨大的贡献大小依次为:第11~15叶>第16~20叶>第21~25叶>第26~30叶>第31~35叶>第36~40叶。对块根糖分积累贡献顺序依次为:第31~35叶>第36~40叶>第26~30叶>第21~25叶>第16~20叶>第11~15叶。对单株甜菜产糖量的贡献大小依次为:第11~15叶>第31~35叶>第16~20叶>第21~25叶>第26~30叶>第36~40叶。前期叶片损失使青头比例显著增加,后期叶片损失青头重量和青头比例有所降低。光合测定的结果表明,摘叶后单株光合、水分利用效率显著下降,呼吸强度也有下降的趋势。群体光合测定的结果表明,摘除11~25片叶在叶丛繁茂期—块根膨大期净光合强度下降最多,摘除31~40叶后叶片在糖分积累期净光合强度下降最多,表明它们分别是叶丛繁茂期—块根膨大期和块根膨大期的主要功能叶。 相似文献
9.
为明确甜菜源库器官对叶丛期调亏灌溉的适应性响应特征,选取Beta356甜菜品种为试验材料,在叶丛期设置土壤水分下限分别为田间持水量70%(T1)、50%(T2)、30%(T3)的调亏灌溉处理,测定并分析各生育时期甜菜农艺性状的变化特征.结果 表明:叶丛期调亏灌溉条件下,该时期甜菜单叶光合速率、叶片数量、叶面积、块根体积... 相似文献
10.
不同播期对地膜甜菜产量及质量影响初探 总被引:2,自引:0,他引:2
甜菜是一种较耐寒的作物 ,苗期可耐低温 ,但温度过低 ,发芽时间长 ,温度过高则影响根系的生长。本试验就不同播期处理对甜菜生长状况 ,青头大小及甜菜块根品质的影响做了初步的研究。甜菜品种为新甜 7号。 4个播期处理分别为 3月 11日 (处理 1)、4月 7日 (处理 2 )、4月 14日 (处理3)、4月 2 1日 (处理 4 ) ,每处理相差 7天。每小区铺3膜 ,每膜为一处理 ,重复 3次 ,小区面积 3× 5m2 ,施肥、浇水与大田相同。试验结果见表 1~表 4。表 1 不同播期出苗所需时间、下胚轴长及产量、产糖量处理下胚轴长 /cm出苗天数根体长 /cm 产量 /kg.… 相似文献
11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness. 相似文献
12.
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly. 相似文献
13.
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well. 相似文献
14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation. 相似文献
15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。 相似文献
16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death. 相似文献
17.
Miao Maosheng 《华南师范大学学报(自然科学版)》2014,(6)
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula- 相似文献
18.
Yang Weitao 《华南师范大学学报(自然科学版)》2014,46(6):137-138
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re- 相似文献
19.
Bernard Kirtman 《华南师范大学学报(自然科学版)》2014,(6)
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that 相似文献
20.
《上海师范大学学报(自然科学版)》2014,(5):550
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with 相似文献