水稻需水量对旱涝交替胁迫的响应效应

通过农田水位调控以降低旱涝胁迫对水稻生长影响的研究已成为稻作节水学科研究领域的热点问题.本文基于水位调控技术研究了旱涝交替胁迫下水稻生理胁迫程度和需水量的变化.结果表明:拔节孕穗期、抽穗开花期水稻抗旱涝胁迫能力较强,分蘖期和乳熟期较弱;水稻在两个生育期内受到旱涝交替胁迫时,水稻前期胁迫将对后期生长有影响且因后者对应水位不同而存在差异,其中拔节孕穗期和抽穗开花期连续进行旱涝交替胁迫处理使水稻生理生长机能遭到破坏,对旱涝胁迫的抵抗能力下降;旱涝交替胁迫下水稻全生育期需水量变化按照拔节孕穗期抽穗开花期乳熟期分蘖期依次降低,此外,除乳熟期处理对旱涝胁迫调控表现为不显著,其余生育期旱涝胁迫对需水量变化影响均显著.     

水稻不同生育阶段稻田水位调控对产量因子及产量的影响

以稻田水位作为调控指标,对水稻分蘖期、拔节孕穗期、抽穗开花期和乳熟期进行受旱试验,根据试验资料分析水稻不同生育期受旱对产量及其构成因子的影响。研究表明：水稻分蘖期受旱,对有效穗数最为不利,反而复水后会使穗粒数、结实率有所增加,对千粒质量影响不大,如分蘖期严重受旱,将导致严重减产;拔节孕穗期对水分很敏感,受旱对穗粒数和结实率均产生不利影响,会严重降低产量,而对千粒质量影响并不显著;抽穗开花期受旱对穗粒数、结实率和千粒质量均产生不利影响;乳熟期受旱主要对千粒质量产生不利影响。通过灰色关联度分析,得出水稻产量构成因子对产量贡献最大的为有效穗数。     

水稻孕穗期土壤干燥引起的不育

水稻孕穗期干旱对籽粒产量影响最大，因为干旱对籽粒产量影响最大，因为干旱使不育性急剧增加。我们的目的是确定干旱期间所引起的不育性的生理过程。试验品种３个：一个水稻品种、２个旱稻品种。采用盆栽，设置几种土壤处理，在孕穗期处理１０天，随着土壤干旱程度的增加，３个样品剑叶伸长率（ＬＥＲ）、干物质生产量（ＤＭＰ）和叶片水势（ＬＷＰ）都降低，而不育度增加。３个品种不育性的增加与ＤＭＰ的降低密切相关。过去认为是     

POD活性与水稻抗旱性的关系

以５种抗旱性不同的水、旱稻品种在水分胁迫条件下全生长期的叶为实验材料，采用愈创木酚法ＰＯＤ活性，探讨不同水稻品种生长期对水分胁迫的反应及其与抗旱性的关系。结果表明，受到水分胁迫的水、旱稻ＰＯＤ活性的高于对照；孕穗期和抽穗期是水分敏感期，在此期间，ＰＯＤ活性上升的幅度高于其它生长期。拔节期和成熟期是水旱稻全生长期中的ＰＯＤ活性较低的时期。     

水稻品种以及施肥措施对稻田甲烷排放的影响

１９９４年４月至１０月，在北京稻田试验田研究了不同水稻品种对甲烷排放的影响以及施肥措施对降低甲烷排放和提高水稻产量的匹配关系。实验表明稻田甲烷排放在品种之间存在着明显差异，实验中品种间甲烷排放通量最大差异可达到五倍。以有机肥混合硫酸铵作底肥并配合不同时间和不同用量的硫酸铵作追肥与仅施混合底肥不施施硫酸铵作追肥的相比较可减少甲烷排放约５８％，水稻产量提高３１．７％。可明显地抑制水稻生长期的甲烷排放高     

氮肥处理对水稻群体小气候及其产量的影响

为研究不同氮肥处理对水稻群体生态的影响,以杂交水稻F优498为材料研究不同氮肥施用水平下群体小气候、产量及纹枯病发病情况的差异.结果表明,随着氮肥施用量的增加杂交水稻的产量增加,但在高氮条件下产量增加不显著;增施氮肥后虽然结实率和千粒重下降,但是有效穗数显著增加(30%左右)导致了单株产量(19%左右)的提高.同时氮肥增加后其群体通透性(包括透光性和透气性)显著降低,温度降低但湿度增加;这一系列群体小气候的恶化导致纹枯病发病程度增加.氮肥过低无法保证产量,过高则会引起群体生态环境恶化.在中等施氮水平下(150 kg/hm~2),水稻的产量既不会显著降低,群体小气候条件也优于高氮处理.进一步研究不同肥料处理对群体小气候和产量的影响,可以探索出既能达到高产又可以降低病虫害发生的最优措施.     

水稻倒伏的原因及控制措施

水稻倒伏不仅影响水稻产量，同时还影响稻米的品质，生产中水稻倒伏以后一般减产15-20％，灌浆前倒伏可减产30％以上。     

POD活性与水稻抗旱性的关系

以５种抗旱性不同的水、旱稻品种在水分胁迫条件下全生长期的叶为实验材料，采用愈创木酚法测定ＰＯＤ活性，探讨不同水稻品种生长期对水分胁迫的反应及其与抗旱性的关系．结果表明，受到水分胁迫的水、旱稻ＰＯＤ活性均高于对照；孕穗期和抽穗期是水分敏感期，在此期间，ＰＯＤ活性上升的幅度高于其它生长期；拔节期和成熟期是水早稻全生长期中ＰＯＤ活性较低的时期．可以认为，在水分胁迫时，ＰＯＤ活性变化与在大田种植的水、旱稻抗旱性有一定的相关性．通过测定水分胁迫条件下敏感期ＰＯＤ活性变化幅度，可作为某一品种抗旱能力的生物化学指标．     

不同基因型水稻对低温潜沼性逆境的耐受能力及其农艺表现

低温潜沼性逆境是我国稻区常见逆境之一,研究不同基因型水稻对低温潜沼性逆境的耐受能力及农艺表现,对于提高稻田产量具有重要的理论意义和实践意义.研究选取四川盆地常用水稻品种,采用田间试验的方法,观测并分析不同水稻品种的分蘖动态、穗部性状等农艺指标.结果表明:① 低温潜沼性逆境下,耐受能力较强的协优027和冈优188,在分蘖期（5月306月30日）具有较强的分蘖能力,其最大分蘖数分别为24.93和23.90,显著高于其它参试品种;其平均株高增长率在分蘖期分别为5.2%和5.7%,显著低于其它参试水稻品种.② 协优027和冈优188在低温潜沼性逆境下的结实率较非逆境下的结实率分别降低5%和2%,穗长分别降低0.8%和0.1%,降低程度显著低于其它参试品种.③ 协优027和冈优188在低温潜沼性逆境下的稻谷产量分别为7.16,6.61 t/hm 2,显著高于辐优151（4.81 t/hm2）和川谷优204（3.43 t/hm2）.④ 低温潜沼性逆境下,水稻耐潜指数与水稻产量间的相关系数为0.64（P0.05）,与水稻产量降低程度间的相关系数为-0.78（P0.01）.低温潜沼性逆境耐受能力较强的水稻品种（协优027和冈优188）,在低温潜沼性逆境下的分蘖数较多,结实率和穗长降低程度较低,产量降低程度较小,更容易获得高产.水稻耐潜指数可以用来评价不同基因型水稻对低温潜沼性逆境的耐受能力,耐潜指数越高,其在低温潜沼性逆境下产量降低程度越小.     

冀东滨海稻区稻曲病侵染规律研究Ⅱ侵染时期

稻曲病是当前造成稻谷产量损失和降低稻米经济价值最主要的病害之一。国内外对稻曲病侵染规律研究有较多的报道。在侵染时期方面,大都认为在水稻孕穗期:I. Kegarmi(1960)在孕穗期采用向叶鞘内注射厚垣孢子悬浮液的方法接种成功;R. A. Singh(1985)认为菌核在六七月份的雨季萌发,子囊孢子成熟后与早播水稻扬花期一致,子囊孢子落到花器上侵染。广东黎毓千(1986)报道孕穗后期为此病的侵染时期。江苏黄正兴(1984)认为病菌的侵染时期在水稻破口至齐穗阶段。本研究自1987—1989年连续三年人工接种,对冀东滨海稻区稻曲的侵染时期进行试验,现将研究结果简报如下:     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

Features of Women's language

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

Quality traits in wheat （Triticum aestirum L.） were studied by quantitative trait locus （QTL） analysis in a recombinant inbred line （RIL） population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross （ChSh）. Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.