不同玉米品种子粒脱水速率研究

以郑单958、先玉335、农华101、登海11、中单909、正大12为研究材料,研究了子粒、苞叶、穗轴含水量及其脱水速率。结果表明：不同品种间的子粒、苞叶、穗轴含水量差异极显著,不同品种间的子粒脱水速率差异极显著。子粒含水量与苞叶、穗轴含水量呈极显著正相关,相关系数分别为0.777和0.267,苞叶含水量与穗轴含水量呈极显著正相关,相关系数为0.312。先玉335、农华101在子粒脱水前期较其他品种脱水快且快速脱水时间长,收获时（9月24日）的子粒含水量分别为25.40%和26.58%;符合机械收粒的标准,可作为机械收粒的备选品种。     

乙醇脱水产物的气相色谱分析

利用色谱分离技术及碳平衡原理构建了准确可靠的乙醇脱水制乙烯的分析方法,并对HZSM-5分子筛催化剂的活性进行了评估.结果表明,在乙醇质量浓度为50％,质量空速为2.0/h,温度为280℃的反应条件下,催化剂的活性比较理想,乙醇的转化率和乙烯的选择性分别达到99.60％和98.10％.进一步升高反应温度,乙烯的选择性明显下降.     

单粒播种玉米品种收获期和后期脱水速率初探

2010年研究了5个单粒播种夏玉米品种的收获期和后期籽粒脱水速率。研究结果表明:当籽粒黑色层形成、果穗苞叶彻底松散时,可作为夏玉米最佳收获期的标准。5个品种的平均日增产量为98.58～244.49 kg/hm2。在参试的5个品种中,以先玉335收获时的籽粒含水量最低,为19.85%;以登海662的后期籽粒平均脱水速率最大,达0.738%/d。     

植物低温诱导蛋白的研究进展

低温能够诱导植物基因的表达从而合成新的蛋白质,这些蛋白质具有增强细胞抗冰冻脱水能力、保护酶行使正常功能和代谢调节功能及稳定细胞膜等作用。植物低温诱导蛋白及其理化性质与抗冻关系一直是国内外的研究热点。综述了抗冻蛋白、脱水蛋白和热激蛋白3种低温诱导蛋白的最新研究进展及与植物抗冻性的关系。     

脱落酸预处理对蝴蝶兰类原球茎及其脱水耐性的效应

[目的]了解脱落酸(ABA)溶液预处理对蝴蝶兰类原球茎(PLB)的影响及对其耐脱水性的效应。[方法]观测H2O浸泡PLB对其耐脱水性的效应,H2O、ABA溶液预处理对PLB的影响,以及ABA溶液预处理PLB的耐脱水性。[结果]浸水PLB的含水率和成活率较新鲜PLB明显提高。H2O或ABA溶液浸泡1 h后的PLB重量(浸泡重)差异不显著,H2O或ABA溶液浸泡不能明显改变PLB干物质重量、相对电导率和成活率。较H2O浸泡,80μmol/L ABA溶液预处理使PLB脱水处理后的脱水重/鲜重提高24.8%,成活率提高51.5%。[结论]ABA溶液短时间预处理蝴蝶兰PLB并不能改变其重量和造成损伤。ABA预处理能稍提高脱水处理后PLB含水率,可能只是脱水耐性提高的原因之一。     

玉米杂交种生理成熟后子粒田间自然脱水速率差异分析

以黑龙江省推广的12个玉米杂交种为试验材料,研究了玉米杂交种生理成熟后子粒田间自然脱水速率差异。结果表明,供试玉米杂交种生理成熟期在抽丝后55d至65d,品种间田间自然脱水速率差异极显著;适合第一积温带南部的6个杂交种中吉单180的田间自然脱水速率最快,达到0.840%/d,其次是本育9,达到0.815%/d,最低是丰禾10,为0.305%/d;适合第一积温带西部的3个杂交种中庆单2脱水最快,达到0.795%/d,其次为四单19和金玉1号;适合第二积温带中西部的3个杂交种中白单9最高,达到0.875%/d,其次为东农250,达到0.525%/d。其结果为快速脱水玉米杂交种选用提供参考依据。     

Plant traits and functional types to characterise drought survival of pluri-specific perennial herbaceous swards in Mediterranean areas

Perennial grasslands provide numerous environmental benefits but their response to severe drought and therefore their sustainability in arid and Mediterranean areas have been little studied. Due to climate change, models of pasture production should be able to predict sward evolutions under increasing aridity. Our general goal was to identify plant traits and functional types that could be included in models aiming to analyse the dynamics of contrasting types of herbaceous plants grown in mixtures under drought. The two steps were: (1) to investigate the morpho-physiological traits associated with drought survival within a mixture of perennial herbaceous populations and to test whether the physiological traits measured under optimum conditions of growth in Spring may predict plant responses under subsequent summer drought and (2) to identify functional groups of populations exhibiting similar responses to the disturbance regime caused by severe drought. Seven different populations from five species were grown in monocultures (pots, long columns) and mixtures (containers, field). Standard leaf functional traits, aerial and root biomass were assessed under non-limiting water supply in Spring. In Summer, under continuous severe drought, leaf water status and plant survival were measured.Senescence of aerial tissues at the end of Spring, associated with endogenous summer dormancy, water status maintenance in basal tissues during the intense drought, and root biomass in the field were the variables best correlated with drought survival. The standard leaf functional traits specific leaf area (SLA) and leaf dry matter content (LDMC) measured in Spring under full irrigation, were uncorrelated with drought survival. These results suggested no general trade-off between growth potential and drought survival. Under conditions of optimal production in Spring, correlations were established between functional traits and variables associated with aerial biomass productivity which discriminated the group of forage cultivars from the other genotypes. Under summer drought, four main functional types of genotypes were defined according to their strategy of water use and therefore contrasting survival and persistence. This typology will be used to base further modelling study aiming to assess the effects of increasing aridity on the stability and productivity of herbaceous swards on the long term.     

回干处理对2种野生禾草种子萌发的影响

[目的]探索不同牧草种子在干旱条件下的萌发能力,为恢复草地植被和补播生产实践提供理论依据。[方法]以野生羊草和无芒雀麦的种子为材料,设置回干时间(1、10、20 d)和回干温度(20、30℃),进行回干处理,用15/25℃变温条件下纸上萌发法测定种子的萌发率及发芽指数。[结果]羊草和无芒雀麦吸水-回干处理后种子萌发率均下降,羊草下降幅度为5%~13%,无芒雀麦下降幅度为5%~10%。回干时间和回干温度对羊草和无芒雀麦的发芽率和发芽指数都有影响,羊草种子能耐长时间的低温回干(20℃,20 d),无芒雀麦种子能耐短时间的高温回干(30℃,1~10 d)。[结论]不同的牧草品种耐回干的能力不同。