不同刈割时间收获后的羊草、芦苇水分和呼吸的变化

以多年生草本植物羊草和芦苇为实验材料,研究1d中不同时间（9∶00、13∶00、17∶00）刈割后含水量、气孔导度及呼吸速率的变化。结果表明：（1）羊草、芦苇刈割后水分散失均经历三个阶段：快速失水1d,缓慢失水2～3d,平稳期1d。芦苇叶片呼吸速率下降快,刈割5h后呼吸微弱,接近死亡;羊草叶片呼吸速率下降慢于芦苇,刈割7h后仍存在生理活动;（2）依据水分散失和呼吸代谢指标,三个刈割时间中,9∶00刈割能最大程度地减少干草调制过程中的养分损失,有益于制作优质干草。     

15份马蔺材料苗期抗旱性比较

采用温室模拟旱境胁迫-复水方法,对采自我国北方不同生境条件下的15份野生马蔺(Iris lactea Pall.var.chinensis(Fisch.))种质材料苗期的形态学和生理生化指标进行测定与分析,综合比较其抗旱性能。结果显示:随干旱胁迫时间延长,其叶片相对含水量、叶绿素含量、植株相对生长率均呈下降趋势,相对电导率、丙二醛含量与游离脯氨酸的含量则有增加趋势,复水后均有不同程度恢复。采用欧氏距离法进行数学聚类分析,可将15份马蔺种质材料的抗旱性划分为3个抗旱级别,即相对抗旱包括ML008、ML007、ML015、ML009和ML006;中度抗旱包括ML014、ML012、ML011、ML013、ML010、ML005、ML004和ML003;相对旱敏感包括ML002和ML001。各种质材料抗旱生理指标间显著相关(P<0.05)。     

电动助力转向系统直流伺服技术的研究

针对电动转向系统原有单一控制方式的不足，根据直流脉宽调制伺服系统工作原理，提出了一种带有助力和阻尼两种模式的综合控制方式。通过对两种模式分别进行分析计算，提出了一种针对占空比和控制模式的修正方法。台架性能试验验证表明，采用这种伺服控制方式，电动助力转向系统快速回正时的平稳性有所提高。     

红金银花组织培养试验研究

以红金银花的顶芽为外植体,采用正交试验设计,对红金银花顶芽的初代培养、继代培养、生根培养进行了研究.结果表明:初代培养的最适培养基为:MS+6-BA(1.0 mg/L)+NAA(0.1～0.2 mg/L),最适蔗糖浓度为20.0 g/L;继代培养的最适培养基为MS+6-BA(1.5 mg/L)+NAA(0.2 mg/L)+GA3(0.5 mg/L);生根培养以1/2MS+6-BA 0.25 mg/L+NAA 1.0 mg/L+活性炭1.0 g/L,即可得到理想的生根苗.     

田间施用硝化抑制剂DMPP对小青菜贮藏过程中硝酸盐与Vc含量的影响

采用田间施药方法,研究了施用硝化抑制剂3,4-二甲基吡唑磷酸盐(3,4-dimethylpyrazolephosphate,DMPP)对冰箱贮藏条件下小青菜可食部分硝酸盐、维生素C(Vc)含量变化的影响。结果表明,在贮藏过程中,施与不施DMPP2种处理小青菜硝酸盐含量呈现先降低后略有升高的趋势,Vc含量呈降低的趋势;DMPP在贮藏前期能够有效地降低硝酸盐含量,延缓Vc含量的降低。贮藏2d后,DMPP处理小青菜硝酸盐、Vc含量分别降低了74.4和9mg·kg-1,而对照处理分别降低了54.4和50mg·kg-1,处理间硝酸盐、Vc降幅差异均达5%显著水平。贮藏2～4d中,DMPP处理硝酸盐、Vc含量分别降低了20.1和91mg·kg-1,而对照处理分别降低了144.7和84mg·kg-1,处理间硝酸盐含量降幅差异达5%显著水平。贮藏4～6d中,对照处理硝酸盐含量升高了60.6mg·kg-1,DMPP处理升高了76.2mg·kg-1,Vc含量分别降低23和117mg·kg-1,且处理间降幅差异达5%显著水平。蔬菜贮藏时间不要过长,以不超过4d为宜。     

Effect of the Antisense BcMF12 Driven by the BcA9 Promoter on Gene Silencing in Brassica campestris L. ssp. chinensis

The study analyzed the silencing of BcMF12 gene regulated by BcA9 promoter in the transgenic pakchoi and confirmed the effect of antisense BcMF12 gene on the pollen development. A conserved BcMF12 gene fragment was amplified from the cDNA of flower buds in pakchoi (Brassica campestris L. ssp. chinensis, syn. B. rapa L. ssp. chinensis) and was fused to the anther specific BcA9 promoter. The plant antisense expression vector was constructed and then introduced into pakchoi via Agrobacterium-mediated transformation. The transgenic plants were screened by antibiotics and molecular analysis. PCR and Southern blot revealed that the antisense BcMF12-GUS fusion gene regulated by BcA9 promoter was integrated into transgenic plants. Northern blot suggested that the expression of BcMF12 gene was down-regulated significantly. The pollen germination rate of transgenic plants with antisense BcMF12 gene decreased as compared with that of the control plants. The expression of the gene BcMF12 related to the pollen development was inhibited by the antisense BcMF12 driven by BcA9 promoter, which consequently affected the pollen development in pakchoi.     

Characteristics of nucleotides and amino acids in cDNA sequence of xyloglucan endotransglycosylase cloned from <Emphasis Type="Italic">Anthocephalus chinensis</Emphasis>

Xyloglucan endotransglycosylase is an identified relaxation factor with functions of easing and extending of plant cell walls.Its activities are directly related to plant growth and elongation of organisms.Anthocephalus chinensis is a tall and fast growing evergreen tree species.We cloned the full cDNA sequence of AcEXT genes which is abundantly expressed in the cambium of A.chinensis.The sequence analysis of nucleotides and amino acids revealed the presence of a 1396 bp full cDNA sequence,including a 960 bp complete open reading frame(ORF) encoding a 320 amino acid protein.The deduced amino acid sequence of AcXET was homologous to the other known XET proteins and contained the conserved EIDFE catalytic site which was specific to all the XETs.Our data should serve as a foundation for further insight into AcXET gene molecular mechanisms during wood formation and cell wall engineering of woody plants.     

五味子冰激凌制作工艺及配方

选择红色的五味子果实作为冰激凌的主要原料,以草莓、枸杞、玫瑰、玫瑰茄为辅料,进行冰激凌制作试验,结果表明:复合果浆的最佳配方为五味子汁20.0%、枸杞果浆10.0%、草莓果浆30.0%、玫瑰汁4.0%;冰激凌的最佳配方为复合果浆40.0%、乳粉8.0%、乳化稳定剂0.6%、奶油10.0%、甜味剂(蛋白糖)0.2%、玫瑰茄40.0%、柠檬酸0.1%、色素适量。     

北五味子主要性状的遗传参数及相关性研究

对辽宁省本溪县北五味子示范园内三年生成熟期北五味子主要性状的遗传参数及性状间遗传相关性分析,并在遗传相关的基础上对产量性状进行逐步回归和通径分析。遗传参数分析结果表明：果穗数、平均穗重、产量、地茎、穗粒数的变异系数较大,育种选择潜力大。遗传相关分析结果表明：产量及果穗数分别与地茎呈极显著、显著正相关,与比叶重间呈极显著负相关。逐步回归分析表明：对产量贡献较大的性状主要有果穗数、平均穗重、果穗长和比叶重,其中比叶重对产量为负向效应。通径分析结果表明：与产量主要相关的5个性状中果穗数对产量的直接正向效应值最大,总间接正向效应值最小;果穗数对产量的直接效应为正,总间接效应为负,且直接效应绝对值大于总间接效应;果穗长与地茎对产量的直接与间接效应均为正向,且总间接效应大于直接效应;比叶重对产量的直接效应与间接效应值均为负,直接效应与间接效应数值相差不大。