Comparison and early selection of new clones in <Emphasis Type="Italic">Populus tomentosa</Emphasis>

In our study, two experimental plantations, respectively, with 24 and 32 new clones of P tomentosa, were established in Weixian County, Hebei Province and Wuzhi County, Henan Province using a completely randomized block design. A comparative study was conducted on the continuous 5-year-old height and diameter at breast height （DBH） of new clones in the two plantations. As well, based on genetic correlation over the years of testing of these clones, a preliminary study of early selection was carried out. Results indicate that the growth traits of the new clones in Weixian were better than those in Wuzhi. The traits show weak correlation between the two plantations. In some stands, the height, DBH and seedling volume of 5-year-old clones presented statistically significant differences among clones. In both plantations, the new clones showed over 0.6 repeatability of height, DBH and volume, as well as larger coefficients of variation （CV）. The fact that these clones achieved the largest repeatability and CV in the second year suggests that these traits are highly controlled by heredity. Thus, based on the growth traits of the second year, the new clones B305, B307, B303, H75, BT18, BT17 and 21J-1 were considered suitable in Weixian. In Wuzhi, the new clones had variable repeatability and CVs in various years and their correlation of growth traits among different years was not high. We conclude that early selection of new clones was not feasible in Wuzhi.     

利用反硝化技术净化养殖水体的研究进展

随着水产养殖业的大力发展,养殖水体净化技术的研究受到普遍重视,利用反硝化技术净化养殖水体的研究日益增多。本文中阐述了养殖水体中硝酸盐积累所造成的危害,详细介绍了养殖水体反硝化净化机理以及生物载体、碳源选择、脱氧方法和反硝化工艺等的研究进展,并对反硝化技术在养殖水体净化方面的应用前景进行了探讨分析。     

利用ITS序列探讨谷精草属5个种的系统发育

以谷精草属(Eriocaulon)的尼泊尔谷精草（Eriocaulon nepalense）、白药谷精草（E. cinereum）、高山谷精草（E. alperstre）、华南谷精草（E. sexangulare）、南亚谷精草（E. oryzetorum）等5个种为研究对象，通过PCR扩增技术获得了谷精草属5个种的内转录间隔区序列，并对ITS序列进行分析. 结果发现，供试谷精草属植物的ITS区长度并不完全一致，其ITS1的长度范围为171～306 bp，G+C含量为38.24%～55.04%；ITS2的长度范围为184～288 bp，G+C含量为 36.46%～57.02%. 在此基础上，采用Clustal W version 1.7对所得的ITS序列进行排序与分析，以灯心草属（Juncus）的一个种J. dregeanus为外类群，并使用PAUP 4.0 10 b软件采用最大简约法分析获得最简约的系统发育树. 结果表明，在检测的ITS序列的738个位点中稳定位点174个、变异位点564个 (包括276个信息位点). 另外，从发育树上平行分出两个大的总分支，其中E. nepalense、E. oryzetorum、E. alpestre和E. cinereum（云南宣威）为一支；E. sexangulare为一支. 上述二个分支与外类群聚在一起，bootstrap值为100％.      

Construction and Characterization of cDNA Library from Water-Stressed Plantlets Regenerated in vitro of Populus hopeiensis

In order to isolate and clone water-stress-responsive genes, total RNA was extracted from water-stressed plantlets regenerated in vitro of Populus hopeiensis using a QIAGEN RNeasy Plant Mini Kit. CDNA, synthesized by LD-PCR with the SMART cDNA Library Construction Kit, was n vitro packaged into a phage λTriplEx2 vector. The resulting primary library and amplified library have a titer of 1.68×10i6 and 1.69×109 pfu·mL–1 respectively. The combination ratio reached 98.8% and the average size of inserts was about 800 bp. In addition, the percentage of inserted fragments (> 400 bp) was approximately 90%. The results indicate that a cDNA library has been successfully constructed.     

Comparison and early selection of new clones in Populus tomentosa

In our study, two experimental plantations, respectively, with 24 and 32 new clones of P. tomentosa, were established in Weixian County, Hebei Province and Wuzhi County, Henan Province using a completely randomized block design. A comparative study was conducted on the continuous 5-year-old height and diameter at breast height (DBH) of new clones in the two plantations. As well, based on genetic correlation over the years of testing of these clones, a preliminary study of early selection was carried out. Results indicate that the growth traits of the new clones in Weixian were better than those in Wuzhi The traits show weak correlation between the two plantations. In some stands, the height, DBH and seedling volume of 5-year-old clones presented statistically sig-nificant differences among clones. In both plantations, the new clones showed over 0.6 repeatability of beight, DBH and volume, as well as larger coefficients of variation (CV). The fact that these clones achieved the largest repeatability and CV in the second year suggests that these traits are highly controlled by heredity. Thus, based on the growth traits of the second year, the new clones B305, B307, B303, H75, BT18, BTI7 and 21J-1 were considered suitable in Weixian. hi Wuzhi, the new clones had variable repeatability and CVs in various years and their correlation of growth traits among different years was not high. We conclude that early selection of new clones was not feasible in Wuzhi.     

考力代羊生长性状的协方差函数估计

试验旨在模拟考力代羊生长过程中的遗传和表型变异,为其选种提供一定的依据.用1 269只考力代羊的3 332个生长发育记录,配合自变量为年龄的勒让德多项式的随机回归模型(RRM),其中个体加性遗传效应配合5阶,母体永久环境效应配合2~5阶,对数约束最大似然值和信息标准用来检测最佳配合阶数.用平均信息约束最大似然(AIREML)法来估计体重的遗传、环境和表型协方差函数,结果表明,母体永久环境效应配合4阶时,协方差图更符合考力代羊的生长变化情况,涉及的参数也较少,且羔羊在6月龄前后表现出较大的遗传和表型变异.这些结果提示随机回归模型在有限的数据下能够充分描述考力代羊体重在连续时间轴上的增长变化情况.     

红掌切花的瓶插保鲜液研究

[目的]研究红掌切花的瓶插保鲜液,为红掌种植及筛选保鲜方法提供参考.[方法]以红掌(Anthurium seherzerianum)中的常用切花品种'热情'为试验材料,采用3种不同的瓶插液配方,处理①:2%二甲基琥珀酰肼+1%8-羟基喹啉硫酸盐(HQS)+0.1%Ca(NO3)2+5%蔗糖;处理②:5%蔗糖+0.1 g/L明矾+10 mg/L 6-BA;处理③:4%蔗糖+ 0.08% NaCl+0.01%过磷酸钙+0.01%中药杀菌剂(黄连的乙醇提取液)+0 1 mmol/L NaOH+0 1 mmol/L柠檬酸+10 mg/L 6-BA.并与常用红掌保鲜配方(4%蔗糖+50 mg/L AgNO3+0.05 g/L NaPO4)进行对比,筛选最佳的红掌瓶插保鲜液.[结果]试验中处理①的配方比较简单,不能很好地杀菌,处理②虽然含有一定的碳源和营养,也有杀菌剂,但组成较简单,仍不能很好地满足红掌切花采后各方面生理的需要,以配方③为最佳的瓶插保鲜液,保鲜期为23 d,比对照延长了13 d,观赏期达31 d,比对照延长了18 d,效果显著;且配方③明显地减少了红掌佛焰苞的水分丧失,有利于维持组织的含水量,降低细胞膜透性,抑制膜脂的过氧化作用,减少丙二醛含量的积累,提高了SOD的活性,提高了细胞保护酶的活性,增加了脯氨酸和可溶性糖的含量,降低了呼吸速率.[结论]4%蔗糖+ 0.08% NaCl+0 01%过磷酸钙+0.01%中药杀菌剂(黄连的乙醇提取液)+0.1 mmol/L NaOH+0.1 mmol/L柠檬酸+ 10 mg/L 6-BA配方达到了延长红掌佛焰苞保鲜期的目的.     

红掌切花的瓶插保鲜液研究（摘要）（英文）

[目的]研究红掌切花的瓶插保鲜液,为红掌种植及筛选保鲜方法提供参考。[方法]以红掌（Anthurium seherzerianum）中的常用切花品种‘热情’为试验材料,采用3种不同的瓶插液配方,处理①：2%二甲基琥珀酰肼＋1%8-羟基喹啉硫酸盐（HQS） ＋0.1%Ca（NO3）2＋5%蔗糖;处理②：5%蔗糖＋0.1 g/L明矾＋10 mg/L6-BA;处理③：4%蔗糖＋0.08% NaCl＋0.01%过磷酸钙＋0.01%中药杀菌剂（黄连的乙醇提取液） ＋0.1 mmol/LNaOH＋0.1 mmol/L柠檬酸＋10 mg/L6-BA。并与常用红掌保鲜配方（4%蔗糖＋50 mg/LAgNO3＋0.05 g/LNaPO4）进行对比,筛选最佳的红掌瓶插保鲜液。[结果]试验中处理①的配方比较简单,不能很好地杀菌,处理②虽然含有一定的碳源和营养,也有杀菌剂,但组成较简单,仍不能很好地满足红掌切花采后各方面生理的需要,以配方③为最佳的瓶插保鲜液,保鲜期为23 d,比对照延长了13 d,观赏期达31 d,比对照延长了18 d,效果显著;且配方③明显地减少了红掌佛焰苞的水分丧失,有利于维持组织的含水量,降低细胞膜透性,抑制膜脂的过氧化作用,减少丙二醛含量的积累,提高了SOD的活性,提高了细胞保护酶的活性,增加了脯氨酸和可溶性糖的含量,降低了呼吸速率。[结论]4%蔗糖＋0.08% NaCl ＋0.01%过磷酸钙＋0.01%中药杀菌剂（黄连的乙醇提取液） ＋0.1 mmol/L NaOH＋0.1 mmol/L柠檬酸＋10mg/L6-BA配方达到了延长红掌佛焰苞保鲜期的目的。     

4YK-K型床作苗木移植机设计及主要电气元件的选择

4YK—K型床作苗木移植机是一种新型苗木移植换床设备，其采用机、电、气一体化控制系统。介绍了该机的主要零部件设计及电气元件的选择。     

和谐的立体·生态农业生产与贫困山区的脱贫致富

阐述了立体、生态农业的基本内涵,介绍了立体、生态农业的基本模式(理论模式、实践模式)和架构,在依靠立体、生态农业致富的基础上,提出了贫困山区发展和谐的立体、生态农业的建议。