不同生育期干旱对冬小麦根冠生长发育的影响

用盆栽对冬小麦不同生育阶段进行不同程度水分调亏试验结果表明：拔节－孕穗期、抽穗－杨花期和灌浆－成熟3个阶段内土壤相对含水量（RW）上限为40％、50％、60％的水分亏缺均对作物的根冠发育产生了影响，拔节－孕穗期RW40％的水分亏缺处理使株高降低很多，低于不施肥的ck1，复水后也无法恢复。不同生育期的干旱均引起根冠干重的下降，根长则不同，水分亏缺有时会使根长增加，要看具体亏缺程度而定。根系不如冠部对干旱敏感，干旱促进营养物质向根的分配，减少了向冠部的运输，导致根冠比增大，另外，随生育期的推移，干旱对根冠比的影响减小。     

普通小麦体细胞无性系R2代变异发生特点

小麦Ｒ２代体细胞无性系变异存在４种发生方式，即合株性稳定谱异，全株分离变异，穗系嵌合稳定变异，穗系嵌合分离变异，其中稳定变异相当普遍、红占总变异的１／３。发生阶段较全株性变异于发生较迟的穗系嵌合变异。不同的变异性状有不同折发生方式。株型、穗型、芒型和叶色变异多为分离变异，熟期为稳定变异，株高，腊质等兼有稳定及分离变异，其中某性状是显性突变的结果，多数分离性状的分离均属简单分离，且箐少见到基因突变的     

优质晚籼稻恢复系R118的选育及应用

R118是湖南省永州市农科所用德国晚稻作母本，明恢63作父本进行人工杂交后定向选育而成的中熟晚籼恢复系，具有恢复力强，米质优，制种产量高等特点。R118所配系列组合表现产量高，稳定性好，米质较优，生育期适宜，适应性广，其中新香优118于2005年2月通过了湖南省农作物品种审定委员会审定。     

Spectrum and inheritance of resistance to the root-knot nematode Meloidogyne hapla in Rosa multiflora and R. indica

The spectrum and inheritance of resistance to the root‐knot nematode Meloidogyne hapla was studied in the diploid species Rosa multiflora and R. indica. The host suitability of seven rose rootstocks, namely five R. multiflora (K2, K1, Floradale, CE63 and CE65) and two R. indica (CE35 and Maroc) clonal accessions, was evaluated using four geographic isolates of M. hapla. Plants grown under greenhouse conditions were tested at high and durable inoculum pressure of nematodes and rated for nematode infestation five months after inoculation on a 0–5 gall index. Different host suitabilities to M. hapla were demonstrated depending on the nematode isolates: in R. multiflora, the clone K2 had a resistant (R) response to all isolates; the clone K1 ranged from intermediate (I) (isolate ‘Canada’) to resistant (other isolates), Floradale was shown to be intermediate, whereas CE63 and CE65 were moderate to good hosts (H). In R. indica, both rootstocks were good to excellent hosts for the isolate Canada but resistant to all three other isolates, thus expressing an isolate‐specific resistance. A study on the genetics of resistance in R. multiflora to the M. hapla isolate Canada was then conducted using an incomplete diallel cross involving all previous clones except Floradale. A total of 120 hybrid individuals belonging to several progenies representing the cross combinations R × I, R × H, I × H and H × H were evaluated. Individuals of each progeny generally ranged into a monomodal distribution that suggests polygenic inheritance of resistance. In the family Rosaceae, the differences in the resistance genetics to the meiotic species M. hapla and to the mitotic species, M. arenaria, M. incognita and M. javanica are discussed in relation to the reproductive status of the nematodes.     

夏播大豆品种的生育期特性与农艺性状的关系分析

从 339个大豆品种中选取生育期小于 1 0 0d的 1 0 3个品种进行生育期结构特性与农艺性状的分析。结果表明 :①R1最长的为华北品种 ,最短的为外国品种 ;②R7最长的为东北品种 ,最短的为南方品种 ;③R1与生育前期即营养生长阶段 ,高纬地区长于低纬地区 ;R7与生育后期即生殖生长阶段 ,低纬地区长于高纬地区 ;④R1、生育前期长的品种 ,单株荚数、单株粒数多 ,株高较高 ;R7、生育后期长的品种 ,百粒重高 ;⑤筛选出一批对光温不敏感的品种     

改进微波装置辅助提取猕猴桃根三萜类化合物的研究

应用单因素试验、析因试验和响应面分析法等统计学方法，对自行设计的可以同时控制温度的微波装置辅助提取美味猕猴桃根中具有保肝作用的三萜类化合物的工艺进行了深入研究。试验结果表明：在微波功率一定的情况下，乙醇浓度、提取温度和提取时间的影响最显著，优化得到最佳微波辅助提取工艺参数为乙醇浓度63%，温度47℃，时间为30 min，一次提取率可达85.13%。经验证试验证明，该方法是一种实用的提取方法。     

Chloride Ion Diffusion Coefficient Model of R.C. Elements under Multiple Factors

Based on the analysis of chloride ion-induced erosion mechanism of reinforced concrete and the Fick’s second law, a multi-factor model of the chloride ion erosion is established. In this model, the influences of water-cement ratio, humidity, time, temperature, and chloride ion binding capacity of concrete are taken into consideration, and the mathematic solution to the new model is provided by considering the boundary conditions. The new model is verified by analyzing the long-term exposed experiment data. Compared with the traditional model of Fick's second law, the model can indicate the development trend of the structure eroded by chloride and the chloride ion concentration in different depth, and at the same time, it can predicate the chlorine ion concentration on rebar surface in different corrosion periods and the initiation corrosion time of reinforcement.     

手掌参生药鉴定的研究

中药手掌参为兰科植物手参Gymnadenia conopsea R.Br.的干燥块根.本文对其外部形态及组织特征作了描述,附图2幅。此外,许多植物分类学及中药学典籍中有关手参地下部分的记载是错误的。他们认为是块茎,而我们认为它是块根。     

The Application of ISSR Markers to Identify the Fertility Restorer Gene Rf6 in T.timopheevii Cytoplasmic Male Sterile Wheat(Triticum aestivum)

Inter-simple sequence repeat (ISSR) analysis was carried out on a F2 population of 147 plants derived from a cross between a wheat male fertility restorer line 2114 and a male sterile line ND44A. Out of 43 primers examined, 18 primers produced distinguishable, polymorphic bands between the two parents. Linkage analysis in the mapping population showed that two markers UBC-808 and UBC-848 were closely linked with the restorer gene R f6 of the Triticum timopheevii CMS system. The distance between the two markers and the restorer gene was 7.9 cM and 4.9 cM, respectively. Also two parents were screened with 181 pairs of SSR primers, of which, 34.3% showed polymorphisms. But no locus was found linked with the restorer gene.Compared with the SSR technique, the ISSR approach used in the experiment provided more information and proved to be a valuable method to identify alien fragments.     

葡萄砧木99R再生体系的建立

以99R葡萄无菌苗叶片、叶柄和茎段为外植体诱导不定芽再生,在MS培养基中附加不同浓度的6-BA与IBA、TDZ与IBA、6-BA与2,4-D组合。结果表明,叶片和叶柄较适宜的再生培养基为MS 5.0 mg/LBA 0.1 mg/L IBA,再生率分别为40.54%和50.00%,茎段适宜培养基为MS 2.0 mg/L BA 0.02 mg/L IBA,再生率达62.50%;一定时间的暗培养处理利于99R葡萄不定芽再生,3周为最适暗培养时间;不同节位外植体不定芽再生率随叶片节位下降而降低;卡那霉素浓度>3.0 mg/L时显著抑制叶片不定芽的发生,头孢霉素浓度<300 mg/L对叶片再生不定芽影响很小。