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231.
TDZ诱导的黄芩 (Scatellaria baicalensis Georgi)外植体枝再生研究(英文) 总被引:2,自引:0,他引:2
研究了中药黄芩 (ScatellariabaicalensisGeorgi)的微繁技术。TDZ[N phenyl-N’ (1,2 ,3 thidiazol 5 ylurea) ]用于组培中能有效地诱导黄芩完整实生苗、白化下胚轴段和茎段再生新枝。下胚轴段和茎段外植体的组织学研究显示其再生是通过愈伤组织形成新枝。TDZ诱导黄芩 3种组培外植体枝再生的比较表明 ,理想的再生不一定要外植体脱离母体。黄芩完整实生苗的下胚轴上形成的枝明显多于下胚轴段上形成的枝 ,表明完整实生苗中产生的代谢产物提供枝再生所需的物质。 95 %以上的再生体形成根系 ,在无菌培养和温室中可形成完整植株。本研究所采用的再生程序可以用于这种药用植物的改良和大量繁殖 相似文献
232.
A.M Manschadi J Sauerborn H Stützel W Göbel M.C Saxena 《European Journal of Agronomy》1998,9(4):259-272
Root growth of faba bean genotype ILB 1814 grown under both limited and sufficient moisture supply was studied in 1993–1994 and 1994–1995 at ICARDA's Tel Hadya research station. Crops were sown on two dates in both growing seasons. Root-length density (RLD) and root dry weight were measured at four depths in three locations relative to the crop row. In general, RLD decreased considerably with depth, and by the start of pod-filling, around 60% of the roots were found in the top 15 cm of soil. In the upper 30 cm soil profile, the RLDs of drought-stressed faba beans were significantly lower than those measured beneath well-watered crops. In the deeper soil layers, the RLDs were similar in both moisture supply treatments. An existing root model was employed for the simulation of faba bean root growth. The model estimates the depth of rooting and RLD in each soil layer based on dry matter allocation to the root system, soil layer water contents, genotype-specific rooting characteristics, and soil physical properties. A faba bean growth model provided daily allocation of dry matter to roots as well as soil layer water contents. Overall, with a few modifications, the root model was capable of predicting the RLD of faba bean grown both under limited and sufficient water supply realistically. Limitations of the model and some aspects that need further improvement are discussed. 相似文献
233.
A.M. Manschadi J. Sauerborn H. Stützel W. Göbel M.C. Saxena 《European Journal of Agronomy》1998,9(4):273-293
This study reports the adaptation of a simple and mechanistic crop growth model for faba bean (FAGS) to growing conditions in the Mediterranean region. The FAGS model was originally developed for small-seeded cultivars grown in the temperate zone under non-limiting water and nutrient conditions. In order to account for the effect of drought stress on faba bean growth, a submodel for the simulation of soil water balance has been included in the FAGS model. The enhanced FAGS model was calibrated using data from field experiments with a large-seeded faba bean genotype (ILB 1814) conducted in 1993–1994 and 1994–1995 at ICARDA's Tel Hadya research station in northern Syria. In both seasons, crops were sown on two dates under different water supply levels. The model was capable of predicting the faba bean phenology, leaf area development, biomass production, and grain yield as well as the soil water extraction using daily climatic data, genotype-specific parameters, and soil physical properties. The calibrated faba bean model was tested against independent experimental data from the 1991–1992 and 1992–1993 growing seasons at Tel Hadya and was able to satisfactorily predict grain yield of crops grown under different drought intensities. Limitations of the model and aspects requiring better understanding to improve model predictions are discussed. 相似文献