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171.
172.
[目的]研究不同激素对普陀水仙生理生化指标的影响。[方法]以普陀水仙为材料,在以清水为对照的基础上,分别研究6-BA和2,4-D 2种激素胁迫对其茎、叶生理生化指标的影响。[结果]在一定范围内,随着6-BA和2,4-D浓度的增大,普陀水仙叶中的SOD活性逐渐增大,POD活性逐渐减小,而茎中的SOD活性逐渐减小,POD活性逐渐增大;随6-BA和2,4-D浓度的增大,茎、叶中可溶性蛋白含量和MDA含量的变化则呈波动曲线变化;茎、叶中脯氨酸含量随激素浓度的增加先增高后降低,当激素浓度为3 mg/L时达最大值;在6-BA和2,4-D的胁迫下,普陀水仙叶片电导率均呈增高趋势,茎电导率在6-BA胁迫下随激素浓度的增大而增大,在2,4-D胁迫下随激素浓度的增大而减小。[结论]根据试验结果,建议在进行普陀水仙大规模生产时,使用低浓度的6-BA和2,4-D。 相似文献
173.
James M. Spiers 《Journal of plant nutrition》2013,36(17):2247-2261
A 6 year field study comparing the effects of 5 fertilizer sources applied at 4 levels to 3 rabbiteye blueberry (Vaccinium ashei Reade) cultivars was established on a Typic paleudult soil in southern Misssssippi. Fertilizer sources had little influence on plant height, vigor, chlorosis, or fruit yield. The first year, ‘Tifblue’ was lowest in vigor and fruit yield, but after 4 growing seasons, had the highest plant height and fruit yields. Chlorosis symptoms were more prevalent at the highest fertilization rate, in the cultivar ‘Woodard’, and with Ca(NO3)2 fertilizer. During the first 5 years, fruit yields increased as fertilization levels increased from 0 to 5.9 g N/plant but additional fertilization did not influence yields There were no differences in plant vigor due to cultivars but the highest rate of fertilization decreased vigor. The cultivar X fertilization rate interaction was significant for plant height in 1983 and for fruit yields in 1984 and 1985. ‘Delite’ and ‘Woodard’ plant height increased while height of ‘Tifblue’ decreased as fertilization rates increased from the 0 to 5.9 g N/plant levels; higher rates decreased plant height in all cultivars. In 1984 and 1985 fruit yields of ‘Woodard’ and ‘Delite’ were not influenced by fertilization but yields of ‘Tifblue’ indicated a negative response to increasing fertilizer levels. 相似文献
174.
以蓝莓品种‘蓝丰’组培苗为材料,采用正交试验设计,研究了不同类型的支撑物(珍珠岩、草炭和琼脂)、不同液体培养基(WPM、1/2WPM和1/4WPM)、不同激素(IBA、NAA、IBA+NAA)及其不同添加浓度(0.5 mg·L-1、1 mg·L-1、2 mg·L-1)对试管内蓝莓组培苗生根的影响。结果显示:以珍珠岩为支撑物的各处理有效生根率分别为82.5%、77.5%和79.31%,明显高于其他处理,且根系发达,分支多。基础液体培养基以WPM的R值最大,为44.44;激素类型以0.5 mg·L-1 IBA+0.5 mg·L-1 NAA组合的R值最大,为42.22;激素浓度以1 mg·L-1的R值最大,为43.33。蓝莓组培苗的最佳生根组合方式为以珍珠岩为支撑物,添加0.5 mg·L-1 IBA和0.5 mg·L-1 NAA的WPM液体培养基。 相似文献
175.
《Communications in Soil Science and Plant Analysis》2012,43(10):1209-1222
Cranberry leaf tissue samples were analyzed annually over a 6-year period. Vines received varied nitrogen (N) fertilizer rates and were subjected to low or high weed pressure. With few exceptions, levels of N, phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), zinc (Zn), manganese (Mn), iron (Fe), and boron (B) were sufficient during the 6-year period. Calcium and B concentrations in cranberry vines treated with low, medium, or high rates of N were greater in areas with high weed pressure than in areas of low weed pressure. Levels of Zn and Mn were higher and K was lower in tissue collected from high weed areas in 4 out of 6 years. Calcium, Mg, Zn, Mn, B, and Fe levels were negatively correlated with increasing N rate. Overall, application of various N rates did not adversely affect cranberry leaf tissue nutrient content during the first 6 years. 相似文献
176.
177.
The Jeypore tract of Orissa is one of the secondary centers of origin of cultivated rice. Recent exploration to that tract has resulted in a collection of 120 accessions of upland rice germplasm. They have been conserved in both National active collection and base collection centres for further utilisation as and when it will be required. Also a historical perspective on the genetical diversity of rice germplasm of the region has been highlighted. The characterization data revealed enormous morphological as well as agronomical variability among the landraces. 相似文献
178.
不同群体国槐种子表型变异研究 总被引:3,自引:0,他引:3
为揭示国槐(Sophora japonica L.)种子变异程度和变异规律,本试验对国槐7个群体130个单株的种子长、种子宽、种子长宽比、表面积、体积和千粒重等6个种子表型性状作了观测分析,采用平均值,变异系数,巢氏方差分析和相关分析等方法分析了表型变异及规律.结果表明:国槐种子各表型性状存在不同程度的变异,变异系数范... 相似文献
179.
180.
乌饭树叶和乌饭营养成分的分析与评价 总被引:2,自引:1,他引:2
对野生植物乌饭树叶和乌饭的营养成分进行了分析。结果表明,乌饭树叶和乌饭中分别含有多种营养成分、丰富的矿物质元素和维生素,尤其是Vc、Fe、Mn、Se、Ca含量较丰富;至少含有17种氨基酸,氨基酸总量分别为9 027 mg·hg^-1和7 121 mg·hg^-1,其中蛋氨酸、组氨酸含量较高,7种人体必需氨基酸(EAA)总量分别为3 613 mg·hg^-1和2 462 mg·hg^-1,占氨基酸总量的40.02%和34.57%。必需氨基酸中苏氨酸、亮氨酸、异亮氨酸、蛋氨酸、苯丙氨酸、缬氨酸的构成比例基本符合联合国粮农组织/世界卫生组织(FAO/WHO)的推荐标准,鲜味氨基酸(DAA)总量分别为2 212 mg·hg^-1和2 202 mg·hg^-1。 相似文献