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71.
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分析和比较了顶坛花椒育株和不育株在营养器官形态和结构上的区别。结果表明:育株茎颜色浅紫色,皮刺基部呈圆锥形,叶面油腺点数多于不育株,叶片下表皮气孔器周围细胞排列较不育株规则;不育株茎颜色淡绿色,皮刺基部呈棱锥形,刺尖较育株短,绒毛的分布较育株多而密,茎中分泌腔数多于育株,下表皮气孔器数量明显多于育株。 相似文献
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试验结果表明,氮肥是影响花椒苗生长发育的主要因素。合理施肥可使花椒苗体内氮含量提高,氮磷比值(N/P)保持较高水平。幼苗氮含量达到5.04%,N/P接近20.当磷肥和有机肥用量多时,氮含量和氮磷比值下降,幼苗生长不良。比较好的肥料用量配比为硫酸铵〔(NH_4)_2S0_4〕152g/m~2+过磷酸钙〔Ca(H_2PO_4)_2·H_2O+CaSO_4·2H_2O〕92g/m~2+有机肥10kg/m~2,明显提高了苗木产量和质量. 相似文献
76.
花椒春夏高接换优技术试验 总被引:2,自引:0,他引:2
针对花椒春季硬枝嫁接时间较短的现状,在花椒春季硬枝嫁接的基础上开展了嫩枝高接换优试验,有效地解决了硬枝嫁接接穗不能长时间贮藏的问题.通过春夏2个季节嫁接改进了花椒嫁接技术,延长了嫁接时间,花椒嫁接后减少了花椒皮刺,减少了采摘成本. 相似文献
77.
[目的]探索青花椒护色的最佳工艺条件。[方法]选取新鲜青花椒为原料,研究了护色剂、抗氧化剂、pH和杀菌条件对护色的影响。在单因素试验的基础上,选择CuSO4浓度、VC浓度和杀菌时间3个影响较大的因素,以色差值为指标,采用响应面试验优化新鲜青花椒护色条件。[结果]新鲜青花椒的最佳护色工艺为CuSO4浓度550 mg/L、VC溶液浓度1 000 mg/L、杀菌时间20 min。在此条件下处理后的青花椒在第15天的色差为10。[结论]该研究可为青花椒的护色研究提供理论和试验依据。 相似文献
78.
以照山白杜鹃(Rhododendron micranthum)试管苗的茎段为外植体,研究不同激素组合对其外植体诱导、丛生芽增殖及试管苗生根的影响.结果表明:最适丛生芽诱导培养基为Read+ ZT 4.0 mg/L+ NAA 0.05 mg/L+蔗糖(3%),诱导率达92.41%;最适丛生芽增殖培养基为Read+ ZT 3.0 mg/L+ NAA 0.1 mg/L+蔗糖(3%),增殖系数达7.56;生根培养基为Read+ IAA 0.5mg/L+蔗糖(2%),生根率达92.5%;NAA不适宜照山白杜鹃生根诱导;将试管苗移栽到松毛土∶泥炭土∶河沙=1∶2∶1的基质中,成活率达89%. 相似文献
79.
Total extract from the fruit of Szechuan pepper (Zanthoxylum piperitum DC), the volatile components of the extract and a non‐volatile fraction containing alkylamides (NVA fraction) are feeding deterrents for rats. The present study investigated the effectiveness of these natural repellents in prairie voles (Microtus ochrogaster Wagner). Two‐choice feeding trials were conducted during which food‐deprived voles were offered choices between oat‐bran wafers. In Experiment 1, 10 voles were given three sets of feeding trials, each 2 h long. Baseline consumption was established during the first set of two trials by offering a choice between two oat‐bran wafers dipped in ethanol, the control solvent. During the second set of two trials the voles were given a choice between an oat‐bran wafer dipped in ethanol and a wafer dipped in Zanthoxylum extract. During the third set the voles were given a choice between a wafer served on top of a screened dish containing a sample of ethanol and a wafer served on top of a dish containing a sample of extract. In this manner the voles were exposed to volatile compounds emanating from the extract but could not contact it. Wafers dipped in extract were almost completely avoided. The volatile components of extract also significantly reduced food intake. In Experiment 2, habituation to the volatile constituents of extract was examined in 16 Zanthoxylum‐naïve voles. Baseline consumption was established by offering two wafers served on top of screened dishes containing ethanol. This was followed by twelve tests during which a choice between a wafer served above a sample of ethanol and a wafer served above a sample of extract was given. The voles failed to habituate to the volatile components of extract, consistently consuming less of the wafers served above extract. In Experiment 3 a dose‐response curve to Zanthoxylum extract was established, using 12 stimulus‐naïve voles. After baseline consumption was established, the animals were given two tests each, presenting a choice between a control wafer and a wafer dipped in a dilution of extract (0.001–100 g liter?1). Only concentrations of 10 and 100 g liter?1 reduced food intake. In Experiment 4 the effects of the non‐volatile fraction of extract were compared to those of whole extract. Vegetable oil was used as solvent. Eight stimulus‐naïve voles were given two tests with a choice between an oil‐dipped and an extract‐dipped wafer. A second group of eight voles received two tests with a choice between an oil‐dipped and NVA‐dipped wafer. Extract‐dipped wafers were avoided, but the NVA fraction had no effect on food consumption. Copyright © 2004 Society of Chemical Industry 相似文献
80.
不同地面覆盖对花椒冠层光能分布的影响 总被引:2,自引:0,他引:2
在陕西凤县大田生产条件下研究了种植三叶草、覆膜和覆秸秆3种地面覆盖方式对8 a生花椒林冠层光能分布的影响。结果表明,在树冠层,随高度升高,太阳总辐射、净辐射增加,地面反射辐射减小。各覆盖处理树冠下表面太阳总辐射与对照差异显著,覆膜、种植三叶草和覆秸秆林地的总辐射分别较对照低13.6%、6.4%和11.3%;树冠下表面接受的地面反射辐射差异最大,覆膜、种植三叶草和覆秸秆的林冠分别较对照高66.3%、21.4%和35.6%,树冠中部接受的地面反射辐射明显低于树冠下表面;不同覆盖处理的冠层净辐射垂直分布趋势基本一致,在冠层范围内,净辐射能的分布随高度升高呈指数规律增大。 相似文献