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91.
92.
在概述中草药穿山龙的植物学特性基础上,从无性繁殖和有性繁殖两方面阐述了其繁殖技术.包括选地、整地、栽植、田间管理及病虫害防治等人工栽培技术中的前期准备和后期田间管理技术等。 相似文献
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[目的]阐述蜈蚣兰的药用价值及生态学特性。[方法]综合有关文献对蜈蚣兰的药用价值、分布、生境、分布区气候特征及植被类型等进行综述。[结果]蜈蚣兰全草入药,具有清热解毒、润肺止咳、止血、利水通淋之功效。蜈蚣兰主要分布于我国中东部的13个省、直辖市。蜈蚣兰分布区的气候以亚热带季风气候为主,突出的特点是气候温和,雨量充沛,阳光充足,四季分明,有霜期短。分布区内的主要植被类型包括暖温性针叶林、暖温带落叶阔叶林和亚热带常绿阔叶林等。[结论]该研究为保护珍稀药用植物和研发潜在药物奠定了基础。 相似文献
96.
为研究轮作和有机肥处理对连作土壤的修复作用,以小白菜(Brassica campestris L.ssp.chinensis Makino var.communis Tsen et Lee)连作土壤为对照,比较玉米轮作,玉米秸秆还田,玉米秸秆有机肥等对连作土壤酶活性、微生物活性、活性有机碳含量及小白菜光合速率、根系活力、根系生长的影响。结果表明,轮作和有机肥处理不同程度地增加了连作小白菜光合速率、干物重、根系活力和根系ATPase活性,降低了根系MDA含量,同时提高了连作土壤酸性磷酸酶、脲酶、转化酶活性和微生物对碳源的利用能力,其中长期轮作及施用发酵有机肥的促进作用较大。相关分析表明,土壤酶活性、根系活力、活性有机碳含量、碳源利用AWCD值之间存在极显著正相关关系,说明采用合适的有机肥投入方式可以缓解连作对作物生长造成的抑制。 相似文献
97.
日本臭菘体细胞胚胎发生及植株再生体系的建立 总被引:2,自引:2,他引:0
以日本臭菘幼叶为外植体,应用均匀设计法筛选其最适合的胚性愈伤组织及胚性细胞复合体诱导、体细胞胚胎发育及植株再生的培养基配方,建立日本臭菘体细胞胚胎发生体系。结果表明,LS+6-BA 1.0 mg/L+2,4-D 2.0 mg/L+IAA 0.1 mg/L适宜日本臭菘幼叶胚性愈伤组织及胚性细胞复合体诱导,诱导率为98%;LS+6-BA 0.50 mg/L+NAA 0.10 mg/L+IAA 0.10 mg/L最适宜体胚发育及植株再生,体胚萌发率为100%,萌发的体胚在发育培养基上继续培养42 d后全部发育成完整植株。对不同阶段培养材料的形态结构及超微结构的观察证明,成功建立了日本臭菘体细胞发生及植株再生体系。 相似文献
98.
Bioavailability of Zn as affected by root-induced changes of pakchoi cultivars with different Zn efficiencies 总被引:1,自引:0,他引:1
Background, aim, and scope The Zn content in the human body is tremendously higher than that in the plant. It is vulnerable to Zn nutrition deficiency
in the human body. Those who consume less animal products are subject to Zn deficiency and mainly live in the developing regions.
The preventive measures against Zn deficiency in the human body, for example, Zn supplements from chemicals and Zn-fortified
food, are expensive and often unattainable. We have been working on finding solutions to Zn malnutrition by screening Zn-efficient
varieties of crops which can absorb more Zn from Zn-deficient soils and transfer more Zn to the edible part of crops. Pakchoi
is a popular vegetable in many parts of the world. The Zn deficiency in the human body could be rectified by consuming Zn-efficient
pakchoi cultivars. Rhizosphere is the ‘hotspot’ for plant–soil–microbe interactions, and the rhizospheric interactions play
a key role in the micronutrient acquisition. However, little attention has been paid to the rhizosphere effects of different
plant genotypes on the expression of nutrient efficiency. The aim of this study was to examine the difference of rhizosphere
effect between two pakchoi cultivars with different Zn efficiencies.
Materials and methods A Zn-deficient calcareous purple soil was collected from central China. There were two Zn treatments, one with Zn addition
(5 mg kg−1 soil) and the other, which acts as a control, with no Zn addition. Two pakchoi cultivars were Wuyueman of Zn-efficient and
Heiyoubaicai of Zn-inefficient plants. Ten seeds of each pakchoi cultivar were sown in the rhizobag. The plastic pot was filled
with 0.8 kg soil with 37% of the soil in the rhizobag. The seedlings were harvested on day 45 after planting. The rhizosphere
and bulk soil samples were analyzed for their physical and chemical properties, microbial biomass, and Zn concentrations.
Zn in the plants was also determined.
Results The cultivar Wuyueman demonstrated a much higher depletion rate of available Zn in the rhizosphere than did the cultivar Heiyoubaicai.
The available Zn in the rhizosphere of Wuyueman was lower in the rhizosphere soil (0.47 mg kg−1) compared with that in the bulk soil (1.08 mg·kg−1), and the depletion rate of available Zn was 56.5% under Zn deficiency. This was closely associated with the capacity of
cultivar Wuyueman to take up more Zn from the soil, especially under Zn-limiting conditions. The rhizosphere pH of pakchoi
cultivars was lower than that in the bulk soil, while the microbial biomass carbon in the rhizosphere was significantly higher
than that in the bulk soil. Under Zn-deficient conditions, the rhizosphere pH of the cultivar Wuyueman was lower but the microbial
biomass carbon was higher than those of the cultivar Heiyoubaicai.
Discussion Soil-available Zn was substantially depleted in the rhizosphere of two pakchoi cultivars, with the greater depletion rate
being found in the cultivar Wuyueman rather than in the cultivar Heiyoubaicai, especially under Zn-deficient conditions. This
was related to the mobilization of Zn induced by the plants with different Zn efficiencies and, thus, Zn bioavailability in
the rhizosphere. The pH decrease and the increase of microbial biomass carbon in the rhizosphere of the cultivar Wuyueman
might have contributed to the translocation of Zn in its rhizosphere, which allows Zn to be absorbed more easily by Wuyueman
than by Heiyoubaicai. This suggests that root-induced changes in the rhizosphere of pakchoi have a certain effect on the expression
of zinc efficiency.
Conclusions Root-induced changes mobilized Zn in the rhizosphere of two pakchoi cultivars and increased its bioavailability. The rate
of Zn mobilization was higher in the rhizosphere of the Zn-efficient cultivar than that of the Zn-inefficient cultivar at
low Zn levels.
Recommendations and perspectives Root-induced changes in the rhizosphere are important factors for the nutrient dynamics and, thus, also for the mineral nutrition
of plants. Soil conditions near the roots are different from those in the bulk soil. Many results have shown that these differences
depend on soil properties, fertilizer application, plant species, and other factors. Further research should focus on the
environmental effects of the rhizosphere on nutrient availability. 相似文献
99.
白菜采后衰老生理的研究 总被引:8,自引:0,他引:8
‘早油冬’白菜采后在(20±1) ℃、85%~95%相对湿度条件下贮藏时,乙烯释放量呈下降趋势,失重率迅速升高,呼吸速率先下降后上升,于第6天形成呼吸高峰。外叶叶绿素、可溶性蛋白质和类胡萝卜素含量下降比内叶快。外叶贮藏中SOD和CAT活性变化较大,4 d后迅速下降,特别是CAT活性降幅更大;POD活性先逐渐增加,6 d后急剧上升,MDA含量先缓慢增加,4 d后急剧上升,表明活性氧代谢失调,膜脂过氧化加剧。内叶SOD和CAT变化很小,并保持较高水平,POD活性无显著上升,MDA略呈下降趋势,表明活性氧的产生与清除相平衡,从而防止了活性氧积累和膜脂过氧化加强。结论:白菜的衰老是活性氧代谢失调的结果,外叶比内叶容易衰老。 相似文献
100.