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991.
Objective To explore and seek the best solution for the suitable high-yield tree shape and planting mode, fertilizer selection, chemical selection and other technologies of Jin Ruyi yellow hawthorn, in order to fully demonstrate the early maturity of Jin Ruyi yellow hawthorn, golden peel, fragrant and sweet flesh, and good fresh food. The advantages of new varieties such as export, Yifengyin, etc., and at the same time obtain the best yield per unit area. Method to carry out high-yield cultivation technology research through different tree shape comparison experiments, planting mode comparison experiments, fertilizer comparison experiments, and chemical comparison experiment analysis. Completion it was concluded that the trunk-shaped high-light-efficiency tree shape was adopted, supplemented by ridge cultivation, determined planting density of 2m×4m, water-saving drip irrigation, application of organic-inorganic compound fertilizer, improved fruit setting rate, and green control of pests and other measures to optimize the configuration technology. The plan can realize the early high yield of Jinruyi yellow hawthorn with high quality and stable yield year after year.  相似文献   
992.
神农架林区林下经济产业发展的思考   总被引:3,自引:0,他引:3  
笔者分析了神农架林区林下经济发展现状与存在的问题,并针对性提出相关建议,供同仁参考。  相似文献   
993.
bHLH转录因子家族是第2大转录因子家族,广泛存在于微生物、植物以及动物中。以甜橙为试验材料,通过全基因组数据库搜索鉴定,对bHLH基因进行了理化性质、系统发育、染色体分布、保守基序、蛋白互作生物信息学分析,探讨它们在不同组织的表达情况。结果表明:共鉴定出126个bHLH基因,其中112个不均匀的分布于9条染色体上,14个分布位置尚未确定;系统发育分析表明甜橙bHLH基因家族可分为16个亚家族,并且给定亚家族中的大多数基因具有相似的基因结构和保守基序。在甜橙中,多个bHLH基因相互作用共同调控其开花、光的形态发生和花色素苷合成等过程;大多数的CsbHLH基因在愈伤组织、叶、花和果实中均有表达。本研究为CsbHLH基因的功能研究奠定了基础,并有助于bHLH基因在其他植物物种中的功能研究。  相似文献   
994.
Limited plant stem elongation is hypothesized to be the primary cause of decreased plant growth in response to long‐term heavy grazing (LHG). However, it remains largely unknown how LHG‐induced changes in stem elongation are mediated by internode traits. Accordingly, we experimentally investigated the effects of LHG (defined as twice the stocking rate recommended by the local government) on plant stem elongation and internode allometry in Leymus chinensis in Xilinhot, Inner Mongolia, China. Plant size and internode traits, including internode length (IL), internode diameter (ID), and internode number (IN), from plant individuals were measured according to their phytomer position from base to apex. The results revealed that IN and their distributions were changed in response to LHG. Although LHG negatively affected IL and ID of each L. chinensis internode from base to apex and eventually stem length, the plasticity index of IL and ID increased initially and then decreased from the lowermost to the uppermost internode in response to LHG. These contrasting responses of internode traits were result of allometry between internode traits determined by both LHG and internode position. Ultimately, IL and IN were identified to be key traits influencing stem length reduction under LHG conditions and explaining 52.51% and 47.49% of variation in stem length, respectively. Overall, our findings suggest that the limitation of L. chinensis stem elongation induced by LHG is mediated by the plasticity and allometry of internode traits. This result emphasizes the sensitivity of individual plants to LHG and is potentially valuable for optimal grassland management.  相似文献   
995.
蒽酮比色法测定大豆乳清废水中总糖含量   总被引:11,自引:0,他引:11  
本文研究了用蒽酮比色法测定大豆乳清废水中可溶性总糖含量,本法可溶性总糖测定的回收率为98%~105%,标准偏差1.032×10-3,本法灵敏度高,可靠性强,误差小,而且设备简便、迅速、准确。  相似文献   
996.

Purpose

With the increase of surfactant usages, more and more concerns were paid on their effects on the physicochemical characteristics of soils. Up to now, only few researches have examined the effects of ionic surfactants on the stability of soil structure and soil water repellency.

Materials and methods

Cetyltrimethyl ammonium bromide (CTAB) as cationic surfactant and sodium dodecyl sulfate (SDS) as anionic surfactant were adopted to investigate their effects on the aggregate stability and water repellency of a silt loam soil which was sampled in Corn High-Tech Park, Huang-Huai-Hai region, China. (1) Aggregate stability: 50 g soil was mixture with 100 mL surfactant solution in a beaker. The concentrations of surfactant solutions were 0 (the blank), 200, 400, 600, 800, 1000, and 2000 mg L?1, respectively. After 30 min, the soil was sieved and divided into four fraction aggregates. (2) Soil water repellency: the concentrations of surfactant solutions were the same as experiment 1. Forty grams of soil was blended with 80 mL surfactant solution in an aluminum specimen. Drying the water by oven of 40 °C firstly and then by air, the whole period was about 1 week. After that, soil water infiltration and sorptivity were measured.

Results and discussion

Compared to the blank, surfactants increased the amounts of 2–0.25 and <0.053 mm aggregates of the soil and decreased the amounts of 0.25–0.053 mm aggregates of the soil. Surfactants also increased the mean weight diameter (MWD) of the soil. Except the 200 mg L?1 treatment, CTAB promoted the soil water infiltration. All SDS treatments impeded the soil water infiltration. The soil repellency factor (R) value of the blank was 1.22, lower than the critical value of 1.95, which implied that the soil of blank treatment was free of soil water repellency. For CTAB, only 200 and 400 mg L?1 treatment’s R were higher than 1.95 while for SDS, all the treatment’s R were higher than 1.95.

Conclusions

Surfactants improved the stability of soil aggregates. Soil treated with CTAB did not show the repellency, whereas SDS treatment resulted in intense water repellency compared with the wettable blank soil. Findings of this study can be used to explain the role of ionic surfactants on soil structure stability as well as on the development of water repellency in lower soil depths.
  相似文献   
997.
IntroductionBluefrostfoxisthehybridizedoffSpringofmalesilverfox(VUIV8sfUIvua)andfemalebluefox(AIOpexIQgOPuS)byartificialinsemination.DuetoitsspecialcharaCters,bluefroStfoxhasbeenrecognizedincommercialasafurbearersinceitwasproduced.Thefirstbluefrostfoxwasbornin1990inChi..[i].ThecolorofbluefroStfoxisverysimilartothesilverfoxexceptthatthehairisshorterthanthatofsilverfoxlzJ.ThehairStruCtureofbluefroStfoxismuchclosertothatofsilverfoxthantobindfoxl3].Hairbundlesarelargeinbluefox.Thelarges…  相似文献   
998.
Liu Dali 《林业研究》1996,7(3):73-76
Ambient noise in 13 sawmill’s workshops was tested and analyzed to reveal its character and regularity. The situation of the ambient noise in sawmill’s workshops was evaluated  相似文献   
999.
广西城市道路绿化   总被引:1,自引:0,他引:1  
通过对广西大部分城市行道树树种应用具有的优势以及存在的不足进行分析,从广西环境特征、行道树树种的特性等入手提出影响城市绿化树种选择的因素,并根据广西的具体情况针对性的提出城市道路绿化的可持续发展途径。    相似文献   
1000.
基于知识仓库的虚拟产品开发技术整合社会资源,利用web技术在不实际生产产品实物的情况下,利用模块化思想采用网络化并行设计,在产品设计初期就考虑到后续工艺和加工需求以及用户可能的附加要求,可缩短新产品开发周期。本文基于知识仓库,针对虚拟产品开发技术,分析虚拟产品技术的国内外研究现状,阐述虚拟产品开发技术的原理以及相关技术,构造虚拟产品开发的设计流程,并且基于Delphi8.0网络环境下构建基于知识的虚拟产品创新设计制造个人工作空间子系统。  相似文献   
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