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41.
为了研究赖氨酸成分对紫丁香蘑菌丝体生长的影响,采用不同浓度的赖氨酸-PDA培养基进行紫丁香蘑菌丝体生长的对比试验,确定最适合紫丁香蘑菌丝生长的赖氨酸浓度。结果表明,紫丁香蘑菌丝生长的最适赖氨酸浓度分别为30μg/mL和90μg/mL,此项研究为紫丁香蘑的规范化生长提供帮助。  相似文献   
42.
Vegetation recovery is a key measure to improve ecosystems in the Loess Plateau in China. To understand the evolution of soil microorganisms in forest plantations in the hilly areas of the Loess Plateau, the soil microbial biomass, microbial respiration and physical and chemical properties of the soil of Robinia pseudoacacia plantations were studied. In this study, eight forest soils of different age classes were used to study the evolution of soil microbial biomass, while a farmland and a native forest community of Platycladus orientalis L. were chosen as controls. By measuring soil microbial biomass, metabolic quotient, and physical and chemical properties, it can be concluded that soil quality was improved steadily after planting. Soil microbial biomass of C, N and P (SMBC, SMBN and SMBP) increased significantly after 10 to 15 years of afforestation and vegetation recovery. A relatively stable state of soil microbial biomass was maintained in near-mature or mature plantations. There was an increase of soil microbial biomass appearing at the end of the mature stage. After 50 years of afforestation and vegetation recovery, compared with those in farmland, the soil microbial biomass of C, N and P increased by 213%, 201% and 83% respectively, but only accounting for 51%, 55% and 61% of the increase in P. orientalis forest. Microbial soil respiration was enhanced in the early stages, and then weakened in the later stage after restoration, which was different from the change of soil organic carbon. The metabolic quotient (qCO2) was significantly higher in the soils of the P. orientalis forest than that in farmland at the early restoration stage and then decreased rapidly. After 25 years of afforestation and vegetation recovery, qCO2 in soils of the R. pseudoacacia forest was lower than that in the farmland soil, and reached a minimum after 50 years, which was close to that of the P. orientalis forest. A significant relationship was found among soil microbial biomass, qCO2 and physical and chemical properties and restoration duration. Therefore, we conclude that it is possible to artificially improve the ecological environment and soil quality in the hilly area of the Loess Plateau; a long time, even more than 100 years, is needed to reach the climax of the present natural forest. __________ Translated from Acta Ecologica Sinica, 2007, 27(3): 909–917 [译自: 生态学报]  相似文献   
43.
J. Q. Yan    Q. Z. Xue  Y. X. Wang 《Plant Breeding》1996,115(5):301-304
Significant differences of callus induction, green plant regeneration and culture efficiency were observed among restorer lines and their hybrids in rice. Average callus induction percentage of F1, hybrids was about twice that of their parents. Twenty doubled haploid (DH) lines that showed normal fertility with both indica and japonica CMS lines, were selected as widely compatible restorers (WCRs). TG8 derived from CPSLO17/Minghui 63 not only showed normal fertility to both indica and japonica test varieties and CMS lines, but also exhibited superior agronomic traits, in particular short plant, desired plant type, high tillerability, large panicles, good grain quality and resistance to rice blast disease. Strong heterosis for yield was observed in crosses between indica or japonica CMS lines and TG8. TG8 possessed a dominant, widely compatible gene (WCG) that was inherited from the variety CPSLO17. Results confirmed that the anther culture technique is a quick and effective way of developing widely compatible restorers in rice and that it is applicable to the direct use of intersubspecific heterosis with the three-line method.  相似文献   
44.
以渤海大学食品科学与工程学院科研实验室管理经验为依据,分别从实验室安全管理制度、安全教育及基础设施保障等方面进行详细阐述,并重点突出研究生在科研实验室管理中的作用,旨在为建设一个安全、和谐、绿色的实验环境提供安全保障,从而更好地为地方高校科研和学科建设服务。  相似文献   
45.
The oil accumulation in the developing soybean seed has been shown to be a dynamic process with different rates and activities at different phases affected by both genotype and environment. The objective of the present study was to investigate additive, epistatic and quantitative trait loci (QTL) × environment interaction (QE) effects of the QTL controlling oil filling rate in soybean seed. A total of 143 recombinant inbred lines (RILs) derived from the cross of Charleston and Dongnong 594 were used in this study to obtain 2 years of field data (2004 and 2005). A total of 26 QTL with significantly unconditional and conditional additive (a) effect and/or additive × environment interaction (ae) effect at different filling stages were identified on 14 linkage groups. Among the QTL with significant a effects, 18 QTL showed positive effects and 6 QTL had negative effects on seed filling rate of oil content during seed development. A total of 29 epistatic pairwise QTL underlying seed filling rate were identified at different filling stages. About 28 pairs of the QTL showed additive × additive epistatic (aa) effects and 14 pairs of the QTL showed aa × environment interaction (aae) effects at different filling stages. QTL with aa and aae (additive × additive × environment) effects appeared to vary at different filling stages. Our results demonstrated that oil filling rate in soybean seed were under genetic, developmental and environmental control.  相似文献   
46.
指出了邓小平"科学技术是第一生产力"的论断具有深刻的内涵,对于推动我国社会不断发展具有重要的作用。虽然不同的社会时期所凸显的社会问题有所不同,但社会问题的解决都离不开"科学技术是第一生产力"的正确指引。当前我国正处在新中国成立以来的第三次社会转型的关键时期,社会经济结构、文化形态、价值观念等都发生了深刻的变化,社会问题层出不穷,亟需得到妥善解决。立足于当前的社会状况并结合邓小平提出"科学技术是第一生产力"这一阶段的历史经验,重新解读"科学技术是第一生产力"这一思想有助于加快实现社会第三次成功转型,实现自然、社会与人类和谐发展。  相似文献   
47.
指出了锦州大气成分观测采用Grimm180在线环境颗粒物监测仪,能同时测量环境中的PM10,PM2.5和PM1,该仪器具有易于安装、操作简单、运行寿命长以及维护量少的特点。同时,Grimm180还具有自动数据备份、自动数据传输等功能。自2013年6月开始使用以来,对于雾霾等天气现象的判断识别起到重要的辅助作用。对仪器的日常维护和所出现的故障处理进行了分析和总结,以提高环境监测的效率。  相似文献   
48.
经多次实地踏查和走访调研总结,山茱萸在陕西省境内的秦巴山区15县生长具有得天独厚的优势,主要分布在陕西的汉中、商洛地区。尤其在周至、眉县、太白、佛坪、洋县、丹凤等地发现有成片的自然分布,到目前已成为药材山茱萸的主产区,2014年2月国家质检总局正式批准"周至县山茱萸"为国家地理标志的保护产品。结合各地域立地条件,特将选育的良种进行科学栽培,实现优产丰产。  相似文献   
49.
    
Soil‐water content (SWC) is a key factor in restoring degraded vegetation in alpine meadow ecosystems, but it has rarely been spatially simulated on a hectometer scale. We simulated SWC for typical dry and wet days in an alpine meadow using multivariate linear regression and autoregressive state‐space equations based on SWC and other soil, terrain, and vegetation parameters to evaluate the efficiency of these two methods in dry and wet soil‐moisture conditions. SWC measured on a typical dry day (SWC‐D) and a wet day (SWC‐W) increased and decreased with depth, respectively, and SWC‐D was similar to SWC‐W at a depth of 50 cm. Both SWC‐D and SWC‐W were significantly correlated with soil bulk density (BD), capillary porosity, silt content (Silt), gravel and stone content (GSC), pH, and organic carbon density (OCD), and both SWC‐D and SWC‐W were significantly auto‐correlated and cross‐correlated with BD, Silt, GSC, pH, and OCD at more than one lag distance. Multivariate linear regression using three variables in both dry and wet conditions had the highest accuracy, and the accuracy was generally higher for dry conditions than it was for wet conditions. The bivariate state‐space model was the most accurate for both dry and wet soil conditions, but the expression variables were totally different, with pH and OCD for dry day and BD and Silt for wet day. The conditions of soil moisture should thus be considered when choosing variables with which to simulate SWC, instead of only considering the relationships between SWC and other variables.  相似文献   
50.
    
Evaluating the regional agricultural resource endowment is an important basis for the use and management of farmland. Large‐scale farmland transfer is regarded as the prerequisite for the development of modern agriculture or scaled‐up agriculture production. However, few studies have considered the suitability evaluation of large‐scale farmland transfer in severely degraded and ecologically fragile areas. In this study, the suitability of the comprehensive quality and landscape connectivity for large‐scale farmland transfer (LFT) in Zichang County was explored. The results showed that the quality of farmland in the east and midwest was generally higher than that in other areas. High‐connectivity and moderate‐connectivity farmland were scattered along the valley pain of the Xiuyan River. Based on the evaluation results, three suitable land use types for LFT were classified. Approximately 53% (14,210 ha) of farmland distributed in eastern and midwestern Zichang County were classified as suitable for large‐scale arable land transfer; 39% (10,261 ha) concentrated in the northwestern gully zones were suitable for large‐scale garden land transfer; and 8% (1993 ha) mainly located in the north‐central and southwestern parts were unsuitable for LFT. The results are helpful for identifying suitable land use types for LFT, thus promoting rational and efficient land use.  相似文献   
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