杨树苗木繁殖技术          下载免费PDF全文

马方援 《农业工程》2018,8(6):129-130

杨树是一种常见大型落叶乔木，生长适应性强，可以作为纤维板生产和工业造纸的原材料，也可以使用杨树营造防风林。介绍了目前杨树苗木常用的繁殖技术手段，可为杨树繁育提供理论参考。   相似文献   

Prevalence and Countermeasures of Porcine Circovirus 3     

Feng Chunyan  Wang Caixia  Liu Dandan  Zhang Yongning  Du Fangyuan  Lin Xiangmei  Wu Shaoqiang 《畜牧与饲料科学》2018,(3)

The development history, etiology, epidemiology, clinical symptoms, pathological changes and diagnosis technology of porcine circovirus3 were summarized, and countermeasures for prevention and control of the disease were put forward based on the prevalence status in China.  相似文献   

优质水稻不育系川106 A高产繁殖技术     

钟光跃  兰发盛  吕建群  王小波  高方远  任光俊  陆贤军 《种子》2017,(10):126-128

根据川106 A亲本的生育特征和开花习性,结合5年亲本繁殖实践,总结了川106 A的高产繁殖技术.川106 A原原种提纯复壮采取"三圃四步"法.川106 A籽粒易开颖,容易携带细菌和病毒,浸泡前需使用杀菌消毒药物做浸泡处理,种子浸泡时间24 h左右,催芽温度不宜过高,35℃为宜.繁殖秧田采取提前30 d持续灌深水浸泡,消除落粒谷的效果好.繁殖中GA3施用母本时采取2次喷施法,可以使母本抽穗整齐,成熟一致.  相似文献   

Studies on Electrolyte Conductivity and Activity of Dehydrogenase of Chinese Fir and Masson Pine Bare—Root Seedling under Water and Cold Stress     

YuFangyuan XuXizeng GuoXinbao 《中国林学(英文版)》2003,5(1):30-33

The electrolyte conductivity and activity of dehydrogenase of bare-root seedlings of both Chinese fir (Cunninghamia lanceolata (Lamb.)Hook.)and Masson pine (Pinus massoniana Lamb.) under freezing and desiccation treatments were studied.The results showed that needle electrolyte conductivity of both speices increase significantly after freezing treatment and there are no significant differences in needle electrolyte conductivity between the two species.The dehydrogenase activity(ARD) of fine roots of both Chinese fir and Masson pine was negatively correlated with increasing freezing and desiccation.The results suggest that both electrolyte conductivity and dehydrogenase activity could be used as quick indicators of Chinese fir and Masson pine bare-root seedling quality.  相似文献   

杉木、马尾松种子贮藏过程中生理生化变化研究   总被引：2，自引：0，他引：2  

喻方圆  邵岚  沈永宝 《林业科学》2006,42(12):137-142

杉木(Cunninghamia lanceolata)、马尾松(Pinus massoniana)是我国南方主要造林树种,每年造林用种量很大.由于杉木、马尾松结实都存在大小年现象,大年结实量多,播种品质好,采种成本低; 小年结实量少,播种品质差,采种成本高.因此,生产上常常贮藏杉木、马尾松种子,以达到以丰补歉的目的.近年来,随着生物遗传多样性的日益被重视,作为种质资源保存措施之一,杉木、马尾松种子的长期贮藏也被提上议事日程.  相似文献   

Morphological and biochemical changes of Aesculus chinensis seeds in the process of maturation     

Fangyuan Yu  Shufen Chen 《New Forests》2012,43(4):429-440

Morphological and biochemical changes of Chinese horse chestnut (Aesculus chinensis Bge.) seeds were studied during the process of maturation. Fruit and seed diameter increased linearly from DPA (Days Post Anthesis) 60 to DPA 150 and were stable thereafter. The weight of fruit and seed increased sigmoidally between DPA 100 and DPA 160. The water contents of whole seeds, axes and cotyledons had a sharp reduction from DPA 110 to DPA 130 but changed little after DPA 130. The water contents of whole seeds, axes and cotyledons were 1.42, 1.93 and 1.30?g?g^?1DW, respectively at the end of maturation. The starch content of cotyledons from mature seeds was high on a dry weight basis (31.4%) while the total soluble sugar content varied between 12 and 20%. In both axes and cotyledons, the total soluble sugar content decreased during the process of maturation, as did all five soluble sugar components measured (glucose, sucrose, trehalose, raffinose and stachyose). Sucrose and stachyose contents remained relatively high at the time of seed maturation, followed by glucose and a trace level of trehalose. The oligosaccharide/disaccharide (O/D) ratio in the axes was 3.1 at DPA 140. The high level of sucrose and stachyose might contribute to the greater desiccation tolerance of Aesculus chinensis seeds relative to typical recalcitrant tropical seeds. High levels of ABA content in seed coats and a low GA₃/ABA ratio in both seed coats and axes might also influence the desiccation tolerance and shallow dormancy of mature Aesculus chinensis seeds.  相似文献   

天然气场站工艺系统技术改进     

于东升  郭东升  江涛  李方圆 《油气储运》2012,31(11):827-829,836,887

某天然气场站增输时,出现过滤分离系统处理能力不够、超声流量计计量数据丢失等问题,且由于该站上游为双气源供气,天然气组分波动较大,严重影响贸易计量的准确性。基于天然气杂质组成分析结果,在过滤分离器上游增设旋风分离器,并通过增加过滤分离支路,提高了天然气净化处理能力;结合场站生产实际,在进站汇管处安装在线色谱仪,解决了由于气体组分波动影响贸易计量的问题;通过在流量计与调压阀之间设置埋地工艺流程,安装T形管件和弯头,降低了节流噪音对计量的影响。  相似文献   

Influence of Mean Size on Ammonia Removal of the Aerobic Granules     

CHEN Fangyuan  NING Ping 《保鲜与加工》2012,(Z1):215-218

Aerobic granules with mean sizes of 1300μm and 900μm were seeded with nitrifying activated sludge in sequencing batch reactors (SBR) in this study. The results show that ammonia removal efficiency of the small-size granules increased to 90% within 2 weeks, while big-size granules got to the same level in 3 weeks. It is speculated that small-size granules had greater increasing nitrification rate for their bigger surface area and greater absorption ability when seeded with nitrifying activated sludge, which caused fast seeding of nitrifying bacteria in R2. Through cycle analysis, it shows that it took about 2.5h for the both reactors to remove ammonia in the system, though the nitrification rate in R1 (0.033d-1 ) is lower that that of R2 (0.033d-1 ). The higher biomass concentration in R1 (10g/l) than that in R2 (6g/l) explains. At the same, it was found that total inorganic nitrogen (TIN) removal efficiency in R1 was higher than that in R2, i.e. 64.7% vs. 57.3%, which was resulted from the bigger anoxic zone in R1.  相似文献   

苗木生理与质量研究进展   总被引：16，自引：0，他引：16  

喻方圆  徐锡增 《世界林业研究》2000,13(4):17-24

综述了矿质营养、碳水化合物含量、水分状况、生长调节物质含量、耐寒能力等苗木生理状况与质量的关系。对根生长势、电阻抗等10种苗木质量生理指标的测定方法作了简要介绍。  相似文献   

狐狸肉源性成分快速检测方法的建立     

郑方媛  周秀雯  袁望  冯涛  李素芳  潘家荣 《核农学报》2021,35(5):1154-1161

为了规范食品安全标识,防止非食用性的狐狸肉添加到肉品中导致伦理、宗教等敏感问题,迫切需要建立狐狸肉源性成分鉴定方法。本研究以狐狸、牛、羊、猪、鸭、驴和鼠肉以及模拟掺假样本为研究对象,根据狐狸线粒体基因序列设计特异性交叉引物组合,Bst DNA聚合酶反应体系经63℃恒温扩增60 min,扩增产物经电泳检测和一次性核酸试纸条检测,显示结果一致,建立了交叉引物等温扩增技术与核酸试纸条检测结合的快速检测狐狸源性成分的方法。本研究建立的狐狸肉源性成分特异性的等温扩增体系,对单一狐狸源性DNA成分的灵敏度为10 ng·μL^-1,对狐狸肉与羊肉混合物中狐狸肉成分的检出比例为1%,可为肉制品市场现场检测提供简便、经济、快速有效的技术支持。  相似文献