化学调控剂在巨尾桉扦插育苗上应用与推广

化学调控剂在巨尾桉组培苗嫩梢扦插育苗上的应用结果表明,化学调控剂能明显延缓或抑制巨尾桉扦插苗高生长,促进地茎生长,在抑制主根生长的同时强烈促进侧根生长。施用1.0 g.m-2的化学调控剂60 d内高生长仅增加3 cm,地茎增长0.12 cm,生根条数达20~30条,出圃率达95%;而不施药的苗木60 d内高生长增加17.6 cm,地茎增长0.05 cm,生根条数仅8~12条,出圃率只有85%。应用化学调控剂能提高苗木质量和产量,起到了贮存苗木作用,使用方法简便,成本低,效果好。     

辐射松、油松幼苗抗旱性能比较

采用盆栽控水法和单因素试验设计,对两种针叶树种辐射松(Pinus radiata D.Don)、油松(Pinus tabulaeform is Carr.)幼苗在连续干旱胁迫下分别测定其植株的叶片相对含水量、质膜相对透性、脯氨酸含量和脱落酸含量等4项抗旱生理指标,以评定两种树种的抗旱性能。研究结果表明,在连续干旱胁迫下,两树种叶片相对含水量均呈下降趋势,但辐射松的降幅较大,两树种的质膜相对透性、脯氨酸含量和脱落酸含量均有所增加,但辐射松的增幅较小,因此,辐射松的抗旱性能次于油松。     

降香黄檀引种试验初报

根据降香黄檀生物学和生态学特性及仙游县的生态环境条件对其进行引种试验,初步结果表明,降香黄檀在仙游县四旁和低山(海拔高200m~300m)引种生长表现正常,造林成活率达98%以上,8个月苗高生长量达1.67m;地径达1.86cm,未发现冻害,能安全过冬,对气候适应性强,为在仙游县大力发展该树种提供科学参照。     

基于可破碎离散元法的堆石料应力变形及剪胀特性缩尺效应研究

缩尺效应对堆石料应力变形及剪胀特性有显著的影响,当前对其缩尺规律已有诸多认识,但缩尺机理仍不清晰.为进一步揭示堆石料缩尺效应产生机理,基于可破碎离散元法,通过开展不同尺寸试样的数值三轴剪切试验,探讨堆石料力学变形缩尺规律,并从宏、细观层面深入分析试样剪胀特性的缩尺规律,揭示其产生的细观机理.研究表明:试样尺寸越大,抗剪...     

种公猪睾丸阴囊肿大症的防治

加强种公猪的饲养管理和疾病防治，确保公猪精液质量，可提高母猪受胎率。若公猪发生睾丸阴囊肿大症，会引起体温升高，食欲减退或废绝，精液品质下降，导致母猪受胎率降低。病情严重的公猪将遭到淘汰，造成很大的经济损失。笔者就种公猪睾丸阴囊肿大症的病因及防治浅析如下：１病因分析１．１传染病致睾丸阴囊肿大１．１．１布鲁氏杆菌病：猪一般多为隐性感染。猪感染布鲁氏杆菌后，母猪会发生流产、死胎及娩出体弱的仔猪，流产后可发生子宫炎和不孕症，公猪会发生急性或慢性睾丸炎症、肿大。该病用血清学方法可以确诊。１．１．２放线杆菌…     

四川阿坝辐射松引种长期森林健康风险初步评估

Pinus radiata was introduced to the summer rainfall environments of Sichuan Province, China in the 1990s as a part of an afforestation pmgram for soil and water conservation in the arid and semi-arid river valley area of Aba Prefecture. Within this region a total area of 26 000 ha have been identified through climate matching as suitable and a further 63 000 ha potentially suitable for environmental plantings of P. radiata. The plantations are being established in widely separated small patches on steep and degraded slopes along the dry river valley The newly introduced P. radiata are exposed to two kinds of forest health risks： they may be attacked by （a） indigenous pathogens and pests against which they may not possess any resistance or （b） by inadvertently introduced foreign pests or pathogens. This paper presents a survey of the potential damaging pests and a preliminary assessment of forest health risks facing the P. radiata plantations over a much longer timeframe than the initial phase of introduction and early plantation establishment. An empirical appmach was adopted to evaluate forest health risks by a combination of literature review, examination of historical records of pest and disease outbreaks in the surrounding conifemus forests, field surveys and inspections, specimen collection and identification, and most importantly, expert analysis of the likelihood of attack by specific pests and pathogens and the subsequent impact of such attacks. The assessment identified some specific forest health risks to the long-term success of P. radiata introduction in this area. These risks are closely associated with the indigenous pests and pathogens of the two native pine species, P. tabulaeformis and P. armondii since these pests and pathogens are considered more likely to establish on P. radiata over time. Exotic pests and pathogens are of a quarantine concern at present. Based on the results of assessment, recommendations are pmvided to improve forest vigour and to reduce the forest health risks pos     

薄壳山核桃大砧木嫁接技术

薄壳山核桃是世界著名的干果。大砧木嫁接是良种繁育、品种改良、嫁接授粉树的重要技术手段。该文介绍了接穗的采集时期和贮藏,嫁接部位和＂放水＂方法,嫁接时期和嫁接方法,嫁接后的管理等方面的成功技术和经验。     

某猪场猪链球菌病的防治

龙海市某猪场，２００２年３月２０日至３月２５日，有９５头菜猪发病，死亡９头，病死率９．５％。经检查确诊为猪链球菌病。现报道如下：１发病情况该批菜猪未进行链球菌苗免疫、而且饲养密度过高，猪舍高度不够，通风设备及条件略差，舍内氨味较浓，致使猪体抵抗力降低。特别今年闽南地区春季严重干旱，气温比往年高，场主忽视通风、降温，导致链球菌病早发。从３月２０日至３月２５日，９５头菜猪发生链球菌病，死亡９头。其流行特点为：发病早、传染快、死亡率高。２临床症状病猪病初体温多数在４１℃以上，部分病猪为４０℃～４１℃，…     

干旱地带侧柏幼林地绿肥种植研究

经过连续4a在干旱地带抗逆性树种侧柏幼林地上利用雨季种植绿肥压青,增加土壤肥力,提高水分利用率,促进幼树生长研究,结果表明:(1)种植红豆草的土壤0~40cm含水量旱季增加3.68g.kg-1,0~20cm土壤容重降低0.07g.cm-3;种植草木樨土壤0~40cm含水量旱季增加4.18g.kg-1,0~20cm土壤容重降低0.05g.cm-3;种植沙打旺土壤0~40cm含水量增加2.46g.kg-1,0~20cm土壤容重降低0.18g.cm-3。(2)种植绿肥压青,土壤有机质增加0.37g.kg-1~0.55g.kg-1,土壤CaCO3含量下降0.66g.kg-1~1.36g.kg-1,有效氮增加4.5mg.kg-1~18.5mg.kg-1,有效磷含量增加1.0mg.kg-1~3.46mg.kg-1,CEC比对照增加0.54mg.kg-1~0.58mg.100g-1。(3)种植红豆草、草木樨、沙打旺绿肥压青对抗逆性树种侧柏树高、地径生长有显著的促进作用,尤其种植红豆草的侧柏幼树生长最好,高、径生长为对照的1.7倍和1.6倍。     

干旱地带辐射松整地造林研究

经过连续3年采用不同的整地方式对辐射松(Pinus radiataD.Don)造林及幼林生长的试验研究,结果表明:(1)干旱地带采用水平沟、短册状整地比穴状整地造林成活率提高2.4~7.8个百分点,保存率提高1.0~7.6个百分点,高生长量提高7.8 cm~28.4 cm,地径生长量提高0.28 cm~0.84 cm。(2)水平沟整地比短册状、穴状整地0~100 cm土壤含水量全年分别提高1.29个百分点和2.08个百分点,旱季分别提高1.36个百分点和1.37个百分点,雨季分别提高1.16个百分点和2.87个百分点;短册状整地比穴状整地0~100 cm土壤含水量全年提高0.80个百分点,旱季提高0.01个百分点,雨季提高1.72个百分点。