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1.
报道我国5属:坛花兰属Acanthephippium、毛兰属Eria、沼兰属Malaxis、鸢尾兰属Oberonia、长喙兰属Tsaiorchis,5种兰科植物镶囊坛花兰Acanthephippium striatum、马齿毛兰Eria szetschuanica、小沼兰Malaxismicrotatahtha、小叶鸢尾兰Oberonia japonica、长喙兰Tsaiorchis neottianthoides在西藏、江西和湖南的新地理分布点,同时补充叉喙兰和小叶白点兰在贵州和湖南的具体分布点.凭证标本保存于中国科学院华南植物所标本馆(IBSC)和中国科学院植物所(PE)中国科学院广西植物所标本馆(IBK).  相似文献   

2.
《技术与市场》2007,(4):28-28
应用中草药预防蛇病虽然刚刚开始,在南方诸省(区)甚至全国各地的蛇场还未得到大面积的推广应用,但只是时间早晚的问题.其实,用中草药预防蛇病是一个全新的概念和途径,是生产绿色食品(蛇肉)的重要手段,也是减少蛇肉、蛇胆等抗生素残留超标的好措施.所以,用中草药预防蛇病是今后的必然趋势.  相似文献   

3.
黑鲍鱼菇是四川农业大学农学院应用微生物系教师采用细胞工程技术选育的食用菌新品种,又名晚生北风菌、冻菌、黑菇、黑鸡菇等,是北风菌中的珍品.其菌盖黑色、菌肉乌黑色、菌褶褐黑色、菌柄乌黑、基部略呈白色,子实体柄短、盖大、肉厚、质嫩,食之鲜香滑嫩、细腻爽口、具鲍鱼鲜味,口感远远超过平菇甚至凤尾菇、香菇等大多数食用菌类,是满足人们对黑色食品强烈需求的高档菇类,深受各地消费者喜爱.黑鲍鱼菇含有18种氨基酸和多种复合型维生素,含有人体必需的8种氨基酸和丰富的多糖体,富含钙、锌、铜、硒等微量元素,对增强人体免疫力、改善肾功能有非常好的作用.目前,该产品供不应求,是能给菇农带来较大经济效益的食用菌新品种.  相似文献   

4.
Leaf nitrogen resorption is very important to Phyllostachys edulis development because the withdrawn nitrogen can help newly emerging and growing culms.However, few studies have focused on the ontogenetic changes in leaf nitrogen resorption of P. edulis. Here, we examined the variability in mature leaf nitrogen concentrations(Nm), nitrogen resorption efficiency(NRE) and proficiency(NRP or Ns) and leaf-level nitrogen use efficiency(NUE) of the current-, 3 rd-and 5 th-year culms in P.edulis stands under extensive management. Analyses of variance and correlation indicated that patterns of Nm,NRP, NRE and NUE were markedly affected by culm age and leaf nitrogen status. Nm, Nsand NRE were significant higher in younger(current-year) culms with 1-year lifespan leaves, while NUE was markedly higher in older(3 rd-or 5 th-year) culms with 2-year lifespan leaves. Significant linear correlations between Nmand NRP, NRE and NUE,Nmand NUE, Nsand NRE were found for each culm age,and Nmwas significantly positively correlated to NRE for all culms pooled. Higher proficiency in older culms led to higher NUE and lower NRE, these relationships can be modulated by Nm, which in turn, is restrained by leaf N availability and acquisition. Our results revealed that at the intraspecific level, P. edulis can adjust its leaf NRE, NRP,and leaf-level NUE in concert with culm development.Understanding nitrogen resorption characteristics and NUE of P. edulis can help decision-makers design appropriate deforestation strategies and achieve precise N fertilization for sustainable bamboo forest management.  相似文献   

5.
BP and RBF neural network to predict forest stock volume were studied,but the study in evaluating both networks’ application effects was not conducted.In order to find a higher forecast precision,more strong applicative method,the comprehensive analysis and evaluation on the two methods were carried out in the practical application. By the correlation analysis,crown density,shady-slope and sunny-slope,TM1,TM2,TM3,TM5, TM7,NDVI,TM,(4-3),TM4/3 were selected as input variables,and the forest volume of Miyun County as output variables,RBF and BP neural network models for forecasting the forest volume were established.And the neural network training step length,training time,prediction accuracy and the applicability model of the two methods were comprehensively analyzed.The results show that the RBF neural network model is superior to the BP neural network model.  相似文献   

6.
Carbon management index(ICM) is used to evaluate the scientificity of soil management.Soil organic carbon(SOC) and readily oxidized carbon (ROC) contents under Leucaena leucocephala stand, Acacia glauca stand,Acacia auriculiformis stand, Azadirachta indica stand,wasteland and dry cropland were determined and their ICM were calculated.The results showed that the SOC and ROC contents under the 6 land use types were 4.22-5.92 g·kg-1 and 1.34-2.33 g·kg-1,respectively.No significant differences in SOC contents among these land uses were observed.The ROC contents under the 4 types of woodland,however,were significantly higher than these under dry cropland or wasteland(P<0.05). The ROC were high significantly(P<0.001) correlated(R2 is 66.3%) with SOC.Compared with wasteland,the ICM ranged from 1.77 to 2.36 under these woodlands,and 0.99 under dry cropland.It is revealed that the litter quantity and land management under these land uses may be the key factors resulting in the variation of ROC.At ecological fragile region of Dry-hot Valley,closure management is useful to sequestrate C in woodland soils.However,the management systems for soil carbon pool under dry cropland are not in a sound way.  相似文献   

7.
The Pine Barrens in New York State are dominated by pitch pine(Pinus ridgida) and scrub oaks(Quercus ilicifolia and Q. prinoides). With fire suppression over the last 90 years or so, P. rigida regeneration has become sparse, even in areas set aside to preserve this type of vegetation. We evaluated the effects of fire and an alternative disturbance(mechanical removal of vegetation)for increasing P. rigida regeneration in the Albany Pine Bush Preserve in eastern New York State. By comparing cover, diameter and height of P. rigida, Q. ilicifolia, Q.prinoides, and Vaccinium spp.(blueberry) growing on the sites with a known fire history, we documented structural and compositional changes in the vegetation since its establishment. We also compared sites on which Quercus sprouts were controlled through mechanical removal. In the years following a disturbance, height and cover of Q. ilicifolia increased continuously and the species became increasingly competitive. Both the density of P. rigida seedlings and Vaccinium cover decreased significantly as the diameter and height of Quercus increased. Our results confirmed that the dominance by P. rigida could be attributed to periodic fires at intervals of 20–25 years. We conclude that removing Q. ilicifolia can favor P. rigida dominance on the barren without fire by releasing pine seedlings from competition.  相似文献   

8.
Freezing and thawing indices are not only of great significance for permafrost research but also are important indicators of the effects of climate change.However,to date,research on ground-surface freezing and thawing indices and their relationship with air indices is limited.Based on daily air and ground-surface temperatures collected from 11 meteorological stations in the source region of the Yellow River,the freezing and thawing indices were calculated,and their spatial distribution and trends were analyzed.The air-freezing index(AFI),air-thawing index(ATI),ground surface-freezing index(GFI),ground surface-thawing index(GTI),air thawing-freezing index ratio(Na)and surface ground thawing-freezing index ratio(Ng)were 1554.64,1153.93,1.55,2484.85,850.57℃-days and 3.44,respectively.Altitude affected the spatial distribution of the freezing and thawing indices.As the altitude increased,the freezing indices gradually increased,and the thawing indices and thawing-freezing index ratio decreased.From 1980 to 2014,the AFI and GFI decreased at rates of 8.61 and 11.06℃-days a-1,the ATI and GTI increased at 9.65 and 14.53℃-days a-1,and Na and Ng significantly increased at 0.21 and 0.79 decade-1.Changes in the freezing and thawing indices were associated with increases in the air and ground-surface temperatures.The rates of change of the ground surface freezing and thawing indices were faster than the air ones because the rate of increase of the groundsurface temperature was faster than that of the air and the difference between the ground surface and air increased.The change point of the time series of freezing and thawing indices occurred in 2000–2001.After 2000–2001,the AFI and GFI were lower than before the change point,and the changing trend was lower.The ATI,GTI,Na and Ng during 2001–2014 were higher,with faster rates than before.In addition,the annual thawing indices composed a greater proportion of the mean annual air temperature and mean annual ground surface temperature than the annual freezing indices.This study provides the necessary basis for research on and prediction of permafrost changes,especially changes in the depth of the active permafrost layer,climate change,and possible evolution of the ecological environment over the source region of the Yellow River on the Qinghai-Tibet Plateau.  相似文献   

9.
玉参属一年生或多年生肉质草本植物,直根系,主根圆柱形,肉质表皮棕褐色,是餐馆的高档蔬菜.玉参具有清热解毒、生津止渴、补气血、助消化之功效.对气虚乏力、脾虚泄泻、神经衰弱、肺燥咳嗽有一定疗效.  相似文献   

10.
15年前,青阳县乔木乡项目林场刚栽的国外松小苗星星点点布满在3000多亩荒丘岗上,没有引起多少人注意.如今,小苗长成了参天大树,茂密的森林将这里妆扮成绵延数公里的绿海,引来了一批又一批参观的人群.据介绍,这片林木平均树高已达8米,亩均蓄积量已超过12立方米.这是我省引进世界银行贷款营建的速生丰产林中的一个典型.  相似文献   

11.
为了提高锥栗芽苗砧嫁接成活率,以野生锥栗种子作为砧木,以‘华栗3号’当年生营养枝作为接穗,采用嫩枝劈接法,研究4个嫁接时期(4月20日、5月10日、6月1日、7月10日)、5种日龄砧木(20、30、45、60、90 d)和封口材料及封口方式(铝箔、嫁接膜封顶、嫁接膜不封顶)对锥栗芽苗砧嫁接成活率的影响。结果表明:封口材料与封口方式对嫁接成活率存在较大影响,不同的封口材料与封口方式处理的嫁接苗成活率从高到低依次为:嫁接膜封顶、铝箔、嫁接膜不封顶;6月1日为最佳嫁接时期,嫁接膜封顶处理的嫁接成活率达64.00%;砧木年龄过小(20 d)或过大(90 d)均对嫁接成活不利,当砧木日龄为45 d时,嫁接成活率最高,为69.33%。  相似文献   

12.
油茶不同芽苗砧和接穗对成活率与抽梢率的影响研究   总被引:2,自引:0,他引:2  
不同砧穗芽苗砧嫁接效果各异,为了更好地提高油茶良种繁育的成活率和苗木质量,设置8个试验组合,以得出更好地砧穗组合.结果表明:砧木带种籽芽接成活率效果最好,均值为87.08%和76.04%,芽接带籽与否成活率差异不大,穗条叶片是否剪切对成活率无显著差异;砧木带种籽芽接与穗条半叶抽梢率效果最好,均值为80.00%,带籽芽接...  相似文献   

13.
【目的】通过对核桃芽接愈合过程的组织学观察,研究不同嫁接时期砧穗在愈伤组织形成、增殖和输导组织连接过程中的组织学变化机制,旨在为核桃和其他木本植物嫁接提供理论指导。【方法】以12年生核桃品种‘香玲’半木质化新梢中部芽片为接穗,2年生本地核桃实生苗为砧木,采用方块芽接法分别于砧木萌芽后40~47天和100~107天2个时间进行芽接试验,采用本课题组建立的非均质化材料切片方法对芽接愈合过程进行组织学观察。【结果】核桃萌芽后40~47天的砧穗愈合方式与前人报道一致,即形成层细胞在嫁接体愈合过程中起主导作用,愈合过程中主要组织学变化包括:隔离层的产生(3天)→砧穗形成层细胞分化产生愈伤组织(4天)→愈伤组织连接(6天)→砧穗原有形成层的修复与连接(12天),完成愈合需要12~15天,成活率达95.6%。而在萌芽后100~107天的砧穗愈合过程中,发现了与上述常规愈合不同的嫁接愈合新方式。此过程中木射线细胞起主导作用,愈合过程依次历经隔离层的产生(3天)→木射线细胞分化产生愈伤组织(4天)→砧穗愈伤组织连接(9天)→导管分化形成(15天)→新的形成层产生以及木射线的连接(25天),需要25~30天才能完成愈合,成活率为61.7%;在木射线细胞主导的砧穗愈合过程中砧木一侧的隔离层要先于接穗发生溶解,在砧穗愈伤组织完成连接时消失,而接穗表面隔离层在愈伤组织分化时依然存在,直至新的形成层产生后才完全溶解消失。【结论】核桃芽接过程中,除了常见的由形成层细胞主导的砧穗愈合方式外,还存在由木射线细胞主导的砧穗木质部的愈合新方式,木射线细胞脱分化产生愈伤组织,并进一步分化出导管、形成层和木射线等组织完成最终的砧穗连接;在此过程中愈伤组织主要来自于砧木木射线细胞且砧木隔离层要先于接穗发生溶解。  相似文献   

14.
王邦富 《湖南林业科技》2010,37(5):47-49,52
以银杏核用品种最优单株"宁银1号"为接穗,对宁化县定植12年的银杏核用低产劣质品种的盛果期幼树进行高位嫁接试验,结果表明:嫁接季节、嫁接方法和接穗的年龄、粗度、性别以及接芽部位与砧木接口粗度对嫁接成活率、当年抽梢长度具有极显著影响,但对抽梢率没有影响。嫁接成活率、当年抽梢长度以春季采用粗度为0.8 cm以上接穗的1年生顶芽、接口粗度1.0 cm砧木、嫁接方法采用截干切接或截干舌接进行高位嫁接效果最好;雌株嫁接成活率达98%以上,当年抽梢率达100%,抽梢长度达50 cm以上;雄株成活率达80%以上,当年抽梢率达100%,抽梢长度达40 cm以上。  相似文献   

15.
对半枫荷塑料大棚内嫁接育苗试验的结果表明,当年用休眠芽嫁接,翌年6月嫁接成活率可达95.07%,平均接穗高67.33 cm,平均接穗茎粗0.54 cm。砧木以3年生半枫荷I级侧枝为好,嫁接成活率、生长量、保存率由高到低排序为容器苗>移植苗>留床苗,砧木切干高度对成活率和生长量无影响。  相似文献   

16.
研究不同嫁接方法、接穗来源、砧木粗细度等对南洋楹(Paraserianthes falcataria)优树嫁接成活率的影响,结果表明:南洋楹最适宜的嫁接方法是改良切接法,优质接穗为带有饱满隐芽的1 a生木质化枝条,嫁接成活率可达到70.4%,比传统方法成活率提高51.6个百分点;南洋楹嫁接砧木的最佳地径为1.5 ~2.5cm;南洋楹的嫁接成活率随着采穗母株年龄增加有所降低.  相似文献   

17.
本试验以2年生山荆子作砧木,2年生俄罗斯花楸苗木枝条的叶芽作接穗,通过春、夏两季的嫁接试验,总结出俄罗斯花楸嫁接繁殖规律.结果表明:夏季嫁接的平均成活率为90.6%,春季嫁接的平均成活率为91.7%.春季嫁接的成活率略高于夏季,两季差异不明显.  相似文献   

18.
为给完善核桃芽接繁育技术提供参考,选用山东地方品种‘鸡爪绵’核桃实生苗为砧木,采用大方块芽接方法嫁接早实核桃品种‘香玲’和‘元林’,利用扫描电镜观测其砧穗组合体愈伤形成和嫁接口愈合过程。结果表明:2个早实核桃品种嫁接愈合过程相似,嫁接后第6天砧穗嫁接体愈合完成。第1天,嫁接口接穗上有愈伤组织细胞产生,同时有少量无机、有机分泌物或晶体;第2天,嫁接口处产生大量愈伤组织细胞,‘香玲’和‘元林’接穗愈伤组织细胞直径分别为17.5~35.0和14.1~33.3μm,‘元林’接穗愈伤细胞数量明显多于‘香玲’;第4天,愈伤细胞延伸分化出明显的愈伤组织,愈伤组织不断分裂;第5天,砧穗愈伤组织相互交叉连接;第6天,接穗和砧木间的维管束已重新连接,嫁接愈合完成。  相似文献   

19.
Patterns of shoot development and the production of different types of shoots were compared with scion leaf area index (LAI) to identify how eight clonal Actinidia rootstocks influence scion development. Rootstocks selected from seven Actinidia species (A. chrysantha Merri., A. deliciosa (A. Chev.) C. F. Liang et A.R. Ferguson, A. eriantha Benth., A. hemsleyana Dunn, A. kolomikta (Maxim. et Rupr.) Maxim., A. kolomikta C.F. Liang and A. polygama (Sieb. et Zucc.) Maxim.) were grafted with the scion Actinidia chinensis Planch. var. chinensis 'Hort16A' (yellow kiwifruit). Based on an earlier architectural analysis of A. chinensis, axillary shoot types produced by the scion were classified as short, medium or long. Short and medium shoots produced a restricted number of preformed leaves before the shoot apex ceased growth and aborted, resulting in a 'terminated' shoot. The apex of long shoots continued growth and produced more nodes throughout the growing seasons. Mid-season LAI of the scion was related to the proportion of shoots that ceased growth early in the season. Scions on low-vigor rootstocks had 50% or less leaf area than scions on the most vigorous rootstocks and had a higher proportion of short and medium shoots. On low-vigor rootstocks, a higher proportion of short shoots was retained during pruning to form the parent structure of the following year. Short parent shoots produced a higher proportion of short daughter shoots than long parent shoots, thus reinforcing the effect of the low-vigor rootstocks. However, overall effects of rootstock on shoot development were consistent regardless of parent shoot type and nodal position within the parent shoot. Slower-growing shoots were more likely to terminate and scions on low-vigor rootstocks produced a higher proportion of slow-growing shoots. Shoot termination also occurred earlier on low-vigor rootstocks. The slower growth of terminating shoots was detectable from about 20 days after bud burst. Removal of a proportion of shoots at the end of bud burst increased the growth rate and decreased the frequency of termination of the remaining shoots on all rootstocks, indicating that the fate of a shoot was linked to competitive interactions among shoots during initial growth immediately after bud burst. Rootstock influenced the process of shoot termination independently of its effect on final leaf size. Scions on low-vigor rootstocks had a higher proportion of short shoots and short shoots on all rootstocks had smaller final leaf sizes at equivalent nodes than medium or long shoots. Only later in the development of long shoots was final leaf size directly related to rootstock, with smaller leaves on low-vigor rootstocks. Thus, the most important effect of these Actinidia rootstocks on scion development occurred during the initial period of shoot growth immediately after bud burst.  相似文献   

20.
蜡杨梅与杨梅种间嫁接及亲缘关系分析   总被引:1,自引:0,他引:1  
【目的】研究蜡杨梅与杨梅的嫁接亲和性及亲缘关系,为杨梅扩展栽培提供参考。【方法】连续3年在浙江余姚滩涂上(土壤pH8. 01),以蜡杨梅和杨梅为砧木,以4种主栽品种‘荸荠种’‘东魁’‘夏至红’和‘水晶种’为接穗的种间嫁接,并基于SSR对蜡杨梅和杨梅进行亲缘关系鉴定和聚类分析。调查各砧穗组合的嫁接成活率及相关指标。【结果】杨梅砧穗组合的嫁接成活率为:70. 08%~83. 75%,其中‘夏至红’接穗的嫁接成活率最高(81. 98%),‘荸荠种’次之(80. 43%);蜡杨梅砧穗组合的嫁接成活率为27. 51%~38. 29%,其中,‘东魁’接穗的嫁接成活率最高(34. 88%);杨梅砧穗组合的嫁接成活率极显著高于蜡杨梅砧穗组合。不同组合间的T-test显示:蜡杨梅砧穗组合BQ4-6、DK4-6和SJ4-6分别在冠径、干周和植株高度等指标上显著性高于杨梅砧穗组合。6个指标的相关性分析显示:2个砧木群体在连续3年的试验中,嫁接成活率与植株高度和冠径之间均存在显著性正相关,砧木高度与植株高度均呈现显著性负相关。利用127对SSR标记对2个砧木及4个接穗材料进行了多态性检测,聚类分析后分为3个群体,蜡杨梅与杨梅的种间亲缘系数为0. 31,杨梅砧木与‘夏至红’亲缘关系最近,与‘荸荠种’次之;蜡杨梅与‘东魁’亲缘关系最近;与嫁接成活率的表现一致,亲缘关系越近成活率越高。【结论】蜡杨梅砧木与杨梅接穗间存在一定的亲和性,而且更适合生长在碱性土壤中。  相似文献   

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