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1.
从大兴安岭长白山采集17号芥黄蜜环菌,用分离的单孢菌株进行交配型测定,证实中国该种为双因子异宗配合机制,选取各号标本的4种交配型菌株进行循环配对实验,结果发现该种的交配型基因座的多样性很高,共有13对复等位基因,证明该种在世界分布区域内具有较强的生态适应能力。是目前国际首次用实验测定的蜜环菌交配基因数目  相似文献   

2.
黑龙江省牡丹江林区蜜环菌的调查与鉴定   总被引:3,自引:0,他引:3  
在黑龙江省牡丹江地区10个林业局内进行了蜜环茵生物种的调查和标本采集,共采集分离出41个菌株,用东北5个蜜环茵生物种与之交配测定的结果表明这些菌株大部分为高卢蜜环菌,少数为CBS F。  相似文献   

3.
奥氏蜜环菌杂交双倍体子实体的人工诱导   总被引:1,自引:0,他引:1  
用产自北半球的奥氏蜜环菌Armillaria ostoyae(Romagn.) Herink单倍体菌株进行杂交,选育出25个增效交配的杂交双倍体菌株,使用3种培养料,分别在全自动和半自动人工气候室中培养诱导子实体。结果表明,在全自动人工气候室中,奥氏蜜环菌杂交双倍体产生子实体的概率是47%,而半自动人工气候室中的概率为20%。从杂交子实体中都分离到了F1代单倍体菌株。环境条件分析表明湿度是蜜环菌子实体发育的重要影响因子;培养条件分析表明蜜环菌干菌丝体可促进蜜环菌的营养生长和子实体发育。  相似文献   

4.
北半球高卢蜜环菌的遗传多样性与分子鉴定   总被引:6,自引:0,他引:6  
从北美、欧洲和中国收集23个高卢密环菌菌株,PCR扩增其rDNA的IGS和ITS区域,用AluI,HaeIII,HinfI和TagI四种限制性内切酶进行酶切,同时结合随机扩增微卫生(RAMS)多态性,对北半球的高卢蜜环菌的遗传多样性进行了分析,结果发现了高卢蜜环菌的6种IGS-RFLP图谱类型,其中gal(B)和gal(D)是国内外无报道的新的IGS-RFLP型,RFLP系统树发现该种有明显的大陆之间的遗传分化,存在中国,欧洲,北美和亚洲4个亚群体,RAMS分析表明北半球高卢蜜环菌存在亚洲,欧洲,北美-中国和北美-欧洲和北美-欧洲等4个高卢蜜环菌发育系,而且不同大陆的高卢蜜环菌具有较近的亲缘关系,而相同大陆的却具有不同的起源,特别是北美的高卢蜜环菌两个发育系异源性很高,北美东部的发育系同欧洲的关系比较近,而北西部的同亚洲关系比较近,同时表明RAMS技术是分析菌物种内遗传多样性的优越方法。  相似文献   

5.
在北京周边县区、湖北大老岭山区以及陕西安康地区分别调查栗疫病发生情况,采集病原栗疫菌(Cryphonectria parasitica)菌株并进行营养体亲和性试验.结果表明:北京板栗栽培区和陕西安康地区野生栗栗疫病发病率较高,局部地区危害严重;湖北大老岭山区栗疫病发病率低,危害轻微.北京地区菌株群体营养体亲和型多样性指数(Shannon-Wiener's diversity index)极显著低于湖北菌株群体和陕西菌株群体,而陕西与湖北菌株群体营养体亲和型多样性指数差异不显著.随机选取湖北、陕西野生栗栗疫菌部分菌株,利用特异性引物,通过普通PCR和巢氏PCR,对其交配型进行测定,发现陕西与湖北野生栗菌株群体中均存在MAT-1与MAT-2两种交配型的菌株.通过PCR扩增,在两地的野生菌株群体里均发现同时具有两种交配型基因的菌株,其中,陕西群体此类菌株比例较大,湖北菌株比例较小  相似文献   

6.
根据猪苓生长习性,结合中条山林区的自然条件和气候特点,采用蜜环菌材伴栽猪苓菌和猪苓菌材伴栽蜜环菌2种栽培方法,对猪苓仿野生栽培技术进行研究。结果表明,中条山野生猪苓菌核中分离纯化选育的Z101和Z102这2个菌株,所产苓核个大结实,色泽乌黑光亮,具有良好的栽培性状;蜜环菌材伴栽猪苓菌和猪苓菌材伴栽蜜环菌2种栽培方法,均比传统的菌核下种栽培法"窝"产量高约50%,表明采用纯菌种栽培猪苓是可行的。  相似文献   

7.
为了确定蜜环菌对榛子木材木质部和树皮部分的降解作用,以及对其成分的影响,本文对受蜜环菌降解不同时间的榛子木材的红外光谱进行研究。方法:选择蜜环菌作为侵染榛子木材的腐朽菌,以健康榛子木材和受蜜环菌腐朽40d、80d以及腐朽1年的榛子木材为研究材料,利用傅里叶变换红外光谱分析仪(FTIR)测定其红外光谱图。根据图谱中木质素、综纤维素及草酸钙官能团谱峰位置和谱峰相对吸收强度的振动变化情况,分析被蜜环菌腐朽后的榛子木材成分的变化情况。结果表明:榛子木材树皮部分和木质部中主要成分为木质素、综纤维素和一水草酸钙结晶(COM)。这3种成分均能被蜜环菌降解,并随着降解时间的改变,榛子木材成分发生不同程度的变化。其中,草酸钙可以被蜜环菌降解至含量很低,并能够在综纤维素降解时,再大量生成;另外,木质素的相关吸收峰,仅在受蜜环菌降解1年的榛子木材树皮部分发生变化,说明木质素很难被降解。  相似文献   

8.
病理原因 天麻病害的病原菌主要是真菌中除蜜环菌以外的其它担子菌,侵染与天麻共生的蜜环菌鲜材和菌材,与蜜环菌争夺养分,破坏天麻与蜜环菌之间的营养平衡,严重时不但会抑制蜜环菌的生长,降低天麻的产量,还会直接侵染天麻块茎,造成天麻腐软(称块茎软腐病)或腐烂死亡(称块  相似文献   

9.
正我国天麻生产之所以能产业化、规模化发展,归功于上世纪80年代发现萌发菌及工厂化生产的实现,及人们在科研和生产上用纯菌种培植蜜环菌菌材。天麻的有性栽培和有性繁殖既离不开蜜环菌,也离不开萌发菌。蜜环菌菌种的生产技术和配方目前已经成熟,萌发菌菌种的生产技术工艺虽趋于成熟,但其栽培种的生产及应用还有一些问题。本文现就存在的问题和规范后的技术方法简要介绍如下。  相似文献   

10.
蜜环菌(榛蘑)是东北地区传统的野生食用菌。抚顺市林科所经过3年林地栽培试验,使蜜环菌人工栽培取得成功,一次栽培可多年收获。文章论述了蜜环菌基本形态与习性、菌种分离与繁育、蜜环菌林地栽培的方法。  相似文献   

11.
Our study focuses on predicting the ultimate short-term load carrying capacity of timber-to-timber connections with dowel-type fasteners. The wide range of possible configurations in practice makes the resolution of these values by tests unrealistic. Moreover, different current regulations do not consider some specific failure mechanisms. In many countries, the reduction of resistance involved by this phenomenon is taken into account by considering an effective number of dowels (nef) smaller than the actual number of dowels (n) in the connection. However, these different regulations disagree on the values of nef and on other points (spacing, partial coefficient of security, formulas). These discrepancies in design rules invite the fundamental research on this topic and, therefore, new methods are sought in order to estimate the load carrying capacities of the connections. In the light of these, our approach consists of predicting the load carrying capacity with the neural network numerical tool. The results obtained by this analysis tool are satisfactory, although the model remains complex. Subsequently, we focus on the simplification of this numerical model with classical regression techniques in order to implement it in a design code.  相似文献   

12.
Ophiostoma species were isolated from bark beetles and Abies mariesii, A. veitchii and A. homolepis attacked by the beetles in Nikko, Tochigi, central Honshu, Japan. One to two Ophiostoma species were frequently isolated from each species of bark beetle. Ophiostoma subalpinum was the most common associate of Cryphalus montanus. Ophiostoma sp. B as well as O. subalpinum was a common fungus associated with Polygraphus proximus. Ophiostoma europhioides was isolated from Dryocoetes hectographus and D. autographus as one of the common associates. Ophiostoma sp. J and Ophiostoma sp. S were frequently isolated from D. autographus and D. striatus, respectively. These fungi seem to have specific relationships with particular bark beetles. Ophiostoma sp. B, Ophiostoma sp. J and Ophiostoma sp. S have unique morphological characteristics and appear to be new species. Five trees of A. veitchii, approximately 43 years old, were inoculated with five Ophiostoma species to assess the relative virulence of the fungi. Ophiostoma subalpinum, Ophiostoma sp. B, and O. europhioides had relatively higher virulence than the other species studied.  相似文献   

13.
Contour hedgerows of multipurpose tree species in the sloping tea lands of Sri Lanka are expected to reduce soil erosion and also add significant amounts of plant nutrients to the soil via periodic prunings. The objective of this experiment was to characterize the biomass decomposition pattern and quantify the amount of nutrients added through prunings of six tree species (Calliandra calothyrsus, Senna spectabilis, Euphatorium innulifolium, Flemingia congesta, Gliricidia sepium and Tithonia diversifolia) currently being used in hedgerows associated with tea. Withered leaf and stem prunings (50 g) were enclosed in 2-mm litter bags, placed at 5-cm depth and retrieved after one, three, six, nine and 12 weeks. Loss of initial dry weight, N, P and K was measured. Single exponential decay function adequately described both dry weight and nutrient loss. Tree species differed significantly in their rate of breakdown with decomposition constants (k) varying from 0.0299 to 0.2006 week−1 for leaves and from 0.0225 to 0.0633 week−1 for stems. Gliricidia showed the highest k for leaves with the rest in the following descending order: Senna > TithoniaEuphatorium > Calliandra > Flemingia. A similar pattern was observed for loss of all nutrients with Calliandra and Flemingia always having lower k values than the rest. Although N immobilization was not observed, immobilization of P and K was observed during the first week of incubation in some species, particularly in stem prunings. Annual biomass of prunings differed significantly between tree species in the following descending order: Calliandra > Senna > Flemingia > Tithonia > Gliricidia > Euphatorium. Calliandra added the greatest amount of nutrients annually to the soil with Euphatorium adding the least. Calliandra prunings provided the annual total K requirement and 49% of the N requirement of mature tea. However, none of the species provided more than 5% of the P requirement. It is concluded that among the tree species tested, Calliandra and Flemingia are the most suitable for contour hedgerows in tea plantations of this agroclimatic region because of their higher soil nutrient enrichment capacity and slower decomposition rates which would minimize leaching losses. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

14.
Parasitic Hymenoptera from the suprafamily Ichneumonoidea attacking the horse chestnut leafminer Cameraria ohridella Deschka & Dimic (Lepidoptera: Gracillariidae) were studied in southwest Slovakia during 2000 and 2001. The search for such species resulted in the determination of eight ichneumonid species, Gelis agilis (Fabricius), Itoplectis alternans (Gravenhorst), I. clavicornis (Thompson), I. maculator (Fabricius), Scambus annulatus (Kiss), S. brevicornis (Gravenhorst), Zatypota percontatoria (Müller), Adelognathus sp. and a braconid Colastes braconius Haliday. The most abundant species was S. annulatus. All these species recorded are polyphagous and often facultative hyperparasitoids, except C. braconius, which departs from this norm in not being hyperparasitic. The presence of more diversified native parasitoids and hyperparasitoids from the Ichneumonoidea predicate a slow successive adaptation of the parasitoid fauna to the invasive host, Cameraria ohridella.  相似文献   

15.
Baobab leaves form an important part of the local diet in Sahel countries and elsewhere in Africa. Existing leaf nutritional data and agroforestry performance information are based solely on Adansonia digitata L., the baobab of continental Africa. The introduction potential of Adansonia species from the center of diversity in Madagascar and from Australia remains untapped. To assess this potential, the mineral contents and B1 and B2 vitamin levels of dried baobab leaves were determined for five-year old trees of A. digitata, A. gibbosa (A. Cunn.) Guymer ex D. Baum, A. rubrostipa Jum. & H. Perrier (syn. A. fony Baill.), A. perrieri Capuron and A. za Baill. grown in an introduction trial in Mali. Nutritional data were evaluated against survival and vigor to identify promising germplasm. Leaf vitamin and crude protein contents were highest in the Madagascar species, especially A. rubrostipa (B1 88 mg 100 g−1, B2 187 mg 100 g−1, protein 20.7% dry weight). However, the local species far outperformed the introductions in survival, tree height, basal diameter and resistance to termites. We suggest grafting as a way of harnessing the vigor of well-adapted local baobab varieties to the superior nutritional profiles of A. rubrostipa and others. Cross-species grafting tests in Adansonia were successful, thus creating new agroforestry possibilities with different scion/rootstock combinations.  相似文献   

16.
The objective of this case study was to test the effectiveness of biocontrol for the rehabilitation of abandoned, diseased (moniliasis, witches' broom and black pod) cocoa and to develop testable hypotheses regarding the effect of shade and biocontrol timing. Three trial fields differed in their shade regimes. Biocontrol was administered starting either at flowering or pod filling. Disease incidence and yield were compared with cultural control alone. Biocontrol reduced moniliasis from 49% to 25%, independent of the shading regime and application time. Witches' broom was most severe without shade and unaffected by biocontrol. No significant effects on black pod were observed. Although biocontrol increased percentage healthy fruit independent of shading and timing, only the shaded plot with biocontrol from flowering onwards responded with increased yield. Our hypothesis is: 'In the rehabilitation of abandoned cacao, only fields under sustainable shade management and early onset of biocontrol can realise their production potential.' This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

17.
Adult fungus gnat and shore fly populations were monitored in four container nurseries near Victoria, British Columbia. In general, populations of both insects were larger in summer than in winter. Also, both insects were more abundant in the nursery with a plastic-covered, soil floor, which favored moisture accumulation and build up of algae, liverworts and mosses, than in nurseries with other types of floors such as cement. Results of fungus isolations revealed that gnats and flies both harbor the seedling pathogens Botrytis cinerea and species of Fusarium and Phoma, plus several non-pathogenic fungi. The results are discussed in relation to nursery sanitation practices, their effects on gnat and fly populations, and some possible roles of these insects in seedling disease epidemiology.  相似文献   

18.
Pavela R 《Fitoterapia》2004,75(7-8):745-749
The methanol extracts of eight species of medicinal plants were tested for insecticidal activity in third instar larvae of Egyptian cottonworm (Spodoptera littoralis). All extracts showed a certain degree of larval toxicity. The extracts of Ocimum basilicum, Origanum majorana and Salvia officinalis appeared to be highly toxic. The extracts significantly affected the growth indexes [relative growth rate (RGR), efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD)].  相似文献   

19.
A new norlignan, (2R,3R,4S,5S)-2,4-bis(4-hydroxyphenyl)-3,5-dihydroxy-tetrahydropyran (1), together with 9 known compounds were isolated from the branches and leaves of Taxodium ascendens. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidences. Methanol extract showed inhibitory activity on carbonic anhydrase II with an IC50 value of 4.27 µg/ml, acetone extract and methanol extract inhibited activity of cathepsin B with IC50 values of 2.12 and 3.71 µg/ml, respectively.  相似文献   

20.
In forest and conservation nurseries in the Pacific Northwest USA, seedling production can be limited by root diseases caused by fungi in the genera Fusarium Link:Fr., Cylindrocarpon Wollenw., Phytophthora de Barry, and Pythium Pringsh. Fusarium, Cylindrocarpon, and Pythium are the most ubiquitous, whereas incidence of Phytophthora is mostly associated with coastal bareroot nurseries. All of these root pathogens are encouraged by water saturated soils or media. Seedlings infected with Fusarium, Phytophthora, or Pythium often appear chlorotic or necrotic with extensive root decay. Cylindrocarpon often causes serious root decay without shoot symptoms. The best approach to mitigate losses from these diseases is to use a holistic integrated pest management program. This program should combine chemical controls with cultural practices, particularly those that increase soil permeability and drainage and reduce potential sources of inoculum, especially by disinfesting seeds and containers reused for crops. In general, we found that seedlings meeting nursery specifications for outplanting on forest soil (proper height, root collar diameter, healthy shoot color, lack of disease symptoms) but having these disease organisms on their root systems perform as well as non-infected seedlings.  相似文献   

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