An investigation on Lecanicillium muscarium as a biocontrol agent of stem borer pests of Rosa damascena in Kerman Province of Iran

The Rosa damascena has organic production and this plant is the most important economic crop in Kerman province. Roses have been used since the earliest times in rituals, cosmetics, perfumes, medicines and aromatherapy. The rose stem sawfly (Hartigia trimaculata) and rose stem girdler (Agrilus aurichalceus) are new and major pests of R. damascena in the Lalehzar region of Kerman province. These pests cause severe damage to plants by feeding stems and new management strategies for their control are continually being investigated. To investigate appropriate biological control agent in the region during 2005–2007, 184 isolates of fungi were collected from these pests. Isolation of fungi was achieved using standard methods. In this study, H. trimaculata and A. aurichalceus from R. damascena for the first time were recorded in Iran. Lecnicillium muscarium from H. trimaculata, L. muscarium from A. aurichalceus, Acremonium kiliense from H. trimaculata, and A. egyptiacum from A. aurichalceus have for the first time been recorded, and L. muscarium has been introduced as a suitable biological agent for control of these pests.     

The feeding behaviour of two leafhoppers on Vicia faba

Abstract.

• 1 The feeding behaviour of the two Typhlocybinae Empoasca decipiens Paoli and Eupteryx atropunctata Goetze and the nature of the damage caused to Vicia faba L. were investigated.
• 2 Sections with stylets in situ, i.e. within the plant, were obtained. Eupteryx atropunctata sucked mainly from the palisade parenchyma of the leaf, while several generations of Empoasca decipiens could also live from the stem parenchyma and pierced into phloem if this was reachable.

     

Isolation and selection of virulent isolates of Beauveria bassiana for biological control of Ommatissus lybicus in Kerman province

Date palm (Phoenix dactylifera) is the most important economic crop in Kerman province. The palm date leafhopper (Ommatissus lybicus) is one of the most important and key pests that causes high level damage to date crop. Date is an organic fruit in this area, and biological control has been introduced as the best long-term strategy in this region. To investigate appropriate biological control agents in Kerman province during 2005–2007, 178 isolates were collected from naturally infected O. lybicus for the first time recorded in the world, and Beauveria bassiana was introduced as a suitable biological control agent for control of this pest.     

Identification of fungal diseases of Rosa damascena in Kerman province of Iran

The oil rose, Rosa damascena Mill. (Rosaceae) is an agricultural crop cultivated in various countries of the northern hemisphere, such as Turkey, Bulgaria, Morocco, Iran, Egypt, France, China and India. Iran, presently, is the largest producer of rose water in world. The major production areas in Iran are Kashan, Fars, Kerman and Azerbaijan. Kerman province with 2297 hectares ha of rose gardens and 6198 tons of flower production is one of the important rose production regions. The productions of this region are organic and do not use anychemical compounds such as pesticides and fertilisers. The major fungal pathogens were studied during 2008–2010 in oil rose production areas in Kerman province, Iran. Verticillium dahlias, Rosellinia necatrix, Alternaria alternata, Seimatosporium fusisporum and Podosphaera pannosa have been detected in the oil rose from different regions in Kerman province. A. alternata has the most isolates and infected plants per cent in the oil rose. This is the first report fromVerticillium dahliae, R. necatrix, A. alternata, S. fusisporum on oil roses (R.damascena) in the world.     

Biostratigraphy of the Peri-Gondwana Cambrian trilobite fauna (northern Kerman,Iran) and correlation with other countries

Polymeroid trilobite fauna from two stratigraphic sections (Godbondar and Kuhbanan) of the Kuhbanan Formation in northern Kerman (central Iran) were studied and subjected to biostratigraphic analysis. Eleven genera and species are recognised from the latest Early Cambrian and Middle Cambrian Peri-Gondwanian successions of the study sections. The recognised fauna includes Afghanocare lategenatum, Blountia blountia, Iranoleesia sp., Iranoleesia pisiformis, Kermanella kuhbananensis, Kermanella lata lata, Kermanella lata minuta, Kermanella sp., Redlichia chinensis, Redlichia noetlingi and Redlichia sp. Based on trilobite distribution, three trilobite biozones were recognised in the study sections, namely Redlichia noetlingi biozone, Kermanella kuhbananensis biozone and Iranoleesia pisiformis biozone. The age of the study sections is late Early Cambrian to late Middle Cambrian based on the recognised trilobite biozones. The recognised late Early Cambrian trilobite assemblages (especially Redlichia and Kermanella) from northern Kerman are similar to those found from some other parts of Gondwana or Peri-Gondwana terrains (north India, Pakistan, northwestern Kashmir, Tajikistan, South Australia, South China and Afghanistan) and show affinities with fauna found in some other parts of Iran (Alborz, northern Iran; Tabas, eastern Iran; southeast Karman).     

Arbuscular mycorrhizal fungi increased early growth of two nontimber forest product species Dyera polyphylla and Aquilaria filaria under greenhouse conditions

Nontimber forest products (NTFPs) represent an important source of income to millions of people in tropical forest regions, but some NTFP species have decreased in number and become endangered due to overexploitation. There is increasing concern that the planting stocks of Dyera polyphylla and Aquilaria filaria are not sufficient to sustain the yield of NTFPs and promote forest conservation. The objective of this study was to determine the effect of two arbuscular mycorrhizal (AM) fungi, Glomus clarum and Gigaspora decipiens, on the early growth of two NTFP species, D. polyphylla and A. filaria, under greenhouse conditions. The seedlings of both species were inoculated with G. clarum or G. decipiens, or uninoculated (control) under greenhouse conditions. Percentage of AM colonization, plant growth, survival rate, and nitrogen (N) and phosphorus (P) concentrations were measured after 180 days of growth. The percentage of AM colonization of D. polyphylla and A. filaria ranged from 87 to 93% and from 22 to 39%, respectively. Colonization by G. clarum and G. decipiens increased plant height, diameter, and shoot and root dry weights. Shoot N and P concentrations of the seedlings were increased by AM colonization by as much as 70–153% and 135–360%, respectively. Survival rates were higher in the AM-colonized seedlings at 180 days after transplantation than in the control seedlings. The results suggest that AM fungi can accelerate the establishment of the planting stocks of D. polyphylla and A. filaria, thereby promoting their conservation ecologically and sustaining the production of these NTFPs economically.     

Spatial and temporal patterns of abundance of the potato leafhopper among red maples

A study was conducted in the 2001 growing season to examine the relative abundance, dispersion and distribution of the potato leafhopper (Empoasca fabae) among trees of 24 red maple (Acer rubrum) clonal selections. Yellow sticky traps hung from the trees were used to estimate the relative number of aerial potato leafhoppers among trees, starting on 1 May 2001 and stopping on 4 September 2001. More insects were collected from the east side of the plot than from the other sides in May, but no differences were significant late in the season. Few leafhoppers were collected during May, but the number of leafhoppers collected on traps rapidly increased and peaked during June. Afterwards, populations decreased and just a few individuals were trapped late in the season. Overall, significantly more leafhoppers were caught on traps hanging from trees of clone 56026 and 55410 than on trees of the other clones. Dispersion of the potato leafhopper changed from being aggregated in May, to being random in August, and also differed among the different clones. Populations tended to aggregate with increases in population numbers. Positive significant autocorrelations were detected at short distances in May, suggesting an aggregated spatial pattern early in the season. Yet, different autocorrelation patterns were detected within each block later in the season. Our results indicate that management practices could be developed to minimise pesticide use by targeting smaller areas with the highest populations at the right time of the season.     

Detection,distribution and control of Potato mop-top virus,a soil-borne virus,in northern Europe

Potato mop-top virus (PMTV; genus Pomovirus; family Virgaviridae) is transmitted by the soil-borne Spongospora subterranea f.sp. subterranea, a protoctist that causes powdery scab on potato. PMTV is distributed widely in the potato growing areas in South and North America, Japan and northwestern Europe. This article reviews the current knowledge on detection, distribution and control of PMTV with focus on the Baltic Sea region. Since the 1980s, PMTV has caused great economic losses to potato production in the Nordic countries (Norway, Sweden, Denmark and Finland), but its occurrence in other countries of the Baltic Sea region remained unknown. To fill this knowledge gap, harmonised sampling and virus detection procedures including bioassays and serological and molecular methods were employed by 21 research institutions to detect PMTV in potato tubers and soil samples in 2005–2008. Potato growing areas were widely contaminated with PMTV in the Nordic countries. Only the main seed potato production area in northern Sweden and the High Grade seed potato production zone in Finland were negative for PMTV. Intensive and systematic surveys in Poland in 2004–2008 found no evidence of PMTV, except a single PMTV-infected tuber detected in 2008. Surveys in the Baltic countries (Lithuania, Latvia and Estonia) and northwestern Russia (Leningrad province) were negative for PMTV, except infection of minitubers in a screenhouse in Latvia in 2005. Varying percentages of tubers expressing spraing symptoms in Sweden, Norway, Denmark and Poland were infected with Tobacco rattle virus, and bioassays indicated similar results for Russia. Incidence of symptomless infections with PMTV was high in tubers of many potato cultivars. Here, we discuss the contrasting patterns of distribution of PMTV in the Baltic Sea region, factors playing a role in dispersal and establishment of PMTV in new fields and means for controlling PMTV and its spread to new areas. We emphasise the use of the current virus-specific methods for the detection of PMTV in symptomless potato tubers and the high risks of disseminating PMTV to new fields and areas in viruliferous resting spores of S. subterranea in the soil adhering to seed tubers. PMTV-resistant potato cultivars will provide the only sustainable means for preventing yield losses in the infested fields and the prospects of resistance breeding are summarised.     

Comparison of egg period, hatching rate, and first-instar nymphs among three species of stonefly

Egg period was compared among several temperature conditions (11°C, 16°C, 20°C, 23°C) in Sweltsa sp., Stavsolus japonicus, and Isoperla aizuana (Plecoptera). The shortest mean egg incubation period was 27.8 days at 20°C in Sweltsa sp., 118.1 days at 16°C in Stavsolus japonicus, and 162.0 days at 20°C in Isoperla aizuana on average. Egg hatching rate was also the highest at the water temperature that provided the shortest egg incubation period. Based on laboratory data, eggs of Sweltsa sp. were considered to be deposited in May and hatched in June in the field. Thus, they must have spent the summer as nymphs in the field. Eggs of Stavsolus japonicus and Isoperla aizuana were considered to be deposited in April to May and hatched in September to October in the field. Visible eyes of Stavsolus japonicus and Isoperla aizuana appeared in August. It is likely that the long egg period of Stavsolus japonicus and Isoperla aizuana reflects that these two species spend the summer as dormant eggs in the field.     

Phocanema decipiens: Pathology in seals

Infective larvae of the anisakine nematode, Phocanema decipiens from cod (Gadus morhua), were fed to harbor seals (Phoca vitulina) and gray seals (Halichoerus grypus). At termination of the experimental infections, 6 of 8 harbor seals were infected with 34(6–64) P. decipiens, while the remaining 2 seals had relatively heavy infections of 250 and 547 nematodes, respectively; 10 of 11 gray seals were infected with 128 (68–229) P. decipiens, but only 2 nematodes were recovered from the 11th seal. Larvae and adults of P. decipiens occurred throughout the gastrointestinal tract, but mainly in the fundic portion of the stomach; the anterior extremities of the nematodes were embedded in mucosa and submucosa. Clusters of adult P. decipiens were associated with ulcerous gastric lesions in harbor seals and raised inflammatory areas in stomachs of gray seals. Singly occurring larvae from challenge transmissions were associated with raised inflammatory areas in the stomachs of both host species. Histological examinations revealed that the lesions and inflammatory areas were eosinophilic granulomata. Anisakis sp. larvae from the viscera of cod were also fed to 1 of the gray seals. Eighty of these larvae were subsequently found in association with a general inflammation in the cardiac area of the stomach in this seal. Natural anisakine infection were surveyed in 16 harbor and 53 gray seals from the Nova Scotia mainland. The natural incidence of P. decipiens was 62(5–177) in harbor seals and 577(11–1694) in gray seals. Clusters of adult P. decipiens were found in association with gastric lesions in 2 juvenile harbor seals; however, in gray seals, the nematodes neither occurred in clusters nor in association with gastric lesions.     

Fluctuations of plant pathogens in sugar factory's waste in Kerman province of Iran

Sugar beet roots and the attached soil are transferred to Bardsir factory for processing, and the roots are washed by water pressure. Muddy water flows as waste into canals and are used for irrigation of sugar beet farms. The possibility of occurrence and fluctuations of the pathogenic organisms in irrigation was studied during 2006 and 2007. The samples were collected from the wastewater once a week. Isolation of pathogens was done by four methods: (a) Citrus leaf baiting method and on PARPH selective medium, and common culture media such as: PDA, CMA, MA, NA and WA; (b) Irrigation of sugar beet seedling with wastewater; (c) Bioassay with healthy sugarbeet roots; (d) Cysts of nematode were extracted from waste by sieves. Many different pathogens were isolated from wastewater such as: Fusarium oxysporum, Fusarium solani, Rhizopus stolonifer, Penicillium digitatum, Aspergillus niger, Pythium aphanidermatum, Pythium akanoganese, Phytophthora cryptogea, Phytophthora drechsleri, Mucor sp., Rhizoctonia solani, Geotrichum sp., Erwinia carotovora and cysts of Heterodera schachtii. Pathogencity tests were done for each pathogen. During the first period of processing, the recovery of pythiaceae and Erwinia carotovora was in high level, and in the last period of processing the recovery of Penicillium digitatum, Aspergillus niger, Mucor sp. and Geotrichum sp. showed high levels. The recovery of Alternaria alternata, Rhizoctonia solani and Fusarium solani were stable but the cysts of H. schachtii were variable during the processing period. These pathogens were isolated from sugar beet farms irrigated with wastewater.     

塔里木盆地塔中台地上奥陶统海百合茎化石及其古生态*

聂拉木是西藏南部志留纪含笔石地层(石器坡组)的主要产地。近期在该地亚来村新发现一批笔石标本, 包括Normalograptus sp.、Glyptograptus sp.、Campograptus lobiferus、C. cf. lobiferus、C. cf. obtusus、C.? circularis、Lituigraptus cf. convolutus、Rastrites cf. perfectus、Stimulograptus sedgwickii、Streptograptus sp.和Torquigraptus decipiens。该组合面貌确定其属于志留系兰多维列统埃隆阶上部Lituigraptus convolutus带至Stimulograptus sedgwickii带。这一新材料的发现, 使西藏南部的志留纪地层得以作全球对比。     

甘肃省中部沿黄灌区轮作和连作马铃薯根际土壤真菌群落的结构性差异评估

甘肃省中部沿黄灌区是西北地区乃至全国重要的加工型马铃薯生产基地,然而因集约化种植带来的连作障碍问题已经严重影响到当地马铃薯种植业的可持续发展。采用大田试验与PCR-DGGE(Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis)技术相结合的方法,并通过真菌的18S r DNA序列分析,评估轮作(未连作)和连作条件下马铃薯根际土壤真菌群落在组成结构上的差异,以期为甘肃省中部沿黄灌区马铃薯连作的土壤障碍机理研究提供新证据。结果表明,同轮作相比,连作显著降低了马铃薯块茎产量和植株生物量,并且随着连作年限的延长,连作障碍也愈加严重。长期连作(6a)也导致马铃薯根冠比显著增加和植株收获指数的显著下降。在根际土壤真菌的种群数量和多样性上,连作和轮作间无显著差异,但在群落组成结构上差异明显。真菌18S r DNA测序分析进一步表明,马铃薯连作较轮作相比增加了Fusarium sp.和Fusarium solani以及Verticillium dahliae的种群或个体数量,而这些真菌是导致马铃薯土传病害的主要致病菌类型。根际土壤真菌群落组成结构的改变特别是与土传病害有关的致病菌滋生可能是导致当地马铃薯连作障碍的重要原因。     

Use of cereals as basal medium for the formulation of alternative culture media for fungi

Summary The feasibility of developing alternative media to different culture media particularly potato dextrose agar was assessed using local cereal species as the basal media. Three cereal meal extracts – corn, sorghum and millet – were prepared, using them as substitute for the potato in potato dextrose agar. Potato dextrose agar (PDA) was the standard set up with which the performances of the formulated media were compared. Eight genera of fungi (Aspergillus niger, Fusarium moniliforme, Penicillium sp., Cercospora sp., Curvularia palescens, Botryodiplopodia sp., Rhizopus sp. and Rhodotorula rubra) were isolated and pure cultures of each species aseptically inoculated onto the three different formulated media including PDA and allowed to grow. Their growths were measured at 24, 48, 72, and 96 h after inoculation, using diameter of growth as an index. The set up was repeated thrice for each species on the three formulated media and the control (PDA). Growth of all the fungal species were observed to be about the same or sometimes better in the formulated media relative to those on the standard set up, except for Rhodotorula rubra. The radius of growth of F. moniliformehad an average of 15 + 0.58 mm on corn-dextrose agar relative to 12 mm on PDA at 96 h while Cercospora sp. measured 30 + 0.58 mm on millet-meal dextrose agar relative to 37 + 1.16 mm at 48 h. Botryodiplopodia sp. grew through the whole diameter of the plate (covering the total length of the radius of 45 mm) in both sorghum-meal and PDA at 96 h.     

Searching and Oviposition Behavior of Anagrus atomus L. (Hymenoptera: Mymaridae) on Four Host Plants of Its Host, the Green Leafhopper Empoasca decipiens Paoli (Homoptera: Cicadellidae)

Anagrus atomus L. is an important egg parasitoid of the green leafhopper Empoasca decipiens Paoli. In this study the ability of the parasitoid to locate and parasitize its host was investigated on four host plants, i.e., broad beans (Vicia faba L.), sweet pepper (Capsicum annuum L.), cucumber (Cucumis sativus L.), and French beans (Phaseolus vulgaris L.). For each plant species, the behavior of the parasitoid was observed on E. decipiens infested and noninfested plants. Searching and oviposition behavior were characterized by drumming, probing, and resting. Parasitoids spent significantly less time on non-infested than infested plants, 274.5 and 875.7 s, respectively, and no probing behavior was observed on non-infested plants. Frequency of resting behavior was significantly greater on non-infested than on infested plants. Total foraging time was significantly longer on infested than on non-infested plants, indicating that A. atomus females can efficiently discriminate between leaves with and without infestation. Parasitism of A. atomus was influenced by parasitoid density, with the highest parasitism rate (64.0%) obtained at a density of 10 A. atomus females/0.1356 m² but the number of parasitized eggs per female and the searching efficiency decreased with increasing parasitoid density.     

The influence of leafhopper (Empoasca kraemeri) attack during various bean (Phaseolus vulgaris) plant growth stages on seed yield

Bean plants (Phaseolus vulgaris L.) variety Diacol-Calima, were protected with insecticides from Empoasca kraemeri R. & M. attack during various growth stages. When the leafhopper attack occurred late in the growing season, the most critical period for control was from 45–62 days after planting. When leafhopper attack was severe during the entire growing season, the period from 27–44 days was most critical, followed in importance by the 45–62-day period. Insecticidal control before 27 days and after 62 days after planting did not influence final seed yield.Leafhopper attack affected four components of yield, i.e., (1) by reducing the number of pods per plant, (2) number of seeds per pod, (3) 100-seed weight, and (4) number of empty pods per plant.

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Zusammenfassung Zikaden, deren wichtigste Art Empoasca kraemeri ist, sind die bedeutendsten Bohnenschädlinge in Lateinamerika. Es wurden zwei Experimente durchgeführt um festzustellen, in welchem Wachstums-stadium der grösste Schaden auftritt. Dazu wurde der Wachstumszyklus in vier Abschnitte unterteilt, beginnend 8 Tage nach der Saat. Die Pflanzen wurden in den verschiedenen Wachstumsstadien mit Monocrotophos (0.05%) behandelt oder zum Vergleich unbehandelt gelassen. Die Insektenpopulationen der Adulten und der Larven wurden wöchentlich (1. Experiment) und zweimal wöchentlich (2. Experiment) gemessen.Die Bohnen, die in der Zeit zwischen 8 und 26 Tagen nach der Pflanzung und nach 62 Tagen ohne Insektizidschutz gelassen wurden, erbrachten den gleichen Ertrag wie die Bohnen, die über alle vier Wachstumsstadient geschützt wurden. Im ersten Experiment, in dem der Befall durch Zikaden erst spät einsetzte, war die Zeitspanne zwischen 45 und 62 Tagen besonders kritisch. Im zweiten Experiment, in dem der Insektenbefall schon vom Saatzeitpunkt an stark war, waren die Pflanzen in der Zeitspanne von 27–44 Tagen besonders gefährdet, gefolgt von der Periode von 45–62 Tagen.Im zweiten Experiment waren alle Ertragskomponenten vom Insektenbefall beeinflusst. Der Ertragwar streng mit dem 100-Samengewicht korreliert. Wenn man zwei Ertragskomponenten berücksichtigt, war der Ertrag sehr streng korreliert mit der Anzahl voller und Prozent leerer Hülsen pro Pflanze.

     

Studies on the fungal infestation of five traditionally smoke-dried freshwater fish in Ago-Iwoye,Nigeria

Samples of traditionally smoke-dried Clarias gariepinus (Burchell), Chrysichthys nigrodigitatus (Lacepede), Sarotherodon galilaeus (Trewavas), Heterotis niloticus (Cuvier) and Heterobranchus bidorsalis (Geoffroy) were obtained from Oja Oba Market, Ago-Iwoye, Nigeria and examined for fungal infestation. The fish samples incubated on potato dextrose agar (PDA) for 7 days showed fungal infestation. Fungi isolated and identified included Mucor sp., Aspergillus sp., Rhizopus sp. and Fusarium sp. Six fungal species were isolated from C. nigrodigitatus, five each on C. gariepinus and H. niloticus. This revised version was published online in June 2006 with corrections to the Cover Date.     

Ladybird population dynamics in potato: comparison of native species with an invasive species, Harmonia axyridis

Following the detection of the harlequin ladybird, Harmonia axyridis, in 2003 in potato crops in Belgium, a study was carried out between 2004 and 2006 on the phenology of this species compared to native species in potato. The results confirmed the success of H. axyridis, with high population levels in 2004 and 2005. In 2006, aphid populations were very low and no H. axyridis larvae were sampled in potato, but the indigenous species Coccinella septempunctata and Propylea quatuordecimpunctata were detected. A species by species comparison of the date of first larvae detection, the larvae population peak, and the difference between this peak and the aphid population peak was performed. Results showed a clear correlation between C. septempunctata and P. quatuordecimpunctata and potato aphids, with a delay of 3.5 and 6.5 days between the aphid and ladybird population peaks for the two native species. H. axyridis arrived 7–8 days after the two indigenous species and the larval peak population occurred 15.8 days after the aphid population peak. This meant that H. axyridis had to complete its larval development with very low aphid populations or even with no aphids at all. The reason for its late arrival and the possible food resources used by H. axyridis larvae are discussed.     

典型生境巨菌草根内生固氮菌的群落多样性

【目的】探究不同生境巨菌草内生固氮菌群落组成多样性及其分异规律。【方法】采用高通量测序固氮酶nif H标靶基因方法,研究了我国6个典型地区的巨菌草内生固氮菌群,包括福建闽侯县、新疆墨玉县、内蒙古阿拉善左旗、青海贵德县、甘肃安定区、海南那大镇,结合地理气候因子统计,分析了固氮菌多样性的环境驱动机制。【结果】共获得64122条nif H基因的有效序列,640个OTUs,归属于6个门、10个纲、17个目、24个科、33个属和39个种。不同地区巨菌草中优势内生固氮菌群的种类和丰度存在较大的差异。在门水平上,福州闽侯县、甘肃安定区、新疆墨玉县、内蒙古阿拉善左旗和青海贵德县5个地区的优势菌门均为变形菌门,海南那大镇的优势菌门为变形菌门和蓝藻菌门;属水平上,不同地区巨菌草最优势内生固氮菌类群分别为:福州闽侯县(变形菌门中未定属,80.56%);新疆墨玉县(变形菌门中未定属,33.14%);内蒙古阿拉善左旗(变形菌门中未定属,76.23%);甘肃安定区(α-变形菌纲中的未定属,53.78%);海南那大镇(变形菌门中未定属,38.37%);青海贵德县(变形菌门中未定属,46.12%)。Alpha多样性和Beta多样性分析表明,不同地区巨菌草内生固氮菌群落的多样性存在较大的差异,海南那大镇样本中巨菌草各类内生固氮菌群的多样性及丰富度最高,福建闽侯县样本中巨菌草各类内生固氮菌群的多样性及丰富度最低。典范对应分析(CCA)结果表明,年均降雨量和年均气温是影响巨菌草内生固氮菌群变化的主要因素,其次是土壤有机质、土壤全氮和土壤p H。【结论】不同地区巨菌草内生固氮菌群落的组成及丰度存在着较大的差异,海南那大镇巨菌草内生固氮菌群的种类及相对丰度较高,本研究可为巨菌草内生固氮菌群的资源开发及其固氮微生物肥料的菌种选育和生产应用提供理论支持。