无菌培养条件下不同基因型小麦耐盐性及其生理机制研究

以4种不同基因型小麦(小偃6号、NR9405、RB6和陕229)种子为材料,研究组培条件下盐胁迫对小麦种子活力、幼苗生物量、保护酶活性、亲合性渗调物质以及Na+、K+ 含量等的影响.结果表明:盐胁迫下,小麦幼苗的生长均受到不同程度的抑制,表现为发芽率、根长、芽长、生物量随着盐浓度的升高而明显下降,并存在显著的基因型差异.盐胁迫下小偃6号与NR9405的生物量显著高于陕229与RB6;小偃6号与NR9405的超氧化物歧化酶(SOD )活性均随着盐浓度的增大而升高;RB6和陕229在0～150 mmol/L盐浓度下SOD酶活性升高,而在2 00 mmol/L盐浓度时,SOD活性急剧下降.随着盐浓度的升高4种不同基因型小麦体内游离脯氨酸累积量增大,在200 mmol/L时RB6的累积量显著高于其它基因型.随着盐浓度的升高,幼苗体内的Na+含量增加,K+含量下降,Na+/K+比值增大.小偃6号和NR9405的耐盐性优于陕229与RB6.     

3种盐胁迫对玉米幼苗生长及叶片抗氧化酶和离子累积的影响

选取2个玉米品种(金玉819和金单999),探讨了3种盐胁迫(NaCl、Na_2SO_4和NaNO_3)对玉米幼苗生长、抗氧化酶活性以及叶片中K~+、Na~+、Ca~(2+)累积的影响。结果表明:3种不同类型的盐胁迫均会导致玉米幼苗鲜重下降,地上部鲜重金玉819下降超过28.6%,金单999下降超过18%;盐胁迫下金玉819叶片SOD酶活上升2.1倍以上, POD酶活性最高上升4.5倍,APX最高上升2.1倍,CAT最高上升2.2倍;金单999叶片SOD酶活最高上升2.1倍,APX最高上升1.6倍,CAT最高上升1.9倍。2个基因型玉米胁迫下叶片内Na~+含量上升4.5～6.3倍;NaCl和NaNO_3处理下,K~+/Na~+比对照降低90%～93%,而Na_2SO_4处理下K~+/Na~+下降78%～82%,金玉819和金单999的Ca~(2+)/Na~+比对照分别降低了85%～90%和92%～94%。综合分析表明NO~-_3引起的次生盐害对玉米生产危害较大。与金单999相比,金玉819对盐胁迫更加敏感,相同Na~+浓度处理下,金玉819的鲜重和SOD酶活性下降显著且拥有较低的K~+/Na~+和Ca~(2+)/Na~+值。     

NaCl胁迫对枸杞叶绿素荧光特性和活性氧代谢的影响

对枸杞幼苗进行不同浓度(NaCl)处理后的荧光特性和活性氧代谢的研究结果表明:随着浓度的升高,叶绿素荧光参数Fv/Fm,Fv/Fo,фPSII呈降低趋势,非光化学猝灭效率(NPQ)在轻度胁迫时有所升高,随着盐浓度的加重使NPQ下降;随着盐浓度地升高,保护酶SOD、POD、CAT活性有不同程度地升高,但是H2O2含量和O2-.产生速率也增高,说明枸杞叶片活性氧不能及时清除而造成光合速率的下降,从而使光合机构受到破坏,同时也说明枸杞幼苗对NaCl轻度胁迫(0.3%)和短期胁迫(4d)有一定的适应能力。     

水分和铅交互胁迫对侧柏幼苗抗氧化酶活性的影响

通过盆栽实验研究一年生侧柏(Platycladus orientalis)在不同水分处理(土壤相对含水率为40%、60%、80%、100%)及重金属铅五个胁迫水平(0、300、500、1000、2000mg·kg-1)交互作用下抗氧化酶活性(POD、SOD)和丙二醛(MDA)含量的变化。结果表明:在水分和铅的交互胁迫下,侧柏幼苗叶片POD、SOD活性均表现为先升后降的趋势,不同水分胁迫条件下侧柏幼苗叶片POD、SOD活性均在铅含量为500mg·kg-1时达到最大值,在铅含量<500mg·kg-1时,不同水分胁迫条件下侧柏幼苗叶片POD、SOD活性都随着铅胁迫的增大逐渐上升,在铅含量>500mg·kg-1时,不同水分胁迫条件下侧柏幼苗叶片POD、SOD活性都随着铅胁迫的增大逐渐下降。在水分和铅的交互胁迫下,侧柏幼苗叶片MDA含量逐渐升高,在铅含量<1000mg·kg-1时,不同水分胁迫条件下侧柏幼苗叶片MDA含量变化不明显,在铅含量>1000mg·kg-1时,不同水分胁迫条件下侧柏幼苗叶片MDA含量逐渐上升。适当的交互胁迫(铅含量500mg·kg-1,60%水分处理)有利于提高侧柏的抗逆性。     

NaCl胁迫对文冠果生长及生理生化指标的影响

以盆栽1年生文冠果幼苗为试材,采用不同浓度NaCl溶液(0.0%、0.1%、0.2%、0.4%、0.6%、0.8%)对文冠果幼苗进行盐胁迫处理,测定了胁迫处理下文冠果幼苗株高、地径、生物量、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、抗坏血酸酶(APX)活性、质膜透性、脯氨酸含量、丙二醛(MDA)含量等指标,研究了不同程度NaCl胁迫对文冠果幼苗生长和生理特性的影响。结果表明:随着NaCl浓度的提高,文冠果幼苗的株高生长量、地径生长量、地上部分和根及全株干质量均呈显著下降趋势(p<0.05);随着NaCl浓度的升高,文冠果叶片SOD活性呈先上升后下降趋势,在0.4%Na CI处理下SOD活性达到最大值;过氧化氢酶活性、抗坏血酸酶活性呈显著下降趋势(p<0.05);而相对电导率、脯氨酸含量、MDA含量呈升高趋势。总体看来,低浓度的NaCl胁迫对文冠果幼苗生长的抑制作用不明显,而较高浓度的NaCl胁迫则具有明显的抑制作用。在试验处理结束后,供试文冠幼苗并没有全部死亡且大多数能够存活,结合各项指标检测结果,可以初步断定文冠果对Na CI胁迫具有较强的耐受性。     

水分胁迫对文冠果幼苗生长及生理特性的影响

以1年生文冠果(Xanthoceras sorbifolia Bunge)幼苗为试材,通过盆栽控水试验设置3个水分处理:对照、干旱胁迫和水涝胁迫,研究了不同程度水分处理对文冠果幼苗生长和生理特性的影响。结果表明:1)水分胁迫下文冠果幼苗地上生物量、根生物量和总生物量显著下降,根冠比显著增大(P<0.05)。2)与对照相比,干旱胁迫下文冠果叶片SOD活性、MDA含量、脯氨酸含量和相对电导率显著升高,分别比对照上升了43.4%、4.1%,86.8%和12.3%;而CAT活性显著下降,比对照下降了37.2%。3)与对照相比,水涝胁迫下文冠果叶片MDA含量、脯氨酸含量和相对电导率显著升高,分别比对照上升了19.8%、50.2%和20.5%;SOD活性、CAT活性显著下降,分别比对照下降了13.9%、55.8%。综合指标分析认为,文冠果对水分胁迫具有较强的忍耐力。     

铅胁迫下干旱对国槐和紫穗槐幼苗抗氧化酶活性的影响

为了阐明铅胁迫下国槐和紫穗槐对干旱的生理响应机制,进而对比两者在铅胁迫下的抗旱性,为西北矿区耐铅型抗旱植物鉴选提供依据。通过盆栽试验,以1年生的国槐和紫穗槐幼苗为材料,以土壤相对含水量(SRW)100.00%的无铅处理为对照,其余处理外源铅浓度统一设为2 000 mg·kg~(-1),测定不同水分胁迫强度(土壤相对含水量87.84%,70.00%,52.16%,40.00%)国槐和紫穗槐幼苗叶片中超氧化物歧化酶(SOD)、过氧化物酶(POD)以及过氧化氢酶(CAT)活性的变化。结果表明:单一铅胁迫(2 000 mg·kg~(-1))下国槐和紫穗槐抗氧化酶活性高于对照;铅和干旱复合胁迫下,SRW 87.84%、SRW 70.00%、SRW 52.16%的处理,随着干旱胁迫强度的升高,国槐幼苗叶片SOD、POD和CAT活性均呈先升高后降低趋势且高于对照,紫穗槐SOD和POD活性呈先升高后降低趋势且高于对照,而CAT活性呈先降低后升高趋势;SRW为40%的处理下,国槐的SOD和CAT活性显著低于对照,POD活性略高于对照;紫穗槐SOD、POD和CAT活性均高于对照。铅胁迫(2 000 mg·kg~(-1))对国槐和紫穗槐的抗氧化酶有激活作用;铅胁迫下,紫穗槐对干旱的抗性强于国槐。     

盐胁迫对不同基因型玉米生理特性和产量的影响

选用两种不同的玉米品种登海9号及浚单18,在不同大田盐浓度下生长,测定它们的产量以及在实验室通过不同浓度的盐胁迫测定它们的叶绿素含量、净光合速率、根系活力及生长量,以了解盐胁迫对不同基因型玉米生理特性和产量的影响。结果表明,在大田不同盐浓度土壤栽培的玉米,随着盐浓度的增加产量逐渐降低,并且盐敏感玉米浚单18的降低幅度大于抗盐品种登海9号。盐胁迫条件下,玉米的叶绿素含量、净光合速率、根系活力及生长量均随着盐胁迫浓度的提高而逐渐降低,并且耐盐品种登海9号的降低幅度小于盐敏感品种。     

PP333对干旱胁迫下马铃薯幼苗抗旱性及块茎营养的影响

探讨了干旱胁迫下叶面喷施多效唑(PP333)对马铃薯幼苗抗旱生理及块茎营养的影响,结果表明在幼苗的生长发育方面,干旱胁迫下叶面喷施PP333相对降低了植株的株高、单株结薯数和地上部分的生物量,增加茎粗和薯均重,显著提高叶片脯氨酸和可溶性糖含量,使干旱胁迫下叶片含水量和叶绿素含量下降幅度减小,显著提高SOD活性,抑制叶片相对电导率和MDA含量升高的幅度;叶面喷施PP333还显著提高了马铃薯幼苗对极端干旱的适应能力.在块茎营养方面,干旱胁迫下叶面喷施PP333提高了块茎中淀粉、蛋白质、还原糖、维生素C及干物质含量.可见PP333能显著提高马铃薯幼苗的抗旱性和块茎营养.     

4种不同石竹属植物的抗旱性分析

以瞿麦(Dianthus superbus L.)、常夏石竹(Dianthus plumarius)、中国石竹(Dianthus chinensis L.)和须苞石竹(Dianthus barbatus L.) 4种不同石竹属植物幼苗为试材,采用自然干旱胁迫法对其进行处理,测定不同干旱胁迫下石竹幼苗的形态和生理指标,并用隶属函数法对4种石竹属植物的抗旱性进行综合评价,旨在筛选出适合山西省栽培和利用的石竹属抗旱性种质资源。研究结果表明:随着干旱胁迫程度的加剧,4种石竹属植物幼苗的土壤含水量和叶片相对含水量均下降,处理第12 d时各处理组叶片相对含水量和对照相比分别下降64.14%、59.44%、80.84%和78.58%;丙二醛(MDA)含量第10 d时处理组和对照组相比上升451.61%、353.45%、724.32%和647.95%;处理组和对照组相比超氧化物歧化酶(SOD)活性在第8 d分别上升77.58%、90.68%、29.05%和81.52%;脯氨酸(Pro)含量持续上升,叶绿素(Chl)、可溶性蛋白质含量以及超氧化物歧化酶(SOD)的活性呈先上升后下降的趋势;干旱胁迫处理第10 d时,Dt SOD和Dt POD基因在常夏石竹和瞿麦中表达水平较高,分别为对照组的2.5倍和2.25倍。利用隶属函数法分析得出4种不同石竹属植物的抗旱性从强到弱依次为:常夏石竹瞿麦须苞石竹中国石竹。     

Dermestid beetles in ‘evolution Canyon’, lower Nahal Oren, Mt. Carmel, including new records for Israel

Fifteen species of dermestid beetles were recorded at ‘Evolution Canyon’ (EC), Lower Nahal Oren, Mt. Carmel, Israel. They represent ~35% of known Israeli dermestid species. The following three species were recorded for the first time in Israel:Trogoderma svriaca Dalla Torre, 1911;Ctesias svriaca Ganglbauer, 1904; andAnthrenus (s.str.) jordaniens Pic, 1934. Adults of 13 species were collected on the more solar radiated, warmer and climatically more fluctuating south-facing slope (SFS); ten species were collected on the opposite, north-facing slope (NFS), which was cooler and climatically more stable. The abundance of adult dermestid beetles was 1.9 times higher on the SFS than on the NFS (86 and 47, respectively). Species richness and abundance distribution at EC (three collecting stations on each slope and one at the valley bottom) were significantly negatively correlated with the plant cover that consisted of trees and bushes (Spearmanr _s ,P=0.007 and 0.039, respectively) and perennials (Spearmanr _s ,P=0.039 and 0.077, respectively), indicating that non-woody plants were preferred by adult dermestid beetles.     

Epidemiology of Toxigenic Fungi and their Associated Mycotoxins for Some Mediterranean Crops

Recent data on the epidemiology of the common mycotoxigenic species of Fusarium, Alternaria, Aspergillus and Penicillium in infected or colonized plants, and in stored or processed plant products from the Mediterranean area are reviewed. Emphasis is placed on the toxigenicity of the causal fungal species and the natural occurrence of well known mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes, zearalenone, patulin, Alternaria-toxins and moniliformin), as well as some more recently described compounds (fusaproliferin, beauvericin) whose toxigenic potential is not yet well understood. Several Fusarium species reported from throughout the Mediterranean area are responsible of the formation of mycotoxins in infected plants and in plant products, including: Fusarium graminearum, F. culmorum, F. cerealis, F. avenaceum, F. sporotrichioides and F. poae, which produce deoxynivalenol, nivalenol, fusarenone, zearalenone, moniliformin, and T-2 toxin derivatives in wheat and other small grains affected by head blight or scab, and in maize affected by red ear rot. Moreover, strains of F. verticillioides, F. proliferatum, and F. subglutinans, that form fumonisins, beauvericin, fusaproliferin, and moniliformin, are commonly associated with maize affected by ear rot. Fumonisins, were also associated with Fusarium crown and root rot of asparagus and Fusarium endosepsis of figs, caused primarily by F. proliferatum. Toxigenic A. alternata strains and associated tenuazonic acid and alternariols were commonly found in black mould of tomato, black rot of olive and citrus, black point of small cereals, and black mould of several vegetables. Toxigenic strains of A. carbonarius and ochratoxin A were often found associated with black rot of grapes, whereas toxigenic strains of A. flavus and/or P. verrucosum, forming aflatoxins and ochratoxin A, respectively, were found in moulded plant products from small cereals, peanuts, figs, pea, oilseed rape, sunflower seeds, sesame seeds, pistachios, and almonds. Finally, toxigenic strains of P. expansum and patulin were frequently found in apple, pear and other fresh fruits affected by blue mould rot, as well as in derived juices and jams.     

Hymenopteran Parasitoids on Fruit-infesting Tephritidae (Diptera) in Latin America and the Southern United States: Diversity, Distribution, Taxonomic Status and their use in Fruit Fly Biological Control

We first discuss the diversity of fruit fly (Diptera: Tephritidae) parasitoids (Hymenoptera) of the Neotropics. Even though the emphasis is on Anastrepha parasitoids, we also review all the information available on parasitoids attacking flies in the genera Ceratitis, Rhagoletis, Rhagoletotrypeta, Toxotrypana and Zonosemata. We center our analysis in parasitoid guilds, parasitoid assemblage size and fly host profiles. We also discuss distribution patterns and the taxonomic status of all known Anastrepha parasitoids. We follow by providing a historical overview of biological control of pestiferous tephritids in Latin American and Florida (U.S.A.) and by analyzing the success or failure of classical and augmentative biological control programs implemented to date in these regions. We also discuss the lack of success of introductions of exotic fruit fly parasitoids in various Latin American countries. We finish by discussing the most pressing needs related to fruit fly biological control (classical, augmentative, and conservation modalities) in areas of the Neotropics where fruit fly populations severely restrict the development of commercial fruit growing. We also address the need for much more intensive research on the bioecology of native fruit fly parasitoids.     

A survey of the genera of<Emphasis Type="Italic">Microgaster</Emphasis> latreille and<Emphasis Type="Italic">Hygroplitis</Emphasis> thomson (Hymenoptera: Braconidae: Microgastrinae) from China

The genera ofMicrogaster Latreille 1804 andHygroplitis Thomson 1895 from China are presented systematically in this paper. Thirty-two species ofMicrogaster and three species ofHygroplitis are known in China. Diagnosis, character variation, distribution and host of each species among the two genera are presented, including its host and distribution. Keys to the species ofMicrogaster andHygroplitis are given. http://www.phytoparasitica.org posting Dec. 19, 2006.     

Plant Viruses Transmitted by Whiteflies

One-hundred and fourteen virus species are transmitted by whiteflies (family Aleyrodidae). Bemisia tabaci transmits 111 of these species while Trialeurodes vaporariorum and T. abutilonia transmit three species each. B. tabaci and T. vaporariorum are present in the European–Mediterranean region, though the former is restricted in its distribution. Of the whitefly-transmitted virus species, 90% belong to the Begomovirus genus, 6% to the Crinivirus genus and the remaining 4% are in the Closterovirus, Ipomovirus or Carlavirus genera. Other named, whitefly-transmitted viruses that have not yet been ranked as species are also documented. The names, abbreviations and synonyms of the whitefly-transmitted viruses are presented in tabulated form together with details of their whitefly vectors, natural hosts and distribution. Entries are also annotated with references. Whitefly-transmitted viruses affecting plants in the European–Mediterranean region have been highlighted in the text.     

Brief Guide for Authors

正Journal of Arid Land(JAL)is an international journal(ISSN 1674-6767;CN 65-1278/K)for the natural sciences,sponsored by the Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences and Science Press.It is published by Science Press and Springer-Verlag Berlin Heidelberg bimonthly.JAL publishes original,innovative,and integrative research from arid and semiarid regions,ad     

Broad bean mottle virus in Morocco; curculionid vectors,and natural occurrence in food legumes other than faba bean (Vicia faba)

Broad bean mottle virus (BBMV) was transmitted from infected to healthy faba-bean plants by the curculionid weevilsApion radiolus Kirby,Hypera variabilis Herbst,Pachytychius strumarius Gyll,Smicronyx cyaneus Gyll, andSitona lineatus L. The latter appeared to be an efficient vector: acquisition and inoculation occurred at the first bite, the rate of transmission was c. 41%, and virus retention lasted for at least seven days.S. lineatus transmitted the virus from faba bean to lentil and pea, but not to the three genotypes of chickpea tested. This is the first report on the generaHypera, Pachytychius, andSmicronyx as virus vectors, and onA. radiolus, H. variabilis, P. strumarius, andS. cyaneus as vectors of BBMV.Out of 351 samples of food legumes with symptoms suggestive of virus infection, 16, 11, 19, and 17% of the samples of chickpea, lentil, pea, and common bean, respectively, were found infected when tested for BBMV in DAS-ELISA. This is the first report on the natural occurrence of BBMV in chickpea, lentil, pea, and common bean. The virus should be regarded as a food-legume virus rather than a faba-bean virus solely, and is considered an actual threat to food legume improvement programmes.     

Characterization of potato potyvirus Y (PVY) isolates from seed potato batches. Situation of the NTN, Wilga and Z isolates

A collection of 38 PVY isolates from seed potato batches, originating from several Western European countries, was characterized by using current biological, serological and molecular tools differentiating PVY strains and groups. The correlation between the three kinds of tests was good but not absolute. No single serological or PCR method was able to discriminate among the five isolate groups found. Twenty-nine isolates belonged to the PVY^N strain and six to the PVY^O strain. No PVY^C was found. Two other isolates reacted serologically like PVY^O, but were unable to elicit a hypersensitive response from the Ny_tbr gene and probably represent the PVY^Z group. At the molecular level, these two isolates showed a combination of both PVY^O and PVY^N and could be recombinants of these strains. Another isolate reacted serologically like PVY^O, but induced vein necrosis in tobacco, like PVY^N-Wilga. Some PVY^N isolates caused tuber ring necrosis in glasshouse conditions. These might belong to the PVY^NTN group. The PVY^NTN, PVY^N-Wilga and PVY^Z groups probably represent pathotypes within strains PVY^N and PVY^O, respectively. The present study also confirms previous reports showing a high genetic variation at the 5 end within the PVYN strain.     

The autumn leafroller: Phenology,damage and parasitoids in a Dutch apple orchard

The phenology of the autumn leafroller,Syndemis musculana, a local pest of apple, was studied in order to forecast larval emergence. From 1983–1986, peak flight as determined with sexpheromone traps was always between 13–18 May. The duration of embryonic development was determined at various constant temperatures and used to estimate the periods of egg hatch in these four years. Each year, most eggs should have hatched in the second decade of June.Differences in attack rates between apple cultivars seem to be explained largely by the variation in picking time. Larvae are only half grown at the beginning of harvest (cv. James Grieve), and have gone into hibernation when the latest variety (cv. Golden Delicious) is picked. Moreover, the varieties Cox's Orange Pippin and Belle de Boskoop, picked about half time, are liable to receive additional damage by caterpillars brought with the picked fruits into storage.Various hymenopterous parasites were reared from caterpillars. As the only leafroller in the orchard which hibernates as mature larva,S. musculana may promote winter survival of some parasitoids, like the eulophidColpyclypeus florus.Samenvatting De fenologie van de herfstbladroller (Syndemis musculana Hübner), een incidentele plaag op appel, werd nader bepaald met het doel het uitkomen van de eieren te kunnen voorspellen. In 1983–1986 viel de piekvlucht, bepaald met behulp van feromoonvallen, steeds tussen 13 en 18 mei.De ontwikkelingsduur van de eieren bij verschillende constante temperaturen werd gebruikt om de periode van uitkomen te schatten. De meeste eieren zullen ieder jaar in de eerste helft van juni uitkomen.Geconstateerde verschillen in schade tussen appelrassen blijken goeddeels terug te voeren op verschillen in pluktijdstip. De rupsen van de herfstbladroller zijn pas half-was als de eerste appels eind augustus geplukt worden, terwijl tegen het einde van de oogst begin oktober de meeste al in winterslaap zijn. Met name tussentijdse rassen, als Cox's Orange Pippin and Schone van Boskoop, lopen extra schade op doordat grotere rupsen met de geplukte vruchten in de kist terecht komen.Uit de rupsen werden negen, al van andere boomgaardbladrollers bekende, sluipwespen gekweekt, Omdat deze bladrollersoort, als enige in de boomgaard, als volgroeide rups overwintert, lijkt zij bij uitstek geschikt als winterwaard.This study was carried out at the Experimental Orchard De Schuilenburg, Schuilenburg 3, 4041 BK Kesteren, the Netherlands, to which address correspondence should be addressed.     

The parasitoid complex ofLiriomyza cicerina on chickpea (Cicer arietinum)

Liriomyza cicerina (Diptera: Agromyzidae) is an important pest on chickpea in Turkey. The objective of this study was to determine the parasitoids and rates of parasitism ofL. cicerina on chickpea (Cicer arietinum L.) during the 2005 and 2006 seasons in ?anl?urfa province, Turkey. Leaves with mines were sampled weekly and kept in the laboratory to observe and count emerging leafminer and parasitoid adults. Eight parasitoid species were collected: the braconidsOpius monilicornis Fischer andOpius tersus Foerster and the eulophidsDiaulinopsis arenaria (Erdös) andNeochrysocharis formosa (Westwood), which occurred in both the winter and summer seasons;Diglyphus crassinervis Erdös,Neochrysocharis ambitiosa Hansson,Neochrysocharis sericea (Erdös) andPediobius metallicus (Nees), which occurred only in the summer growing areas.Diaulinopsis arenaria was the predominant parasitoid with 4–7.7% parasitism rate whileN. ambitiosa andO. monilicornis were the second and third most predominant species. The results of these trials show that sinceDia. arenaria occurred throughout every season, it could potentially be used for control of the leafminerL. cicerina.