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1.
Urediniospores ofCronartium ribicola J. C. Fisch. exRabenh. were observed within the petiole ofRibes petiolare L. These spores occurred internal to xylem tissues within the region of undifferentiated parenchyma cells (pith). Fungal tissues were sparse and fully differentiated sori were absent.Research Plant Pathologist and Biological Laboratory Technician, USDA Forest Serv., Intermountain Forest and Range Exp. Sta., Ogden, Utah, stationed in Moscow, Idaho83843, at Forestry Sciences Laboratory, maintained in cooperation with the University of Idaho.  相似文献   

2.
An efficient protocol for Kentucky bluegrass (Poa pratensis L.) in vitro culture was established using shoot apices of seedlings as explants. The optimal procedure of this protocol for majority of the genotypes was that meristematic cell clumps and small calluses were firstly induced from the bases of explants on initial culture medium supplemented with 0.9 μM 2,4-d and 8.9 μM 6-BA for 20 d, then were separated and transferred to shoot clumps induction medium containing 8.9 μM 6-BA for the formation of multiple shoot clumps. The percentage of multiple shoot clumps and numbers of shoots per clump were deeply related with the combinations of different plant growth regulators, duration of initial culture, the intensity of illumination and genotypes. Histological observation of the induced explants revealed that the meristematic cell clumps were produced from repeated division of the cortical cells and original meristematic primodium cells of explants, and the multiple shoots were formed via organogenesis pathway in the meristematic cell regions of cultures on shoot clumps induction medium. In this study, plantlets were efficiently regenerated on large scale from seven cultivars of Kentucky bluegrass. Hence the meristematic cell clumps and small calluses in this protocol could be considered good targets for genetic transformation of Kentucky bluegrass.  相似文献   

3.
Summary A new species ofSaccharomyces is described, which was isolated from soils. The nameSaccharomyces smittii is proposed in memory of the late Prof.Jan Smit (Director of the Laboratory for Microbiology, Wageningen, Holland).  相似文献   

4.
Summary A list of 24 species of lépidoptères is presented, showing the comparative sensibility towardsBacillus thuringiensis b. Theses species have been approved only in preliminary tests in the Laboratory of La Minière. Therefore, the results have an indicative and provisional character. The list completes an important documentation gathered bySteinhaus in a polycopied recollection, that has been transmitted to specialists in 1957.   相似文献   

5.
Summary A new species of Torulopsis is described; it was isolated from some materials used for silage. This species is named Torulopsis wickerhamii nova species in honour of Prof. L. J. Wickerham of Northern Regional Research Laboratory at Peoria-Illinois-U.S.A.  相似文献   

6.
The CerambycidAlcidion cereicola Fisher attacks cacti in northern Argentina, the larval feeding resulting in the death of mature plants. The insect is hardy and easily reared, with a short life cycle. Laboratory tests and field observations demonstrate that it will only damage plants in the sub-familyCereanae of theCactaceae. It was approved for liberation in Queensland, Australia, in October 1974 for the control ofEriocereus martinii Lab.
Résumé Le longicorneA. cereicola Fisher ataque les Cactus d'Argentine septentrionale, les larves provoquant la mort des plantes adultes. L'insecte est robuste et facile à élever, ayant un cycle biologique de courte durée. Les observations faites en laboratoire et dans la nature montrent qu'il s'attaque exclusivement aux plantes de la sous-familleCereanae de la famille des Cactacées. Son introduction en Queensland, Australie a été approuvée en Octobre 1974 pour la lutte contreEriocereus martinii Lab.


FormerlyCruttwell.  相似文献   

7.
Summary An investigation of the zoosporic fungi in the vicinity of the Friday Harbor Laboratory, San Juan Is., Washington, revealed the presence of great numbers of fungi. With one exception (Olpidium sp.) these were all biflagellate organisms. Predominating were species (11) of Thraustochytriaceae which abounded in water, in association with seaweeds, intertidal sands, and particularly on the surface of bottom samples down to depths of 298 m. A twelfth species of this group has several peculiarities and needs further investigation. Of the algal parasites, one on Polysiphonia and Pterosiphonia is considered new and termed Eurychasma joycei n. sp.The assistance of Drs. R. E. Norris and G. J. Hollenberg in calling my attention to certain algal parasites is gratefully acknowledged. I am also indebted to my colleague Dr. H. C. Whisler, and to Dr. C. Anastasiou for assistance in photographic work.  相似文献   

8.
During observations in soybean fields, 136Neoscona arabesca (Walckenaer) and 46Tetragnatha laboriosa Hentz were collected with prey. Significantly different prey compositions were recorded, withN. arabesca utilizing a large number ofColeoptera whileT. laboriosa captured primarilyHemiptera-Homoptera. Neoscona arabesca was observed to feed primarily in the evening following web construction, whileT. laboriosa fed predominantly in the morning. Although both of these species captured relatively large numbers of homopterans, most of their prey were species which are not considered to be pests in soybean.
Résumé Lors d'observations dans des champs de soja, 136Neoscona arabesca (Walckenauer) et 46Tetragnatha laboriosa Hentz furent recueillies avec leurs proies. Des différences significatives furent notées dans la composition des différents groupes de proies,N. arabesca capturant un grand nombre de Coléoptères tandis queT. laboriosa capture en premier lieu des Hémiptères (Hemiptera-Homoptera). Il fut observé queNeoscona arabesca se nourrit surtout dans la soirée qui suit la construction de la toile, alors queT. laboriosa se nourrit le plus souvent le matin. Bien que ces deux espèces aient capturé un nombre relativement important d'homoptères, la plupart de leurs proies étaient des espèces qui ne sont pas considérées comme nuisibles au soja.


This paper (82-7-20) is in connection with a project of the Kentucky Agricultural Experiment Station and is published with the approval of the Director.  相似文献   

9.
Patasson lameerei Debauche development from egg to adult emergence onSitona hispidulus (Fabricius) eggs at 7.2, 10.0, 15.6, 21.1 and 26.7°C required 154.1, 75.4, 24.3, 17.6, and 12.9 days for females and 147.3, 61.0, 23.4, 15.4, and 11.6 for males, respectively. At 21.1°C the optimal age ofS. hispidulus eggs for parasitism byP. lameerei was 2 days, with effective parasitism occurring on eggs ranging from 1 to 4 days old.
Résumé Le développement dePatasson lameerei Debauche de l'œuf à l'émergence de l'adulte sur des œufs deSitona hispidulus (F.) à 7,2, 10,0, 15,6, 21,1 et 26,7°C a nécessité 154,1, 75,4, 24,3, 17,6 et 12,9 j pour les femelles et 147,3, 61,0, 23,4, 15,4 et 11,6 j pour les males, respectivement. A 21,1°C, l'age optimal des œufs deS. hispidulus pour le parasitisme deP. lameerei a été de 2 j, un parasitisme effectif ayant lieu sur des œufs agés de 1 à 4 j.


This paper is published with the approval of the Director of the Kentucky Agricultural Experiment Station as Journal Article No 79-7-33.  相似文献   

10.
Nostoc cycadae isolated from the host Cycas revoluta grew well in medium devoid of combined nitrogen but maximum growth was in medium containing nitrate (4.1 g chlorophyll a ml-1). Aerated coralloid roots in the dark produced more NH3 when treated with l-methionine-dl-sulphoximine (MSO), an inhibitor of glutamine synthetase. With cultured N. cycadae and freshly isolated N. cycadae, NH3 production was enhanced by adding a host-tissue extract in the light or in the dark, whereas it was decreased by adding MSO. Nitrogenase activity was four times higher in coralloid root than in the cultured endophyte N. cycadae. The host-tissue extract may inhibit NH3 assimilatory pathways, thus inducing production of NH3 that can be utilized by the host itself.V. Singh, M.R. Goyle and E.R.S. Talpasayi are with the Laboratory of Algal Physiology and Biochemistry and A.K. Srivastava is with the Ecology Research Laboratory, both of the Centre of Advanced Study in Botany, Banaras Hindu University, Varanasi-221005, India.  相似文献   

11.
Summary A morphological analysis of the initiation and development of root nodules ofElaeagnus angustifolia andMyrica cerifera inoculated with pure-culturedFrankia strains DDB 011610 or DDB 020110 was undertaken. From ultrastructural observations it was determined that both of theseFrankia strains can infectElaeagnus by an intercellular penetration mechanism andMyrica by the root hair infection mechanism. This indicates that both of these strains have the ability to infect host plant roots by either of two mechanisms. The reverse, thatElaeagnus orMyrica could be infected by both mechanisms, was not observed. The infection and nodule development processes of these two plants in combination with these strains were similar to observations made in previous studies (Miller andBaker 1985,Torrey andCallaham 1979). However, one exception was identified in the development of the prenodule ofMyrica when infected with strain 011610, in that endophytic hyphae developed vesicles within the cells of the prenodule. This event has not been described before for any of the actinorhizal genera and may be an indication of less than optimal compatibility between the host plant and the symbiont.Contribution no. 876 of the Battelle-Kettering Laboratory.  相似文献   

12.
The chromosome complement of Gueriniella serratulae (F.) Fernald, Tribe Iceryini, Subfamily Monophlebinae of the primitive coccid Family Margarodidae, is 2 n =6; males are unknown. Reproduction is by thelytokous parthenogenesis. Meiosis is normal; polar bodies do not contribute to the formation of a zygote-substitute nucleus; and development is initiated by a haploid cleavage of the female pronucleus. Diploidy is restored by the fusion of the 2 nuclei resulting from this division. With the exception of Gueriniella, all cytologically known Iceryini are haplo-diploids, with a chromosome complement of n=2. The hypothesis is proposed that Gueriniella is a persistent primitive stemming from the ancestral iceryine stock prior to the loss of the sex chromosomes and the evolution of haplo-diploidy within the tribe. A review of the available evidence from cytology, taxonomy, endosymbiosis, behavior and distribution shows good agreement with this interpretation.Dedicated to Professor Jakob Seiler on the occasion of his 80th birthday.Supported in part by National Science Foundation Grant GB-1922 to S. Hughes-Schrader; we also gratefully acknowledge the support of Professor G. Russo, Director of the Entomological Laboratory, Portici.  相似文献   

13.
In the light, 2 out of the 4 newly testedChlorella vulgaris strains were found to use about as many amino acids as a source of nitrogen as the previously investigated strain Delft; the other 2C. vulgaris strains and 3 of theAnkistrodesmus strains used only a few. The 4thAnkistrodesmus strain used none.On the average,l-amino acids supported better growth thand-amino acids, butd-serine was preferred tol-serine by 3Ankistrodesmus strains.In the dark, growth was only obtained withC. vulgaris strain Delft, and only on a few of thel-amino acids,l-leucine in particular.The author is indebted to the Direction of the Academic Hospital Dijkzigt, Rotterdam and to Prof. Dr. H. Esseveld, Head of the Central Bacteriological Laboratory, Rotterdam, for providing facilities for the performance of this study.He thanks Mrs. Dr. H. J. Leijnse-Ybema for her help in making the chromatograms, and Mr. J. B. Lenstra, pharmacist, for advice in matters of organic chemistry.  相似文献   

14.
Vegetative mycelia ofCronartium ribicola J. C. Fisch. exRabenh. that were removed from media surrounding infected pine host tissue cultures did not survive when transplanted to a defined artificial medium. Similar mycelia retained on a medium that had formerly supported pine host tissue cultures did survive for periods up to 120 days. These mycelia were fully capable of reinfecting healthy host tissue cultures.
Zusammenfassung Vegetative Myzelien vonCronartium ribicola J. C. Fisch. exRabenh., die von Nährmedien, die die Gewebskultur des infizierten Kiefernwirtes umgeben, entfernt worden sind, überlebten nicht, wenn sie auf einen definierten, künstlichen Nährboden übertragen worden sind. Ähnliche Myzelien auf einem Nährboden gehalten, der vorher Kiefer-Gewebskultur getragen hat, überlebten für eine Periode bis zu 120 Tagen. Diese Myzelien waren fähig, gesunde Wirtsgewebekulturen wiederum zu infizieren.


stationed in Moscow, Idaho, at Forestry Sciences Laboratory, maintained in cooperation with the University of Idaho.  相似文献   

15.
The weevilEriocereophaga humeridens O'Brien attacks the cactusEriocereus adscendens (Gurke) in N.E. Brazil. Laboratory tests and field observations demonstrate that it will also acceptEriocereus martinii Lab. as host, and does not damage plants except in the sub-familyCereanae of theCactaceae. Young plants and regrowth are preferentially attacked and larval feeding inE. martinii results in the death of attacked stems.E. humeridens was approved for liberation in Queensland, Australia in February 1976, for the control ofEriocereus spp., and field releases were made in 1976.
Résumé Le coléoptèreEriocereophaga humeridens O'Brien attaque le cactusEriocereus adscendens (Gurke) qui est indigène du Nord-Est du Brésil. Il a été établi par des essais en laboratoire ainsi que par des observations en champ d'expérimentation, qu'E. humeridens peut également vivre surEriocereus martinii Lab., et qu'il n'est nuisible que pour les plantes de la sous-familleCereanae desCactaceae. Il attaque de préférence les jeunes pousses et les rejetons; et ses larves tuent en les mangeant les tiges d'E. martinii qui sont atteintes. En février 1976, afin de limiter les espèces d'Eriocereus, l'approbation fut donnée de lacherE. humeridens en Queensland, Australie, ce qu'on a fait sur les lieux au cours de la même année.
  相似文献   

16.
R. E. McFadyen 《BioControl》1979,24(3):281-287
The mealybugHypogeococcus festerianus (Lizer y Trelles) infests cacti in Northern Argentina and Paraguay, causing deformed and distorted growth of attacked plants. Laboratory studies and field observations demonstrate that it will only infest plants in the sub-familyCereanae of theCactaceae. Its liberation in Queensland, Australia, for the control ofEriocereus spp., was approved in October 1974, and it has since established widely.
Résumé La cochenille farineuseHypogeococcus festerianus (Lizer y Trelles) infeste les cactus dans le nord de l’Argentine et le Paraguay, causant chez ces plantes, des déformations et une croissance anormale. Les observations faites dans la nature et en laboratoire montrent qu’elle s’attaque exclusivement aux plantes de la sous-famille desCereanae de la famille desCactaceae. Son introduction en Australie a été approuvée en octobre 1974, et elle s’est largement établie depuis.
  相似文献   

17.
The searching strategies ofOrius insidiosus (Say) exposed to various densities of the soybean thrips,Sericothrips variabilis (Beach), were observed on soybean trifoliolates under laboratory conditions. The effects of prey density on the predator's searching speed and feeding time were evaluated. Predator searching speed and feeding time per soybean thrips declined with increases in prey density. The greatest number of predator-prey encounters occurred on the upper midrib of the soybean trifoliolate. Adult soybean thrips were captured in 45 and 56% of their total encounters with adult male and femaleO. insidiosus, respectively. Running was found to be the primary escape tactic used by soybean thrips in response to attack byO. insidiosus.
Résumé Les stratégies de recherche deOrius insidiosus (Say) exposé à des densités variées de thrips du soja,Sericothrips variabilis (Beach), furent observées sur du soja à 3 folioles en laboratoire. Les effets de la densité de la proie sur la vitesse de recherche et sur le temps nécessaire au prédateur pour se nourrir furent évalués. La vitesse de recherche et le temps de nourriture du prédateur sur le thrips du soja déclinèrent avec l'accroissement de la densité de la proie. Les rencontres prédateur-proie eurent lieu dans leur majorité dans la partie supérieure de la nervure du soja. Les thrips du soja adultes furent capturés respectivement dans 45 et 65% du total de leurs rencontres avec des males et des femelles adultesO. insidiosus. Courir s'est avéré être la tactique primaire de fuite utilisée par les thrips de soja en réponse aux attaques deO. insidiosus.


This paper (No. 80-7-204) is in connection with a project of the Kentucky Agricultural Experiment Station and is published with the approval of the Director.  相似文献   

18.
肯塔基沙门菌是引发人类和畜禽肠道疾病的重要人兽共患病原菌之一,普遍具备多重耐药性.近年来,肯塔基沙门菌在全球流行趋势逐渐上升,严重威胁畜禽健康和公共卫生安全.本文综述了国内外肯塔基沙门菌的流行状况、耐药性及防控措施研究进展,以期为肯塔基沙门菌病的防控提供参考和思路.  相似文献   

19.
l-Glycerol 3-phosphate dehydrogenase (E.C. 1.1.1.8) was purified from the muscle of BALB/cJ and C57BL/6J mice. The half-lives of the enzyme at 50 C were 6 and 33 min, respectively, for the BALB/cJ and C57BL/6J strains. Enzyme preparations from the two strains of mice were compared with respect to the following properties and found to be essentially indistinguishable: K m values for dihydroxyacetone phosphate, NADH, l--glycerophosphate, and NAD+; maximum velocity; competitive inhibition by inorganic phosphate; pH optimum; energy of activation; electrophoretic mobility; molecular weight and subunit molecular weight. From these data, it is concluded that the kinetic properties of the purified enzyme are not the factors responsible for the differences in activity found in crude homogenates of mouse tissues.This work was supported by NIH Research Grant HD 06712 from the National Institute of Child Health and Human Development and by an allocation from NIH General Research Support Grant RR-05545 from the Division of Research Resources to The Jackson Laboratory. The Jackson Laboratory is fully accredited by the American Association for Accreditation of Laboratory Animal Care.  相似文献   

20.
Individual variations of 1-antitrypsin of the macaques were investigated by means of starch gel electrophoresis. The material comprised a total of 1,084 plasma samples taken from six species, namely,Macaca irus, mulatta, cyclopis, nemestrina, speciosa, andfuscata, including several geographical groups. At least ten phenotypes which were assumed in analogy to human Pi-system to be under genetic control of five codominant alleles tentatively denoted byPi Mac A, B, C, D, E were identified. It was considered that these alleles are commonly possessed by different macaque species. A marked difference in the distribution of allele frequencies was found both within and between species groups. Several aspects of this new polymorphic variation in the macaques were discussed with special reference to the geographical distribution of the alleles and the origins of the Japanese macaque,M. fuscata. This study was carried out as part of the Special Project of the Japan-U.S. Cooperative Scientific Program: Blood Macromolecules and the Genetic Origins of the Japanese Macaques (Chief investigators:T. Miki andM. Goodman)  相似文献   

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