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1.
2.
The pattern of virulence (based on inclusion bodies) for 3 baculoviruses ofHeliothis, i.e. a unicapsid, nuclear polyhedrosis virus (HzSNPV); a multicapsid, nuclear polyhedrosis virus (HaMNPV); and a granulosis virus (HaGIV) was the same (HzSNPV>HaMNPV>HaGIV) for 3 species ofHeliothis. Based on numbers of nucleocapsids, however, the HaGIV was ca 2X more virulent than the HaMNPV for larvae ofH. virescens, (F.), and the HaMNPV was about 6X more virulent than the HaGIV for larvae ofH. armigera (Hübner). The fastest rate of larval mortality was obtained with HzSNPV. Although the mortality rate for HaGIV was faster than that of HaMNPV forH. virescens andH. armigera, it was slower than that of HaMNPV for larvae ofH. zea (Boddie). The pattern of susceptibility ofHeliothis species to HzSNPV and HaMNPV wasH. zea>H. virescens>H. armigera. Differences in susceptibility of the least susceptible species (H. armigera) and the most susceptible species (H. zea) to HzSNPV was ca. 1.6 X. Larvae ofH. zea, however, were ca. 4 to 6 X more susceptible to HaMNPV than were larvae ofH. virescens orH. armigera. A different pattern of susceptibility was recorded for HaGIV when larvae were challenged with HzSNPV and HaMNPV. Larvae ofH. virescens were ca. 20 and 35 X more susceptible to HaGIV than were larvae ofH. zea andH. armigera, respectively.  相似文献   

3.
A comparison of some genera of the Condaminecae (Rubiaceae) with a few taxa of closely related tribes (Rondeletieae, Calycophylleae, and Cinchoneae) revealed that some species ofChimarrhis (Condamineeae s. 1.),Bathysa (Rondeletieae), andCalycophyllum (Calycophylleae) are often misassigned to genera. The taxonomic significance of calycophylls is discussed; the generic boundaries ofChimarrhis, Bathysa, andCalycophyllum are reevaluated; and their similarities and differences are discussed. As a result, a new calycophyllous species ofChimarrhis from the Amazon,C. gentryana, is described, two of its species are transferred toBathysa (B. Bathysoides, B. perijaënsis), and one species ofBathysa (B. difformis) is reduced to synonymy underChimarrhis (C. turbinata).  相似文献   

4.
A. J. Wapshere 《BioControl》1982,27(2):173-181
Two halticine flea beetles,Longitarsus echii Koch andLongitarsus aeneus Kutsch, occurring on the boraginaceous plantEchium plantagineum L. in the western Mediterranean region are potential biological control agents in Australia where the plant has become a weed (Paterson's curse). The adults of both species feed by making “shot holes” in the leaves. The larvae of both species attack the roots ofEchium, those ofL. echii feeding more centrally in the root than those ofL. aeneus which attack the outer cortex and rootlets. Both species are univoltine. The host restrictions of both flea beetles as adults and as larvae were tested using the criteria already established for theEchium leaf minerDialectica scalariella Zeller (Wapshere & Kirk, 1977). This testing established that it would be safe to introduce the 2 insects into Australia for the biological control ofE. plantagineum and they are now under quarantine.  相似文献   

5.
Morphological, isozyme, and cytological analyses of the small, pale-scaled polystichums from oakdominated montane rain forests in Costa Rica and Mexico reveal the presence of a separable undescribed species endemic to the Cordillera de Talamanca of Costa Rica. The new taxon,Polystichum lilianae, is an allotetraploid hypothesized to have the sympatricP. turrialbae as one diploid progenitor based on isozyme characters. The isozyme and morphometric data also support the inclusion ofP. smithii, described from southern Mexico, inP. turrialbae, described from Costa Rica. The namePolystichum fournieri, formerly used for all of these plants, applies to species endemic to Oaxaca and Chiapas, Mexico. It is not a progenitor ofP. lilianae.  相似文献   

6.
Bergisuchus dietrichbergi Kuhn is redescribed as a member of its own family, Bergisuchidae n. fam., within the Sebecosuchia. At present, two fragmentary specimens ofBergisuchus are known: the holotype ofBergisuchus, a partial rostrum, comes from the lower part of the Middle Eocene of the Messel pit, near Darmstadt; and a recently discovered fragmentary mandible from the middle part of the Middle Eocene of Geiseltal in an opencast coal-mining pit near Halle (Saale).Bergisuchus shows similarities with species ofSebecus which are known from the Paleocene to Miocene from South America. All palaeoecological and biomechanical data support the hypothesis ofBergisuchus as a small, mainly terrestrial crocodile, which did not build its nests near either of the fossil localities from which it has been collected.  相似文献   

7.
The width of the increment zones in the xylem of Swietenia macrophylla King and Cedrela odorata L. was investigated by dendroecological methods in a primary forest near Aripuanã, Mato Grosso, Brazil (10°09′S, 59°26′W). The annual period of cambial cell division and its intra-annual variation were determined by dendrometer measurements of 30 trees of each species. Tree-ring width chronologies for Swietenia and Cedrela were developed from cross-dated increment curves of 33 out of 47 Swietenia and 51 out of 64 Cedrela trees. Simple correlations were computed between the radial growth increment and monthly precipitation for the period 1890–2000. In Swietenia, cambium activity occurred throughout almost the whole year, but in Cedrela it was restricted to the rainy period from September of the previous year to June of the current year. Tree-rings were formed annually in the juvenile and adult wood of Cedrela, while in Swietenia the annual formation of tree-rings was restricted to the adult wood. Consequently the age of the Swietenia trees could be dated by the tree-rings in good approximation, while age dating of the Cedrela trees was exact. Correlation analyses revealed a significant relationship between the precipitation at the beginning and at the end of the growth season and the width of the increment zones in the adult xylem of Swietenia. In contrast, the width of the growth increment in the xylem of Cedrela was significantly correlated with the precipitation in March and May of the previous growth period.  相似文献   

8.
Fifteen species of Heterostropha are described, 12 of them for the first time. All are newly interpreted with regard to their taxonomic relation to fossil and living gastropods. The Streptacidoidea with long Paleozoic history are represented in the Late Triassic St. Cassian Formation by several genera that can be differentiated into four families. The Ebalidae are represented byEbala, with smooth protoconch, Cassianebalidae byCassianebala andLoxebala with axially ornamented protoconch. The Donaldinidae of St. Cassian are represented by one species ofDonaldina and two ofNeodonaldina that stand in the continuation of Paleozoic species ofDonaldina. Architectonicoidea with shells coiled in a plane and Valvatoidea appear in the St. Cassian fauna without known Paleozoic relation. In the former superfamily the Architectonicidae can be recognized in the genusRinaldoconchus with two species. Cassianaxidae withCassianaxis, Amphitomariidae withAmphitomaria, Stuoraxidae withStuoraxis andAmpezzogyra have a sinistral protoconch and planispirally coiled dextral teleconchs. They all resemble different modern species that have similarly small shells. Modern Hyalogyrinidae have withAlexogyra a new representative from the Triassic. The Valvatoidea are represented with the generaCarboninia andBandellina of the Cornirostridae in the Triassic representatives. The relation of described species in the system of the Heterostropha is discussed.  相似文献   

9.
Scymnodalatias albicauda sp. nov. is described from two specimens taken at high latitudes (45°S and 49°S). It is distinguished fromS. sherwoodi, only known species of the genus, by having white markings on the caudal fin, the second dorsal posterior tip almost reaching the upper caudal fin, shorter snout and head, smaller eye and larger fins. Relationships ofScymnodalatias to the generaScymnodon, Centroscymnus, andZameus are discussed, based chiefly on dermal denticle structure.Scymnodalatias andZameus uniquely share transverse ridges on their dermal denticles, and on this character they are treated as sister-groups. Comments on the above genera,Z. squamulosus and some species ofScymnodon are made to clarify their systematic status. As a result, it is proposed thatScymnodon includesichiharai, macracanthus, plunketi, andringens, thatCentroscymnus includescoelolepis, crepidater, crypt acanthus, andowstonii, and thatZameus includessquamulosus.  相似文献   

10.
A study of herbarium material ofLepanthes indicates that there are at least 18 species on Cuba. The history of the collections and publications on the genus from the island is summarized, and a detailed key to the species is given. One new combination is proposed (L. blepharophylla) and the following species are described as new:L. acunae,L. dressleri,L. cubensis,L. grisebachiana,L. obliquiloba, andL. occidentalis, of which three are from western provinces and two have been associated with inappropriate names.L. mandibularis Reichb. f. is tentatively considered a synonym ofL. chrysostigma Lindl. although the type ofL. mandibularis could not be found. The range of variation included under the nameL. fulva Lindl. suggests that more than one species is involved.  相似文献   

11.
The polyphyly ofSarcostemma sensu latu, suspected on morphological and karyological reasons is confirmed by analysis of thetrnL-F spacer region. With the exception ofCynanchum montevidense (subgen.Mellichampia, Sundell 1981), Old World and New World taxa belong to different clades.Sarcostemma sensu stricto andPlatykeleba show a strong affinity to Old WorldCynanchum; the affinities ofOxystelma cannot be determined at present.Philibertia andBlepharodon are sister groups, both are sister toFunastrum, andPentacyphus is basal to the New World clade.  相似文献   

12.
The effect of pyrimidine-enriched medium on the expression of the sex-linked female sterile mutationsrudimentary (r) andsonless (snl) ofDrosophila melanogaster was investigated. Although pyrimidine supplementation did significantly improve the fertility ofr females, as others have previously reported, it had no effect onsnl females. The total ribonucleic acid (RNA) content of eggs produced byr, snl, and control females was also measured. Eggs produced from homozygousr females mated tor males contained less total RNA than did eggs from other matings. These results support the hypothesis that certain sex-linked female sterile mutations cause the production of eggs deficient in some respect. In the case ofr, the deficiency seems to by pyrimidines. The biochemical deficiency associated withsnl requires further investigation.  相似文献   

13.
O. Bakkendorf 《BioControl》1971,16(4):363-366
Oligosita tominici n. sp. is described, bred fromErythroneura eburnea (Cicadellidae) and a key to theminima-group is given.Anagrus atomus (L.) is recorded fromErythroneura eburnea, too, andAnaphes autumnalis Foerster is bred from an egg ofTipula autumnalis Loew; it is the first record of an egg-parasite ofTipulidae.  相似文献   

14.
C. Stenseth 《BioControl》1979,24(3):311-317
The development ofPhytoseiulus persimilis Athias-Henriot and the effectiveness of it as a predator ofTetranychus urticae (Koch) were studied at constant temperatures of 15°, 18°, 21°, 24° and 27°C (humidity fluctuations from 60% to 90% R.H.) and at constant humidities of 40% and 80% R.H. at the temperatures 21° and 27°. Optimal temperature for time of development was 27° (at 60%–85% R.H.). A high reduction in egg vitality was recorded at 40% R. H. and 27% At 21° the egg vitality was only slightly lower at 40% R.H. than at 80% R.H. The predator gave control ofT. urticae at temperatures from 15° to 27° (humidity fluctuation from 60%–90% R.H.), and the most rapid and efficient control was obtained at 27° (60%–85% R.H.). The predator did not give sufficient control ofT. urticae at 27° and 40% R.H. At 21° control ofT. urticae was obtained at both 40% and 80% R.H., but the prey population was reduced faster at 80% R.H. than at 40% R.H.  相似文献   

15.
In a population of cells labeled with a single injection of tritiated thymidine at timet=0, it is assumed that a constant fraction, 1?z, of the cells which are potentially able to divide fail to do so, and that the cells which do divide all have identical generation time,D. Death and emigration of cells are neglected. In mitosis, the partitioning of label among the two daughter cells is supposed to follow the binomial probability law. Using the formalism developed by H. Von Foerster the fraction of labeled cells in the total population is computed as a function oft, the time after injection of label. Ift is an integral multiple ofD the results coincide with those of S. A. Tyler and R. Baserga.  相似文献   

16.
17.
Palaeosaurus (?) diagnosticus Huene from the Stubensandstone (Upper Triassic, Norian) of Nordwürttemberg, Germany is made the type species of a new genus of prosauropod dinosaurEfraasia, which is referred to the family Anchisauridae. The anatomy ofEfraasia diagnostica is conservative and it was an ideal ancestor for the later and more specializedAnchisaurus polyzelus of North America. The slenderness of the manus and pes ofEfraasia andAnchisaurus is matched amongst prosauropods only by the feet ofGyposaurus capensis andThecodontosaurus antiquus. Staurikosaurus pricei Colbert from the Upper Triassic of Brazil is probably a very primitive theropod dinosaur.  相似文献   

18.
A simple method of extracting the eggs ofSitona spp. from the soil is described. From 1973 to 1975 it was used in Spain, France, Italy and Greece to collect in good condition the eggs ofSitona humeralis Stephens, a weevil which has recently become a major pest in Australia. A mymarid parasitoid provisionally identified asPatasson lameerei Debauche emerged from these eggs apparently unaffected by the extraction method.  相似文献   

19.
Larval development ofOdontobutis obscura obscura, reared withArtemia sp. andLimnodrilus sp. for about two months, was observed in a room maintained at 20±0.5°C. The development was classified into nine nominal stages, and was compared with that ofO. o. interrupta and ofO. platycephala. The size and shape of the eggs and the development of this species are similar to those ofO. o. interrupta andO. platycephala. From the juvenile stage,O. obscura is distinguishable fromO. platycephala by the appearance of dark bands on the body located in the same position as in adults.O. o. interrupta is also distinguished fromO. o. obscura in the juvenile stage by the presence of melanophores on the dorsal and ventral sides of the caudal peduncle. The anal fin fold ofO. obscura is higher than the dorsal fin fold, but the two folds are equal in height inO. platycephala. O. obscura has a well-developed air bladder and swims high in the water at the feeding stage.O. platycephala has a poorly developed air bladder and swims on the bottom. Xanthophores are observed at an earlier stage and more strongly developed inO. obscura than inO. platycephala. Growth rate is faster inO. obscura than inO. platycephala. O. obscura spawns at a smaller body size thanO. platycephala. InO. o. obscura, the arrangement of cephalic pit organs is completed at 14 mm SL. InO. o. interrupta, this arrangement is completed at the same time or a little later than inO. o. obscura. The infraorbital and verticalantorbital pit lines ofO. platycephala, which are separated in the adults, are connected until the juveniles measure about 30 mm SL. These pit lines are connected even in the adults ofO. o. obscura andinterrupta. InO. platycephala, the sensory canals are first formed behind the eyes, then dorso-anterior to the eyes, then at the posterior edge of the preopercles and finally anterior to the eyes. Postocular canals begin to form in individuals more than 20 mm SL. All individuals ofO. o. interrupta more than 70 mm SL have postocular canals.O. o. obscura has no sensory canals throughout life. The differences in growth rate, body size at spawning, and the time of completion of the cephalic lateral line system suggest paedomorphosis in the three taxa studied here.  相似文献   

20.
Puccinia tatrensis Urban onGeum reptans in Czechoslovakia is recognized as a subspecies ofPuccinia sieversiae Arth.Puccinia waldsteiniae, P. gei andP. gei-parviflori appear to be the most ancient rusts known on the tribeGeeae and it is assumed that their common ancestral form was already present in the Cretaceous period.Puccinia sieversiae is more advanced and has its centre of origin and spread in Central Asia. Phylogenetically most advanced and at the same time most differentiated from each other are species ofPhragmidium, i.e.P. circumvallatum andP. miyabeanum.  相似文献   

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