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1.
Indiscriminate use of synthetic pesticides to control the pests causes negative effects on non-target organisms. Some of the chemicals under B and C categories are carcinogenic to humans. The present study was aimed to assess the antifeedant, larvicidal and pupicidal activities of Hygrophila schulii (syn. H. auriculata) and Blumea mollis against Helicoverpa armigera. Maximum antifeedant activity of 70.01% was observed in ethyl acetate extract of H. schulii at 5.0% concentration with LC50 value of 2.0%. B. mollis ethyl acetate extract at 5.0% concentration showed antifeedant activity of 35.40% with LC50 value of 8.38%. The data for antifeedant activity showed homogeneity of variances in Levene Statistics and normality in Shapiro–Wilk test. Ethyl acetate extract of H. schulii at 5.0% concentration showed 68.66% larvicidal activity with LC50 value of 2.97%. It also showed 73.33% pupicidal activity and was statistically significant from other treatments. No pupicidal activity was observed in ethyl acetate extract of B. mollis. All concentrations of ethyl acetate extract of H. schulii showed promising biological activities which differed statistically from other treatments. Ethyl acetate extract of H. schulii could be used to develop new botanical formulations to manage agricultural pests.  相似文献   

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Syrrhopodon gaudichaudii Mont. is lectotypified and its key features are discussed. A neotype is designated for Syrrhopodon hawaiicus Müll.Hal. and the taxon is placed in synonymy with S. gaudichaudii. A key to the species of Syrrhopodon occurring in the Hawaiian Islands is provided.  相似文献   

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The complexes [Cu(samen)Cu(L)] and [Cu(samen)Ni(L)2] (Lbpy, phen) have been synthesized by the reaction of sodium N,N′-ethylenedisalicylamidatocuprate(II) pentahydrate (Na2- [Cu(samen)]·5H2O), a divalent metal ion, and 2,2′- dipyridyl or 1,10-phenanthroline. Cryomagnetic data for the CuCu complexes did not fit the Bleaney- Bowers equation; but the data did fit a modified Bleaney-Bowers equation
with a large negative J and a significant negative θ, suggesting that a considerable magnetic interaction operates between essentially planar [Cu(samen)Cu(L)] molecules. The magnetisms of the CuNi complexes were well interpreted in terms of the susceptibility equation based on the Heisenberg model. An antiferromagnetic spin-exchange interaction (J= −13∼−14 cm−1) was suggested between the metal ions.  相似文献   

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Recent studies of early hominin body proportions paint a complex evolutionary picture, with multiple instances of reversal in body shape. These interpretations rest heavily upon the inferred limb joint proportions of Australopithecus africanus. For example, the partial skeleton Stw 431 has been suggested to show ape-like joint proportions compared to the A. afarensis specimen A.L. 288-1. This suggests an evolutionary reversal in the more recent A. africanus. However, no study has examined the probability of sampling the differences between Stw 431 and A.L. 288-1 from a single extant hominoid species. The present study compares elbow/hip and elbow/lumbosacral joint size ratios between Stw 431 and A.L. 288-1 using exact randomization, based on chimpanzee and human models of variation. Results indicate that differences in elbow/hip proportions between Stw 431 and A.L. 288-1 can be sampled from a single species. In contrast, differences in elbow/lumbosacral proportions between Stw 431 and A.L. 288-1 show a significantly low probability of being sampled from a single species. Thus, Stw 431 and A.L. 288-1 are not significantly different from each with regard to limb joint proportions, but Stw 431 has a significantly smaller lumbosacral joint. This pattern does not conform to previous interpretations of limb proportions in A. africanus. Low statistical power in the present study may account for the discrepancy. Further research is needed to illuminate the functional implications of variation in relative lumbosacral joint size in early hominins.  相似文献   

6.
Strongylocentrotus droebachiensis (O. F. Müller) and Strongylocentrotus pallidus (G. O. Sars) occur together over much of their ranges in both the Atlantic and Pacific Oceans and remain distinct species, but no strong barrier to genetic exchange has been found in a study in the San Juan Islands. Co-occurrence of embryos of both species in the plankton indicates similar times of spawning. Ova of S. droebachiensis are fertilized by sperm of S. pallidus but the reciprocal cross gives a percent fertilization near zero. Hybrids of both crosses are viable with pigmentation resembling S. pallidus in the larval stage and S. droebachiensis in the adult stage. Ova of first generation female hybrids are more readily fertilized by sperm of S. pallidus, so that gene flow through female hybrids is more likely to be from S. droebachiensis to S. pallidus than the reverse. Male hybrids were not tested. S. droebachiensis and S. pallidus from deeper waters have lower fecundity than shallow water S. droebachiensis, which suggests that in the deeper waters individuals are food limited. The hypothesis that S. pallidus uses the sterile male technique to reduce reproductive output of S. droebachiensis is considered and rejected.  相似文献   

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Melittis melissophyllum (Lamiaceae) is a perennial herb, typical of woody places, occurring in Italy with two subspecies, i.e., melissophyllum and albida. So far, the classification of these two taxa was only based on morphology, i.e., the presence of glandular trichomes, the dimension of the leaves, and the number of teeth on each side as the main discriminant characters. To find marker compounds to chemically discriminate the subsp. melissophyllum with respect to the subsp. albida, a solid-phase microextraction SPME analysis coupled with GC/FID (=flame ionization detector) and GC/MS was carried out. SPME proved to be a chemotaxonomically useful technique that permitted a clearly differentiation of the two subspecies at headspace level. The subsp. melissophyllum was characterized by high amount of the mushroom alcohol oct-1-en-3-ol and the phenolic coumarin, whilst the subsp. albida exhibited a high content in monoterpenes and sesquiterpenes, α-pinene, sabinene, and (E)-caryophyllene being the major compounds. Multivariate chemometric techniques, such as cluster analysis (CA) and principal-component analysis (PCA), were used to support chemical data and characterize the population according to the taxonomy. In addition, the micromorphology and distribution of glandular trichomes of both subspecies were studied by scanning electron microscopy (SEM).  相似文献   

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It remains unclear why there are only two vascular plant species in Antarctica, Deschampsia antarctica Desv. (Poaceae) and Colobanthus quitensis (Kunth) Bartl. (Caryophyllaceae). Despite progressing climate warming, there is also just one alien plant species found in the region, introduced by humans and spreading mainly in disturbed habitats. In the present article we try to interpret the data concerning the history of the biota and glaciations of the continent, proceeding from the assumption that both plants migrated to Antarctica during the Oligocene-Pliocene, when it was less isolated and the climate was more favorable for their naturalization. Genetic evidence was also taken into consideration. Our data allow suggesting secondary dispersal in the region, due to transfer by birds with regard of climate changes. With this in mind, we believe that D. antarctica and C. quitensis are migratory relicts.  相似文献   

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The title compound, I, crystallizes in the monoclinic space group P21 with cell constants: a = 6.599(3), b = 11.121(2), c = 8.375(1) Å and β = 106.35(2)°; V = 589.74 Å3 and D(calc; Z = 2) = 1.974 g cm−3. The compound is isomorphous and isostructural with its Co analogue. A total of 2982 data were collected over the range of 4°  20  70°; of these, 2537 (independent and with I ⩾ 3σ(I)) were used in the structural analysis. Data were corrected for absorption (μ = 16.6 cm−1) and the relative transmission coefficients ranged from 1.000 to 0.9504. Refinement was carried out for both enantiomeric configurations and the crystal used was found to contain cations with Δ(λδ) absolute configuration. The final R(F) and Rw(F) residuals were, respectively 0.0220 and 0.0239 for (−−−; i.e.Δ(λδ)) and 0.0231 AND 0.0317 FOR (+++; i.e.Λ(δλ)). Thus, the former was selected as correct for our specimen.In the case of I, as well as in the Co derivative [cis-Co(en)2(NO2)2]Cl (II), the conformation of one of the rings is opposite that expected for the lowest energy conformation, which in the current case should be Δ(λλ)).The RhN(NO)2 distances are 2.020(2) and 2.010(2) Å, while the RhN(amine) distances, trans to the NO2 ligands are 2.085(2) and 2.093(1) Å, values distinctly longer than the other two RhN distances (2.064(1) and 2.068(1) Å). The latter are the RhN distances to the terminalNH2 ligands located trans to each other. Thus, we observe a trans effect, which is more pronounced in I than in II, and which is of comparable magnitude to that observed in the case of the trien derivative, [cis-α-Rh(trien)(NO2)2]Cl(III).Parallel with an increase in metalN distances in going from [cis-α-Co(trien)NO2)2]Cl·H2) (IV) to (III) is an increase in the torsional angles of the outer rings (NCCN) of about 10°. Comparison of these parameters in I and II reveal that this change is not so marked for this pair since in I they are −54.9° and 52.8° while in II they are 50.2° and −48.1°; i.e. a change of only 4°. This important difference between trien and en derivatives is caused by the presence of the central five-membered ring, which for compounds III and IV remains largely unchanged, except for the metalN distances.The NO bond lengths are 1.244(3), 1.220)(2), 1.237(2) and 1.211(2) Å, which are similar to those found for the analogous Co isomer. The CN bond lengths are 1.492(3), 1.474(2), 1.486(2) and 1.475(2) Å, while the CC bonds are 1.509(3) and 1.524(3) Å. These values are also comparable with those obtained for the Co isomer and, in fact, the pattern of the bonds is nearly identical in both, including the common feature of having a longer CC bond for the en ring with the conformation opposite that expected.As was the case with the Co analogue, the Cl anion is associated with the hydrogens of the secondary nitrogen (trans to the −NO2) ligands, the Cl…H7 distance being 2.18(3) Å and the <Cl…H7N2 = 163°.  相似文献   

15.
Hybrid aspen (Populus tremula × P. tremuloides) belong to the section Populus. Eastern cottonwood (P. deltoides) is a member of the section Aigeiros within the genus Populus. These poplar sections are generally considered to be incompatible. Here, we describe successful hybridisation between these parents, producing an offspring family with 27 individuals. The hybrid character of individuals was proven by genotypes at 16 nuclear microsatellite loci. One individual was suspected to have more than the diploid chromosome number of 2n = 38 due to the observation of more than two alleles at several loci. This individual is a triploid, ascertained by flow cytometry. Two distinct growth classes of tall and dwarf plants were observed in the progeny, reflecting different degrees of postzygotic incompatibility. Two loci linked to the tested microsatellites have an effect on height growth. Some fast-growing individuals were micropropagated to test them for biomass performance together with other clones in field trials.  相似文献   

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The primary objective of this study was the isolation of low-density polyethylene (LDPE)-degrading microorganisms. Soil samples were obtained from an aged municipal landfill in Tehran, Iran, and enrichment culture procedures were performed using LDPE films and powder. Screening steps were conducted using linear paraffin, liquid ethylene oligomer, and LDPE powder as the sole source of carbon. Two landfill-source isolates, identified as Lysinibacillus xylanilyticus XDB9 (T) strain S7-10F and Aspergillus niger strain F1-16S, were selected as super strains. Photo-oxidation (25 days under ultraviolet [UV] irradiation) was used as a pretreatment of the LDPE samples without pro-oxidant additives. The PE biodegradation process was performed for 56 days in a liquid mineral medium using UV-irradiated pure LDPE films without pro-oxidant additives in the presence of the bacterial isolate, the fungal isolate, and the mixture of the two isolates. The process was monitored by measuring the fungal biomass, the bacterial growth, and the pH of the medium. During the process, the fungal biomass and the bacterial growth increased, and the pH of the medium decreased, which suggests the utilization of the preoxidized PE by the selected isolates as the sole source of carbon. Carbonyl and double bond indices exhibited the highest amount of decrement and increment, respectively, in the presence of the fungal isolate, and the lowest indices were obtained from the treatment of a mixture of both fungal and bacterial isolates. Fourier transform infrared (FT-IR), x-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses showed that the selected isolates modified and colonized preoxidized pure LDPE films without pro-oxidant additives.  相似文献   

18.
Fifty-eight strains, representing 31 species of Penicillium, were screened for extracellular -glycosidase (amygdalase/linamarase) and pectolytic (polygalacturonase, pectin lyase) enzymes. One strain each of P. turbatum, P. piceum and P. paxilli showed very high -glycosidase activity and slightly lower activities were found in P. crustosum, P. expansum, P. oxalicum and P. aurantiogriseum. Generally, maximum -glycosidase activity showed reached during the stationary phase of growth. The seven species with highest -glycosidase activity showed different patterns of pectolytic activities, indicating that different species or combinations of species could be selected for different potential applications.L. Brimer is with the Department of Pharmacology and Pathobiology, Royal Veterinary & Agricultural University, 13 Bulowsvej, DK 1870 Frederiksberg C, Denmark; A.R. Cicalini and F. Federici are with the Dipartimento Agrobiologia e Agrochimica, University of Tuscia, Via S.C. de Lellis, I-01100 Viterbo, Italy. M. Petruccioli is with the Dipartimento di Biologia, Difesa e Biotecnologie Agro-Forestali, University of Basilicata, Via N. Sauro, 85, I-85100 Potenza, Italy.  相似文献   

19.
Based on a further re-examination of loricate choanoflagellate species with detailed morphological (SEM/TEM) and molecular data of the SSU and LSU rRNA, the present study aims to give new insights for Stephanoeca cupula. In contrast to the original allocation within the family of tectiform reproducing species, morphological and molecular data of S. cupula sensu Leadbeater, 1972 points towards an affiliation within the nudiform reproducing family. Based on these new data, we here erect the nudiform genus Kalathoeca with its type species K. cupula gen. et comb. nov. Our data challenges morphological species assignments, as K. cupula shares its morphological lorica characteristics with tectiform reproducing species of Stephanoeca sensu stricto. Kalathoeca cupula is an interesting candidate for further investigating and understanding the evolutionary relationship of tectiform and nudiform reproducing species.Stephanoeca cupula sensu Thomsen, 1988 has been morphologically re-examined based on the renewed understanding of the morphological variability associated with S. cupula sensu Leadbeater, 1972 (=K. cupula), allowing us now to distribute the different morphological forms investigated within K. cupula and Pseudostephanoeca quasicupula.  相似文献   

20.
The morphology and infraciliature of two hypotrichous ciliates, Urosoma salmastra and U. karinae sinense nov. sspec., were investigated for populations collected from the surface of intertidal gravel in the Huguang Mangrove Forest, Zhanjiang, China and the upper 10 cm layer of soil in the Sangke Grass Land in the southern part of Gansu Province, China, respectively. Urosoma salmastra is characterized by its elongate-elliptical body with no tail-like structure; two macronuclear nodules; cortical granules colourless, less than 1 μm across, and arranged in short rows; adoral zone occupying 25% of body length in vivo; paroral conspicuously short and located in front of endoral. Urosoma karinae sinense nov. sspec. is characterized by its elongate-elliptical body with no tail; 2–4 macronuclear nodules; cortical granules colourless, less than 1 μm across, and arranged in short rows; adoral zone occupying 30% of body length in vivo; paroral shorter than, and located ahead of endoral. Phylogenetic analyses based on SSU rRNA gene sequence data suggest a close relationship between U. salmastra, U. karinae sinense nov. sspec. and Oxytricha granulifera within the Oxytrichinae assemblage.  相似文献   

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