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101.
The European spruce bark beetle, Dendroctonus micans Kugelann (Coleoptera: Scolytidae), is one of the most serious destructive pests of oriental spruce (Picea orientalis L.). In order to find an effective biocontrol agent against this pest, we determined the effectiveness of entomopathogenic fungi against D. micans. Virulence of nine highly pathogenic strains including Beauveria bassiana (2), Beauveria cf. bassiana (2), Metarhizium anisopliae (2), Metarhizium sp. (1), Isaria fumosorosea (1) and Evlachovaea sp. (1) was evaluated on D. micans larvae and adults under laboratory conditions. Mortality values for both larvae and adults ranged from 83 to 100% and from 23 to 100%, respectively. Larvae were more susceptible to fungi than adults (P<0.05). Based on screening tests, B. cf. bassiana isolate KTU-53 was found the most effective isolate. LC50 values were calculated as 1.77×104 and 2.65×104 conidia mL?1 for isolate KTU-53 against larvae and adults, respectively. Consequently, B. cf. bassiana isolate KTU-53 appears to be the most promising microbial control agent for biocontrol of D. micans. 相似文献
102.
M. A. Latif Mohd Yosuh Omar Soon Guan Tan S.S. Siraj Abdul Rahim Ismail 《Insect Science》2010,17(6):517-526
Abstract Two sympatric populations of brown planthopper (BPH), one from rice and the other from Leersia hexandra were collected from each of five locations in Malaysia. All the tested malathion-resistant individuals of the rice BPH population and F1 generation (cross between malathion-resistant [usually caught on rice] and malathion-susceptible [usually caught on Leersia]) showed high esterase activity, while all malathion-susceptible individuals on L. hexandra showed low esterase activity. In the F2 generation, all the individuals tested against malathion were approximately 75% resistant and 25% susceptible and the inheritance pattern of esterase activity (high and low esterase activity) segregated in the same manner to a 3: 1 ratio. This confirms that resistance to malathion is mono-factorial and inheritance pattern of esterase activity is also linked to malathion resistance. Carboxylesterase or total esterase activity in BPH is inherited in a simple Mendelian fashion that is encoded by a single dominant gene. For the total esterase assay, average esterase activity levels in the rice-infesting population ranged from 17.64 to 19.37 nmoles 1-napthol/mg protein while that in the Leersia-infesting population ranged from 5.29 to 6.11 nmoles 1-napthol/mg protein. In terms of esterase activity, the two sympatric Nilaparvata lugens populations separated into two distinct groups. Results based on the tube color intensity test showed 96% and 98% resistant and susceptible individuals were present in the rice- and Leersia-infesting populations, respectively. In a filter paper test, the rice-infesting population had 94% with high esterase activity while the Leersia-infesting population had 96% with low esterase activity. 相似文献
103.
El-Shahawy IS 《Memórias do Instituto Oswaldo Cruz》2010,105(8):965-969
Coprological examination of 15 Indian peacocks, Pavo cristatus, revealed the presence of a coccidium species of the genus Eimeria, which apparently represents a previously undescribed species. Sporulation is exogenous and fully developed oocysts of Eimeria pavoaegyptica sp. nov. are ellipsoidal, with a dimension of 15 (13-16) × 12 (10-12.9) microm and with a shape index of 1.25 (1-1.3). The sporulated oocysts have no micropyle but enclose one large rectangular-shaped polar granule and an oocyst residuum. The oocysts have a distinct two-layered wall, which is ~approximately1.7 microm thick. The outer layer has a smooth texture; it fills ~? of the total thickness and appears bicolored. The sporocysts are boat-shaped, of about 10 (9-11) × 4 (4-4.7) microm; their average shape-index is 2.5 microm with a small pointed Stieda body and a smooth, thin single-layered wall. No substieda body is detected. The sporocysts contain numerous, nearly uniform granular residua. The sporozoites are banana-shaped, 6 × 3 microm and each has two different-sized refractile bodies. 相似文献
104.
The changes in the fresh biomass accumulation, photosynthetic and anthocyanin pigments, photosystem 2 (PS 2) activity, ultrastructure
of chloroplast, total lipids and fatty acid composition of thylakoid membrane were followed in the aquatic fern Azolla caroliniana grown on medium either deficient or supplied with various phosphorus concentrations. The content of photosynthetic pigments
and the anthocyanin/chlorophyll ratio increased significantly with increasing PO4
3− concentration. Phosphate deficiency inhibited growth and PS 2 activity and decreased content of total lipids and phospholipids
in isolated thylakoids. This was accompanied with a significant increase in the percentage of galalactolipids. 相似文献
105.
Potassium for better crop production and quality 总被引:3,自引:0,他引:3
Ismail Cakmak 《Plant and Soil》2010,326(1-2):1-2
106.
Namrata Singh Trang T. M. Dang Georgina V. Vergara Dev Mani Pandey Darlene Sanchez C. N. Neeraja Endang M. Septiningsih Merlyn Mendioro Evelyn Mae Tecson-Mendoza Abdelbagi M. Ismail David J. Mackill Sigrid Heuer 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,121(8):1441-1453
107.
BACTIBASE second release: a database and tool platform for bacteriocin characterization 总被引:2,自引:0,他引:2
Riadh Hammami Abdelmajid Zouhir Christophe Le Lay Jeannette Ben Hamida Ismail Fliss 《BMC microbiology》2010,10(1):22
Background
BACTIBASE is an integrated open-access database designed for the characterization of bacterial antimicrobial peptides, commonly known as bacteriocins. 相似文献108.
109.
Denise S. H. Tan Yuchen Ang Gwynne S. Lim Mirza Rifqi Bin Ismail Rudolf Meier 《Zoologica scripta》2010,39(1):51-61
Tan, D. S. H., Ang, Y., Lim, G. S., Ismail, M. R. B. & Meier, R. (2010). From ‘cryptic species’ to integrative taxonomy: an iterative process involving DNA sequences, morphology, and behaviour leads to the resurrection of Sepsis pyrrhosoma (Sepsidae: Diptera). —Zoologica Scripta, 39, 51–61. The increased availability of DNA sequences has led to a surge of ‘cryptic species’ in the literature. These units are usually proposed based on finding genetically distinct lineages within species that were initially defined based on morphological characters. However, few authors attempt to confirm whether these ‘cryptic’ units are species and even fewer authors are explicit about which species concept is applied. Here, we use an example from Sepsidae (Diptera) to demonstrate how cryptic species can be validated by an iterative process involving several data sources and an evaluation of the data under different species concepts. A phylogeographic analysis based on 50 specimens for five species of the flavimana group revealed deep mitochondrial splits within Sepsis flavimana which was suggestive of a cryptic species. We resolve the initial conflict between DNA sequences and morphology by adding new morphological data as well as behavioural evidence and tests for reproductive isolation. One cryptic species is confirmed and Sepsis pyrrhosoma, a former synonym of S. flavimana, is here shown to be a valid species under most species concepts. We can thus document that the same data can lead to similar conclusions under conflicting concepts once different kinds of data are integrated. 相似文献
110.