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981.
R J Warren N L Schauer J T Jones P F Scanlon R L Kirkpatrick 《Journal of wildlife diseases》1979,15(4):537-541
A modified syringe capable of automatic injection and suitable for use with a blow-gun is described. The syringe has been used successfully with white-tailed deer (Odocoileus virginianus) under confined conditions. Desirable characteristics for blow-gun syringes are discussed. 相似文献
982.
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985.
1. For herbivorous insects, the incorporation of a novel host into the diet, and subsequent formation of distinct host associations (races), is thought to be a significant early step in the speciation process. While many studies have addressed this issue, virtually nothing is known about the evolutionary response of natural enemies to herbivore host‐race formation. 2. The hypothesis that the parasitoid wasp Eurytoma gigantea (Hymenoptera: Eurytomidae) has formed host races in direct response to the host shift and subsequent host‐race formation by its host, the gallmaker Eurosta solidaginis (Diptera: Tephritidae) was tested. Emergence time, mating preference, and female oviposition preference were determined for parasitoids derived from galls of each Eurosta host race. 3. Male and female E. gigantea overlap broadly in their emergence times from each Eurosta host race, suggesting that there is no phenological barrier to gene flow. 4. In choice experiments, female parasitoids did not mate assortatively: females that emerged from one Eurosta host race were equally likely to mate with males from either Eurosta host race. 5. Oviposition behaviour experiments revealed that female parasitoids do not prefer to oviposit on their host race of origin and that there is no overall preference for one host race, even though fitness is higher when parasitoids are reared from Eurosta galls of the Solidago gigantea host race than when reared from Eurosta galls of the Solidago altissima host race. 6. These results suggest that E. gigantea has not diverged in parallel with its host in response to the herbivore host‐plant shift. Further studies are needed before the ubiquity of this diversification mechanism can be evaluated fully. 相似文献
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987.
Inbred lines of maize selected as tolerant and intolerant to low-P stress using a sand-alumina culture medium were used to obtain F1 hybrids and advanced generations to be evaluated in diallel mating schemes and generation means analyses for the inheritance studies. Sand-alumina, a solid culture medium, which simulates a slow release, diffusion-limited P movement in soil solution was used in the inheritance studies. Tolerance to low-P stress conditions in maize seedlings is controlled largely by additive gene effects, but dominance is also important. 相似文献
988.
989.
Begoa Martínez‐Cruz Victor A. David Jos A. Godoy Juan J. Negro Stephen J. O'Brien Warren E. Johnson 《Molecular ecology resources》2002,2(3):323-326
Here we describe the development of 18 polymorphic microsatellite markers for the endangered Spanish imperial eagle (Aquila adalberti). Microsatellites were tested in five other raptor species. These markers were revealed as good molecular tools for genetic population studies, individual identification and parentage assessment in Spanish imperial eagle and closely related species. 相似文献
990.
Identification of a short sequence essential for actin binding by Dictyostelium ABP-120 总被引:14,自引:0,他引:14
Tryptic digestion of ABP-120, an actin cross-linking protein from Dictyostelium discoideum, generates a ladder of peptides differing in molecular mass by 13,000 daltons, indicating a structural repeat within the molecule. A number of peptides bind actin with the smallest having a molecular mass of 17,000 daltons (T17). Our sedimentation assays also show that a peptide of 14,000 daltons does not bind actin. Using the full-length cDNA sequence (Noegel, A., Rapp, S., Lottspeich, F., Schleicher, M., and Stewart, M. (1989) J. Cell Biol. 109, 607-618) and protein sequencing techniques, we have determined that T17 begins at residue 89 while T14 begins at residue 116. Therefore we have localized 27 amino acids which are essential for actin binding activity. This region is at the end of the molecule, distal from the repetitive beta-sheet region predicted from the cDNA sequence, and displays high sequence identity with regions in the N termini of ABP/filamin, dystrophin, beta-spectrin, and alpha-actinin. 相似文献