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61.
Archaeological surveys in woodland have always been problematicand many woodlands contain an unrecorded archaeological resource.For other types of rural landscape, aerial photographs are oftenused to map archaeological features but woodland cover has alwaysimpeded such disclosure. Remote sensing methods are rapidlyevolving and are used both within forestry and archaeologicaldisciplines for a range of applications. This paper considersthe exciting application of the remote sensing technique ofairborne Light Detection and Ranging (LiDAR) to reveal archaeologicalevidence previously hidden below a woodland canopy. Our researchshows how different types of woodland canopy and understoreyvegetation greatly influence the effectiveness of the LiDARto perform these surveys. A simple, visual vegetation mappingassessment is tested and its ability to predict the potentialof the LiDAR considered. This work highlights the importanceof vegetation awareness when considering both a new LiDAR surveyfor a woodland, and when interpreting the data. Simple estimatesof LiDAR penetration of the woodland canopy and understoreyvegetation can be used to predict the effectiveness of a LiDARsurvey in disclosing archaeological evidence and aid the interpretationof results. 相似文献
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63.
The use of characterisation data to establish the Indian mungbean core collection and assessment of genetic diversity 总被引:4,自引:0,他引:4
A representative core set of well characterised Indian mungbean collection was developed using information on passport, characterisation and evaluation data. Initial diversity groups of the accessions comprising the whole collection were formed based on six major crop growing zones and a separate group for a few accessions from diverse exotic sources. Principal components score strategy was found to be most useful in maximising the selection inertia than strictly random sampling in all individual groups. A total of 152 accessions were extracted and the validity of their representativeness was established by comparing its diversity with that of the whole collection. Shannon diversity index for qualitative characters and certain statistical parameters for quantitative variables were used for measuring the diversity of the accessions in the core set and that of the whole collection. The representative core set was subjected to multivariate analysis for assessment of genetic diversity and also the variation patterns for discriminating among accessions to facilitate the users for easy accessibility, and effective and efficient utilisation of the material. 相似文献
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65.
Claire L Price Josie E Parker Andrew GS Warrilow Diane E Kelly Steven L Kelly 《Pest management science》2015,71(8):1054-1058
Plant fungal pathogens can have devastating effects on a wide range of crops, including cereals and fruit (such as wheat and grapes), causing losses in crop yield, which are costly to the agricultural economy and threaten food security. Azole antifungals are the treatment of choice; however, resistance has arisen against these compounds, which could lead to devastating consequences. Therefore, it is important to understand how these fungicides are used and how the resistance arises in order to tackle the problem fully. Here, we give an overview of the problem and discuss the mechanisms that mediate azole resistance in agriculture (point mutations in the CYP51 amino acid sequence, overexpression of the CYP51 enzyme and overexpression of genes encoding efflux pump proteins). © 2015 Society of Chemical Industry 相似文献
66.
Identification of lactoferrin and glutamate receptor‐interacting protein 1 in bovine cervical mucus: A putative marker for oestrous detection
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WY Lee MH Park KW Kim H Song KB Kim CS Lee NK Kim JK Park BC Yang KB Oh GS Im HJ Chung 《Reproduction in domestic animals》2017,52(1):16-23
Accurate detection of oestrus is important for artificial insemination. The aim of this study was to identify oestrous‐specific bovine cervical mucus proteins that could be used to determine the optimal time for artificial insemination. Non‐oestrous and controlled internal drug release (CIDR)‐induced oestrous‐stage mucus proteins were purified and subjected to surface‐enhanced laser desorption/ionization time‐of‐flight mass spectrometry, sodium dodecyl sulphate polyacrylamide gel electrophoresis and MALDI‐TOF/TOF. Among differentially expressed proteins, lactoferrin (LF) and glutamate receptor‐interacting protein 1 (GRIP1) showed a twofold increase during the CIDR‐induced oestrous stage compared to the levels in non‐oestrous stage in bovine cervical mucus. The RT‐PCR, Western blotting and immunohistochemistry results showed that LF and GRIP1 expression was significantly increased during the oestrous stage in the uterus. This study demonstrated that bovine LF and GRIP1 exist during the oestrous stage, but not during the non‐oestrous stage, suggesting that cervical mucus LF and GRIP1 are useful oestrous detection markers in cattle. 相似文献
67.
BZ Yang CY Yang RC Li GS Qin XF Zhang CY Pang MT Chen FX Huang Z Li HY Zheng YJ Huang XW Liang 《Reproduction in domestic animals》2010,45(5):e21-e25
The aim of this study was to explore the feasibility of cryopreservation of inter‐subspecies cloned embryos in buffalo. In our experiment, river buffalo ear fibroblast nucleus was fused into swamp buffalo oocyte cytoplasm. The blastocyst formation rate for nuclear transfer of freshly thawed cells was not different from those of growing cells, confluent or serum‐starved cells. A total of 122 cloned blastocysts derived from cryopreserved fibroblasts were cryopreserved and thawed, 37 were survived, the cryosurvival rate was 30.3%. The survived blastocysts were transferred into 15 recipient buffalos. Five of the recipients established pregnancy, but four of them aborted on day 53, 59, 145 and 179 of gestation respectively. One cross‐bred buffalo (Murrah × Swamp buffalo (2n = 49) received three embryos delivered a 40.5 kg female calf by natural delivery on day 320 of gestation. Up to now (13‐month old), the cloned calf has been growing well with no abnormity observed. These results demonstrated that cryopreservation of inter‐subspecies cloned embryos is feasible to produce buffalo offspring. 相似文献
68.
A field study was designed to compare ovarian response and embryo yield in cows during early lactation when gonadotropin administration followed one of four treatments. In group 1A (n = 19) and 1B (n = 9), the estrouses were synchronized by two prostaglandin F2alpha (PG) injections given 11 days apart, and starting from day 9 of the synchronized cycle superovulation was conducted with eight decreasing dose of FSH. In group 1B, ablation of all follicles >3 mm was carried out on day 8. In group 2A and 2B (each n = 9), a progesterone plus oestradiol intravaginal device (PRID) was inserted for 11 days and gonadotropin administration started on day 9, while cows from group 2B had a follicle ablation on day 8. In all groups, two PG injections were given along with the sixth and the seventh dose of FSH, and the cows were twice inseminated 12 and 24 h after estrus detection. Embryos were collected on day 7. In cumulative results from aspirated and non-aspirated cows, follicular ablation significantly improved: the ovarian response (10 +/- 1.23 vs 6.69 +/- 0.60 corpora lutea per donor), the mean collected embryos (6.57 +/- 0.94 vs 2.46 +/- 0.53) and the mean transferable embryos (4.43 +/- 0.89 vs 2.18 +/- 0.47). Group 1B and 2B cows had better ovarian response than 1A (6.44 +/- 0.81, 12.25 +/- 4.11 and 9.44 +/- 0.93, for groups 1A, 1B and 2B, respectively, p < 0.05). Similarly, from groups 1B and 2B more (p < 0.05) embryos were collected in comparison with their respective group, while the mean transferable embryos from group 2B (5.22 +/- 1.13) was greater (p < 0.05) than that of group 1A (1.67 +/- 0.35), and tented to be greater than those of groups 2A (3.44 +/- 1.19, p = 0.062) and 1B (3.00 +/- 1.78, p = 0.066). The highest (p < 0.05) transferable embryo collection rate was recorded in group 2B (55.29%), followed by that of group 1B (41.33%). In summary, early in lactation, an acceptable number of transferable embryos can be collected from high producing dairy cows, when follicle ablation prior to superovulation is combined with progesterone and oestradiol administration. 相似文献
69.
Vikram S. Bisht Piara S. Bains James R. Letal 《American Journal of Potato Research》1993,70(8):611-616
Limited development of blackleg resistant potato cultivars has been ascribed to the lack of an effective and reliable test for large scale blackleg resistance screening. A method using leaf petioles was developed for assessing susceptibility of potato stems to blackleg pathogens (Erwinia carotovora subspeciesatroseptica andE. c. subspeciescarotovora). Fifty grams of sterile autoclaved silica sand in Magenta jars (GA-7 vessel, Magenta Corp., Chicago, Illinois) was drenched with bacterial suspension, (17 ml, 2.6 × 10 to 2.6 × 107 cfu/ml) and freshly cut petioles from 5 to 6 week-old plants were inserted to about 5 mm into the sand. The Magenta jars with lids closed were kept on a laboratory bench (20 ±2 C, 16 hours light). The arrangement provided near ideal post-inoculation incubation environment of high humidity for pathogen multiplication and rot development in the petioles. Length of rot was recorded 72 hours after inoculation. Linear regression of rot development on inoculum concentration had R2 ≥ 0.80. The petioles inoculated and incubated by this method produced measurable rot lesions with a bacterial concentration as low as 2.6 × 104 cfu/ml and differentiated between the resistant cultivar Russet Burbank and the susceptible cultivar Sangre at all the inoculum concentrations used. Furthermore, susceptibility ranking of five cultivars obtained by this method agreed in general with their reported field reactions. The method is simple and sensitive, and could be used for large scale screening for stem rot resistance in wildSolanum species and early generation breeding populations. 相似文献
70.
Summary Survival of the pathogen causing silver scurf of potato (Helminthosporium solani) in Alberta soils was studied by evaluatingH. solani infection in the progeny ofH. solani-free nuclear seed potato tubers planted in fields where potatoes had never been grown or were grown 1, 2, 3, or 4 years previously.
Daughter tubers from all the fields developed silver scurf lesions, andH. solani was isolated from infected tubers. This is the first report of survival ofH. solani in Alberta soils. Soil-borne inoculum appears to have a role in the epidemiology of the disease and in the introduction of
the pathogen into silver scurf-free potato seed stock. Of 31 plant species tested, only potato was found to be a host ofH. solani. Most of theH. solani isolates from north central Alberta were more sensitive to thiabendazole than those from southern Alberta, where thiabendazole
is much more commonly used. 相似文献