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991.
The mud crab Scylla paramamosain is a widely farmed commercial species in southeast coastal areas of China. The crabs are placed in water-free containers for transportation to inland markets, thus are exposed to dry conditions for more than 72 h after capture and may suffer from air exposure stress, triggering cell apoptosis leading to death. To evaluate whether an inhibitor of apoptosis protein (IAP) is involved in apoptosis resistance against air exposure stress in crustaceans, SpIAP was cloned and investigated for the first time. The full length of SpIAP was 3351 bp, encoding a polypeptide of 662 amino acids. The predicted SpIAP protein contained three baculoviral IAP repeat domains and one really interesting new gene (RING) finger domain. Protein basic local alignment search tool and phylogenetic analysis results showed that SpIAP was clustered together with other crustaceans IAPs. SpIAP was detected in all the examined tissues and predominantly expressed in the hepatopancreas. When crabs were challenged with air exposure for 12 h, the expression level of SpIAP in the hepatopancreas was significantly increased in the experimental group compared with the control group. A RNA interference assay and flow cytometry analysis showed that when SpIAP was silenced, the cell apoptotic rate significantly increased after 24 h air exposure. These results suggested that SpIAP was involved in an anti-apoptosis response induced by air exposure in S. paramamosain. 相似文献
992.
Hui Fang Huiping Zhou Soum Sanogo Robert Flynn Richard G. Percy Sidney E. Hughs Mauricio Ulloa Don C. Jones Jinfa Zhang 《Euphytica》2013,194(1):79-91
Verticillium wilt (VW), caused by Verticillium dahliae Kleb., is one of the most important diseases in cotton. The objective of this study was to map quantitative trait loci (QTLs) conferring VW resistance using resistance gene analog (RGA)-targeted amplified fragment length polymorphism (RGA-AFLP) markers in an interspecific backcross inbred line mapping population, consisting of 146 lines from a susceptible Sure-Grow 747 (Gossypium hirsutum L.) × resistant Pima S-7 (G. barbadense L.) cross. VW resistance was evaluated in replicated tests based on disease incidence in the field, and disease incidence and severity in the greenhouse. Of 160 polymorphic RGA-AFLP markers, 42 were significantly correlated with one or more VW traits and 41 were placed on a linkage map which covered 1,226 cM of the cotton genome and contained 251 other molecular markers. Three QTLs for VW resistance were detected, each of which explained 12.0–18.6 % of the phenotypic variation. Two of these QTLs for disease incidence and severity detected in the greenhouse inoculation tests using root wounding are located on chromosome c4. Both are closely linked to four RGA-AFLP markers and therefore considered as the same QTL for VW resistance. The other QTL detected in the field test was located on c19 and flanked by several RGA-AFLP markers. The desirable QTL allele on c4 for VW resistance detected in the greenhouse was from the VW susceptible Upland parent and absent from the resistant Pima parent which was more VW susceptible due to the disarmament of the first line of defense mechanism due to root wounding during inoculation. The other desirable VW resistance QTL allele, on c19, was from the resistant parent Pima S-7, consistent with the fact that Pima cotton was more resistant to VW when naturally infected in the field. The results should facilitate the development of more sequence specific markers and the transfer of VW resistance from Pima to Upland cotton through marker-assisted selection. 相似文献
993.
Inge M. Hanssen Anneleen Paeleman Lieve Wittemans Kris Goen Bart Lievens Claude Bragard Alfons C. R. C. Vanachter Bart P. H. J. Thomma 《European journal of plant pathology / European Foundation for Plant Pathology》2008,121(2):131-146
Over a period of a few years, Pepino mosaic virus (PepMV) has become one of the most important viral diseases in tomato production worldwide. Infection by PepMV can cause
a broad range of symptoms on tomato plants, often leading to significant financial losses. At present, five PepMV genotypes
(EU, LP, CH2, US1 and US2) have been described, three of which (EU, LP and US2) have been reported in Europe. Thus far, no
correlation has been found between different PepMV genotypes and the symptoms expressed in infected plants. In this paper,
the genetic diversity of the PepMV population in Belgian greenhouses is studied and related to symptom development in tomato
crops. A novel assay based on restriction fragment length polymorphism (RFLP) was developed to discriminate between the different
PepMV genotypes. Both RFLP and sequence analysis revealed the occurrence of two genotypes, the EU genotype and the CH2 genotype,
within tomato production in Belgium. Whereas no differences were observed in symptom expression between plants infected by
one of the two genotypes, co-infection with both genotypes resulted in more severe PepMV symptoms. Furthermore, our study
revealed that PepMV recombinants frequently occur in mixed infections under natural conditions. This may possibly result in
the generation of viral variants with increased aggressiveness. 相似文献
994.
Sarika Mathure Asif Shaikh N. Renuka Kantilal Wakte Narendra Jawali Ratnakar Thengane Altafhusain Nadaf 《Euphytica》2011,179(2):237-246
Eighty-eight aromatic cultivars collected from Maharashtra state were assessed for determinants of kernel quality (kernel
size-shape, test weight and aroma) and grain morphology such as awning, lemma and palea characters, pubescence, colour of
sterile lemma and apiculus colour. We, report seven cultivars—‘Girga’, ‘Kothmirsal’, ‘Kala bhat’, ‘Chimansal’, ‘Jiri’, ‘Kalsal’
‘Velchi’ and ‘Kali kumud’ as indigenous to southern India. Of the 69 cultivars characterized for agronomic traits 36 cultivars
were exquisite genotypes and possessed one or more superior traits such as early flowering, dwarf stature, higher number of
productive tiller per plant; long panicles; higher number of filled grains per panicle and strong aroma. Variability in aromatic
cultivars was assessed on the basis of nine traits placed aromatic rice cultivars in five clusters. Number of cultivars in
each cluster ranged from 1 to 33. 27 significant correlations were obtained in the physical, agronomic and grain morphology
traits. Aroma was found to be negatively associated with days to 50% flowering as well as with filled grains per panicle.
However, correlation between panicle length and effective tillers with aroma was not observed. Therefore, to increase the
yield, improvement in length of panicle and increasing number of productive tillers in medium or mild scented cultivars would
be the best strategy. 相似文献
995.
Yuuri Hirooka Takao Kobayashi Jun Takeuchi Tsuyoshi Ono Yasunori Ono Keiko T. Natsuaki 《Journal of General Plant Pathology》2007,73(5):330-335
A ring spot disease of Aloe vera was found on leaves of potted seedlings of Aloe vera in Hachijojima and Chichijima Islands, Tokyo. From tissue of ring spot lesions, a fungus producing Fusarium-type conidia was consistently isolated. After 1 month, reddish perithecia of nectriaceous fungus had formed on the colonies
of this isolate on PDA. These nectriaceous and Fusarium fungi were identified as Haematonectria haematococca and Fusarium sp., respectively. From a single ascospore isolation, the former was confirmed to be the teleomorph of the Fusarium sp. Typical ring spot lesions were reproduced by artificial inoculations using single ascospore and single conidium isolates.
Inoculations of five species of genus Aloe revealed that they were highly susceptible except for A. arborescens. This is the first report of a disease on Aloe caused by H. haematococca (anamorph: Fusarium sp.) in Japan, and it was named aloe ring spot. 相似文献
996.
The life cycle of Hedruris spinigera Baylis, 1931 (Nematoda: Hedruridae) is determined here with the first formal identification of the parasite's intermediate host: the crustacean amphipod Paracorophium excavatum Thomson. Adult H. spinigera are redescribed from specimens collected from the stomach of fishes, Retropinna retropinna (Richardson) and Aldrichettaforsteri (Valenciennes), from Lake Waihola, New Zealand. Immature adults of the parasite collected from intermediate hosts (P. excavatum) are also described for the first time. The prevalence, abundance and intensity of infection of H. spinigera in several fish species are quantified along with the occurrence of P. excavatum, the parasite's intermediate host, in fish stomach contents. Although H. spinigera's transmission mode (trophic transmission) and fish diet potentially expose all fish species to infection, some level of host specificity must exist as parasite prevalence, abundance and intensity of infection vary greatly between potential definitive host species. We suggest here that the anatomy of the fish digestive tract and especially that of the stomach plays an important role in host suitability for H. spinigera. While P. excavatum is the only intermediate host in Lake Waihola, H. spinigera was found in six different fish species: Aldrichetta forsteri, Galaxias maculatus (Jenyns), Retropinna retropinna, Rhombosolea retiaria Hutton, Perca fluviatilis Linnaeus and Salmo trutta Linnaeus; although typical hedrurid attachment and mating positions were observed only in R. retropinna and A. forsteri. The limited distribution of H. spinigera is most likely due to that of its different host species (intermediate and definitive), all inhabitants of coastal fresh and brackish waters. 相似文献
997.
Atiqur Rahman Barbhuiya Ayyanadar Arunachalam Prabhat Chandra Nath Mohammed Latif Khan Kusum Arunachalam 《Journal of Forest Research》2008,13(1):25-34
Rates of weight loss and nutrient (N and P) release patterns were studied in the leaf litter of the dominant tree species
(Ailanthus grandis, Altingia excelsa, Castanopsis indica, Duabanga sonneriatioides, Dysoxylum binectariferum, Mesua ferrea,
Shorea assamica, Taluma hodgsonii, Terminalia myriocarpa and Vatica lancefolia) of a tropical wet evergreen forest of northeast India. Nitrogen and phosphorus mineralization rate and decay pattern varied
significantly from species to species. In general, the decay pattern, characterized by using a composite polynomial regression
equation, exhibited three distinct phases of decay during litter decomposition—an initial slow decay phase (0.063% weight
loss day−1), followed by a rapid decay phase (0.494% weight loss day−1) and a final slow decay phase (0.136% weight loss day−1). The initial chemical composition of the litter affected decomposition rates and patterns. Species like D. sonneriatoides, D. binectariferum, and T. hodgsonii with higher N and P content, lower carbon and lignin content, and lower C:N ratio and lignin:N ratio exhibited relatively
faster decomposition rates than the other species, for example M. ferrea, C. indica and A. grandis. A slow decay rate was recorded for species such as M. ferrea, C. indica, and A. grandis. The initial N and P content of litter showed significant positive correlations with decay rates. Carbon and lignin content,
lignin:N, and C:N showed significant negative correlations with decay rates. Soil total N and P, and rainfall, soil temperature,
and soil moisture had positive correlations with decay rates. The rapid decomposition rates observed in comparison with other
different forest litter decay rates confirm that tropical wet evergreen forest species are characterized by faster decomposition
rates, indicating a faster rate of organic matter turnover and rapid nutrient cycling. 相似文献
998.
Umma Tamima 《林业研究》2016,27(4):853-861
The objective was to evaluate the performance of the co-management of Nishorgo Support Project at Chunati Wildlife Sanctuary in Bangladesh. I adopted the Focus Groups Discussion method for opinion survey and applied the SWOTAHP technique for data analysis. Local people did not participate in the decision-making process of forest management and they perceived co-management as a threat to their livelihoods. Moreover, mistrust and misunderstanding among different stakeholders, political and ethical conflicts, lack of property rights of tribal communities, and lack of accountability and transparency were identified as the drawbacks of co-management. 相似文献
999.
Salwinder S. Dhaliwal Gurpal S. Toor Ignacio A. Rodriguez-Jorquera Todd Z. Osborne Susan Newman 《Journal of Soils and Sediments》2018,18(2):342-351
Purpose
Inorganic contaminants present a major challenge for the restoration of aquatic ecosystems. The objectives of this study were to determine the extent of trace metal contamination and investigate the influence of different plant communities on trace metal accumulation in the soils of the Florida Everglades.Materials and methods
Soil samples (n?=?117) were collected from 0 to 10-cm depth using a stainless steel coring device from sites with three dominant plant communities—cattail, sawgrass, and slough—of Water Conservation Area-2A (43,281 ha) of Florida Everglades.Results and discussion
The mean pH in soils collected from three plant communities was 6.75–6.82, whereas electrical conductivity was slightly greater in the sawgrass (0.69 dS m?1) than cattail (0.58 dS m?1) and slough (0.40 dS m?1). Mean reduction–oxidation potential was greatest in cattail (?113 mV) than sawgrass (?85.3 mV) and slough (?48.3 mV) soils. Among 11 trace metals (As, B, Co, Cr, Cu, Mn, Mo, Na, Ni, Pb, Zn) found in soil samples, Na had the greatest contents and was greater in cattail (2070 mg kg?1) and sawgrass (1735 mg kg?1) than slough (1297 mg kg?1). Four trace metals (B, Cu, Mo, Ni) were significantly greater in cattail than sawgrass and slough. Whereas, Mn was significantly lower in cattail (31 mg kg?1) than both sawgrass (84 mg kg?1) and slough (51 mg kg?1). Cattail also had significantly lower Cr (1.97 mg kg?1) and Pb (10 mg kg?1) than sawgrass (Cr 2.5 mg kg?1; Pb 20.8 mg kg?1). As (<6.9 mg kg?1), Co (<1.3 mg kg?1), and Zn (<17.2 mg kg?1) were not significantly different among soils collected from three plant community-dominant sites. Contents of Cd and Se were below the method detection limits (Cd 0.01 mg L?1; Se 0.2 mg L?1) and are not reported.Conclusions
None of the trace metals in the soils exceeded the US Environmental Protection Agency sediment toxicity thresholds. Results from this study provided baseline concentrations of trace metals, which can be used to measure the success of restoration efforts in Florida Everglades.1000.
Paula Martins-Lopes José Lima-Brito Sónia Gomes Julieta Meirinhos Luís Santos Henrique Guedes-Pinto 《Genetic Resources and Crop Evolution》2007,54(1):117-128
Thirty Portuguese and eight foreign olive (Olea europaea L.) cultivars were screened using Random Amplified Polymorphic DNA (RAPD) and Inter-Simple Sequence Repeat (ISSR) markers.
Twenty RAPD primers amplified 301 reproducible bands of which 262 were polymorphic; and 17 ISSR primers amplified 204 bands
of which 180 were polymorphic. The percentage of polymorphic bands detected by ISSR and RAPD was similar (88 and 87%, respectively).
The genetic variability observed was similar in the Portuguese and foreign olive cultivars. Seven ISSR and 12 RAPD primers
were able to distinguish individually all 38 olive cultivars. Twenty specific molecular markers are now available to be converted
into Sequence Characterised Amplified Region (SCAR) markers. Relationships among Portuguese and foreign cultivars is discussed. 相似文献