Biological control of the charcoal root rot fungus Macrophomina phaseolina on slash pine seedlings by a hyperparasite     

R.E. De La Cruz  D.H. Hubbell 《Soil biology & biochemistry》1975,7(1):25-30

Macrophomina phaseolina. the cause of damping-off and charcoal root rot disease on slash pine seedlings (Pinus elliottii Engelm var. elliottii), was antagonized by an unidentified basidiomycete species under laboratory and nursery conditions. Aseptically-grown slash pine seedlings died 3 days after inoculation with M. phaseolina, whereas seedlings inoculated with the basidiomycete sp., or basidiomycete sp. plus M. phaseolina, and uninoculated controls were alive after 6 months. In nursery studies, survival of slash pine seedlings in plots inoculated with M. phaseolina was significantly lower (57 per cent) than survival resulting from inoculations with the basidiomycete sp. (90 per cent), or basidiomycete sp. plus M. phaseolina (84 per cent), and the uninoculated controls (81 per cent). Electron microscopy showed that the basidiomycete sp. is a hyperparasite on mycelia of M. phaseolina. Preliminary evidence indicates that the hyperparasite is not host-specific but will infect other fungal pathogens. Two ectomycorrhizal fungi were not parasitized by the basidiomycete.  相似文献   

同时检测两种对虾病毒和4种弧菌的同步PCR方法的建立   总被引：3，自引：1，他引：2  

许拉  黄使  戈蕾  杨冰 《海洋水产研究》2008,29(4)

通过检索、多重比对、分析和筛选GenBank中对虾白斑综合征病毒(WSSV)、传染性皮下和造血器官坏死病毒(IHHNV)、副溶血孤菌、创伤弧菌、哈维氏弧菌和溶藻胶弧菌的基因序列,设计了10对特异性引物,以已知毒株和菌株的DNA为模板进行PCR,均能扩增出与实验设计相符合的DNA片段,对PCR扩增条件进行优化,建立了可同时检测鉴别WSSV、IHHNV、副溶血弧菌、创伤弧菌、哈维氏弧菌和溶藻胶弧菌,并且能同时区分WSSV不同地理毒株的同步PCR方法.研究结果表明,该方法检测特异性好,检测通量大,适合于对虾多种病原的同时检测.  相似文献   

Population structure of purple sea urchin <Emphasis Type="Italic">Strongylocentrotus purpuratus</Emphasis> along the Baja California peninsula     

Nadia C Olivares-Bañuelos  Luís M Enríquez-Paredes  Lydia B Ladah  Jorge De La Rosa-Vélez 《Fisheries Science》2008,74(4):804-812

Abstract:   Purple sea urchin Strongylocentrotus purpuratus is fished from British Columbia, Canada to Punta Baja, Mexico. The North American population has been divided into northern and southern fishery stocks at the break of Point Conception, but little is known about its southernmost distribution along the Mexican Pacific coast of the Baja California peninsula. In this study purple sea urchin populations in six sites along the Baja California peninsula were analyzed using mitochondrial deoxyribonucleic acid restriction fragment length polymorphism (mtDNA RFLP). A homogeneous distribution of three common haplotypes among all sites was observed. A significant F _ST value, however, indicated genetic structure mainly due to the haplotype array in San Miguel, Isla Todos Santos and Punta Baja sites, which were characterized by having high haplotype diversity and several unique haplotypes. Homogeneous distribution of haplotypes along the peninsula could have been influenced by the unidirectional California Current system, flowing north to south. Unique haplotypes in Punta Baja and the structure found could be the result of local oceanographic features specific to this major upwelling zone. It may be necessary to consider the Punta Baja populations individually when managing the purple sea urchin fishery in Baja California, as they show signs of being a unique stock.  相似文献   

Contribution of the microbial and meat endogenous enzymes to the free amino acid and amine contents of dry fermented sausages.   总被引：5，自引：0，他引：5  

E Hierro  L de La Hoz  J A Ordó?ez 《Journal of agricultural and food chemistry》1999,47(3):1156-1161

The role of the starter culture and meat endogenous enzymes on the free amino acid and amine contents of dry fermented sausages was studied. Five batches of sausages were prepared. The control batch was manufactured with aseptic ingredients without microbial inoculation. The other four experimental batches were manufactured with aseptic ingredients inoculated with Lactobacillus plantarum 4045 or Micrococcus-12 or L. plantarum 4045 and Micrococcus-12 or L. plantarum 4045 and Staphylococcus sp. Their effects on pH, a(w), myofibrillar proteins, and free amino acid and amine contents were studied. Sausages inoculated only with L. plantarum 4045 or with this starter combined with a Micrococcaceae had the lowest pH as a result of carbohydrate fermentation. In all batches similar patterns were observed for myofibrillar proteins and free amino acids which could indicate that meat endogenous proteases play an important role in proteolytic phenomena. No changes were observed in the amine fraction, indicating that the strains used as starter cultures did not show amino acid decarboxylase activity.  相似文献   

Early life history of the black anglerfish Lophius budegassa Spinola, 1807 in the Mediterranean Sea using otolith microstructure     

Mario La Mesa  Francesca De Rossi 《Fisheries Research》2008,93(1-2):234-239

The early life history of the black anglerfish, Lophius budegassa was investigated by otolith (lapilli) increment analysis. Samples of demersal juvenile L. budegassa ranging from 54 to 196 mm total length were collected during bottom trawl surveys in the central Adriatic Sea. By counting increments presumed to be deposited daily in the lapillar otoliths, 88 specimens of L. budegassa were successfully aged. Age estimates of juveniles ranged between 79 and 204 days, indicating that probably the pelagic phase of this species is relatively short and settlement occurs at less than 3 months of life. The analysis of check marks in the core area of lapilli enabled us to determine the period of endogenous feeding, which would last between 15 and 24 days after hatching. Back-calculated hatching dates and, consequently, the spawning season of L. budegassa in the Adriatic Sea was spread over a long period, lasting at least from February to June. The length at age relationship gave an estimate of mean growth rate of approximately 0.8–1.02 mm/day, indicating a faster growth rate of 0+ juveniles L. budegassa than previously thought. The implications of these findings on age estimates discrepancies between previous ageing studies on L. budegassa carried out using different calcified structure (sagittae or illicia) are discussed.  相似文献   

Modeling environmental,temporal and spatial effects on twaite shad (Alosa fallax) by‐catches in the central Mediterranean Sea          下载免费PDF全文

Gabriele La Mesa  Aldo Annunziatellis  Elio Filidei Jr.  Caterina Maria Fortuna 《Fisheries Oceanography》2015,24(2):107-117

Modeling the relationships between environmental factors and the distribution at sea of species of conservation interest can be useful in predicting their occurrence from a local to a regional scale. This information is essential for planning management and conservation initiatives. In this study, generalized additive models (GAMs) were applied to investigate the influence of environmental, temporal and spatial variables on the catch rates of the twaite shad Alosa fallax (Lacepède) by the pelagic trawl fishery in the north‐central Adriatic Sea. Presence/absence and abundance [catch per unit effort (CPUE)] data between 2006 and 2012 were separately modeled, and the two models were then validated using a test data set. The most important factor influencing the presence and abundance of adult twaite shads was the spatial predictor (latitude × longitude). Two areas of major shads aggregations were observed, the most important of which being located near the estuaries of three main river systems of northern Italy. The twaite shad presence was also significantly affected by season, the largest and lowest occurrences being observed in autumn and spring, respectively. Among the environmental variables tested, only sea surface temperature was included in both models. Alosa fallax showed a wide thermal tolerance (6–27°C) with preference for temperature around 23°C. The model developed from the abundance data showed a moderate predictive power, whereas the accuracy of the presence/absence model was rather low. Some conclusions on the ecological requirements of A. fallax at sea arising from this study are useful to orient future monitoring and research programs and to develop effective conservation actions.  相似文献   

Clonal populations of Clavibacter michiganensis subsp. michiganensis are responsible for the outbreaks of bacterial canker in greenhouse tomatoes in Italy          下载免费PDF全文

G. Licciardello  C. P. Strano  R. Eichenlaub  K.‐H. Gartemann  R. La Rosa  V. Catara 《Plant pathology》2016,65(3):484-495

Clavibacter michiganensis subsp. michiganensis (Cmm) strains, collected in greenhouses from 17 farms during tomato bacterial canker outbreaks occurring between 2005 and 2008 in Sicily, were analysed by a multiphasic approach. Population studies were conducted to investigate the possible sources of inocula. Cmm strains were characterized by PCR assays targeting virulence genes, fingerprinting techniques, metabolic profiles and virulence. These strains were comparatively analysed with Cmm strains isolated in other parts of Italy over a period of 15 years. Chromosomal genes encoding virulence determinants tomA, ppaA, chpC, and the plasmid‐encoded genes pat‐1 and celA were detected by PCR in all tested strains, except for four Sicilian Cmm strains where the pat‐1 gene was not amplified. Using BOX‐PCR, Cmm strains were differentiated into 13 haplotypes and clonal populations were identified. Cmm strains isolated from different farms in 2008 showed the same BOX‐PCR haplotype. A distinct BOX‐PCR haplotype was obtained from atypical Cmm strains lacking pat‐1 and isolated in 2006/7 from three farms. Cmm strains with two different haplotypes were detected in one farm, whereas the other farms contained strains with only a single haplotype. A new fAFLP protocol based on the amplification of ApaI/MseI fragments was developed and was able to differentiate C. michiganensis subspecies. Different populations were delineated for the multiple outbreaks occurring in Sicily, whereas similar populations were recorded in other Italian regions over a period of 12 years. The results are consistent with previous studies that demonstrate that Cmm outbreaks are associated with propagation material.  相似文献   

Effects of insecticide Thiodan® on the morphology and quantification of ovarian follicles in lambaris Astyanax bimaculatus (Linnaeus, 1758) in different treatments          下载免费PDF全文

Lucas Marcon  Ann Honor Mounteer  Nilo Bazzoli  Laércio dos Anjos Benjamin 《Aquaculture Research》2016,47(8):2407-2418

Thiodan^® is an insecticide which can cause morphological changes in fish tissues, dependent on the concentration. To investigate possible morphological changes, this study evaluated the number and diameter of ovarian follicles in lambaris Astyanax bimaculatus exposed to Thiodan^® for 96 h in different treatments at three sub‐lethal concentrations: 1.15, 2.3 and 5.6 μg L^?1 and a control group without Thiodan^®. Females exposed to Thiodan^® were divided into four treatments: (i) without acclimation and without food, (ii) without acclimation and with food, (iii) with acclimation for 10 days and without food; (iv) with acclimation for 10 days and with food. In this study, it was noted that the action of Thiodan^® at sub‐lethal concentrations in a static system did not affect the morphology of follicular development. However, the treatments with acclimation showed lower numbers of primary and secondary follicles when compared to fish from treatments without acclimation. For the groups exposed to Thiodan^®, a greater number of atretic follicles were observed compared to the control groups. The follicular diameter of secondary follicles in fish exposed to Thiodan^® in the treatment with acclimation and with food was highest in the control group (P < 0.05). Furthermore, the mean gonadosomatic (GSI) and hepatosomatic (HSI) indices of treatments with acclimation were lower than those for treatments without acclimation. These data suggest that the fish may be being affected by the pesticide to which the fish were submitted, and may cause impairment to the follicular development.  相似文献   

Effect of poly(dl-lactide-co-glycolide) nanoparticles or cellulose nanocrystals-based formulations on Pseudomonas syringae pv. tomato (Pst) and tomato plant development     

Fortunati  Elena  Rescignano  Nicoletta  Botticella  Ermelinda  La Fiandra  Domenico  Renzi  Marsilio  Mazzaglia  Angelo  Torre  Luigi  Kenny  Josè Maria  Balestra  Giorgio Mariano 《植物病害和植物保护杂志》2016,123(6):301-310

Journal of Plant Diseases and Protection - Nanotechnology can change the scenario of current tools minimizing the chemical inputs in plant protection. Here, novel poly(dl-lactide-co-glycolide acid)...  相似文献   

The Effect of Drought Stress on Nutraceutical Properties of <Emphasis Type="Italic">Zea mays</Emphasis> Bran     

E. Lugo-Cruz  F. Zavala-García  H. Rodríguez-Fuentes  V. Urías-Orona  J. A. Vidales-Contreras  R. Carranza-De La Rosa  G. Niño-Medina 《Gesunde Pflanzen》2018,70(4):179-184

The effect of drought stress on total phenols, hydroxycinnamic acids, and antioxidant capacity in Cebú, DK2027, and DK2034 maize hybrids was evaluated. Compared to irrigation treatment, total phenols decreased in drought stress treatment by 35.34%, 5.59%, and 31.57% in Cebú, DK2027, and DK2034, respectively. In addition, the levels of t-ferulic, c-ferulic and p-coumaric acids decreased by 17.74%, 23.93%, and 29.83% in Cebú, by 8.92%, 8.62%, and 24.03% in DK2027, and by 13.66%, 11.03%, and 10.38% in DK2034, respectively. The predominant hydroxycinnamic acid from bran extracts was t-ferulic (67% to 72%), followed by c-ferulic (20% to 21%), and p-coumaric (7% to 11%) for both irrigation and drought stress treatments, while caffeic and sinapic acids were found in traces or were not detected. The antioxidant capacity decreased by 8%, 3%, and 9% in trolox equivalents and 7%, 17%, and 14% in percentage of radical scavenging activity for Cebú, DK2027, and DK2034 genotypes, respectively. The reduction of total phenols, hydroxycinnamic acids, and antioxidant capacity is due to the radical scavenging and photoprotective actions of hydroxycinnamic acids against highly reactive oxygen species generated under drought stress treatment.  相似文献