Biological control ofBotrytis cinerea in residues and flowers of Rose (Rosa hybrida)     

Joseli da Silva Tatagiba  Luiz Antonio Maffia  Roberto W. Barreto  Acelino C. Alfenas  John C. Sutton 《Phytoparasitica》1998,26(1):8-19

Microbial isolates from living petals, petal residues and leaf residues of rose, and from laboratory collections, were evaluated for control ofBotrytis cinerea in rose. In leaf residues artificially infested withB. cinerea, isolates of the filamentous fungiGliocladium roseum, FR136 (unidentified) andTrichoderma inhamatum reduced sporulation of the pathogen by >90%, other filamentous fungi were 25–90% effective, and those of yeasts and bacteria were <50% effective. In artificially inoculated petal residues, no microbe reduced sporulation ofB. cinerea by >75%, but isolates ofCladosporium oxysporum and four yeasts were 51–75% effective, and three filamentous fungi, eight yeasts andBacillus subtilis isolates were 26–50% effective. Isolates ofT. inhamatum, C. oxysporum andG. roseum performed best againstB. cinerea among isolates evaluated in leaf residues naturally infested with the pathogen and indigenous microorganisms. Totals of ten isolates of filamentous fungi (includingC. oxysporum andC. cladosporioides), two of yeasts and five ofBacillus subtilis completely prevented lesion production byB. cinerea in detached petals, and a further six isolates of filamentous fungi (includingG. roseum) and six yeasts were 90–99% effective. Isolates ofC. oxysporum, C. cladosporioides andB. subtilis, the most effective microorganisms againstB. cinerea in flower buds, reduced number of lesions in the range of 42–65% compared with 59–89% for à standard fungicide (vinclozolin). It is suggested that application of leading antagonists Jo living rose leaves and flowers should optimize control of inoculum production byB. cinerea when the tissues die. Optimal biocontrol of lesion production in flower buds requires a better understanding of the microenvironment of petals.  相似文献   

Evaluation of Feed Attractants in Juvenile Senegalese Sole,Solea senegalensis     

Fernando G. Barroso  Ana Rodiles  Antonio J. Vizcaino  Tomás F. Martínez  Francisco J. Alarcón 《Journal of the World Aquaculture Society》2013,44(5):682-693

The Senegalese sole, Solea senegalensis, is a flatfish with increasing interest in the European aquaculture. However, one of the main limitations found in this species is related to the scarce attraction to commercial aquafeeds, thus determining low feed intake in fish farms. The aim of this study was to evaluate four ingredients of marine origin (fish meal hydrolysate [FMH], polychaete meal [POM], mussel meal [MUM], and squid meal [SQM]) as potential attractants for juvenile Senegalese sole. Four experimental feeds containing 10% of the potential attractants, plus a control diet without these ingredients, were evaluated. A total of 150 fish were distributed into ten 40‐L tanks (duplicate tanks per feed). A Latin square design was carried out, and hence all the experimental diets were offered to each tank in successive periods of 7 d. Fish were fed twice a day (morning and afternoon), and the feeding behavior of the animals was assessed by direct observations. Behavioral pattern assessed was classified as distant orientation, near orientation, or continuation of intake. The acceptability index for each behavioral phase and experimental feeds used was established for each observation. No behavioral differences could be noticed between the morning and the afternoon feedings. FMH showed the greatest attractant potential than among the ingredients assessed, and consequently this ingredient yielded the higher feed intake rates. On the other hand, POM was not the best attractant for juvenile Senegalese sole.  相似文献   

The effect of being housed with adult female flock-mates on the age at puberty of autumn-born ewe-lambs     

Abecia  José-Alfonso  Barrio  Antonio  Ruiz  José-Antonio 《Veterinary research communications》2022,46(2):609-612

Veterinary Research Communications - Twenty-five ewe-lambs born in November were used to measure the effect of the presence of cyclic or non-cyclic adult ewes on the age at first fertile estrus....  相似文献   

Vulnerability to drought-induced cavitation of riparian cottonwoods in Alberta: a possible factor in the decline of the ecosystem?     

Tyree MT  Kolb KJ  Rood SB  Patiño S 《Tree physiology》1994,14(5):455-466

Vulnerability of xylem to loss of hydraulic conductivity caused by drought-induced cavitation was determined for three riparian cottonwood species in Lethbridge, Alberta: Populus deltoides Bartr., P. balsamifera L., and P. angustifolia James. These species suffered 50% loss of hydraulic conductivity in one-year-old stem segments when xylem pressure potential fell to -0.7 MPa for P. deltoides and -1.7 MPa for P. balsamifera and P. angustifolia, making them the three most vulnerable tree species reported so far in North America. The possible contribution of drought-induced xylem dysfunction to the decline of riparian ecosystems in dammed rivers is discussed.  相似文献   

Effect of water stress conditioning on morphology,physiology and field performance of Pinus halepensis Mill. seedlings     

Royo  Antonio  Gil  Luis  Pardos  José A. 《New Forests》2001,21(2):127-140

Five-month-old Pinus halepensis Mill. seedlings were subjected to 4 irrigation treatments for 8 weeks. After the treatments, morphological and physiologicalattributes assessed included height, diameter, dry weight, water relations parameters, and determination of N, P, K, soluble carbohydrates, and starch concentrations. The remaining seedlings were field planted. Survival and height growth were recorded forfour growing seasons after planting. The mostsignificant effect of irrigation was onmorphology. Increased irrigation lead toseedlings with significantly higher height,root collar diameter and shoot and rootbiomass. Starch and soluble carbohydrateconcentrations were also affected byirrigation. However, parameters derived frompressure-volume curves were not significantlydifferent among treatments, nor were N, P, andK concentrations. There were no differencesamong treatments for survival in the field,which was highly related to summer rainfall. Incomparison, absolute and relative heightgrowth showed some significant but minordifferences among treatments.  相似文献   

Zur Ausbreltung und Biologie der Nordamerikanischen Thujenminiermotte,Argyresthia thuiella Packard (Lep., Argyresthiidae) in Österreich     

em. o. Univ.-Prof. Dr. A. Kurir 《Journal of pest science》1983,56(7):125-128

During the last 12 years Arborvitae Leaf Miner (Argyresthia thuiella) was imported from North America to Western- and Central-Europe (1971 the Netherlands, 1975 Federal Republic Germany and 1976 Austria) onThuja occidentalis L. (Cupressacea). In Lower Austria and Vienna there is a tendency rapid to the east, through the dominate westerly winds. Fligh-time took 27 days, moth-slip was 5–10 h in the morning; maximum about 5–6 h. Index of sexus was displated in favour of the males (51.7–66.7%). The moths fed with water-honey showed a longaevitas of 1–15 days maximum about 4 days, and fed with pure water of 8 days. Attack-degree (variational limit) amounted to 2.6–24.5%. The parasitism-role (Necremnus sp., Eulophidae) was between 1.2% and 15.7%. In the laboratory chemical-therapeutics in spray form were without effect. Author's opinion is that this eminent exotic injurious insect must already be calculated as a part of the European fauna.  相似文献   

Callus formation and cucurbitacin B accumulation in Ecballium elaterium callus cultures     

Toker G  Memişoğlu M  Toker MC  Yeşilada E 《Fitoterapia》2003,74(7-8):618-623

Ecballium elaterium fruit juice is used for the treatment of sinusitis in Turkish folk medicine. The aim of this study was to increase the yield of cucurbitacin B, an anti-inflammatory compound previously isolated in various organs of E. elaterium, through tissue culture techniques. Higher yields of cucurbitacin B (1.126%) were obtained from the first subculture calluses from stem nodes in the presence of benzyl adenine (BA; 1 mg/l) and naphtalene acetic acid (NAA; 0.1 mg/l) in comparison with the yields obtained from plant material (0.01%).  相似文献   

Hydraulic architecture and water relations of a flood-tolerant tropical tree, Annona glabra     

Zotz G  Tyree MT  Patiño S 《Tree physiology》1997,17(6):359-365

Hydraulic architecture parameters, water relation parameters and wood anatomy were studied in roots and shoots of the flood-tolerant tree Annona glabra L. on Barro Colorado Island, Panama. Hydraulic conductivity, leaf specific conductivity, and Huber value were similar to the corresponding values for tree species living in non-flooded habitats. The vulnerability of stems to loss of hydraulic conductivity resulting from embolism was low (50% loss of conductivity at -3.3 MPa). The lowest leaf water potential measured in the field was about -1.0 MPa, indicating that A. glabra has a large margin of safety from embolism, which may provide protection against rare drought events, or may be an adaptation to brackish mangrove habitats. Low absolute conductivity of roots was compensated for by an increase in the number of roots. More than two-thirds of whole-plant resistance to water flow was located in the roots.  相似文献   

A new dihydroxysterol from the marine phytoplankton Diacronema sp     

Rauter AP  Filipe MM  Prata C  Noronha JP  Sampayo MA  Justino J  Bermejo J 《Fitoterapia》2005,76(5):433-438

Diacronema sp. was cultured and its sterols were separated by column chromatography on silica gel. The new sterol 24-ethyl-4alpha-methyl-cholestane-3,20-diol (1) was characterised by NMR and MS spectrometry, as well as (22E)-24-ethyl-4alpha-methyl-5alpha-cholest-22-en-3beta-ol (2) and beta-sitosterol, the major components of the sterol fractions. Neither the biosynthetic origin of the new dihydroxysterol nor its role in the biochemistry of Diacronema is known.  相似文献   

Seasonal variation of inorganic nitrogen and net mineralization in a salt marsh ecosystem   总被引：6，自引：0，他引：6  

Cartaxana  P.  Caçador  I.  Vale  C.  Falcão  M.  Catarino  F. 《Mangroves and Salt Marshes》1999,3(2):127-134

Inorganic nitrogen pools and net mineralization were estimated in three sites of a Tagus estuary salt marsh in Portugal throughout 1 year. Ammonium (NH₄ ⁺) was the major form of inorganic nitrogen found in the salt marsh soil. Extractable NH₄ ⁺ concentrations showed a marked seasonal pattern with a concentration peak during the hotter months of July/August. The great majority (>99%) of the total nitrogen in the soil was found in sedimented organic matter, not readily available for plant uptake. Net nitrogen mineralization, determined using a field incubation method, showed a peak during the months of June/July which resulted in an increase on nitrogen availability. With the exception of the lower salt marsh, estimated rates of in situ net nitrogen mineralization in the soil during summer were well related to the increase in plant aboveground biomass and plant nitrogen pools, indicating that the process is an important source of available nitrogen for plant uptake and growth. Annual net nitrogen mineralization ranged between 2.4 and 4.5gNm^–2yr^{– 1} being significantly higher for the lower salt marsh site. Rates of net nitrogen mineralization were relatively low during most of the year with a particularly active period from June to August, possibly due to an effect of temperature on soil microbial activity.  相似文献