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941.
Meike Piepenbring 《Mycological Progress》2005,4(2):161-166
Sphaerophragmium pulchrum is proposed as a new microcyclic rust species on Albizia adinocephala from Panama. Telia and spermogonia are described, illustrated, and compared to those of known species of Sphaerophragmium. Spermogonia are described for the first time for a species of Sphaerophragmium. This is the first record of this genus for the southern part of the Central American isthmus. 相似文献
942.
Peter W. Inglis Rubia B. C. Sarmento Camila F. C. Gavião M. Cléria Valadares-Inglis 《World journal of microbiology & biotechnology》2005,21(8-9):1487-1492
Summary Telomeric fingerprinting was found to be highly differentiating for Paecilomyces fumosoroseus and Paecilomyces lilacinus isolates in comparison to intron splice site PCR and is therefore a good method for quality control of future products based
on these fungi. Although the telomeric restriction length polymorphisms correctly divided the isolates into their appropriate
species, further correlation with host range or geographical origin of the isolates was not found. In this respect, intron
splice site PCR was more informative taxonomically. The chromosome numbers inferred from telomeric fingerprints were seven
chromosomes for P. lilacinus and between six and nine chromosomes for P. fumosoroseus. 相似文献
943.
Panlada Tittabutr Waraporn Payakapong Neung Teaumroong Nantakorn Boonkerd 《World journal of microbiology & biotechnology》2005,21(6-7):823-829
Summary The aim of this research was to develop methods to use low-cost carbon compounds for rhizobial inoculant production. Five
raw starch materials; steamed cassava, sticky rice, fresh corn, dry corn and sorghum were tested for sugar production by an
amylase-producing fungus. Streamed cassava produced the highest amount of reducing sugar after fermentation. Bradyrhizobium japonicum USDA110, Azorhizobium caulinodans IRBG23, Rhizobium phaseoli TAL1383, Sinorhizobium fredii HH103, and Mesorhizobium ciceri USDA2429 were tested on minimal medium supplemented with reducing sugar obtained from cassava fermentation. All strains,
except B. japonicum USDA110, could grow in medium containing cassava sugar derived from 100 g steamed cassava per litre, and the growth rates
for these strains were similar to those in medium containing 0.5 (w/v) mannitol. The sugar derived from steamed cassava was
further used for production of glycerol using yeast. After 1 day of yeast fermentation, the culture containing glycerol and
heat-killed yeast cells, was used to formulate media for culturing bradyrhizobia. A formulation medium, FM4, with a glycerol
concentration of 0.6 g/l and yeast cells (OD600 = 0.1) supported growth of B. japonicum USDA110 up to 3.61 × 109 c.f.u./ml in 7 days. These results demonstrate that steamed cassava could be used to provide cheap and effective carbon sources
for rhizobial inoculant production. 相似文献
944.
植物内生固氮菌研究进展 总被引:2,自引:0,他引:2
综述了植物内生固氮菌生物多样性、生物学特性 ,生理特性 ,与寄主植物的相互作用及应用前景等方面的研究进展。 相似文献
945.
云南重楼植物内生真菌的分离及抗菌活性筛选 总被引:8,自引:1,他引:7
从云南重楼[Paris polyphylla Smithvar.yunnnanensis(Franch.)Hand.Mazz.]块状茎中分离出166株内生真菌,对其进行形态分类鉴定归于4目,6科,20个属,体现了云南重楼植物内生真菌的生物多样性特征。同时,选择与人类和植物相关的37株病原微生物作为抗菌活性筛选指示菌,进行了云南重楼植物内生真菌抗菌活性的初步研究。结果表明,4株内生真菌对细菌、植物致病真菌、皮肤致病真菌多种病原微生物具有显著抑制生长的作用。 相似文献
946.
947.
948.
Photosynthesis and water efflux were measured in different PAR and stomatal conductance in members of Avicenniaceae and Rhizophoraceae.
Trend of leaf temperature with irradiance and its effect on photosynthesis were also estimated. In most of the studied species,
photosynthesis and stomatal conductance followed similar trends with increase in irradiance. The rate of net photosynthesis
and stomatal conductance were higher in members of Avicenniaceae than in Rhizophoraceae. In Avicenniaceae, the optimum PAR
for maximum photosynthesis ranged between 1340–1685 (μmol m-2s-1, which was also higher than that of Rhizophoraceae (840-1557 μmol m-2s-1). Almost in all the studied taxa, transpiration and stomatal conductance followed similar trends and reached the maximal
peaks at the same PAR value. The range of breakeven leaf temperature was almost the same in both the families (34-36°C in
Avicenniaceae and 33.5-36.3°C in Rhizophoraceae), beyond which assimilation rate declined. 相似文献
949.
Plant-mediated methane emission from an Indian mangrove 总被引:3,自引:0,他引:3
Ramachandran Purvaja Ramachandran Ramesh Peter Frenzel† 《Global Change Biology》2004,10(11):1825-1834
Mangroves have been considered for a long time to be a minor methane source, but recent reports have shown that polluted mangroves may emit substantial amounts of methane. In an unpolluted Indian mangrove, we measured annual methane emission rates of 10 g CH4 yr?1 from the stands of Avicennia marina. This rate is of the same order of magnitude as rates from Northern wetlands. Methane emission from a freshwater‐influenced area was higher, but was lower from a stunted mangrove growing on a hypersaline soil. Methane emission was mediated by the pneumatophores of Avicennia. This was consistent with the methane concentration in the aerenchyma, which decreased on average from 350 ppmv in the cable roots to 10 ppmv in the emergent part of the pneumatophores. However, the number of pneumatophores varied seasonally. The minimum number occurred during the monsoon season, which reduced methane emissions largely. Ebullition from unvegetated areas may also be important, at least during monsoon season when measured bubble fluxes were occasionally about five times as high as pneumatophore‐mediated emissions. 相似文献
950.