Demerium exchange of hydroxyl groups in allophane

The nature of amorphous silicates, allophane,ö The name allophane is used in this paper in a dual sense; the one stands for a group of amorphous or nearly amorphous aluminum silicates associated with minor amounts of other metals, and the other in some restricted sense for amorphous silicates other than imogolite. The latter term, imogolite, is used for convenience to denote a component that shows broad x-ray diffractions at 14 (strong), 7.6 (medium) and 5.6 (weak) Å, gives an endotherm at 430°C, and appears as thread-like particles of diameter 100 to 200 Å in electronmicrographs (21). as a main clay constituent determines many of the physical and chemical properties of volcanic ash soils. Recent developments in the study of allophane together with other amorphous inorganic materials in relation to their nature and occurrence in soils have been reviewed by MITCHELL et al. (12).     

Factors Influencing the Determination of Microbial Biomass-Nitrogen in Submerged Soil

In a previous paper (1), a modification of the chloroform fumigation method (2) was proposed for estimating microbial biomass-nitrogen (N) in submerged soil. It was found that a large part of the living bacteria in the submerged soil was killed within about 12 h of the fumigation and was actively mineralized by subsequent anaerobic incubation.

In this paper, the following factors which influence the estimated amount of microbial biomass-N were examined: a) inoculation to fumigated soil, b) duration of anaerobic incubation, c) storage and sieving pretreatments of soil, and d) effect of fumigation on soil organic matter.     

Comparison of Salmonella enterica serovar Abortusequi isolates of equine origin by pulsed-field gel electrophoresis and fluorescent amplified-fragment length polymorphism fingerprinting

Equine paratyphoid is caused by Salmonella enterica serovar Abortusequi, and manifests mainly as abortion in the mare. We compared S. Abortusequi strains isolated in Japan and other countries using pulsed-field gel electrophoresis (PFGE) and fluorescent amplified-fragment length polymorphism (FAFLP) analysis. PFGE analysis of S. Abortusequi strains gave 21-27 fragments ranging in size from 33 to 602kb. Although two PFGE profiles were observed among the 20 S. Abortusequi isolates in Japan, the restriction fragments originating from the chromosome were common between the two profiles. The similarity index of the two profiles was 90.9%, while those between Japanese and five other S. Abortusequi strains were 29.8-37.5%. On the other hand, FAFLP analysis of S. Abortusequi strains generated 64-67 amplified fragments ranging in size from 100 to 400bp. One polymorphic fragment was observed among the 20 S. Abortusequi isolates in Japan. These data indicate the close relation of this agent in Japan. S. Abortusequi strains sharing a common ancestry might have been conserved in Japan.     

Screening for new sources of resistance to Clavibacter michiganensis subsp. michiganensis (Cmm) in tomato

Bacterial canker of tomato, caused by Clavibacter michiganensis subsp. michiganensis (Cmm), is considered the most serious bacterial threat, resulting in high damages in production areas. Worldwide, Cmm is subjected to quarantine regulations.There is no cultivar in market containing Cmm resistance genes. This project aimed to screen tomatoes or wild relatives of tomato for resistance to Cmm, to be used for starting breeding programs. We have screened 24 different wild accessions of tomato and found several new tolerant sources: Solanum pimpinellifolium GI.1554, S. parviflorum LA735 and S. parviflorum LA2072. We also confirmed the tolerance which was reported previously in S. peruvianum LA2157, S. peruvianum PI127829, S. peruvianum LA385, S. habrochaites LA407 and S. lycopersicum cv. IRAT L3. No immunity was found. Also accessions showing a low disease score still contained high titers of bacteria as determined by a dilution plating method, using tow selective media. These results were confirmed with a TaqMan real time PCR assay, which was developed to determine and quantify Cmm in planta.     

Occurrence and distribution of settling and newly settled spotted halibut Verasper variegatus and Japanese flounder Paralichthys olivaceus in shallow nursery grounds around Shimabara Peninsula, western Japan

The occurrence and distribution of settling and settled spotted halibut Verasper variegatus were compared with those of Japanese flounder Paralichthys olivaceus in shallow habitats around Shimabara Peninsula, western Japan, to elucidate the settlement and recruitment characteristics of spotted halibut, a rare pleuronectid flatfish in Japan. Push-net sampling conducted at nine sites in March and April 2003 collected spotted halibut from four nurseries located at eastern areas of Shimabara Peninsula in Ariake Bay; Japanese flounder were sampled from eight nurseries. Comparison of microhabitat distributions in a tidal-flat nursery during February?CApril in 2003?C2007 revealed that metamorphosing larvae and juveniles of spotted halibut, which showed the drastic body coloration (black to brown) and behavioral changes (frequent swimming to settlement), were distributed mainly in the lower edge of the intertidal area, whereas Japanese flounder inhabited both intertidal and subtidal areas. Metamorphosing larvae of spotted halibut (12.6?C16.5?mm standard length; n?=?24) were collected in March when the highest densities were observed, whereas metamorphosing larvae of Japanese flounder (10.0?C15.9?mm, n?=?55) were observed during March?CApril. Our results suggest that spotted halibut has a narrower time/space window for recruitment to the specific nurseries compared with Japanese flounder.     

The effect of seaweed extracts,as a supplement or alternative culture medium,on the growth rate and biochemical composition of the microalga,Isochrysis galbana (Park 1949)

Aqueous extracts of green [Ulva lactuca Linnaeus and Enteromorpha intestinalis (Linnaeus) Nees] and red [Gracilaria corticata (J. Agardh) J. Agardh] seaweeds from the Persian Gulf of Iran were examined for their potential usefulness as components of microalga Isochrysis galbana culture medium against conventional f/2 medium. Isochrysis galbana was successfully cultured using the tested seaweed extracts (SWE) and exhibited higher or similar cell density and biomass when SWE were used as a supplement or an alternative medium respectively. When the SWE were used as an alternative medium, microalgal protein, lipid and ash content were similar but carbohydrate increased compared with control. Total saturated fatty acids decreased with a corresponding increase in total mono‐ and polyunsaturated fatty acids following supplementation of f/2 medium with SWE. Eicosapentaenoic acid (EPA) was not affected by SWE treatments but docosahexaenoic acid (DHA) tended to decrease, except for I. galbana cultured with U. lactuca extract. With the exception of potassium, SWE did not significantly impact the mineral content of cultured I. galbana. The study points to the potential usefulness of specific SWE in the production of microalgae as a food source in aquaculture.     

Maize-rice cropping systems in Bangladesh： Status and research needs

Maize-rice cropping systems are expanding in Bangladesh. Hybrid maize has increasing demand and value, particularly for poultry feed, while rice remains the traditional dominant starch staple food. Bangladesh maize yields （with average farm yields around 5.7 t·ha^-1） are among the highest found in Asia. Cool winter （Rabi） season maize followed by T. Aman （monsoon） rice is the major cropping system; however it is now becoming diversified with many other crops including potato. Financially, hybrid maize is far more profitable than boro （irrigated） rice, wheat, or most other competing winter season Rabi crops. Although maize is relatively problem-free in Bangladesh, some constraints are intensifying with increased concern over input supply and soil-related environmental sustainability. An array of new technologies for sustainable intensive maize production systems is emerging in Bangladesh and some are being promoted and adopted. Continued sustainability of hybrid maize production in Bangladesh depends on optimization of planting time, quality seed of appropriate hybrids, balanced use of nutrient inputs along with soil fertility conservation and other management, for which further research would be high priority.     

The oak gallwasp <Emphasis Type="Italic">Aphelonyx persica:</Emphasis> a new record from Turkey,with some new host records

A new record is reported of the oak gallwasp Aphelonyx persica on oaks (Quercus cerris, Q. ithaburensis, Q. trojana) in the Inland Aegean Region of Turkey. This species is recorded for the first time on Q. cerris and Q. trojana. Details are given of the geographical distribution, hosts and phenology.     

Development of EST-SSR markers and construction of a linkage map in faba bean (Vicia faba)

To develop a high density linkage map in faba bean, a total of 1,363 FBES (Faba bean expressed sequence tag [EST]-derived simple sequence repeat [SSR]) markers were designed based on 5,090 non-redundant ESTs developed in this study. A total of 109 plants of a ‘Nubaria 2’ × ‘Misr 3’ F₂ mapping population were used for map construction. Because the parents were not pure homozygous lines, the 109 F₂ plants were divided into three subpopulations according to the original F₁ plants. Linkage groups (LGs) generated in each subpopulation were integrated by commonly mapped markers. The integrated ‘Nubaria 2’ × ‘Misr 3’ map consisted of six LGs, representing a total length of 684.7 cM, with 552 loci. Of the mapped loci, 47% were generated from multi-loci diagnostic (MLD) markers. Alignment of homologous sequence pairs along each linkage group revealed obvious syntenic relationships between LGs in faba bean and the genomes of two model legumes, Lotus japonicus and Medicago truncatula. In a polymorphic analysis with ten Egyptian faba bean varieties, 78.9% (384/487) of the FBES markers showed polymorphisms. Along with the EST-SSR markers, the dense map developed in this study is expected to accelerate marker assisted breeding in faba bean.