In this paper,the quantitative relationship between the wild fruit communities and direct environmental factors is discussed on the basis of detailed data on landscape scale habitats obtained through field vegetation ...In this paper,the quantitative relationship between the wild fruit communities and direct environmental factors is discussed on the basis of detailed data on landscape scale habitats obtained through field vegetation investigation.The results from TWINSPAN and DCCA showed that:1) In the distribution sections of the wild fruit forest in the Keguqin Mountain region,the basic patterns characteristic of the different habitats are due to topographic factors,nutrients and moisture conditions;2) The elevation affected the most basic differentiation of plant communities in the study area,indicating that the elevation condition was the most important factor restricting the distribution of the wild fruit communities in the study area;3) The close relationship between the moisture content in the upper soil layer and the elevation reflected the influence of moisture conditions on both wild fruit and herb-layer communities;4) Nutrient differences not only indicated that the habitat conditions were different in themselves but also showed that the present nutrient conditions of the habitats were seriously affected by human activities.In summary,under complicated mountainous topographic conditions,the habitat conditions for the communities differed very significantly,and the combination of elevation,soil moisture content,total nitrogen,slope aspect,and pH value influenced and controlled the formation of community distribution patterns in the study area.展开更多
Malaysian Agriculture Research and Development Institute （MARDI） is the country＇s major custodian of the nation＇s crops genetic resources. It has a global responsibility in the conservation of genetic resources of...Malaysian Agriculture Research and Development Institute （MARDI） is the country＇s major custodian of the nation＇s crops genetic resources. It has a global responsibility in the conservation of genetic resources of banana, sweet potato and citrus, and national responsibility for the conservation of crops, such as rice, tropical fruits and some herbs and medicinal plant species. MARDI rice seed genebank at Seberang Prai in the state of Penang was established in 1984 and currently holds 12,770 registered rice accessions, of which 53% are of local origin. In addition, MARDI also conserves genes in the field, mostly for underutilized tropical fruit genetic resources. At present, about 168 species of underutilized, rare and wild tropical fruit species consisting of about 2,000 accessions, the largest in the country, are being conserved. The species include ＂kuini＂ （Mangifera odorata）, ＂bacang＂ （Mangifera foetida）, ＂binjai＂ （Mangifera caesia）, ＂cerapu＂ （ Garcinia praniana）, ＂rambai＂ （Baccaurea motleyana）, ＂asam gelugor＂ （ Garcinia atroviridis）, ＂terap＂ （drthocarpus odoratissimus） and ＂pulasan＂ （Nephellium rambutan-ake）. The accessions are mostly conserved ex situ in field genebanks located at the various MARDI stations throughout the country. Although the conservation of the various crop species genetic resources is important, the real challenge is enhancing its utilisation. The main objective of the paper was to share and disseminate information related to works conducted and strategies opted by MARDI on the conservation and utilization of crop genetic resources. Information on species of crops that are available in MARDI＇s genebank was also highlighted together with brief information of some of the associated traits of significant importance posses by those genetic resources.展开更多
In this study,strontium adsorption from sulfuric acid solution by different Dowex 50W-X ion exchange resins was investigated.Among these resins,Dowex 50W-X8 resin showed the maximum sorption of strontium from the aque...In this study,strontium adsorption from sulfuric acid solution by different Dowex 50W-X ion exchange resins was investigated.Among these resins,Dowex 50W-X8 resin showed the maximum sorption of strontium from the aqueous solutions.The effect of pH,contact time,mass of resin,temperature,and concentration of interfering ions on strontium adsorption were evaluated to determine the optimum conditions of strontium sorption process.The kinetic models of sorption were analyzed using pseudo-first and pseudo-second order models.The results indicated that the pseudo-second order kinetic model was more appropriate than the other one.Moreover,the data obtained in this study were fitted into several sorption isotherm models and it was found that the Langmuir sorption isotherm shows the best fitting to the experimental data.展开更多
In order to maintain the health and vigour and to sustain the productivity, a pruning experiment was conducted on four year old ＂Balwant＂ cultivar of aonla grown in laterite soil, planted at a spacing of 5m×5m....In order to maintain the health and vigour and to sustain the productivity, a pruning experiment was conducted on four year old ＂Balwant＂ cultivar of aonla grown in laterite soil, planted at a spacing of 5m×5m. To find out the best pruning method, six levels of pruning was performed i.e., （1） Light judicious pruning, （2） Detopping of primary branches at 8 feet from ground level ＋ removal of all secondary branches, （3） Detopping of primary branches at 8 feet from the ground level ＋ removal of all secondary branches at 2 feet from the base of primary branches, （4） Detopping of primary branches at 8 feet from the ground level ＋ removal of all secondary branches at 1 feet from the base of primary branches, （5） Light judicious pruning ＋ Detopping of plant canopy of at 8 feet from the ground level, （6） No pruning （control）. Results of three consecutive years of investigation revealed that light judicious pruning of thin, overlapping, criss-crossed, dead, unproductive and looping branches gave highest fruit yield in all the three years and resulted 64.4 percent yield increment over control when average of three years was considered. Severe pruning of primary and secondary branches caused drastic reduction of yield for two consecutive years after pruning. Judicious pruning helped to produce better sizeable and quality fruits.展开更多
基金National Technology Support Program (Grant Nos. 2007BAC17B06,2007BAC16B06,2006BAD26B0901)National Natural Science Foundation(Grant Nos. 31060062,110140101)
文摘In this paper,the quantitative relationship between the wild fruit communities and direct environmental factors is discussed on the basis of detailed data on landscape scale habitats obtained through field vegetation investigation.The results from TWINSPAN and DCCA showed that:1) In the distribution sections of the wild fruit forest in the Keguqin Mountain region,the basic patterns characteristic of the different habitats are due to topographic factors,nutrients and moisture conditions;2) The elevation affected the most basic differentiation of plant communities in the study area,indicating that the elevation condition was the most important factor restricting the distribution of the wild fruit communities in the study area;3) The close relationship between the moisture content in the upper soil layer and the elevation reflected the influence of moisture conditions on both wild fruit and herb-layer communities;4) Nutrient differences not only indicated that the habitat conditions were different in themselves but also showed that the present nutrient conditions of the habitats were seriously affected by human activities.In summary,under complicated mountainous topographic conditions,the habitat conditions for the communities differed very significantly,and the combination of elevation,soil moisture content,total nitrogen,slope aspect,and pH value influenced and controlled the formation of community distribution patterns in the study area.
文摘Malaysian Agriculture Research and Development Institute （MARDI） is the country＇s major custodian of the nation＇s crops genetic resources. It has a global responsibility in the conservation of genetic resources of banana, sweet potato and citrus, and national responsibility for the conservation of crops, such as rice, tropical fruits and some herbs and medicinal plant species. MARDI rice seed genebank at Seberang Prai in the state of Penang was established in 1984 and currently holds 12,770 registered rice accessions, of which 53% are of local origin. In addition, MARDI also conserves genes in the field, mostly for underutilized tropical fruit genetic resources. At present, about 168 species of underutilized, rare and wild tropical fruit species consisting of about 2,000 accessions, the largest in the country, are being conserved. The species include ＂kuini＂ （Mangifera odorata）, ＂bacang＂ （Mangifera foetida）, ＂binjai＂ （Mangifera caesia）, ＂cerapu＂ （ Garcinia praniana）, ＂rambai＂ （Baccaurea motleyana）, ＂asam gelugor＂ （ Garcinia atroviridis）, ＂terap＂ （drthocarpus odoratissimus） and ＂pulasan＂ （Nephellium rambutan-ake）. The accessions are mostly conserved ex situ in field genebanks located at the various MARDI stations throughout the country. Although the conservation of the various crop species genetic resources is important, the real challenge is enhancing its utilisation. The main objective of the paper was to share and disseminate information related to works conducted and strategies opted by MARDI on the conservation and utilization of crop genetic resources. Information on species of crops that are available in MARDI＇s genebank was also highlighted together with brief information of some of the associated traits of significant importance posses by those genetic resources.
文摘In this study,strontium adsorption from sulfuric acid solution by different Dowex 50W-X ion exchange resins was investigated.Among these resins,Dowex 50W-X8 resin showed the maximum sorption of strontium from the aqueous solutions.The effect of pH,contact time,mass of resin,temperature,and concentration of interfering ions on strontium adsorption were evaluated to determine the optimum conditions of strontium sorption process.The kinetic models of sorption were analyzed using pseudo-first and pseudo-second order models.The results indicated that the pseudo-second order kinetic model was more appropriate than the other one.Moreover,the data obtained in this study were fitted into several sorption isotherm models and it was found that the Langmuir sorption isotherm shows the best fitting to the experimental data.
文摘In order to maintain the health and vigour and to sustain the productivity, a pruning experiment was conducted on four year old ＂Balwant＂ cultivar of aonla grown in laterite soil, planted at a spacing of 5m×5m. To find out the best pruning method, six levels of pruning was performed i.e., （1） Light judicious pruning, （2） Detopping of primary branches at 8 feet from ground level ＋ removal of all secondary branches, （3） Detopping of primary branches at 8 feet from the ground level ＋ removal of all secondary branches at 2 feet from the base of primary branches, （4） Detopping of primary branches at 8 feet from the ground level ＋ removal of all secondary branches at 1 feet from the base of primary branches, （5） Light judicious pruning ＋ Detopping of plant canopy of at 8 feet from the ground level, （6） No pruning （control）. Results of three consecutive years of investigation revealed that light judicious pruning of thin, overlapping, criss-crossed, dead, unproductive and looping branches gave highest fruit yield in all the three years and resulted 64.4 percent yield increment over control when average of three years was considered. Severe pruning of primary and secondary branches caused drastic reduction of yield for two consecutive years after pruning. Judicious pruning helped to produce better sizeable and quality fruits.
