Single nucleotide polymorphisms and restriction digestion-based haplotype variations among 160 flood prone rice varieties were analyzed with enzymes Alu I and Cac8 I to generate polymorphisms at Sub1A and Sub1C loci ...Single nucleotide polymorphisms and restriction digestion-based haplotype variations among 160 flood prone rice varieties were analyzed with enzymes Alu I and Cac8 I to generate polymorphisms at Sub1A and Sub1C loci （conferring submergence tolerance）, respectively. Haplotype associated with phenotype was used to study the haplotype variations at Sub1A and Sub1C loci and to determine their functional influence on submergence tolerance and stem elongation. Three patterns at Sub1A locus, Sub1A0 （null allele）, Sub1A1 （does not cut） and Sub1A2 （one SNP）, and four patterns at Sub1C locus, Sub1C1, Sub1C2, Sub1C3 and Sub1C4, were generated. Both tolerant Sub1A1 and intolerant Sub1A2 had the same length, but the difference was presence of a restriction site in the Sub1A2, but absent at the Sub1A1. Further, two types of polymorphism were detected at the Sub1C, one included major length polymorphisms （165, 170 and 175 bp） and the other was a single restriction site at different position. Eight haplotypes （different combinations of the two loci）, A1C1, A1C2, A1C4, A2C2, A2C4, A0C2, A0C3 and A0C4, were detected among 160 varieties. Haplotype A1C1 was comparatively more related to haplotypes A1C2 and A1C4, having the same Sub1A allele, and these haplotypes were found only in Bangladeshi, Sri Lankan and Indian varieties. Most tolerant varieties in A1C1 haplotype showed slow elongation, having tolerant specific Sub1A1 and Sub1C1 alleles. Further, the varieties Madabaru and Kottamali （A2C2） also showed moderate level of tolerance without Sub1A1 allele. These varieties were different with FR13A and also suspected to carry different novel tolerant genes at other loci. These materials could be used for hybridization with Sub1 varieties for pyramiding additional tolerant specific alleles into a single genotype for improving submergence tolerance in rice.展开更多
Conventional power generation mainly depends on natural gas and diesel oil in Brunei Darussalam.The power utility company is now thinking of power generation using natural wind.In this paper,wind energy,being one of t...Conventional power generation mainly depends on natural gas and diesel oil in Brunei Darussalam.The power utility company is now thinking of power generation using natural wind.In this paper,wind energy,being one of the most readily available renewable energy sources,was studied.The wind characteristic,velocity and directions were studied using Weibull distribution based on the measurement of wind speed at two different locations in Brunei Darussalam.These wind speed distributions were modeled using the Wind Power program.The wind rose graph was obtained for the wind direction to analyze the wind power density onshore and offshore.Based on this analysis,it has been found that the wind speed of 3 to 5m/s has a probability of occurrence of 40%.Besides,the annual energy production at a wind speed of 5m/s has been found to be in the range between 1000 and 1500 kWh for both the locations in Brunei Darussalam.展开更多
文摘Single nucleotide polymorphisms and restriction digestion-based haplotype variations among 160 flood prone rice varieties were analyzed with enzymes Alu I and Cac8 I to generate polymorphisms at Sub1A and Sub1C loci （conferring submergence tolerance）, respectively. Haplotype associated with phenotype was used to study the haplotype variations at Sub1A and Sub1C loci and to determine their functional influence on submergence tolerance and stem elongation. Three patterns at Sub1A locus, Sub1A0 （null allele）, Sub1A1 （does not cut） and Sub1A2 （one SNP）, and four patterns at Sub1C locus, Sub1C1, Sub1C2, Sub1C3 and Sub1C4, were generated. Both tolerant Sub1A1 and intolerant Sub1A2 had the same length, but the difference was presence of a restriction site in the Sub1A2, but absent at the Sub1A1. Further, two types of polymorphism were detected at the Sub1C, one included major length polymorphisms （165, 170 and 175 bp） and the other was a single restriction site at different position. Eight haplotypes （different combinations of the two loci）, A1C1, A1C2, A1C4, A2C2, A2C4, A0C2, A0C3 and A0C4, were detected among 160 varieties. Haplotype A1C1 was comparatively more related to haplotypes A1C2 and A1C4, having the same Sub1A allele, and these haplotypes were found only in Bangladeshi, Sri Lankan and Indian varieties. Most tolerant varieties in A1C1 haplotype showed slow elongation, having tolerant specific Sub1A1 and Sub1C1 alleles. Further, the varieties Madabaru and Kottamali （A2C2） also showed moderate level of tolerance without Sub1A1 allele. These varieties were different with FR13A and also suspected to carry different novel tolerant genes at other loci. These materials could be used for hybridization with Sub1 varieties for pyramiding additional tolerant specific alleles into a single genotype for improving submergence tolerance in rice.
文摘Conventional power generation mainly depends on natural gas and diesel oil in Brunei Darussalam.The power utility company is now thinking of power generation using natural wind.In this paper,wind energy,being one of the most readily available renewable energy sources,was studied.The wind characteristic,velocity and directions were studied using Weibull distribution based on the measurement of wind speed at two different locations in Brunei Darussalam.These wind speed distributions were modeled using the Wind Power program.The wind rose graph was obtained for the wind direction to analyze the wind power density onshore and offshore.Based on this analysis,it has been found that the wind speed of 3 to 5m/s has a probability of occurrence of 40%.Besides,the annual energy production at a wind speed of 5m/s has been found to be in the range between 1000 and 1500 kWh for both the locations in Brunei Darussalam.
