Rice (Oryza sativa L.) is a short-day plant. Long-day condition can prevent or considerably delay its flowering time. Photoperiod sensitive rice can grow only in rainy season. When growing in dry season (light over 12 hours/day), its flowering time is delayed but non-photoperiod senssitive rice can grow in all seasons of the year. Studies on quantitative trait loci (QTLs) showed that photoperiod sensitive rice was found to be controlled by six loci: Hd1, Hd2, Hd3a, Hd5 and Hd6; with Hd1 as the major gene. The Hd1 allele is a photosensitive functional allele and works in long-day lengths by delaying inflorescence while hd1 allele is a non-photosensitive non-functional allele and works in short-day lengths by promoting inflorescence. Besides, plant height is one of the most important traits of rice cultivar in relation to the falling down or resistance effect of environmental conditions such as wind and rain. Tall plants are easy to be down or break when they are exposed to wind and rain thus reducing 25% of grain yield, while short plants can resist wind and rain. Plant height in rice is found to be controlled by the gene Sd1/sd1 with Sd1 gene for tallness and sd1 gene for semi-dwarfness. On the other hand, presence of endosperm amylose is one of the most important traits of rice cultivar that determine qualities of rice grain. Rice endosperm was found to be controlled by Wx/wx gene with glutinous phenotypes controlled by single recessive gene, wx and non-glutinous phenotypes controlled by dominant gene, Wx. One of the developments in rice biotechnology was the advent of molecular markers. In rice breeding, mole ocular markers assisted backcrossing (MAB) was applied widely mu ch recently. The use of MAB will help rice breeders to save time, efficiency and accuracy in selecting complex traits. RD 15 is a non-glutinous rice variety with good cooking qualities. However, the plant is tall and photoperiod sensitive hence it can only planted during the wet season and can be blown down. That is why the aim of this research is to use molecular markers assisted backcrossing
Rice (Oryza sativa L.) is a short-day plant. Long-day condition can prevent or considerably delay its flowering time. Photoperiod sensitive rice can grow only in rainy season. When growing in dry season (light over 12 hours/day), its flowering time is delayed but non-photoperiod senssitive rice can grow in all seasons of the year. Studies on quantitative trait loci (QTLs) showed that photoperiod sensitive rice was found to be controlled by six loci: Hd1, Hd2, Hd3a, Hd5 and Hd6; with Hd1 as the major gene. The Hd1 allele is a photosensitive functional allele and works in long-day lengths by delaying inflorescence while hd1 allele is a non-photosensitive non-functional allele and works in short-day lengths by promoting inflorescence. Besides, plant height is one of the most important traits of rice cultivar in relation to the falling down or resistance effect of environmental conditions such as wind and rain. Tall plants are easy to be down or break when they are exposed to wind and rain thus reducing 25% of grain yield, while short plants can resist wind and rain. Plant height in rice is found to be controlled by the gene Sd1/sd1 with Sd1 gene for tallness and sd1 gene for semi-dwarfness. On the other hand, presence of endosperm amylose is one of the most important traits of rice cultivar that determine qualities of rice grain. Rice endosperm was found to be controlled by Wx/wx gene with glutinous phenotypes controlled by single recessive gene, wx and non-glutinous phenotypes controlled by dominant gene, Wx. One of the developments in rice biotechnology was the advent of molecular markers. In rice breeding, mole ocular markers assisted backcrossing (MAB) was applied widely mu ch recently. The use of MAB will help rice breeders to save time, efficiency and accuracy in selecting complex traits. RD 15 is a non-glutinous rice variety with good cooking qualities. However, the plant is tall and photoperiod sensitive hence it can only planted during the wet season and can be blown down. That is why the aim of this research is to use molecular markers assisted backcrossing
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