Differences in floral morphologies affect pollination behaviour in many flowering plants. In the genus Oryza, several differences in the size of floral organs are known. In this study, we focused on the differences in...Differences in floral morphologies affect pollination behaviour in many flowering plants. In the genus Oryza, several differences in the size of floral organs are known. In this study, we focused on the differences in the size of floral organs between common cultivated rice, Oryza sativa L. and its wild ancestor, O. rufipogon. We compared floral morphologies between cultivated rice O. sativa cv. Nipponbare and O. rufipogon W630. We first evaluated temporal changes in filament and anther lengths. W630 had longer filaments with rapid elongation within 15 min after spikelet opening. W630 also had longer anthers than Nipponbare, and size of anther was consistent throughout all time examined. We also analysed other six floral traits, and found that W630 had higher stigma and style length, as well as lemma and palea length, but lower lemma and palea width. Quantitative trait locus (QTL) analysis was performed to identify the loci controlling these floral traits, using backcross recombinant inbred lines derived from a cross between Nipponbare and W630. A total of 11 significant QTLs were identified. Of these, two pairs of QTLs for lemma and palea length and one pair for lemma and palea width overlapped, suggesting that common genetic factors may be the reason for the differences in these traits. In addition, we performed QTL analysis for grain size, and found that QTLs for grain size coincided with those for lemma and palea size, indicating that grain size is partly controlled by glume capacity. The QTLs identified in this study will be informative for understanding genetic changes associated with rice domestication.展开更多
The eastern Himalayan region of Northeast （NE） India is home to a large number of indigenous rice varieties, which are traditionally classified as Oryza sativa subspecies indica, japonica or intermediate types. The ...The eastern Himalayan region of Northeast （NE） India is home to a large number of indigenous rice varieties, which are traditionally classified as Oryza sativa subspecies indica, japonica or intermediate types. The classification based on traditional Cheng’s index is often inconclusive due to phenotypic plasticity of morphological characters, which are influenced by environmental conditions. We used molecular markers specific for indica and japonica subspecies to assess the degree of genetic relatedness of indigenous rice varieties in NE India. The results revealed that majority of upland （jum） and glutinous rice varieties, traditionally considered as japonica, were genetically close to the subspecies indica. All varieties of boro ecotype were found to be indica type, and only a few varieties cultivated in lowland and upland areas were japonica type. Some of the lowland varieties of the sali ecotype were intermediate between indica and japonica, and they showed a closer genetic affinity to O. rufipogon.展开更多
Rice has been a staple food across the globe since time immemorial.Generally,different types of rice,such as white,purple,red,brown,and black rice,are named following the physical appearance of the rice bran.The color...Rice has been a staple food across the globe since time immemorial.Generally,different types of rice,such as white,purple,red,brown,and black rice,are named following the physical appearance of the rice bran.The color of the rice bran differs due to the presence of pigments in the rice varieties.Apart from general uses like cooking and fodder for cattle,rice has also been extensively involved in the field of medicine,some of which have been scientifically addressed.Although pigmented rice varieties have a history of heritage and are admired all over the world,awareness concerning the benefits of consuming these types of rice is limited.The main theme of this research article is to define the scientifically proven medicinal properties of black rice.The health properties of black rice are experimentally renowned,and gathered empirical data regarding the physiological and pharmacological activity of black rice remarkably supports the use of black rice in nutritional therapy.展开更多
文摘Differences in floral morphologies affect pollination behaviour in many flowering plants. In the genus Oryza, several differences in the size of floral organs are known. In this study, we focused on the differences in the size of floral organs between common cultivated rice, Oryza sativa L. and its wild ancestor, O. rufipogon. We compared floral morphologies between cultivated rice O. sativa cv. Nipponbare and O. rufipogon W630. We first evaluated temporal changes in filament and anther lengths. W630 had longer filaments with rapid elongation within 15 min after spikelet opening. W630 also had longer anthers than Nipponbare, and size of anther was consistent throughout all time examined. We also analysed other six floral traits, and found that W630 had higher stigma and style length, as well as lemma and palea length, but lower lemma and palea width. Quantitative trait locus (QTL) analysis was performed to identify the loci controlling these floral traits, using backcross recombinant inbred lines derived from a cross between Nipponbare and W630. A total of 11 significant QTLs were identified. Of these, two pairs of QTLs for lemma and palea length and one pair for lemma and palea width overlapped, suggesting that common genetic factors may be the reason for the differences in these traits. In addition, we performed QTL analysis for grain size, and found that QTLs for grain size coincided with those for lemma and palea size, indicating that grain size is partly controlled by glume capacity. The QTLs identified in this study will be informative for understanding genetic changes associated with rice domestication.
基金financially supported by NSERC-Canada,FRQNT and Concordia University
文摘The eastern Himalayan region of Northeast （NE） India is home to a large number of indigenous rice varieties, which are traditionally classified as Oryza sativa subspecies indica, japonica or intermediate types. The classification based on traditional Cheng’s index is often inconclusive due to phenotypic plasticity of morphological characters, which are influenced by environmental conditions. We used molecular markers specific for indica and japonica subspecies to assess the degree of genetic relatedness of indigenous rice varieties in NE India. The results revealed that majority of upland （jum） and glutinous rice varieties, traditionally considered as japonica, were genetically close to the subspecies indica. All varieties of boro ecotype were found to be indica type, and only a few varieties cultivated in lowland and upland areas were japonica type. Some of the lowland varieties of the sali ecotype were intermediate between indica and japonica, and they showed a closer genetic affinity to O. rufipogon.
基金Department of Science and Technology, Government of India, for providing INSPIRE Fellowshipauthorities of Annamalai University for providing necessary support
文摘Rice has been a staple food across the globe since time immemorial.Generally,different types of rice,such as white,purple,red,brown,and black rice,are named following the physical appearance of the rice bran.The color of the rice bran differs due to the presence of pigments in the rice varieties.Apart from general uses like cooking and fodder for cattle,rice has also been extensively involved in the field of medicine,some of which have been scientifically addressed.Although pigmented rice varieties have a history of heritage and are admired all over the world,awareness concerning the benefits of consuming these types of rice is limited.The main theme of this research article is to define the scientifically proven medicinal properties of black rice.The health properties of black rice are experimentally renowned,and gathered empirical data regarding the physiological and pharmacological activity of black rice remarkably supports the use of black rice in nutritional therapy.
