In plants,a large number of anthocyanin biosynthetic genes encoding enzymes and regulatory genes encoding transcription factors are required for anthocyanin synthesis.Coleoptile purple lines are two purple lines on bo...In plants,a large number of anthocyanin biosynthetic genes encoding enzymes and regulatory genes encoding transcription factors are required for anthocyanin synthesis.Coleoptile purple lines are two purple lines on both sides of coleoptiles after seed germination.However,the molecular mechanism of coleoptile purple line is not clear in rice so far.In this study,two major dominant genes,coleoptile purple line 1(OsCPL1,also known as OsC1)and coleoptile purple line 2(OsCPL2),were isolated via map-based cloning,and both of them were required for anthocyanin biosynthesis of coleoptile purple line in rice.The knockout and complementation experiments confirmed that OsC1 was required for purple color in most organs,such as coleoptile line,sheath,auricle,stigma and apiculus,whereas OsCPL2 was just required for coleoptile purple line.OsC1 was predominantly expressed in coleoptiles,flag leaves,and green panicles,and highly expressed in young leaves,whereas OsCPL2 was predominantly expressed in coleoptiles,and extremely lowly expressed in the other tested organs.Loss-of-function of either OsC1 or OsCPL2 resulted in significant reduction of transcript levels of multiple anthocyanin biosynthesis genes in coleoptiles.Coleoptile purple line was further used as a marker trait in hybrid rice.Purity identification in hybrid rice seeds via coleoptile purple line just needed a little water,soil and a small plate and could be completed within 5 d.Molecular marker and field identification analyses indicated that coleoptile purple line was reliable for the hybrid seed purity identification.Our findings disclosed that coleoptile purple line in rice was regulated by two major dominant genes,OsC1 and OsCPL2,and can be used as a simple,rapid,accurate and economic marker trait for seed purity identification in hybrid rice.展开更多
The seed samples of Yuetai A, a Honglian （HL） type cytoplasmic male sterile （CMS） line in hybrid rice were investigated to assess the seed purity and to analyze the cause of off-type plants by imitating the biolog...The seed samples of Yuetai A, a Honglian （HL） type cytoplasmic male sterile （CMS） line in hybrid rice were investigated to assess the seed purity and to analyze the cause of off-type plants by imitating the biological contaminant to Yuetai A in Nanjing, Jiangsu Province and Lingshui, Hainan Province during 2004-2006. The seed impurity of Yuetai A mainly resulted from the genetic drift of restoring fertility gene （Rt） after biological contamination but not from its sterility unstability. All of the ten maintainer lines, five restorer lines and three thermo-sensitive genic male sterile lines used in the study could pollinate Yuetai A and Yuetai B to produce F1 plants, directly or indirectly resulting in Rf-gene drifting into Yuetai A and generating ＇iso-cytoplasm restoring-generations＇. Furthermore, high outcrossing rate and similar heading date of Yuetai A with many varieties used in rice production might easily result in the biological contamination. After removing all plants with Rf-gene mixed in Yuetai A and preventing Rf-gene drifting into Yuetai A, the seed purity of Yuetai A and Yuetai B had been raised to 100%.展开更多
Different results of seed purity identification for Gangyou 158, Ⅱ You 808, Wuyou 308 and Tianfengyou 316 were obtained using different SSR primers in our early work. To find out the reasons, the four hybrid combinat...Different results of seed purity identification for Gangyou 158, Ⅱ You 808, Wuyou 308 and Tianfengyou 316 were obtained using different SSR primers in our early work. To find out the reasons, the four hybrid combinations were grown in field to identify their purity according to their phenotypic traits. Then, the results of field identification were compared with that of laboratory tests using different SSR primers. The comparison revealed that only sterile lines （female parent） were distin- guished from true hybrids using the primers RM208, RM264, RM242 and RM164 for the purity identification of Gangyou 158, II You 808, Wuyou 308 and Tianfengyou 316, so the results were higher than that of field identification. In contrast, the primers RM341, RM297, RM21 and RM110 were able to distinguish not only the sterile plants but also the cross-pollinated ones from the true hybrids of Gangyou 158,Ⅱ You 808, Wuyou 308 and Tianfengyou 316, and the results of purity identifi- cation using them were close that of field identification, in summary, several pairs of primers should be used for the purity identification of rice hybrids to distinguish all the off-type plants and thus improve the accuracy.展开更多
By inducing frequency, intensity and duration of lower temperature in the middle and last ten-day periods in August in the rice-growing areas of southern China, increasing temperature for safe seed production was defi...By inducing frequency, intensity and duration of lower temperature in the middle and last ten-day periods in August in the rice-growing areas of southern China, increasing temperature for safe seed production was defined as 2℃. During the sensitive period of fertility, characters of panicle height and canopy structure of TGMS rice, Pei＇ai64S, were measured. Results showed that temperature changes caused by irrigation in fields were below 40 cm of rice plant, and heating effect was significant at 20 cm when the temperature was increased by 3.1 ℃. For the present study, the following irrigation techniques were put forth： the water depth of 15-20 cm, current water used, irrigating after 17：00 and bailing at 10：00 in sunny or cloudy weather, irrigating on whole day, in shady or rainy weather, increasing inflows and outflows in large fields. In the present experiment, pollen fertility and self-fertilized seed setting rate accepted that the techniques were feasible and effective for against lower temperature and safeguarding seed production of two-line hybrid rice.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.31701390 and 31370349)Special Project on Performance Incentive Guidance of Chongqing Scientific Research Institution,China(Grant No.cstc2018jxjl80021)+1 种基金Chongqing Agriculture Development Fund(Grant No.NKY-2021AC003)Recruitment Announcement for High-level Talents of Yunnan University(Grant No.KL180018).
文摘In plants,a large number of anthocyanin biosynthetic genes encoding enzymes and regulatory genes encoding transcription factors are required for anthocyanin synthesis.Coleoptile purple lines are two purple lines on both sides of coleoptiles after seed germination.However,the molecular mechanism of coleoptile purple line is not clear in rice so far.In this study,two major dominant genes,coleoptile purple line 1(OsCPL1,also known as OsC1)and coleoptile purple line 2(OsCPL2),were isolated via map-based cloning,and both of them were required for anthocyanin biosynthesis of coleoptile purple line in rice.The knockout and complementation experiments confirmed that OsC1 was required for purple color in most organs,such as coleoptile line,sheath,auricle,stigma and apiculus,whereas OsCPL2 was just required for coleoptile purple line.OsC1 was predominantly expressed in coleoptiles,flag leaves,and green panicles,and highly expressed in young leaves,whereas OsCPL2 was predominantly expressed in coleoptiles,and extremely lowly expressed in the other tested organs.Loss-of-function of either OsC1 or OsCPL2 resulted in significant reduction of transcript levels of multiple anthocyanin biosynthesis genes in coleoptiles.Coleoptile purple line was further used as a marker trait in hybrid rice.Purity identification in hybrid rice seeds via coleoptile purple line just needed a little water,soil and a small plate and could be completed within 5 d.Molecular marker and field identification analyses indicated that coleoptile purple line was reliable for the hybrid seed purity identification.Our findings disclosed that coleoptile purple line in rice was regulated by two major dominant genes,OsC1 and OsCPL2,and can be used as a simple,rapid,accurate and economic marker trait for seed purity identification in hybrid rice.
文摘The seed samples of Yuetai A, a Honglian （HL） type cytoplasmic male sterile （CMS） line in hybrid rice were investigated to assess the seed purity and to analyze the cause of off-type plants by imitating the biological contaminant to Yuetai A in Nanjing, Jiangsu Province and Lingshui, Hainan Province during 2004-2006. The seed impurity of Yuetai A mainly resulted from the genetic drift of restoring fertility gene （Rt） after biological contamination but not from its sterility unstability. All of the ten maintainer lines, five restorer lines and three thermo-sensitive genic male sterile lines used in the study could pollinate Yuetai A and Yuetai B to produce F1 plants, directly or indirectly resulting in Rf-gene drifting into Yuetai A and generating ＇iso-cytoplasm restoring-generations＇. Furthermore, high outcrossing rate and similar heading date of Yuetai A with many varieties used in rice production might easily result in the biological contamination. After removing all plants with Rf-gene mixed in Yuetai A and preventing Rf-gene drifting into Yuetai A, the seed purity of Yuetai A and Yuetai B had been raised to 100%.
基金Supported by Special Fund for the Screening and Breeding of Low-Cd-accumulating Crop Varieties~~
文摘Different results of seed purity identification for Gangyou 158, Ⅱ You 808, Wuyou 308 and Tianfengyou 316 were obtained using different SSR primers in our early work. To find out the reasons, the four hybrid combinations were grown in field to identify their purity according to their phenotypic traits. Then, the results of field identification were compared with that of laboratory tests using different SSR primers. The comparison revealed that only sterile lines （female parent） were distin- guished from true hybrids using the primers RM208, RM264, RM242 and RM164 for the purity identification of Gangyou 158, II You 808, Wuyou 308 and Tianfengyou 316, so the results were higher than that of field identification. In contrast, the primers RM341, RM297, RM21 and RM110 were able to distinguish not only the sterile plants but also the cross-pollinated ones from the true hybrids of Gangyou 158,Ⅱ You 808, Wuyou 308 and Tianfengyou 316, and the results of purity identifi- cation using them were close that of field identification, in summary, several pairs of primers should be used for the purity identification of rice hybrids to distinguish all the off-type plants and thus improve the accuracy.
基金The research was supported by the National Natural Science Foundation of China （30370830）.
文摘By inducing frequency, intensity and duration of lower temperature in the middle and last ten-day periods in August in the rice-growing areas of southern China, increasing temperature for safe seed production was defined as 2℃. During the sensitive period of fertility, characters of panicle height and canopy structure of TGMS rice, Pei＇ai64S, were measured. Results showed that temperature changes caused by irrigation in fields were below 40 cm of rice plant, and heating effect was significant at 20 cm when the temperature was increased by 3.1 ℃. For the present study, the following irrigation techniques were put forth： the water depth of 15-20 cm, current water used, irrigating after 17：00 and bailing at 10：00 in sunny or cloudy weather, irrigating on whole day, in shady or rainy weather, increasing inflows and outflows in large fields. In the present experiment, pollen fertility and self-fertilized seed setting rate accepted that the techniques were feasible and effective for against lower temperature and safeguarding seed production of two-line hybrid rice.
