[Objective] This study aimed to establish a tissue culture technology for Leucophyta brownii ‘Canal Rocks Form’. [Method] Leucophyta brownii ‘Canal Rocks Form’ stems with axillary buds were selected as explants in...[Objective] This study aimed to establish a tissue culture technology for Leucophyta brownii ‘Canal Rocks Form’. [Method] Leucophyta brownii ‘Canal Rocks Form’ stems with axillary buds were selected as explants in vitro to investigate the effects of different concentrations of 6-BA and NAA on proliferation culture and the effects of IBA, NAA and subculture cycle on rooting culture. [Result] The results showed that Leucophyta brownii ‘Canal Rocks Form’ plantlets need low concentrations of phytohormones and the rooting culture was significantly affected by the subculture cycle; the optimal medium for proliferation culture was MS＋0.5 mg/L 6-BA＋0.05 mg/L NAA＋30 g/L sucrose＋5.5 g/L agar, with a proliferation coefficient of 4.25; the plantlets with a subculture cycle of 28 d were the most suitable for rooting culture, with a rooting rate of 95.9% in 1/2 MS＋0.1 mg/L IBA＋0.05 mg/L NAA＋20 g/L sucrose＋5.5 g/L agar, and the average number and length of roots were 4.69 and 1.68 cm, respectively. [Conclusion] This study laid the foundation for establishing sterile culture system of Leucophyta brownii ‘Canal Rocks Form’.展开更多
Anomozamites haifanggouensis (Kimura et al.) Zheng et Zhang comb. nov. is a characteristic Bennettitalean plant in Middle Jurassic flora. Only one specimen was collected from Haifanggou Formation (Middle Jurassic) in ...Anomozamites haifanggouensis (Kimura et al.) Zheng et Zhang comb. nov. is a characteristic Bennettitalean plant in Middle Jurassic flora. Only one specimen was collected from Haifanggou Formation (Middle Jurassic) in Daohugou village, Shantou town, Ningcheng County, Nei Mongol Autonomous Region, China. The stem of plant is slender and repeatedly branches as a dichasial system with a fertile shoot in the fork, forming equal and widely divergent branches, on the branches born with the fronds of Anomozamites type. Its reproductive organs consists of some microsporophylls and a few of the bracteoid small leaves (or receptacular leaves). Some scattered bracteoid leaves and microsporophylls were formerly considered by Pan as dicots. Since then, they were proposed to be a non-committal genus Pankuangia and described them as P. haifanggouensis by Kimura et al. In this study, we discover that these bracteoid small leaves and microsporophylls should be of Anomozamites. This discovery provides strong evidence for the 'Pankuangia' determination of the taxonomical position.展开更多
The reproductive biology of Schizopygopsis younghusbandi(Cyprinidae: Schizothoracinae) was studied by 719 individuals that collected from August 2008 to August 2009 in the middle reaches of Yarlung Tsangpo River, Chin...The reproductive biology of Schizopygopsis younghusbandi(Cyprinidae: Schizothoracinae) was studied by 719 individuals that collected from August 2008 to August 2009 in the middle reaches of Yarlung Tsangpo River, China. We coupled monthly variations of the gonadosomatic index(GSI), monthly proportions of the macroscopic maturity stages with size distribution of oocytes to evaluate spawning seasons. Taken as a set, these results indicated that S. younghusband i spawned from March to April with high degree of the spawning synchronicity. The standard lengths and the ages at 50% maturity for male were 222 mm and 4.4 year, and 308 mm and 7.0 year for female. In addition, the estimated mean fecundity and mean relative fecundity were 18682 and 57.8 eggs per g body weight. The fecundity of S. younghusbandi increased linearly with increasing of standard length and body weight. This study provides details about the S. younghusbandi reproduction suggesting that may be this species is vulnerable to exploitation in the middle reaches of Yarlung Tsangpo River.展开更多
The largest and most important family in Russian conifers is Pinaceae （27-29 species）. The most important problems in the field of systemitics concern some critical taxa. In the result of author＇s research, the new...The largest and most important family in Russian conifers is Pinaceae （27-29 species）. The most important problems in the field of systemitics concern some critical taxa. In the result of author＇s research, the new signs of vegetative and reproductive organs have been checked out and elaborated. It leads to the clarifying of new taxonomic status and geographical distribution of certain critical taxa. A set of species are threatened and need special measures which are included into the Red Data Book of Russian Federation. for their conservation. There are 13 species and one variety展开更多
基金Supported by Project of Development and Reform Commission of He'nan Province(2060403)~~
文摘[Objective] This study aimed to establish a tissue culture technology for Leucophyta brownii ‘Canal Rocks Form’. [Method] Leucophyta brownii ‘Canal Rocks Form’ stems with axillary buds were selected as explants in vitro to investigate the effects of different concentrations of 6-BA and NAA on proliferation culture and the effects of IBA, NAA and subculture cycle on rooting culture. [Result] The results showed that Leucophyta brownii ‘Canal Rocks Form’ plantlets need low concentrations of phytohormones and the rooting culture was significantly affected by the subculture cycle; the optimal medium for proliferation culture was MS＋0.5 mg/L 6-BA＋0.05 mg/L NAA＋30 g/L sucrose＋5.5 g/L agar, with a proliferation coefficient of 4.25; the plantlets with a subculture cycle of 28 d were the most suitable for rooting culture, with a rooting rate of 95.9% in 1/2 MS＋0.1 mg/L IBA＋0.05 mg/L NAA＋20 g/L sucrose＋5.5 g/L agar, and the average number and length of roots were 4.69 and 1.68 cm, respectively. [Conclusion] This study laid the foundation for establishing sterile culture system of Leucophyta brownii ‘Canal Rocks Form’.
文摘Anomozamites haifanggouensis (Kimura et al.) Zheng et Zhang comb. nov. is a characteristic Bennettitalean plant in Middle Jurassic flora. Only one specimen was collected from Haifanggou Formation (Middle Jurassic) in Daohugou village, Shantou town, Ningcheng County, Nei Mongol Autonomous Region, China. The stem of plant is slender and repeatedly branches as a dichasial system with a fertile shoot in the fork, forming equal and widely divergent branches, on the branches born with the fronds of Anomozamites type. Its reproductive organs consists of some microsporophylls and a few of the bracteoid small leaves (or receptacular leaves). Some scattered bracteoid leaves and microsporophylls were formerly considered by Pan as dicots. Since then, they were proposed to be a non-committal genus Pankuangia and described them as P. haifanggouensis by Kimura et al. In this study, we discover that these bracteoid small leaves and microsporophylls should be of Anomozamites. This discovery provides strong evidence for the 'Pankuangia' determination of the taxonomical position.
基金Supported by the Finance Special Fund of Chinese Ministry of Agriculture(Fisheries Resources and Environment Survey in the Key Water Areas of Tibet)
文摘The reproductive biology of Schizopygopsis younghusbandi(Cyprinidae: Schizothoracinae) was studied by 719 individuals that collected from August 2008 to August 2009 in the middle reaches of Yarlung Tsangpo River, China. We coupled monthly variations of the gonadosomatic index(GSI), monthly proportions of the macroscopic maturity stages with size distribution of oocytes to evaluate spawning seasons. Taken as a set, these results indicated that S. younghusband i spawned from March to April with high degree of the spawning synchronicity. The standard lengths and the ages at 50% maturity for male were 222 mm and 4.4 year, and 308 mm and 7.0 year for female. In addition, the estimated mean fecundity and mean relative fecundity were 18682 and 57.8 eggs per g body weight. The fecundity of S. younghusbandi increased linearly with increasing of standard length and body weight. This study provides details about the S. younghusbandi reproduction suggesting that may be this species is vulnerable to exploitation in the middle reaches of Yarlung Tsangpo River.
文摘The largest and most important family in Russian conifers is Pinaceae （27-29 species）. The most important problems in the field of systemitics concern some critical taxa. In the result of author＇s research, the new signs of vegetative and reproductive organs have been checked out and elaborated. It leads to the clarifying of new taxonomic status and geographical distribution of certain critical taxa. A set of species are threatened and need special measures which are included into the Red Data Book of Russian Federation. for their conservation. There are 13 species and one variety
