In order to study vegetation evolution and environmental changes around 2.5 Ma B.P., a total of 146 pollen samples with an average time resolution of 7 000 years were analyzed in the deep-sea record at the depth of 13...In order to study vegetation evolution and environmental changes around 2.5 Ma B.P., a total of 146 pollen samples with an average time resolution of 7 000 years were analyzed in the deep-sea record at the depth of 135 - 95 m （in composition depth） from ODP Site 1143 （9° 22＇ N, 113° 17＇ E） in the southern South China Sea. The results show that the pollen influx has a distinct change. During 2.6 - 2.0 Ma B.P., the average value of pollen influx increased evidently compared with that of 3.0 - 2.6 Ma B.P. It shows that the sea level of SCS dropped dramatically around 2.6 Ma B.P., corresponding to the formation of the Northern Hemisphere ice-sheets and the enhancement of the East Asian Monsoon. The pollen influx variations reflect the glacial-interglacial cycles corresponding with the deep-sea oxygen isotope curve and indicate that the sea level of SCS rose and dropped many times after 2.6 Ma B.P. The spectrum analysis results of pollen influx show that there are cycles at 0.1Ma （eccentricity） and 46.9 ka （obliquity） during 3.0 - 2.0 Ma B.P.展开更多
Pollen viability study on Piper colubrinum Link. carried out to develop interspecific hybridization between P. nigrum L. and P. colubrinum Link.. This plant has good potential as a donor plant in breeding programme fo...Pollen viability study on Piper colubrinum Link. carried out to develop interspecific hybridization between P. nigrum L. and P. colubrinum Link.. This plant has good potential as a donor plant in breeding programme for Phytophthora to foot rot resistance in the cultivated species, P. nigrum. This project was carried out to reveal the optimum time to collect pollen of P. colubrinum for artificial pollination. Through this study, anther dehiscence was proved occurred around 9 am. Based on the result obtained from study on the time of anther dehiscence, the pollen was classified into five stages for testing on the viability, i.e., stage 1, before anther dehiscence, i.e., around 7 am （pollen obtained by crushing on the anther）; stage 2： immediately after anther dehiscence, i.e., around 9 am; stage 3： two hours after anther dehiscence, i.e., around 11 am; stage 4： four hours after anther dehiscence, i.e., around 1 pm; and stage 5： six hours after anther dehiscence, i.e., around 3 pm. Data obtained from pollen germination and pollen tube growth study showed that pollen of P. colubrinum was the most viable at two hours after anther dehiscence and onward. It was also proved that the viability can be maintained up to at least eight hours. Pollen obtained before anther dehiscence by crushing on the anther was found less viable with lower percentage of pollen germination and retarded pollen tube growth. In other words, the experiment enlightened that artificial pollination between P. nigrum L. and P. colubrinum Link was ideally to be carded out approximately starting from 11 am until 5 pm, considering the viability of pollen ofP. colubrinum.展开更多
In this article, the functions of D-myo-inositol-1,4,5-trisphosphate (Ins [1,4,5] P3) in regulating pollen tube polar growth were investigated by application of caged version of the phosphoinositides. To increase the ...In this article, the functions of D-myo-inositol-1,4,5-trisphosphate (Ins [1,4,5] P3) in regulating pollen tube polar growth were investigated by application of caged version of the phosphoinositides. To increase the intracellular Ins（1,4,5）P3 concentration at the apical region of pollen tube, the caged Ins（1,4,5）P3 loaded by osmotic shock was activated by 10 s 360 nm UV flash at this domain （10 μm from the tip）. More than 70% pollen tubes were induced swelling at apex and/or growth axis reorientation, accompanying temporarily growth arrest, by localized increase of Ins（1,4,5）P3 concentration （n=21）. While, pollen tubes without being loaded with caged Ins（1,4,5）P3 had not response to the same dosage UV flash. With FM 1-43 fluorescent staining, it was found that growth perturbation by UV activated caged Ins（1,4,5）P3 had tight link with membrane trafficking at the apical zone of pollen tubes. Upon UV pulse, the apical V-shaped bright area where was full of secretory vesicles spread to a much broader region, which implied that actin filaments at the apical region were remodeled. It was also observed that the FM 1-43 fluorescence intensity at tip remarkably increased than that before UV flash, which demonstrated that more secretory vesicles were accumulated at this region. To estimate the role of Ins（1,4,5）P3 in modulating intracellular calcium concentration and distribution, dextran conjugated fluorescent dye Calcium Green-1 and Rhodamine B were microinjected into pollen tubes together with caged Ins（1,4,5）P3. The results showed that calcium concentration at the subapical region increased upon UV released Ins（1,4,5）P3. Consequently, the tip-focused calcium gradient under the apical dome of pollen tube was disturbed. Simultaneously, the pollen tube bulged at the apical region and its growth rate decreased. As the tip-focused calcium gradient was reestablished, the pollen tube morphology and growth recovered to the normal level. Therefore, Ins（1,4,5）P3 can modulate pollen tube growth rate and direction through mobilizing intracellular calcium and regulating vesicle trafficking during pollen tube finding its way to the ovary.展开更多
对紫斑牡丹花粉的化学成分进行研究,综合运用硅胶、聚酰胺、Sephadex LH-20凝胶柱色谱及制备型高效液相等色谱技术,从该花粉70%乙醇提取物的乙酸乙酯萃取部位分离得到18个化合物,其结构由HR-ESI-MS、1H和13 C NMR等波谱学方法鉴定为腺苷...对紫斑牡丹花粉的化学成分进行研究,综合运用硅胶、聚酰胺、Sephadex LH-20凝胶柱色谱及制备型高效液相等色谱技术,从该花粉70%乙醇提取物的乙酸乙酯萃取部位分离得到18个化合物,其结构由HR-ESI-MS、1H和13 C NMR等波谱学方法鉴定为腺苷(1)、芹菜素(2)、柠檬黄素(3)、8-甲氧基山萘酚(4)、槲皮素(5)、柠檬素-3-β-D-葡萄糖苷(6)、sexangularetin-3-O-y1-β-D-sophoroside(7)、limocitrin-3-O-y1-β-D-sophoroside(8)、芍药苷(9)、芍药内酯苷(10)、氧化芍药苷(11)、β-谷甾醇(12)、没食子酸(13)、肉豆蔻酸(14)、亚油酸(15)、对羟基苯甲醛(16)、邻苯二甲酸二戊酯(17)和蔗糖(18),以上化合物均为首次从紫斑牡丹花粉中分离得到,其中化合物3、4、6为首次从该属植物中分离得到。展开更多
研究甘蔗属与滇蔗茅属间远缘杂交F1染色体遗传行为具有重要科学意义,可为发掘利用滇蔗茅野生优异基因资源提供细胞学依据。本研究采用常规压片技术对可育父本及不育杂交F1花粉母细胞减数分裂过程进行比较观察,结果显示可育父本云南95-1...研究甘蔗属与滇蔗茅属间远缘杂交F1染色体遗传行为具有重要科学意义,可为发掘利用滇蔗茅野生优异基因资源提供细胞学依据。本研究采用常规压片技术对可育父本及不育杂交F1花粉母细胞减数分裂过程进行比较观察,结果显示可育父本云南95-19减数分裂正常,而不育杂交F1分裂异常;进一步对F1花粉母细胞减数分裂过程进行基因组荧光原位杂交(GISH,genome in situ hybridization)分析,结果表明:滇蔗茅与甘蔗属热带种的亲缘关系较远,双亲染色体在F1细胞中不能进行同源配对,终变期,15条滇蔗茅染色体以单价体形式存在,花粉母细胞减数分裂细胞中存在滞后染色体、染色体丢失和不均衡分离现象。甘蔗-滇蔗茅属间远缘杂交F1花粉母细胞减数分裂异常因而杂交F1花粉完全败育。展开更多
基金the National Natural Science Foundation of China projects （40371116） the National Major Basic Research Program of China （G200078502）.
文摘In order to study vegetation evolution and environmental changes around 2.5 Ma B.P., a total of 146 pollen samples with an average time resolution of 7 000 years were analyzed in the deep-sea record at the depth of 135 - 95 m （in composition depth） from ODP Site 1143 （9° 22＇ N, 113° 17＇ E） in the southern South China Sea. The results show that the pollen influx has a distinct change. During 2.6 - 2.0 Ma B.P., the average value of pollen influx increased evidently compared with that of 3.0 - 2.6 Ma B.P. It shows that the sea level of SCS dropped dramatically around 2.6 Ma B.P., corresponding to the formation of the Northern Hemisphere ice-sheets and the enhancement of the East Asian Monsoon. The pollen influx variations reflect the glacial-interglacial cycles corresponding with the deep-sea oxygen isotope curve and indicate that the sea level of SCS rose and dropped many times after 2.6 Ma B.P. The spectrum analysis results of pollen influx show that there are cycles at 0.1Ma （eccentricity） and 46.9 ka （obliquity） during 3.0 - 2.0 Ma B.P.
文摘Pollen viability study on Piper colubrinum Link. carried out to develop interspecific hybridization between P. nigrum L. and P. colubrinum Link.. This plant has good potential as a donor plant in breeding programme for Phytophthora to foot rot resistance in the cultivated species, P. nigrum. This project was carried out to reveal the optimum time to collect pollen of P. colubrinum for artificial pollination. Through this study, anther dehiscence was proved occurred around 9 am. Based on the result obtained from study on the time of anther dehiscence, the pollen was classified into five stages for testing on the viability, i.e., stage 1, before anther dehiscence, i.e., around 7 am （pollen obtained by crushing on the anther）; stage 2： immediately after anther dehiscence, i.e., around 9 am; stage 3： two hours after anther dehiscence, i.e., around 11 am; stage 4： four hours after anther dehiscence, i.e., around 1 pm; and stage 5： six hours after anther dehiscence, i.e., around 3 pm. Data obtained from pollen germination and pollen tube growth study showed that pollen of P. colubrinum was the most viable at two hours after anther dehiscence and onward. It was also proved that the viability can be maintained up to at least eight hours. Pollen obtained before anther dehiscence by crushing on the anther was found less viable with lower percentage of pollen germination and retarded pollen tube growth. In other words, the experiment enlightened that artificial pollination between P. nigrum L. and P. colubrinum Link was ideally to be carded out approximately starting from 11 am until 5 pm, considering the viability of pollen ofP. colubrinum.
文摘In this article, the functions of D-myo-inositol-1,4,5-trisphosphate (Ins [1,4,5] P3) in regulating pollen tube polar growth were investigated by application of caged version of the phosphoinositides. To increase the intracellular Ins（1,4,5）P3 concentration at the apical region of pollen tube, the caged Ins（1,4,5）P3 loaded by osmotic shock was activated by 10 s 360 nm UV flash at this domain （10 μm from the tip）. More than 70% pollen tubes were induced swelling at apex and/or growth axis reorientation, accompanying temporarily growth arrest, by localized increase of Ins（1,4,5）P3 concentration （n=21）. While, pollen tubes without being loaded with caged Ins（1,4,5）P3 had not response to the same dosage UV flash. With FM 1-43 fluorescent staining, it was found that growth perturbation by UV activated caged Ins（1,4,5）P3 had tight link with membrane trafficking at the apical zone of pollen tubes. Upon UV pulse, the apical V-shaped bright area where was full of secretory vesicles spread to a much broader region, which implied that actin filaments at the apical region were remodeled. It was also observed that the FM 1-43 fluorescence intensity at tip remarkably increased than that before UV flash, which demonstrated that more secretory vesicles were accumulated at this region. To estimate the role of Ins（1,4,5）P3 in modulating intracellular calcium concentration and distribution, dextran conjugated fluorescent dye Calcium Green-1 and Rhodamine B were microinjected into pollen tubes together with caged Ins（1,4,5）P3. The results showed that calcium concentration at the subapical region increased upon UV released Ins（1,4,5）P3. Consequently, the tip-focused calcium gradient under the apical dome of pollen tube was disturbed. Simultaneously, the pollen tube bulged at the apical region and its growth rate decreased. As the tip-focused calcium gradient was reestablished, the pollen tube morphology and growth recovered to the normal level. Therefore, Ins（1,4,5）P3 can modulate pollen tube growth rate and direction through mobilizing intracellular calcium and regulating vesicle trafficking during pollen tube finding its way to the ovary.
文摘对紫斑牡丹花粉的化学成分进行研究,综合运用硅胶、聚酰胺、Sephadex LH-20凝胶柱色谱及制备型高效液相等色谱技术,从该花粉70%乙醇提取物的乙酸乙酯萃取部位分离得到18个化合物,其结构由HR-ESI-MS、1H和13 C NMR等波谱学方法鉴定为腺苷(1)、芹菜素(2)、柠檬黄素(3)、8-甲氧基山萘酚(4)、槲皮素(5)、柠檬素-3-β-D-葡萄糖苷(6)、sexangularetin-3-O-y1-β-D-sophoroside(7)、limocitrin-3-O-y1-β-D-sophoroside(8)、芍药苷(9)、芍药内酯苷(10)、氧化芍药苷(11)、β-谷甾醇(12)、没食子酸(13)、肉豆蔻酸(14)、亚油酸(15)、对羟基苯甲醛(16)、邻苯二甲酸二戊酯(17)和蔗糖(18),以上化合物均为首次从紫斑牡丹花粉中分离得到,其中化合物3、4、6为首次从该属植物中分离得到。
文摘研究甘蔗属与滇蔗茅属间远缘杂交F1染色体遗传行为具有重要科学意义,可为发掘利用滇蔗茅野生优异基因资源提供细胞学依据。本研究采用常规压片技术对可育父本及不育杂交F1花粉母细胞减数分裂过程进行比较观察,结果显示可育父本云南95-19减数分裂正常,而不育杂交F1分裂异常;进一步对F1花粉母细胞减数分裂过程进行基因组荧光原位杂交(GISH,genome in situ hybridization)分析,结果表明:滇蔗茅与甘蔗属热带种的亲缘关系较远,双亲染色体在F1细胞中不能进行同源配对,终变期,15条滇蔗茅染色体以单价体形式存在,花粉母细胞减数分裂细胞中存在滞后染色体、染色体丢失和不均衡分离现象。甘蔗-滇蔗茅属间远缘杂交F1花粉母细胞减数分裂异常因而杂交F1花粉完全败育。
