ABSTRACT
Objective To observe the effect of fructose(Fru),glucose (Glc)and exogenous nitric oxide donor sodium nitroprusside(SNP)on the germination of Psychotria rubra(Lour.)Poir. seeds under drought stress,and to explore the optimal concentration for clearing the drought stress. Methods We established the drought stress model of Psychotria rubra(Lour.)Poir. seeds with 15％(volume fraction)PEG6000 and 0.4 mol/L D-mannitol, measured the germination rate and germination index of Psychotria rubra (Lour.)Poir. seeds under drought stress combined treatment with different concentrations of Fru (0,300,500 μmol/L),Glc (0,300,500 μmol/L) and SNP(0 , 100 , 200 μmol/L). Results The germination process of Psychotria rubra(Lour .) Poir . seeds was significantly suppressed by drought stress. Fru,Glc and SNP could significantly promote the germination of Psychotria rubra (Lour.) Poir. seeds under drought stress. The optimal condition for clearing drought stress induced by 15％ PEG6000 was Fru 300 μmol/L, Glc 500 μmol/Land SNP 200 μmol/L, and the germination rate was 95％ under the optimal condition . The optimal condition for clearing drought stress induced by D-Mannitol was Fru 500 μmol/L, Glc 500 μmol/L and SNP 100 μmol/L, and the germination rate arrived to100％. Conclusion Fru,Glc and SNP can significantly alleviate the negative impact induced by drought stress for the Psychotria rubra(Lour.)Poir. seed germination,improve the drought-resistant ability of the seeds.
ABSTRACT
Objective To compare the pharmacognosy characteristics of aerial roots of Ficus microcarpa Linn.f. and Ficus elastica Roxb. ex Hornem.. Methods Fresh aerial roots were harvested and were used as the experimental samples. Stereoscopy was used for the observation of macroscopic appearance of Ficus microcarpa Linn.f. and Ficus elastica Roxb. ex Hornem.,and the microscope was used for the examination of their microscopic features of the velamen surface, cross section of root tip, cross section and longitudinal section of the posterior root, and powder. Results The appearance characteristics of the two species were as follows:the number of aerial roots of Ficus microcarpa Linn. f. was more,and the diameter was smaller than that of Ficus elastica Roxb. ex Hornem. The root tips of Ficus microcarpa Linn. f. aerial roots were light yellow turning to yellow-white, covered with gray or yellowish-white lenticels;the root tips of Ficus elastica Roxb. ex Hornem. aerial roots were light yellow or yellow, covered with gray lenticels. Microscopic identification results of the two plants were as follows:the primary xylems of transverse section of root tips and posterior roots of Ficus microcarpa Linn.f. and Ficus elastica Roxb. ex Hornem. were different,the former being five to seven heptarch,and the latter being six to eleven heptarch. Both of the two species had non-articulated unbranched laticifers in their longitudinal section of posterior root, and the diameter of Ficus. elastica Roxb. ex Hornem. was slightly larger than that of Ficus microcarpa Linn. f.. The powder of Ficus microcarpa Linn. f. was red brown,with spiral and pitted vessels;Ficus elastica Roxb. ex Hornem. was yellow brown,with single small and large pitted vessels,and the color of its fiber was shallow or nearly colorless or even transparent, with lines of cluster crystal. Conclusion The results will provide evidence for the identification , exploitation and utilization of Ficus microcarpa Linn . f . and Ficus elastica Roxb. ex Hornem.
ABSTRACT
Objective To identify the pharmacognosy features of Dichrocephala auriculata(Thunb.)Druce,and to summarize its identification characteristics,so as to lay a foundation for further study and development of the drug. Methods By original plant identification and microscopic identification methods,we observed the features of the whole plant of Dichrocephala auriculata(Thunb.)Druce. Results The morphological characteristics of the original plant showed as follows:the whole aerial part was covered with tomentum;roots belonged to taproot root system;the alternate leaves were long oval-shaped, pinnatipartite, or divided;flowers were small, presented as capitulum, arranging in umbrella-shape, with several outer layers of white flowers and several inner layers of yellow green flowers. Microstructure characteristics showed as follows:root vascular bundle was broad,and pericycle fiber bundles were found outside;stem vascular bundle had 8-25 cyclocytics,pericycle fibers were found outside, and the medulla was broad with myelinated fibers around;the upper and below epidermis of leaves had stomata and non-tentacle, and the main vein vascular of the leaf was collateral with vascula bundles upside and downside;the nonglandular hairs,starch grains,fibers,pollen grains,and tubes were shown in the powder of whole plant. Conclusion The above results are stable and reliable, and can be applied for pharmacognosy identification of Dichrocephala auriculata(Thunb.)Druce.