The Analysis Of Cytogenetic And The Leaf Epidermal Microfeatures Of Scutellaria Linn. In Junyun Mountain

Scutellaria Linn. is one genus below the Labiatae.In China there is about 100 species,which widely distributed in all the south and north..Four species in Chongqing Jinyun mountain,they are:Scutellaria tsinyunensis C. Y. Wu et S. Chow、S. yunnanensis Levl.、S. franchetiana Levl.、 S.indica Linn.。 And the S. tsinyunensis C. Y. Wu et S. Chow belong to the grade one of protected plants in Chongqing,is one kind of endangered plant species in Chongqing area, especially require various kind of scientific research recently.The chromosome karyotype and leaf epidermal micromorphology of the four speices in Jinyun mountain were established in this study, The analysis of karyotype formula and karyotype type were compared in this study.Use Photoshop 6.0 to measure the length of the chromosome、epidermic cell and proportion of each part of the leaf epidermal,and draw the idiogram by Excel and Drawing Tool,making a preliminary comparison of the karyotype sturcture, genetic relationship and evolutionary relationships of the four species. Typical results are shown below:Basing on the primary plant chromosome karyotype analysis method,we have improved the technique of karyotype analysis and found a karyotype analysis method for Scutellaria. Because of the low ratio of seed germination and strongly dependence on season,we used the hydroponic cuttage method to obtain the roots. Cut off root tip till root length to 0.5-1 cm;Tender tissues were pretreated with 0.002mol/L 8-hydroxylquinoline for 6-8h;Use Carnoy’s I fixation fluid(acetic: alcohol=1:3 freshly prepared)to soaked the root for 12-24h;Disintegrated the root in the improved dissociation solution(HCl:C2H6O=1:1) for 10-20 min in room temperature; Stained with Carbol fuchsin overnight, tabletting, microscopic examination. The arrangements of chromosomes and pairing were made using of Photoshop6.0,drawing the idiogram by Excel.The chromosome number of The four species of Scutellaria in Junyun mountain are all 26,except the S. Franchetiana Levl.(24);they are all diploid.The four species were mainly consisted of metacentric chromosome and submetacentric chromosome, their karyotypes were symmetrical and seemed to be primitive types. Its karyotype formula was:2n=2x=26=24m+2sm,The karyotype classification of S. tsinyunensis C. Y. Wu et S. Chow was:"1B";Its karyotype formula was: 2n=2x=26=26m,The karyotype classification of S. yunnanensis Levl. was:"1B";The karyotype formula of S. franchetiana Levl.was:2n=2x=24=20m+4sm,Its karyotype classification was:"2B";The karyotype formula of S.indica Linn.was:2n=2x=26=20m+6sm(1SAT),Its karyotype classification was:"2B".Compare the karyotype of the four species of Scutellaria Linn., we can know that the karyotype of S. tsinyunensis C. Y. Wu et S. Chow and S. yunnanensis Levl. are "1B", the karyotype of S. franchetiana Levl.and S.indica Linn, are "2B";it proved that the S. franchetiana Levl. and S.indica Linn, had a closer genetic relationship and a higher evolutionary status;S. tsinyunensis C. Y. Wu et S. Chow and S. yunnanensis Levl. had similar origin status,they are closer species and share a lower evolutionary status.We using three methods (immediate tearing、picking after boliing、enamel printing) to get the upper and lower leaf epidermis of the four species.Making microscopic examination to analysis each part of the leaf epidermal,keeping a record of their length、quantity and density;the result showed that:these four species had a common character in leaf epidermal type,there is no stoma in upper epidemis and no significant differences between their epidermal cells,the S.indica shows a little evolutionary of four;analysis the lower epidemis,we found that the stoma of S. yunnanensis Levl. shows more acclimatization,no significant differences in other species.They all have the epidermal hair except S. yunnanensis Levl. According the morphological characteristics and the density of the epidermal hair,S.indica Linn. has a denser epidermal hair,we infer that it must be one of the character to adapt the environment to keep its vital force and fecundity. And the research of the leaf epidermal micromorphology proved S.indica Linn. to be the most evolutional sepcies of the four spieces,this result would be substantiated by the consequence of the chromosome karyotype,and S. yunnanensis Levl. seemd to be the primitive species.According to these conclusions.based on the level of karyotypic symmetry and the analysis of tissues in the leaf epidermal of the Scutellaria. S.indica Linn. is evolutionaryS. franchetiana Levl. and S. tsinyunensis C. Y. Wu et S. Chow seemed to be more primitive,S. yunnanensis Levl. is the most primitive speices.The evolutional trend of the four species is:S.indica Linn.>S. franchetiana Levl.>S. Tsinyunensis C. Y. Wu et S. Chow>S. yunnanensis Levl.We make a fundamental research of the four species of Scutellaria by karyotype and leaf epidermal micromorphology analysis to support the follow-up study,especially for protection and breed of the endangered plant species in area --- S. tsinyunensis C. Y. Wu et S. Chow.