Anther Culture And Biological Characteristics Study On Regenerated Plants Of Dendrocalamus Latiflorus

We developed an efficient system to regenerate Dendrocalamus latiflorus(tropical giant bamboo)using in vivo anther to generate calli in M8 medium supplemented with plant growth regulators at optimal concentrations.To identify the optimal growing conditions for callus induction and shoot differentiation,experiments were carried out using an orthogonal design.Regeneration plants were initiated from bamboo anthers,and chromosome number and nuclear DNA content were detected by chromosome analysis and flow cytometry.Comparision of the biological characteristics,growth vigor,anatomical structure and physiological indexes were made between the seedlings and anther regeneration plants of Dendrocalamus latiflorus.The conclusions are as the followings1.The highest callus induction rate(5.08 ± 0.606 %)was obtained in M8 medium supplemented with 1 mg/L NAA,0.3 mg/L 6-BA,15 mg/L PAA,7.5 mg/L STS,500 mg/L CH,100 mg/L proline,100 mg/L glutamine,5.4% maltose,and 0.8% agar.2.Optimal conditions for shoot differentiation(28.3 ± 4.29%)and subsequent shoot growth were also obtained in M8 medium supplemented with 1 mg/L KT,3 mg/L 6-BA,0.2mg/L NAA and 15 mg/L PAA,7.5 mg/L STS,500 mg/L CH,100 mg/L proline,100 mg/L glutamine,5.4% maltose,and 0.8% agar.3.Among the 100 regeneration plantlets,1 was haploid,3 were double haploid and the chromosome number of the other regeneration plants were twice that of the parents.4.Among the anther regeneration plants and seedlings,there was some correlation between chromosome dosage and chlorophyll content.5.Comparison of the seedlings and anther regeneration plants on leaves anatomical structure indicated that the stomatal size,the spindle cells' size and the leaves' thickness were frequently associated with increasing in ploidy level of the tested plantlets;however,there was no correlation between lower epidermis' thickness and chromosome dosage.6.The double hexaploid plantlets showed higher indexes on photosynthesis and transpiration rate than the hexaploid ones as examined by Li-6400 Photosynthesis System.Based on the above investigation,it could be conclude that there was some correlation between biological characteristics and chromosome dosage.And in fact seedlings' height,stem diameter,leaf length and leaf width are significantly higher than that of anther regeneration plants,but on the aspect of the number of shoots,stomatal size,chlorophyll content and fluorescence parameters,photosynthesis and transpiration,anther regeneration plants(12x)are significantly higher than that of hexaploid.Our study provides an innovative method for bamboo plant regeneration and a useful method for genetic improvement.