Determination of Total Flavonoids Contents in Leaves and Branches of 33 Mulberry Germplasm Resources in Yunnan Sericultural Area

In this study,the contents of total flavonoids in leaves and branches of 33 mulberry germplasm resources from 6 mulberry species,namely Morus multicaulis Perr.,Morus alba Linn.,Morus atropurpurea Roxb.,Morus australis Poir, Morus laevigata Wall.,Morus wittiorum Hand-Mazz,in sericultural areas of Yunnan Province were determined by Al(NO 3)3-NaNO 2 colorimetry to screen breeding materials of mulberry varieties suitable for development of medicinal and food products. The results indicated that the contents of total flavonoids in leaves of 33 mulberry germplasm resources displayed normal distribution as a whole. Mass ratio of total flavonoids in mulberry leaves of 93. 94% test samples was distributed from 10. 00 to 35. 00 mg/ g,that of 96. 97% test samples was distributed from 2. 00 to 15. 00 mg/ g. In most mulberry germplasm resources,the contents of total flavonoids in branches were lower than those in leaves. There was significant difference in total flavonoids contents from leaves and branches between various mulberry germplasm resources(P0. 05),while there was no significant difference between the 6 mulberry species and between local varieties and artificial bred varieties(P0. 05). Leaves of Cangxisang from M. alba Linn. had the highest levels of total flavonoids, with mass ratio as high as 35. 27 mg/ g. Meanwhile,the mass ratio of total flavonoids in branches of Puer 8 from M. wittiorum Hand-Mazz had the highest level of total flavonoids,with mass ratio as high as 19. 49 mg/ g. These two local varieties could be used as breeding materials for new mulberry varieties cultivation for development of medicinal and food products.