The chromosome-scale genome assembly, annotation and evolution of Rhododendron henanense subsp. lingbaoense.

Rhododendron henanense subsp. lingbaoense (hereafter referred to as R. henanense) is an endemic species naturally distributed in the Henan province, China, with high horticultural, ornamental and medicinal value. Herein, we report a de novo genome assembly for R. henanense using a combination of PacBio long read and Illumina short read sequencing technologies. In total, we assembled 634.07 Mb with a contig N50 of 2.5 Mb, representing ~96.93% of the estimated genome size. By applying Hi-C data, 13 pseudochromosomes of R. henanense genome were assembled, covering ~98.21% of the genome assembly. The genome was composed of ~65.76% repetitive sequences and 31,098 protein-coding genes, 88.77% of which could be functionally annotated. Rhododendron henanense displayed a high level of synteny with other Rhododendron species from the Hymenanthes subgenus. Our data also suggests that R. henanense genes related to stress responses have undergone expansion, which may underly the unique abiotic and biotic stress resistance of the species. This alpine Rhododendron chromosome-scale genome assembly provides fundamental molecular resources for germplasm conservation, breeding efforts, evolutionary studies, and elucidating the unique biological characteristics of R. henanense.

[Determination of 9 isoflavonoids in Puerariae Lobatae Radix with quantitative analysis of multi-components by single marker].

A method for determination of 9 isoflavones in Puerariae Lobatae Radix was established and the accuracy and feasibility of the method were verified. The relative correction factors of eight isoflavonoids,3'-hydroxy puerarin,puerarinapioside,3'-methoxy puerarin,puerarin 6″-O-xyloside,daidzin,genistin,formononetin and daidzein were determined by HPLC method with puerarin as the internal standard. The contents of 9 isoflavonoids in 11 batches of samples were determined by external standard method and QAMS.The accuracy and feasibility of the methods were evaluated by comparison of the quantitative results between external standard method and QAMS. The reproducibility of the relative correction factors was good under different experimental conditions,and there was no significant difference between the external standard method of the 9 compounds and the content of QAMS method. The results showed that using puerarin as an internal standard to simultaneously determine the 8 isoflavonoids mentioned above is accurate and feasible. Thus,it can be used as quality control of Puerariae Lobatae Radix.