Observation of Multiple Broadband Alfvénic Chirping Modes in HL-2A NBI Plasmas

Multiple broadband Alfvenic chirping modes(CMs),with frequencies in the wide range of f-35-150 kHz and chirping down rapidly,are found in HL-2A neutral beam injection plasmas,and the CMs can even coexist.The frequency chirping down process can be completed within-1 ms,and the frequency shift can reach 30-50 kHz.The CMs propagate in ion diamagnetic drift directions poloidally.The toroidal mode number is confirmed to be n=1,2,3 and 4 for the f-35-65,55-90,70-120 and 100-150 kHz CMs,respectively.The CMs are more like to be energetic-particle continuum modes(EPMs),since the modes almost locate on the Alfven continuum.

MALE STERILITY 3 encodes a plant homeodomain-finger protein for male fertility in soybean

Male-sterile plants are used in hybrid breeding to improve yield in soybean(Glycine max(L.)Merr.).Developing the capability to alter fertility under different environmental conditions could broaden germplasm resources and simplify hybrid production.However,molecular mechanisms potentially underlying such a system in soybean were unclear.Here,using positional cloning,we identified a gene,MALE STERILITY 3(MS3),which encodes a nuclear-localized protein containing a plant homeodomain(PHD)-finger domain.A spontaneous mutation in ms3 causing premature termination of MS3 translation and partial loss of the PHD-finger.Transgenetic analysis indicated that MS3 knockout resulted in nonfunctional pollen and no selfpollinated pods,and RNA-seq analysis revealed that MS3 affects the expression of genes associated with carbohydrate metabolism.Strikingly,the fertility of mutant ms3 can restore under longd conditions.The mutant could thus be used to create a new,more stable photoperiod-sensitive genic male sterility line for two-line hybrid seed production,with significant impact on hybrid breeding and production.

A reference-grade genome assembly for Astragalus mongholicus and insights into the biosynthesis and high accumulation of triterpenoids and flavonoids in its roots

Astragalus membranaceus var.mongholicus(AMM),a member of the Leguminosae,is one of the most important medicinal plants worldwide.The dried roots of AMM have a wide range of pharmacological effects and are a traditional Chinese medicine.Here,we report the first chromosome-level reference genome of AMM,comprising nine pseudochromosomes with a total size of 1.47 Gb and 27868 protein-encoding genes.Comparative genomic analysis reveals that AMM has not experienced an independent wholegenome duplication(WGD)event after the WGD event shared by the Papilionoideae species.Analysis of long terminal repeat retrotransposons suggests a recent burst of these elements at approximately 0.13 million years ago,which may explain the large size of the AMM genome.Multiple gene families involved in the biosynthesis of triterpenoids and flavonoids were expanded,and our data indicate that tandemduplication has been the main driver for expansion of these families.Among the expanded families,the phenylalanine ammonia-lyase gene family was primarily expressed in the roots of AMM,suggesting their roles in the biosynthesis of phenylpropanoid compounds.The functional versatility of 2,3-oxidosqualene cyclase genes in cluster Ⅲ may play a critical role in the diversification of triterpenoids in AMM.Our findings provide novel insights into triterpenoid and flavonoid biosynthesis and can facilitate future research on the genetics and medical applications of AMM.

Import of Rift Valley fever to China:a potential new threat?

Several recent studies in Virologica Sinica and other journals have highlighted the enormous international challenge of emerging arboviral diseases,such as Zika virus disease,dengue,and chikungunya(Islam et al.,2015;Maurice et al.,2015;Dai et al.,2016;Deng et al.,2016;Song et al.,2016;Wang et al.,2016;Xu et al.,2016;Zhang et al.,2016;Zhou