Screening of the Indoor Plants for Removing Formaldehyde

[ Objective] The research aimed to screen out the best ornamental houseplants to remove formaldehyde from indoor air through deposition velocity and to explore the pathways of plants for formaldehyde removal. [ Method] Fifty-three indoor ornamental plant species were experimen- ted in series of sealed chambers （volumes of O. 096 m^3 ） by formaldehyde fumigation with the internal concentration of （1 ± 0. 1 ） mg/L in this study. The removal efficiency of formaldehyde was assessed by the uptake fluxes and the deposition velocity of formaldehyde. [ Result] Six species of indoor plants （ Hedera helix, Ficus elastica Roxb. ex Hornem, Nephrolepis exaltata cv. Bostoniensis, Begonia evansiana, Mentha canadensis L. and Adiantum capillus-veneris Linn. ） with high formaldehyde removal efficiency were firstly screened out. Significance analysis of the deposition velocity by Statistical Program for Social Sciences （SPSS） presented that tested plants belonging to the same genera or family had similar ability to remove formaldehyde pollution. The diurnal variations of deposition velocity for the six plants were then tested further. The results showed that four of them, including Ficus elastica Roxb. ex Hornem, Nephrolepis exaltata cv. Bostoniensis, Mentha canadensis L. and Adiantum capi//us-veneris Linn. re- moved formaldehyde mainly by leaves surface adsorption, while Begonia evansiana and Hedera helix by stomatal uptake, f Conclusion Begonia evansiana and Hedera helixare the most efficient indoor plants among the 53 species studied for phytoremediation of the air formaldehyde pollution.

OsNAC120 balances plant growth and drought tolerance by integrating GA and ABA signaling in rice

The crosstalk between gibberellin(GA)and abscisic acid(ABA)signaling is crucial for balancing plant growth and adaption to environmental stress.Nevertheless,the molecular mechanism of their mutual antagonism still remains to be fully claried.In this study,we found that knockout of the rice NAC(NAM,ATAF1/2,CUC2)tran-scription factor gene OsNAC120 inhibits plant growth but enhances drought tolerance,whereas OsNAC120 overexpression produces the opposite results.Exogenous GA can rescue the semi-dwarf phenotype of osnac120 mutants,and further study showed that OsNAC120 promotes GA biosynthesis by transcriptionally activating the GA biosynthetic genes OsGA20ox1 and OsGA20ox3.The DELLA protein SLENDER RICE1(SLR1)interacts with OsNAC120 and impedes its transactivation ability,and GA treatment can remove the inhi-bition of transactivation activity caused by SLR1.On the other hand,OsNAC120 negatively regulates rice drought tolerance by repressing ABA-induced stomatal closure.Mechanistic investigation revealed that OsNAC120 inhibits ABA biosynthesis via transcriptional repression of the ABA biosynthetic genes OsNCED3 and OsNCED4.Rice OSMOTIC STRESS/ABA-ACTIVATED PROTEIN KINASE 9(OsSAPK9)physically interacts with OsNAC120 and mediates its phosphorylation,which results in OsNAC120 degradation.ABA treatment ac-celerates OsNAC120 degradation and reduces its transactivation activity.Together,ourndings provide evi-dencethatOsNAC120playscriticalrolesinbalancingGA-mediatedgrowthandABA-induceddroughttolerance in rice.This research will help us to understand the mechanisms underlying the trade-off between plant growth and stress tolerance and to engineer stress-resistant,high-yielding crops.