Chlorine-Substituent Regulation in Dopant-Free Small-Molecule Hole-Transport Materials Improves the Effi ciency and Stability of Inverted Perovskite Solar Cells

Although doped hole-transport materials(HTMs)off er an effi ciency benefi t for perovskite solar cells(PSCs),they inevi-tably diminish the stability.Here,we describe the use of various chlorinated small molecules,specifi cally fl uorenone-triphenylamine(FO-TPA)-x-Cl[x=para,meta,and ortho(p,m,and o)],with diff erent chlorine-substituent positions,as dopant-free HTMs for PSCs.These chlorinated molecules feature a symmetrical donor-acceptor-donor structure and ideal intramolecular charge transfer properties,allowing for self-doping and the establishment of built-in potentials for improving charge extraction.Highly effi cient hole-transfer interfaces are constructed between perovskites and these HTMs by strategi-cally modifying the chlorine substitution.Thus,the chlorinated HTM-derived inverted PSCs exhibited superior effi ciencies and air stabilities.Importantly,the dopant-free HTM FO-TPA-o-Cl not only attains a power conversion effi ciency of 20.82% but also demonstrates exceptional stability,retaining 93.8%of its initial effi ciency even after a 30-day aging test conducted under ambient air conditions in PSCs without encapsulation.These fi ndings underscore the critical role of chlorine-substituent regulation in HTMs in ensuring the formation and maintenance of effi cient and stable PSCs.

Phosphorylation of a wheat aquaporin at two sites enhances both plant growth and defense

Eukaryotic aquaporins share the characteristic of functional multiplicity in transporting distinct substrates and regulating various processes,but the underlying molecular basis for this is largely unknown.Here,we report that the wheat(Triticum aestivum)aquaporin TaPIP2;10 undergoes phosphorylation to promote photosynthesis and productivity and to confer innate immunity against pathogens and a generalist aphid pest.In response to elevated atmospheric CO_(2)concentrations,TaPIP2;10 is phosphorylated at the serine residue S280 and thereafter transports CO_(2)into wheat cells,resulting in enhanced photosynthesis and increased grain yield.In response to apoplastic H_(2)O_(2) induced by pathogen or insect attacks,TaPIP2;10 is phosphorylated at S121 and this phosphorylated form transports H_(2)O_(2) into the cytoplasm,where H_(2)O_(2)intensifies host defenses,restricting further attacks.Wheat resistance and grain yield could be simultaneously increased by TaPIP2;10 overexpression or by expressing a TaPIP2;10 phosphomimic with aspartic acid substitutions at S121 and S280,thereby improving both crop productivity and immunity.

The bacterial effector AvrRxo1 inhibits vitamin B6 biosynthesis to promote infection in rice

Xanthomonas oryzae pv.oryzicola(Xoc),which causes rice bacterial leaf streak,invades leaves mainly through stomata,which are often closed as a plant immune response against pathogen invasion.How Xoc overcomes stomatal immunity is unclear.Here,we show that the effector protein AvrRxo1,an ATPdependent protease,enhances Xoc virulence and inhibits stomatal immunity by targeting and degrading rice OsPDX1(pyridoxal phosphate synthase),thereby reducing vitamin B6(VB6)levels in rice.VB6 is required for the activity of aldehyde oxidase,which catalyzes the last step of abscisic acid(ABA)biosynthesis,and ABA positively regulates rice stomatal immunity against Xoc.Thus,we provide evidence supporting a model in which a major bacterial pathogen inhibits plant stomatal immunity by directly targeting VB6 biosynthesis and consequently inhibiting the biosynthesis of ABA in guard cells to open stomata.Moreover,AvrRxo1-mediated VB6 targeting also explains the poor nutritional quality,including low VB6 levels,of Xoc-infected rice grains.

Multiple forms of vitamin B_(6) regulate salt tolerance by balancing ROS and abscisic acid levels in maize root

Salt stress causes osmotic stress,ion toxicity and oxidative stress,inducing the accumulation of abscisic acid(ABA)and excessive reactive oxygen species(ROS)production,which further damage cell structure and inhibit the development of roots in plants.Previous study showed that vitamin B_(6)(VB_(6))plays a role in plant responses to salt stress,however,the regulatory relationship between ROS,VB_(6) and ABA under salt stress remains unclear yet in plants.In our study,we found that salt stress-induced ABA accumulation requires ROS production,in addition,salt stress also promoted VB_(6)(including pyridoxamine(PM),pyridoxal(PL),pyridoxine(PN),and pyridoxal 5′-phosphate(PLP))accumulation,which involved in ROS scavenging and ABA biosynthesis.Furthermore,VB_(6)-deficient maize mutant small kernel2(smk2)heterozygous is more susceptible to salt stress,and which failed to scavenge excessive ROS effectively or induce ABA accumulation in maize root under salt stress,interestingly,which can be restored by exogenous PN and PLP,respec-tively.According to these results,we proposed that PN and PLP play an essential role in balancing ROS and ABA levels under salt stress,respectively,it laid a foundation for VB_(6) to be better applied in crop salt resistance than ABA.