Induction of Root Hair Growth in a Phosphorus-Buffered Culture Solution

A system to control the release of phosphate in water was successfully established, based on solubility product of [Ca^2＋] and [PO4^3-] using tricalcium phosphate as P source in the hydroponic solution, and adding CaCl2 for supplementing extra Ca^2＋. The system, similar to soil solutions, was a P nutrient buffer solution with very low bioavailable P. The buffer solution induced the roots of both monocotyledon and dicotyledon species to grow abundant root hairs, 3 mm in maximum length. The monocotyledons were corn （Zea mays L.） （var. Yellow Rose）, wheat （Triticum aestivum L.） （var. Yanzhong 144）, Triticale secale L. （vat. Jingsong 5）, and ryegrass （Lolium rigidum L.） （var. Ruanni）, and the dicotyledons were Arabidopsis thaliana L. （var. Columbia）, white clover （Trifolium repens） （var. Kopu）, Lotus （Lotus peduncucatus Cav. Luliginosus Schkuhr） （var. Grasslands Maku）. For these species we proved that the root environment controls the induction of root hair formation. However, the hydroponic buffer solution failed to induce root hairs on the roots of onion （Allium cepa L.）. Other investigators have concluded that corn does not form root hairs in hydroponics, but abundant long root hairs on corn were induced by this buffer system. The roots with abundant long root hairs are called ＂hedgehog roots＂ because they have hairs everywhere just like a hedgehog.

An alfalfa MYB-like transcriptional factor MsMYBH positively regulates alfalfa seedling drought resistance and undergoes MsWAV3-mediated degradation

Drought is a major threat to alfalfa(Medicago sativa L.)production.The discovery of important alfalfa genes regulating drought response will facilitate breeding for drought-resistant alfalfa cultivars.Here,we report a genome-wide association study of drought resistance in alfalfa.We identified and functionally characterized an MYB-like transcription factor gene(MsMYBH),which increases the drought resistance in alfalfa.Compared with the wild-types,the biomass and forage quality were enhanced in MsMYBH overexpressed plants.Combined RNA-seq,proteomics and chromatin immunoprecipitation analysis showed that MsMYBH can directly bind to the promoters of MsMCP1,MsMCP2,MsPRX1A and MsCARCAB to improve their expression.The outcomes of such interactions include better water balance,high photosynthetic efficiency and scavenge excess H_(2)O_(2)in response to drought.Furthermore,an E3 ubiquitin ligase(MsWAV3)was found to induce MsMYBH degradation under long-term drought,via the 26S proteasome pathway.Furthermore,variable-number tandem repeats in MsMYBH promoter were characterized among a collection of germplasms,and the variation is associated with promoter activity.Collectively,our findings shed light on the functions of MsMYBH and provide a pivotal gene that could be leveraged for breeding drought-resistant alfalfa.This discovery also offers new insights into the mechanisms of drought resistance in alfalfa.

Dietary crude protein and protein solubility manipulation enhances intestinal nitrogen absorption and mitigates reactive nitrogen emissions through gut microbiota and metabolome reprogramming in sheep

Dietary nutrient manipulation(e.g.protein fractions)could lower the environmental footprints of ruminants,especially reactive nitrogen(N).This study investigated the impacts of dietary soluble protein(SP)levels with decreased crude protein(CP)on intestinal N absorption,hindgut N metabolism,fecal microbiota and metabolites,and their linkage with N metabolism phenotype.Thirty-two male Hu sheep,with an age of six months and an initial BW of 40.37±1.18 kg,were randomly assigned to four dietary groups.The control diet(CON),aligning with NRC standards,maintained a CP content of 16.7%on a dry matter basis.Conversely,the experimental diets(LPA,LPB,and LPC)featured a 10%reduction in CP compared with CON,accompanied by SP adjustments to 21.2%,25.9%,and 29.4%of CP,respectively.Our results showed that low-protein diets led to significant reductions in the concentrations of plasma creatinine,ammonia,urea N,and fecal total short-chain fatty acids(SCFA)(P<0.05).Notably,LPB and LPC exhibited increased total SCFA and propionate concentrations compared with LPA(P<0.05).The enrichment of the Prevotella genus in fecal microbiota associated with energy metabolism and amino acid(AA)biosynthesis pathways was evident with SP levels in low-protein diets of approximately 25%to 30%.Moreover,LPB and LPC diets demonstrated a decrease in fecal NHþ4 eN and NO2 eN contents as well as urease activity,compared with CON(P<0.05).Concomitantly,reductions in fecal glutamic acid dehydrogenase gene(gdh),nitrite reductase gene(nirS),and nitric oxide reductase gene(norB)abundances were observed(P<0.05),pointing towards a potential reduction in reactive N production at the source.Of significance,the up-regulation of mRNA abundance of AA and peptide transporters in the small intestine(duodenum,jejunum,and ileum)and the elevated concentration of plasma AA(e.g.arginine,methionine,aspartate,glutamate,etc.)underscored the enhancement of N absorption and N efficiency.In summary,a 10%reduction in CP,coupled with an SP level of approximately 25%to 30%,demonstrated the potential to curtail reactive N emissions through fecal Prevotella enrichment and improve intestinal energy and N utilization efficiency.

The power of phenomics:Improving genebank value and utility

Genebanks are considered the"crown jewels"of research organizations,as they safeguard valuable plant genetic resources and address the emerging challenges posed by climate-related constraints(Anglin et al.,2018).Currently,7.4 million accessions have been conserved in 1750 gene banks worldwide.Of these,only 10%are being used for crop improvement(Commission on Genetic Resources for Food and Agriculture,2010).The limited availability of passport data and the challenge of characterizing trait attributes of accessions at large scale are some of the challenges to relate their true value(Tadesse et al.,2019).Obtaining traits such as agronomic or nutritional characteristics requires extensive field phenotyping and multiple site testing over several seasons.This will create value with accurate evaluation of genotype-by-environmental variation in a given trait.The use of low-cost high-throughput phenotyping(HTP)methods to characterize the genotypic and phenotypic representations of genebank genetic resources,otherwise known as genebank phenomics,will help in understanding crops'potential for use in breeding programs with desirable traits.

Antifungal activity and phytochemical investigation of the asexual endophyte of Epichloё sp. from Festuca sinensis

Dear Editor,Much research is now being conducted on grasses-Epichloe associations. The asexual Epichloe species have attracted much attention over the past 30 years as they can provide benefits to important forage grasses, in particular perennial ryegrass （Lolium perenne）, annual ryegrass （L. multiflorum）, tall fescue （Festuca arundinacea）, and meadow rescue （F. pratense） [1]. Some findings epichloe endophyte （E＋） are suggest that grasses with an more resistant to pathogenic fungi than uninfected （E-） grass [1]. Tests using detached and attached leaves have shown that the size of lesions caused by pathogenic fungi are smaller on E＋ leaves than on E- leaves [2]. Products inhibitory to plant pathogenic fungi are produced by epichloe endophytes growing saprotrophically [3,4].

Application of geovisual analytics to modelling the movements of ruminants in the rural landscape using satellite tracking data

Geovisual analytics provides a framework for the development of decision support tools for landscape design,analysis and optimisation.An important application is modelling the spatial-temporal movements of ruminants and their grazing behaviour using global positioning system(GPS)collar units.This study describes the mapping and analysis of spatial distributions of animal waste products(which correlate with farm nitrogen[N]emissions)and also determination of animal feeding preferences(which correlate with animal welfare and production).Segmentation of local regions of animal N emissions provides support in meeting targets for local and international N leaching and greenhouse gas emissions.An agent-based model was used for prescreening in order to gain insights into the clustering behaviour of sheep during feeding activities.Subsequent spatial analysis demonstrated that livestock excreta are not always randomly located,but concentrated around highly localised animal gathering points,separated by the nature of the excretion.In a separate study,the statistical significance of feeding choices was determined by testing a null hypothesis on animal boundary transitions between adjacent pastures using the binomial approximation.The analysis also included compensation for the precision of the GPS sensor,which produced a fuzzy decision boundary.

Erratum to:The fungal endophyte Epichloë gansuensis increases NaCl-tolerance in Achnatherum inebrians through enhancing the activity of plasma membrane H^(+)-ATPase and glucose-6-phosphate dehydrogenase

1.In the results,we mistakenly described the information of Figure 9B.The correct sentence should be“The factor 1 and factor 2 explained 71.30%and 16.68%of the total variance,respectively.The 0 mmol L^(-1) NaCl concentration showed the highest contribution(29.95%)to factor 1 in roots of E+plants,and 200 mmol L^(-1) NaCl concentration was significantly loaded(45.95%)on factor 2 in roots of E+plants(Figure 9B).”

The fungal endophyte Epichloëgansuensis increases NaCltolerance in Achnatherum inebrians through enhancing the activity of plasma membrane H^(+)-ATPase and glucose-6-phosphate dehydrogenase

Salt stress negatively affects plant growth,and the fungal endophyte Epichloëgansuensis increases the tolerance of its host grass species,Achnatherum inebrians,to abiotic stresses.In this work,we first evaluated the effects of E.gansuensis on glucose-6-phosphate dehydrogenase(G6PDH)and plasma membrane(PM)H^(+)-ATPase activity of Achnatherum inebrians plants under varying NaCl concentrations.Our results showed that the presence of E.gansuensis increased G6PDH,PMH^(+)-ATPase,superoxide dismutase and catalase activity to decrease O2•^(–),H_(2)O_(2)and Na^(+)contents in A.inebrians under NaCl stress,resulting in enhanced salt tolerance.In addition,the PM NADPH oxidase activity and NADPH/NADP+ratios were all lower in A.inebrians with E.ganusensis plants than A.inebrians plants without this endophyte under NaCl stress.In conclusion,E.gansuensis has a positive role in improving host grass yield under NaCl stress by enhancing the activity of G6PDH and PM H^(+)-ATPase to decrease ROS content.This provides a new way for the selection of stress-resistant and high-quality forage varieties by the use of systemic fungal endophytes.