Green synthesis,characterization,acaricidal,larvacidal,and repellent activities of copper nanoparticles of Astragalus sinicus against Hyalomma anatolicum

Objective:To green synthesize and characterize copper nanoparticles(Cu NPs)using Astragalus sinicus,as well as evaluate the acaricidal,larvacidal,and repellent activities of Cu NPs against Hyalomma anatolicum(H.anatolicum),one of the most prevalent ticks infesting cattle in Saudi Arabia.Methods:Cu NPs were green synthesized by adding the Astragalus sinicus extract to a copper sulfate solution.The acaricidal,larvicidal,and repellent activities of Cu NPs against H.anatolicum were assessed via the adult immersion test,the larval packet test,and the vertical movement behavior of tick larvae,respectively.The effects of Cu NPs on acetylcholinesterase as well as oxidative enzyme activities were examined.Results:The green synthesized Cu NPs displayed a spherical form with a size range of 15-75 nm.After exposure of adult H.anatolicum to different concentrations of Cu NPs,the viability rate of adult H.anatolicum and the mean number,weight,and hatchability of eggs were noticeably reduced,in comparison to the control group(P<0.001).In addition,the viability rate of larvae considerably declined(P<0.001)with the LC_(50)and LC_(90)values of 11.30 and 20.34μg/m L,respectively.The maximum repellent activity of Cu NPs was observed at 50,100,and 200μg/m L with complete repellent activity after 60,120,and 180 min of exposure,respectively.Cu NPs,mainly at 1/2 LC_(50)and LC_(50)concentrations,markedly suppressed the acetylcholinesterase activity of the larval stage of H.anatolicum(P<0.001).Moreover,Cu NPs,mainly at LC_(50)dose,significantly elevated malondialdehyde level while declining glutathione-S-transferase level in H.anatolicum larvae(P<0.001).Conclusions:Cu NPs show potent acaricidal,larvicidal,and repellent activities against adults and larvae of H.anatolicum.However,further studies must be performed to clarify the precise mechanisms and the efficacy of Cu NPs in practical use.

Adaptability Comparison of Chinese Milk Vetch (Astragalus sinicus) Varieties for Double-rice Cropping System in Hunan

Five Chinese milk vetch（Astragalus sinicus） varieties were selected to make a comparison in order to screen effective varieties which could suit for the double-rice cropping system of Hunan Province. The results showed that the growth period of Xiangzi 2 is shorter than that of Xiangfei 2, Xiangfei 3 and Yujiangdaye,and is similar to that of Xinyang Chinese milk vetch. The full-bloom stage of Xiangzi 2 is also similar to Xinyang variety and obviously earlier than that of the other three varieties. The fresh grass yield of Xiangzi 2 in full-bloom stage is 23 842.5kg/hm^2, which increases by 39.9% compared with Xinyang variety. Nitrogen content in the fresh grass of Xiangzi 2 is higher than that of the other four varieties. In conclusion, Xiangzi 2 is an extremely early-blossoming and early-maturing Chinese milk vetch variety with moderate fresh grass yield, high nutrient contents, stable characters and wide adaptability. So, Xiangzi 2 is suitable for planting in double-rice cropping region in Hunan Province and other same latitude regions which have similar ecological conditions.

藻类种类和浓度对中华哲水蚤(Calanus sinicus)摄食和消化酶活性的影响

通过饵料浓度差法在实验条件下研究了不同浓度的金藻、三角褐指藻和巴夫藻对中华哲水蚤(Calanus sinicus)摄食和消化酶活性的影响,结果表明:不同藻类和浓度对中华哲水蚤的摄食有明显的影响。(1)中华哲水蚤对3种饵料藻的摄食存在一饱和浓度,低于饱和浓度,摄食率随着食物浓度的增加而增加;高于饱和浓度,摄食率呈下降趋势。实验浓度下,中华哲水蚤对金藻、三角褐指藻和巴夫藻的最大摄食率分别为4664、6021cellsml-1和4524cellsml-1。滤水率随着食物浓度的增加而呈单一性的下降。(2)中华哲水蚤消化酶活性随藻类种类和浓度的变化而变化。不同藻类和浓度下,昆布多糖酶活性都明显高于麦芽糖酶和纤维二糖酶的活性,而麦芽糖酶活性又稍高于纤维二糖酶的活性。不同藻类喂养条件下,中华哲水蚤3种消化酶的活性发生了不同程度的变化,以巴夫藻喂养时酶活性稍高。

Genetic Variability of Astragalus sinicus L. Based on ISSR Markers

Genetic relationships among 22 accessions of Astragalus sinicus L. col ect-ed from different provinces of China were analyzed by inter-simple sequence repeat （ISSR） markers. The results showed that 10 highly reproducible ISSR fragments a-mong 40 primers were screened. Using these primers, a total of 684 ISSR frag-ments from 500 to 3 000 bp were amplified, and 59.2% of them showed polymor-phic by unweighted pair-group method with arithmetic （UPGMA） analysis. It revealed that the 22 accessions had a similarity range from 0.63 to 0.95, and existed biolog-ical diversities. Based on cluster and principal coordinate analyses, al accessions could be divided into four distinct groups.

Effects of Ploughing Astragalus sinicus at Maturity Stage on Rice Yield and Soil Properties of Paddy Field

[Objective] The effects of ploughing Astragalus sinicus at maturity stage as green manure on paddy soil properties were studied to provide references for ad- vancing the green manure production and field sustainable development. [Methods] A three-year field positioning experiment was carried out. In the first year, five differ- ent levels （0, 2.81, 5.61, 8.42, 11.23 t/hm~） of Astragalus sinicus ploughed at matu- rity stage were designed. And in the next two years, the amounts of ploughed As- tragalus sinicus at maturity stage were based on the natural growth amounts of As- tragalus sinicus at maturity stage of the former year in each plot field. The yields of Astragalus sinicus at maturity stage were estimated and ploughed directly before rice transplanting. Rice yield, soil nutrients, biological properties and water-stable aggre- gates of paddy fields were measured as well. [Results] The effective panicles and rice yields increased significantly after ploughing Astragalus sinicus at maturity stage. Meanwhile, the organic acid content in paddy field increased and the activities of soil phosphatases, invertase and catalase were higher. The soil dissolved organic carbon also increased with the increasing application of green manure. However, excess amount of green manure inhibited the soil microbial biomass carbon content. The macro aggregates and micro aggregates gathered to middle aggregates. [Conclusion] As green manure, the use of Astragalus sinicus at maturity stage could improve soil physiochemical and biological properties, improve soil fertility and increase rice yield significantly. But the ploughing amount of Astragalus sinicus at maturity stage before rice transplanting should be less than 8.42 t/hm2 （dry weight.

Peaked abundance of Calanus sinicus earlier shifted in the Changjiang River (Yangtze River) Estuary:a comparable study between 1959,2002 and 2005

The sea surface temperature （SST） of the East China Sea （ECS） increased in the past decades, which may have a great impact on the ecosystem of the ECS, including the changes in planktonpopulation structure. In this paper, the changes in peaked abundance of Calanus sinicus in the Changjiang River （Yangtze River） Estuary were compared between 1959 and 2002, based on the data collected from the seasonally oceanographic cruises and those performed in spring of 2005. It was much higher in spring compared with that in other seasons both in 1959 and 2002. Furthermore, in spring 2005, the time for occurrence and decrease of the peaked C. sinicus abundance advanced about one month, accompanying the increase in the sea surface water temperature （SST）. It peaked in June and decreased in July in 1959, however, in 2005, it peaked in May and attenuated sharply in early June. The earlier decrease of peaked C. sinicus abundance may further deteriorate the ecosystem in the Changjiang River Estuary and north nearshore of the ECS.

Seasonal distribution of Calanus sinicus (Copepoda,Crustacea) in the East China Sea

On the basis of the four-season investigation in 23°30′ ~ 33°N and 118°30′ ~ 128°E of the East China Sea from 1997 to 2000, the seasonal distribution of Calanus sinicus was studied with aggregation intensity, regression contribution and other statistical methods. It was inferred that C. sinicus＇ s predominance presented from winter to summer, especially in spring and summer, because its dominance amounted to 0.62 and 0.29 respectively. The percent of its abundance in copepod abundance was 76.71% in summer, greater than 66.60% in spring, greater than 19.02% in winter, greater than 4.02% in autumn. The occurrence frequency in winter and spring was 83.08% and 93.89% , higher than that in summer and autumn, 76.71% and 73.87%. Compared with other dominant species of copepods, C. sinicus＇ s contribution to the copepod abundance was obviously greater than that of the other species in winter, summer and spring, but smaller in autumn. C. sinicus tended to have an aggregated distribution. The clumping index peaked in summer （50.19） , followed in spring （19.60） , declined in autumn （13.18） and was the lowest in winter （3.04）. The abundance changed in different seasons and areas, relating to temperature but not salinity in spring and autumn, to salinity but not temperature in summer; to neither temperature nor salinity in winter. In spring and summer, its high abundance area was often located in the mixed water mass formed by the Taiwan Warm Current, the Huanghai Sea Cold Water Mass, the coastal water masses and the Changjiang Dilute Water. In spring and autumn, its abundance was affected by the warm current, as well as the runoff from continental rivers affected it in summer. It can be inferred that C. sinicus was adapted to wide salinity and temperature, as a euryhalinous and eurythermous species in the East China Sea.

Acute Toxicity of Clethodim, Cypermethrin and 2,4-D-butylate to the Larva of Chironomus sinicus

[Objective] The aim of this study was to detect the acute toxicity of clethodim, cypermethrin and 2,4-D-butylate. [Method] Chironomus sinicus larvae were exposed to different concentrations of clethodim, cypermethrin and 2,4-D-butylate. Survival rate, lethal concentration 50 （LC50） and superoxide dismutase （SOD） activity in the homogenate of the larvae were monitored to detect the toxicity of the pesti- cides. [Result] The survival rates of C. sinicus larvae exposed to cypermethrin and 2,4-D-butylate for 12 h were almost unchanged at different concentrations, but de- creased with concentration increasing 48 h later. For each pesticide, the differences in survival rates of C. sinicus larvae at 48 h were significant. The 48 h LC50 of clethodim, cypermethrin and 2,4-D-butylate to C. sinicus larvae were 1.842, 0.150 and 1.999 mg/L, respectively. The acute toxicity of cypermethrin was the highest a- mong the three pesticides and that of 2,4-D-butylate was the lowest. Clethodim sig- nificantly reduced the SOD content in a dose-dependent manner. 2,4-D-butylate also reduced SOD content in C. sinicus larvae, but the reduction was not significantly re- lated to its dosage. However, cypermethrin showed no significant effect on SOD ac- tivity in C. sinicus larvae.

Molecular phylogeography and population genetic structure of the planktonic copepod Calanus sinicus Brodsky in the coastal waters of China

Planktonic copepod Calanus sinicus is the dominant meso-zooplankton in the Northwest Pacific Ocean. To better understand its population dynamics and phylogeographic patterns, 243 C. sinicus individuals were collected from seven locations across the shelf waters of China and its population genetics was studied by mitochondrial DNA cytochrome oxidase I（mtCOI） sequences analyses. Thirty-nine different sequences, or haplotypes, were detected with moderate haplotype diversity（h=0.749） and low nucleotide diversity（π=0.003） for all populations. The evolutionary divergence between geographic populations varied from 0.24% to 0.37%, indicative of very limited genetic differentiation. Visualized minimum spanning network（MSN） and phylogenetic analysis of all the detected haplotypes did not reveal any clear phylogeographic pattern. Furthermore, AMOVA data showed no significant spatial population differentiation existed among the individuals collected across China shelf waters. Pairwise FST values showed that population collected from northwest of the East China Sea（ECS） displayed a low difference to other populations. Mismatch distribution analyses and neutrality tests indicated that C. sinicus might undergo a demographic/population expansion. No significant population genetic structuring was detected, indicating an extensive gene flow among the C. sinicus populations. Our results provide molecular evidence for the hypothesis that C. sinicus in the northwestern South China Sea in winter is transported from the East China Sea and the Yellow Sea by the China Coastal Current during the northeast monsoon period.

Seasonal variation in fatty acid composition of seston and the copepod Calanus sinicus(Brodsky,1962)in Jiaozhou Bay and its trophic implications

The fatty acid compositions of seston and Calanus sinicus were investigated to study trophic relationships in Jiaozhou Bay. Principal component analysis was carried out to ordinate the fatty acid patterns of seston in stations and months. The results showed that diatoms were most abundant in the phytoplankton at station A5 （located in the northwest of the bay： 36~9＇N, 120~20＇E） and least abundant at station D7 （located outside of the bay： 35~59＇N, 120~26＇E）. By contrast, dinoflagellates were most abundant at station D7 and least abundant at station A5. According to the annual variations of 16：1 （o7 and 18：4（o3/ 16：1（o7, diatoms flourished mainly in spring and summer, while dinoflagellates bloomed exclusively in summer. A distinctive feature of the fatty acid composition of C. sinicus was the prevalence of 20：5o3 and 22：6（o3. The higher content of 16：1（o7 over 18：4（o3 in females indicated that diatoms contributed more than dinoflagellates to the diet of C. sinicus. The feeding intensity of C. sinicus on diatoms was higher in spring and autumn than in other seasons. The herbivorous indicators 20：1 and 22：1 were comparatively low, suggesting that besides phytoplankton, C. sinicus might feed on a wider range of particles including organic detritus, bacteria and small copepods.

Changes in the population structure of Calanus sinicus during summer–autumn in the southern Yellow Sea

Calanus sinicus is a calanoid copepod widely distributed in coastal waters of China and Japan, and oversummering strategies may have major impacts on their population dynamics which in turn affect local marine food web structure. The abundance, stage composition, and sex composition of the planktonic copepod C. sinicus were studied from August to October 2002 in the southern Yellow Sea to understand how its population recovers from the over-summering state. Results showed that C. sinicus had low reproduction in August due to high temperature, except in waters near the Cheju Island with rich food and moderate bottom temperature, but the reproduction rates here decreased in September–October as food availability declined. When temperature dropped in September–October, C. sinicus actively propagated in coastal shallow waters. However, reproduction rates of C. sinicus individuals inhabiting the Yellow Sea Cold Water Mass(YSCWM) remained low during the three months of the study. The percentage of C. sinicus females was high during the reproductive period, which suggests that the sex composition of adult C. sinicus may reflect whether or not the population is in the reproductive mode.Numerous fifth copepodite stage(CV) C. sinicus aggregated in the YSCWM in a suspended developmental stage during the three months of this study, and they potentially served as the parental individuals for population development when conditions became optimal for reproduction later in the year.

Lipids and fatty acids in Calanus sinicus during over-summering in the southern Yellow Sea

Over-summering is a crucial period for Calanus sinicus in the southern Yellow Sea,where it is a key member of the zooplankton community.Lipids play an important role in copepod diapause,which is part of their over-summering strategy.We investigated how different fatty acids and lipid classes,including wax esters,changed during over-summering of C.sinicus during three cruises in June and August 2011 and November 2010,corresponding to the pre-,during and post-diapause periods,respectively.Large amounts of lipids were accumulated,mainly wax esters as previously found in C.finmarchicus during its diapause,and most of the storage lipids were used during over-summering.Wax ester polyunsaturated fatty acids(PUFAs) showed the most variation of the fatty acids(FAs),while the percentage composition of FAs in polar lipids was relatively stable.Selective use of wax ester PUFAs has already been shown to play important roles in the winter diapause of Calanus species in other regions,and our FA results show that this is the case for the Yellow Sea Cold Bottom Water(YSCBW) population that diapauses in summer.

Annual variation in Calanus sinicus abundance and population structure in the northern boundary area of the Yellow Sea Cold Water Mass

The Yellow Sea Cold Water Mass （YSCWM） was suggested as an over-summering site of the dominant copepod species Calanus sinicus in coastal Chinese seas. Population abundance and structure were investigated by monthly sampling along three transects across the northern boundary of the YSCWM during 2009-2010. Results show that thermal stratification existed from June to October and that the vertical thermal difference increased with depth. Generally, total abundance was lowest in October and highest in June, and the female/male sex ratio was highest in February and lowest in August. Evident spatial differences in abundance were observed during the existence of the YSCWM. In June, total abundance averaged 158.8 ind/m~ at well-stratified stations, and 532.1 ind/m3 at other stations. Similarly, high abundances of 322.0 and 324.4 ind/m3 were recorded from July to August inside the YSCWM, while the abundance decreased from 50.4 to 1.9 ind/m3 outside the water mass. C. sinicus distribution tended to even out over the study area in September when the YSCWM disappeared. We believe that the YSCWM may retard population recruitment in spring and preserve abundant cohorts in summer. The summer population was transported to neritic waters in autumn. In addition to low temperatures, stable vertical structure was also an essential condition for preservation of the summer population. C. sinicus can survive the summer in marginal areas in high abundance, but the population structure is completely different in terms of C5 proportion and sex ratio.

Photobehaviors ofthe calanoid copepod Calanus sinicus from the Yellow Sea to visible and UV-B radiation as a function of wavelength and intensity

The effects of wavelength-specific visible light, white light, and ultraviolet-B (UV-B, 280- 315 nm) on selected behaviors, grazing rate, spawning rate, and hatching rate of the marine copepod Calanus sinicus collected from the Yellow Sea were studied. Calanus sinicus placed in a partitioned experimental system responded positively phototaxis to blue-cyan and yellow light but negatively to orange light and UVB. No obvious dodge activity was found among C. sinicus irradiated with <0.005 mW/cm^2 UV-B. Under 0.20, 0.30 and 0.50 mW/cm^2 UV-B radiation, the lethal half times of individuals were 30.47, 2.86, and 1.96 h, respectively. Grazing of C. sinicus was restrained at >0.10 mW/cm^2 UV-B, whereas yellow-red light stimulated grazing. Egg production rate was highest at a white-light intensity of 1.58 mW/cm^2, with an average rate of 10.04 eggs/(female·d). These results are consistent with the observed phenomenon that C. sinicus in the Yellow Sea mostly spawn near dawn. Our results indicate that light intensity and spectrum are important factors affecting the diel vertical migration of C. sinicus under natural conditions in the Yellow Sea.

Impact of microzooplankton and Calanus sinicus(Brodsky,1962) on phytoplankton in the Yellow Sea during early summer

Dilution incubations and Calanus sinicus addition incubations were simultaneously conducted at five stations in the Yellow Sea in June of 2004 to evaluate the impact of microzooplankton and Calanus sinicus on phytoplankton based on the Chlorophyll a(Chl-a) levels.The Chl-a growth rates(k) ranged from 0.60-1.67 d-1,while microzooplankton grazed the Chl-a at rates(g) of 0.29-0.62 d-1.The addition of C.sinicus enhanced the Chl-a growth rate(Z) by 0.004-0.037 d-1 ind.-1 L.C.sinicus abundance ranged from 84.1-160.9 ind.m-3,which occupied 90.7%-99.1% of the copepod(>500 μm) population.The in-situ increase in phytoplankton by C.sinicus community was estimated to be 0.000 4-0.005 9 d-1.These results showed that microzooplankton were the main grazers of phytoplankton,while C.sinicus induced a slight increase in the levels of phytoplankton.

Annual Occurrence of Calanus sinicus Carcasses in the Jiaozhou Bay and the Adjacent Waters

The dead proportion of a calanoid copepod Calanus sinicus population was investigated monthly with neutral red staining method at 12 stations in the Jiaozhou Bay and the adjacent waters from December 2008 to November 2009. C. sinicus could be observed through the whole year, with an evident numerical peak from February to April and an extremely low abundance in summer. Annual variation of the dead proportion differed greatly between adult females and copepodites. Dead females were observed only in the southern part and outside the bay sporadically in five months, when the egg production was the most active. Dead proportion of females was usually less than 5%. Dead copepodites could be observed in all but three months in summer in the whole study area, and the proportion varied between 3.8% – 18.2%. Death percentage of copepodites increased significantly in the northern part in January and June, when water temperature exceeded it's favorable limits;however, the fluctuated salinity had no significant effect on the survival of both females and copepodites. Thus the dead proportion of C. sinicus was relatively low in the Jiaozhou Bay, while difference could be observed between females and copepodites. Dead copepodites were common in all samples, but dead females were presented mainly as ‘reproduction cost' during generation alternation.

Effect of diurnal temperature difference on lipid accumulation and development in Calanus sinicus(Copepoda:Calanoida)

Calanus sinicus,the dominant copepod in the Yellow Sea,develops a large oil sac in late spring to prepare for over-summering in the Yellow Sea Cold Water Mass(YSCWM).The lipid accumulation mechanism for the initiation of over-summering is unknown.Here,we cultured C3 copepodites at four constant temperatures(10,13,16,and 19℃) and at three temperature regimes that mimicked the temperature variations experienced during diurnal vertical migration(10-13℃,10-16℃,and 10-19℃) for 18 days to explore the effects of temperature differences on copepod development and lipid accumulation.C.sinicus stored more lipid at low than at high temperatures.A diurnal temperature difference(10-16℃ and 10-19℃)promoted greater lipid accumulation(1.9-2.1 times) than a constant temperature of either 16℃ or 19℃,by reducing the energy cost at colder temperatures and lengthening copepodite development.Thereafter,the lipid reserve supported gonad development after final molting.Only one male developed in these experiments.This highly female-skewed sex ratio may have been the result of the monotonous microalgae diet fed to the copepodites.This study provides the first evidence that diurnal temperature differences may promote lipid accumulation in C.sinicus,and provides a foundation for future investigations into the mechanisms involved in over-summering in the YSCWM.

Factors aff ecting lipid and fatty acid composition of Calanus sinicus in the Yellow Sea and the East China Sea in spring

The factors aff ecting lipid and fatty acid composition of copepod Calanus sinicus in the Yellow Sea(YS)and the East China Sea(ECS)were examined in this study.In spring,there were signifi cant diff erences between these two regions for both environmental conditions and food availability.Such regional diff erence signifi cantly infl uenced the lipid and fatty acid profi les of C.sinicus.Our results show that C.sinicus has a higher lipids content in ECS,especially for wax ester and triglyceride lipids,indicating a more active and effi cient predation.According to BIO-ENV analysis,the variation of lipids profi les may be infl uenced majorly by water temperature.Moreover,the fatty acids(FAs)profi les of C.sinicus were also diff erent between YS and ECS,especially in the four major contributors,C22꞉1ω11,eicosapentaenoic acid(EPA),docosahexenoic acid(DHA),and C20꞉1ω9.The considerable amounts of self-biosynthesized FAs of herbivorous copepod(C22꞉1ω11 and C20꞉1ω9)and low DHA/EPA ratio may indicate that C.sinicus in ECS feed mainly on phytoplankton comparing to those in YS.The fatty acid profi les of C.sinicus were aff ected by the diff erences in food availability.

Diel vertical migration of the copepod Calanus sinicus before and during formation of the Yellow Sea Cold Bottom Water in the Yellow Sea

To understand the effects of the Yellow Sea Cold Bottom Water （YSCBW） on the diel vertical migration （D- VM） of the copepod Calanus sinicus, we surveyed vertical distribution of C. sinicus at a fixed station in the Yellow Sea before （spring） and during （summer） formation of the YSCBW. Cold water （〈10℃） was observed in the bottom layer when the water column was thermally stratified in summer, but the water column was thermally well-mixed in spring 2010. Samples were collected from five different layers at 3-h intervals using an opening-closing net. Adult females （1-155 ind./m3） showed a clear normal DVM pattern throughout the entire water column in spring, whereas adult males did not migrate. DVM of copepodite V （CV） individuals was not clear, but the maximum abundance of CI-CIV occurred consistently in the upper 10-20 m layer, where there was a high concentration of chlorophyll-a （Chl-a） （0.49-1.19μg/L）. In summer, weak DVM was limited to cold waters beneath the thermocline for adult females （〈30 ind./m3）, but not for adult males. The maximum abundance of CI-CIV also occurred consistently in the subsurface layer （20-40 m） together with high concentrations of Chl-a （0.81-2.36 μg/L）. CV individuals （1-272 ind./m3） moved slightly upward noc- turnally to the near-surface layer （10-20 m）, where the average temperature was 25.74℃, but they were not found in the surface layer （0-10 m; 28.31℃）. These results indicate that the existence of the YSBCW affected food availability at depth and the vertical temperature distribution, leading to variation in the amplitude and shape of stage-specific vertical distributions （CI to adults） in C. sinicus before and during the formation of cold waters in the Yellow Sea during the study period.

Vacuolar phosphate transporters account for variation in phosphate accumulation in Astragalus sinicus cultivars

Astragalus sinicus is a commonly used legume green manure that fixes atmospheric N2 and accumulates mineral nutrients and organic substances that are beneficial to soils and subsequent crops.However,little is known about genotypic variation in,and molecular mechanisms of,Pi(phosphate)uptake and storage in A.sinicus.We recorded the morphological responses of six A.sinicus cultivars from four regions of China to external Pi application and measured their Pi accumulation.We identified full-length transcripts of Pi-signaling and Pi-homeostasis regulators by sequencing and measured the expression level of these genes by qRT-PCR.The major components in Pi signaling and Pi homeostasis were largely conserved between A.sinicus and the model species rice and Arabidopsis.Different A.sinicus varieties responded differently to low-phosphorus(P)stress,and their Pi accumulation was positively correlated with the expression of vacuolar Pi influx gene(SYG1/PHO81/XPR1-MAJOR FACILITATOR SUPERFAMILY(SPX-MFS)-TYPE PROTEIN)AsSPXMFS2 and negatively correlated with the expression of the vacuolar Pi efflux gene(VACUOLAR Pi EFFLUX TRANSPORTER)AsVPE1.We identified key Pi-signaling and Pihomeostasis regulators in A.sinicus.The expression of vacuolar Pi transporter genes could be used as an index to select A.sinicus accessions with high Pi accumulation.