Population shrinkage of alpine cushion plants with ongoing climate warming has been empirically confirmed.Since cushion plants play important roles in sustaining alpine plant community and ecosystem functions,their po...Population shrinkage of alpine cushion plants with ongoing climate warming has been empirically confirmed.Since cushion plants play important roles in sustaining alpine plant community and ecosystem functions,their population dynamics may directly influence the future alpine ecosystems.However,little is known about how climate warming affect cushion population recruitment,especially at early life-history stages.In this study,we conducted a laboratory simulation of climate warming to detect the effects of warming temperature and associated moisture and light changes on seed germination and seedling growth of the typical alpine cushion plant Arenaria oreophila.Results suggested that increasing temperature indeed exerted strong constraints on the population recruitment processes.Specifically,increased temperatures could quickly initialize seed germination(4e6 days at higher temperatures vs.29 e32 days at low temperature,respectively,after sowing),accelerate them to reach the maximum germination percentage(9e19 days at higher temperatures vs.57e86 days at low temperature,respectively,after sowing)and significantly accelerate seedling growth rate.However,higher temperatures accelerated seedling mortality(more than 80%).In addition,lower light availability also increased seedling mortality though it could generally increase the final seed germination percentage.The effects of water might be dependent on temperature and light.All results suggested that cushion A.oreophila is quite sensitive to climate warming which strongly constrains its seedling establishment process.We,therefore,speculate that the continuing climate warming in future will exert uncertain risks in the persistence of cushion A.oreophila,possibly by constraining the process of seedling recruitments.展开更多
The ubiquitous adoption of mobile devices as essential platforms for sensitive data transmission has heightened the demand for secure client-server communication.Although various authentication and key agreement proto...The ubiquitous adoption of mobile devices as essential platforms for sensitive data transmission has heightened the demand for secure client-server communication.Although various authentication and key agreement protocols have been developed,current approaches are constrained by homogeneous cryptosystem frameworks,namely public key infrastructure(PKI),identity-based cryptography(IBC),or certificateless cryptography(CLC),each presenting limitations in client-server architectures.Specifically,PKI incurs certificate management overhead,IBC introduces key escrow risks,and CLC encounters cross-system interoperability challenges.To overcome these shortcomings,this study introduces a heterogeneous signcryption-based authentication and key agreement protocol that synergistically integrates IBC for client operations(eliminating PKI’s certificate dependency)with CLC for server implementation(mitigating IBC’s key escrow issue while preserving efficiency).Rigorous security analysis under the mBR(modified Bellare-Rogaway)model confirms the protocol’s resistance to adaptive chosen-ciphertext attacks.Quantitative comparisons demonstrate that the proposed protocol achieves 10.08%–71.34%lower communication overhead than existing schemes across multiple security levels(80-,112-,and 128-bit)compared to existing protocols.展开更多
Nondestructive measurement technology of phenotype can provide substantial phenotypic data support for applications such as seedling breeding,management,and quality testing.The current method of measuring seedling phe...Nondestructive measurement technology of phenotype can provide substantial phenotypic data support for applications such as seedling breeding,management,and quality testing.The current method of measuring seedling phenotypes mainly relies on manual measurement which is inefficient,subjective and destroys samples.Therefore,the paper proposes a nondestructive measurement method for the canopy phenotype of the watermelon plug seedlings based on deep learning.The Azure Kinect was used to shoot canopy color images,depth images,and RGB-D images of the watermelon plug seedlings.The Mask-RCNN network was used to classify,segment,and count the canopy leaves of the watermelon plug seedlings.To reduce the error of leaf area measurement caused by mutual occlusion of leaves,the leaves were repaired by CycleGAN,and the depth images were restored by image processing.Then,the Delaunay triangulation was adopted to measure the leaf area in the leaf point cloud.The YOLOX target detection network was used to identify the growing point position of each seedling on the plug tray.Then the depth differences between the growing point and the upper surface of the plug tray were calculated to obtain plant height.The experiment results show that the nondestructive measurement algorithm proposed in this paper achieves good measurement performance for the watermelon plug seedlings from the 1 true-leaf to 3 true-leaf stages.The average relative error of measurement is 2.33%for the number of true leaves,4.59%for the number of cotyledons,8.37%for the leaf area,and 3.27%for the plant height.The experiment results demonstrate that the proposed algorithm in this paper provides an effective solution for the nondestructive measurement of the canopy phenotype of the plug seedlings.展开更多
Seaweed extract contains plant growth regulators and bio-stimulants that enhance plant growth and development.In Bangladesh,winter rice(Boro rice)in the nursery bed often shows poor seed emergence and weak seedling gr...Seaweed extract contains plant growth regulators and bio-stimulants that enhance plant growth and development.In Bangladesh,winter rice(Boro rice)in the nursery bed often shows poor seed emergence and weak seedling growth due to low temperature.This problem can be addressed by using seaweed extract as a seed priming agent and bio-stimulant.The objective of this study was to evaluate the effectiveness of seaweed extract(Crop Plus)on seed emergence,seedling growth,and vigor of winter rice in the nursery.Two experiments were conducted at Bangladesh Agricultural University using BRRI dhan89.The laboratory experiment consisted of 17 treatments combining three concentrations of Crop Plus(5000,10,000 and 15,000 ppm)and four priming durations(6,12,18,and 24 h),along with hydro-priming and a no priming as control.Seed priming with 15,000 ppm for 24 h produced the highest germination percentage and superior seedling growth traits.The nursery bed experiment comprised 11 treatments combining two doses(1 mL m^(−2)and 2 mL m^(−2))of Crop Plus and five different foliar application schedules,along with a control.All treatments outperformed the control,with the best results from Crop Plus@2 mL m^(−2)applied at 20 and 30 days after sowing(DAS).Overall,the treatment involving seed priming with 15,000 ppm seaweed extract for 24 h,followed by nursery application at 2 mL m^(−2)at 20 and 30 DAS,resulted in higher germination and improved early growth of winter rice.However,further validation across multiple locations,seasons,and rice cultivars is recommended.展开更多
Wind disturbance has emerged as a potential eco-friendly method for seedling cultivation.In this study,an electromechanical device was designed and built to investigate the effects of airflow on the micro-environment ...Wind disturbance has emerged as a potential eco-friendly method for seedling cultivation.In this study,an electromechanical device was designed and built to investigate the effects of airflow on the micro-environment and physiological activities of tomato seedlings in seedbeds by controlled experiments.The results indicated that airflow could enhance CO_(2) concentration near the seedling canopy,accelerate water evaporation from the seedling substrate,and reduce fluctuations in the temperature and humidity in microclimate.The photosynthetic rates of leaves at the 4th,7th,and 10th positions in seedlings subjected to airflow increased by 25.04%,8.23%,and 8.47%,respectively,whereas the transpiration rates increased by 15.59%,22.28%,and 13.26%,respectively when compared to the control group.Additionally,the strong seedling index of seedlings treated with airflow and exogenous iron element increased by 26.02%and 31.5%,respectively.Compared to seedlings treated with exogenous iron element,the geometric mean diameter of the pith tissue cells in the stems of seedlings subjected to airflow disturbance was reduced by approximately 18.66%,while the elastic modulus and bending strength of the stems increased by 10.01%and 5.89%,respectively.Similarly,the volume of root tissue cells decreased by 19.22%,but the elastic modulus of the roots increased by 6.46%.This study confirms that airflow significantly enhances seedling resilience to abiotic stress,yielding similar or better outcomes than exogenous iron application.It provides both theoretical and practical support for using airflow disturbance as a green technology for cultivating robust seedlings.展开更多
When making assessments of forest resources,there is nearly ubiquitous interest in quantifying current status and trends in tree biomass and carbon stocks.While important at various spatial scales,typical estimations ...When making assessments of forest resources,there is nearly ubiquitous interest in quantifying current status and trends in tree biomass and carbon stocks.While important at various spatial scales,typical estimations pertinent to broad forest management and policy issues are conducted for large areas such as state,regional,and national perspectives.These assessments are usually accomplished using large-area forest inventory data collected by National Forest Inventory(NFI)programs.While NFI efforts commonly collect size data for individual trees,there is often limited information for tree seedlings,e.g.,frequency by species.To fully describe the tree population across the entire range of sizes present,this study proposes methods to predict individual seedling groundline diameter and height using models developed from trees having a diameter at breast height(DBH)less than 7.62 cm.These attributes are subsequently used for the prediction of seedling stem volume,total aboveground biomass,and carbon content.The results suggest a smooth transition in tree attributes as size increases to where direct measurement of individual trees and prediction of their volume,biomass,and carbon are implemented as part of standard inventory protocols.Analyses including the full spectrum of tree sizes show that seedlings contribute roughly 0.6%–0.7%of the total tree volume/mass.This additional suite of information provides opportunities for more holistic assessments across the full spectrum of the tree resource or for specialized subdomains that include the seedling component.展开更多
Elongations of coleoptile and mesocotyl are related directly to rice seedling establishment in soil and height of plant is related to lodging in rice production. Twelve typical rice cultivars with different lengths of...Elongations of coleoptile and mesocotyl are related directly to rice seedling establishment in soil and height of plant is related to lodging in rice production. Twelve typical rice cultivars with different lengths of coleoptile and mesocotyl (long, medium and short) were selected by screening the lengths of coleoptile and mesocotyl in 1500 accessions. The seedling establishments of these typical cultivars were compared under the combinations of different sowing depths and flooding durations, and two semi-dwarf varieties (G140, Zhong 96-21) with good seedling establishments and optimum mesocotyl lengths were found. The length of mesocotyl was completely fitted negative binomial distribution and the length of coleoptile was nearly fitted Iognormal distribution. Analysis of the relationships among mesocotyl, coleoptile, seeding depth, flooding duration, and their interactions to seedling establishment percentage showed that there existed significant relations among mesocotyl, coleoptile, mesocotyl x coleoptile, seeding depth, flooding duration and mesocotyl x sowing depth in the experiment for seedling establishment.展开更多
Manglietia patungensis is an endangered species distributed aggregately in evergreen broad-leaved forest communities in Southwest China. A controlling experiment was employed to test the effects of soil type and shade...Manglietia patungensis is an endangered species distributed aggregately in evergreen broad-leaved forest communities in Southwest China. A controlling experiment was employed to test the effects of soil type and shade degree on seed germination and seedling establishment by using four soil types and three shade treatments with five replicates. Results showed that the germination rate of M. patungensis seeds was relatively low ranging from 19% to 31%. Shade degree and soil type had no significant effect on seed germination rate, but influenced germination dynamics. Both shade degree and soil type treatments significantly affected seedling survival and seedling growth. Seedling survival rate increased with increasing light density. Increased light also promoted biomass accumulation and root development of seedlings. The biomass of the seedlings under full light condition increased 72% comparing with the seedlings under 80% shade degree. Root depth, root area and cross number increased with the increase of light density. Seedlings on farmland soil survived better than that on other three kinds of soil. The seedling survival rate in the farmland soil reached 91.4%, but was reduced to 80.3%, 78.0% and 52.8% in old-field soil, sandy soil and forest soil respectively. Total biomass, aboveground biomass and root biomass of seedlings in forest soil was the highest, followed by seedlings in sandy and old-field soils respectively, and seedlings in farmland soil ranked the least. Some suggestions were finally put forward for the conservation of M. patungensis based on the research results.展开更多
Seeds are a source of organic (carbon, C) and mineral (nitrogen, N and phosphorus, P) nutrients for the growing seedling. There is much information on seed mass and N and P contents, and the relationship between these...Seeds are a source of organic (carbon, C) and mineral (nitrogen, N and phosphorus, P) nutrients for the growing seedling. There is much information on seed mass and N and P contents, and the relationship between these and seedling mass. Within the world’s temperate regions, these collectively show that N and P concentrations remain constant or rise with increase in seed mass and that seeds are larger and more nutrient-enriched in poorer soils. Seed N and P were more important than seed C in accounting for seedling mass in 85% of studies we assessed. In nutrient- and water-limited environments that are not light-limited, large seeds routinely provision the seedling with N and P that enhance C-fixation and thus general growth in the first wet season. This system is so efficient that growth response to soil nutrients may be negligible in first-year seedlings arising from seeds > 15 mg mass, N content > 5 mg and P content > 1.6 mg. The elongating taproot system absorbs nutrients and maintains water uptake as soil water retreats, enhancing the chances of survival in the first dry season. We outline an interpretative scenario for the special role of large seeds (>15 mg) in nutrient- and water-limited environments that recognizes the critical role of N and P for photosynthesis in ensuring sufficient C-supply to the rapidly descending roots for effective drought-avoidance by the young plant.展开更多
Natural forest recovery on abandoned farmland is hindered by a variety of factors and active restoration plays an important role when quick afforestation is desired. We investigated seedling survival of four transplan...Natural forest recovery on abandoned farmland is hindered by a variety of factors and active restoration plays an important role when quick afforestation is desired. We investigated seedling survival of four transplanted native tree species (Quercus myrsinifolia, Quercus serrata, Aphananthe aspera, and Rhus sylvestris) by experimentally manipulating the vegetation cover, which was mainly dominated by dwarf bamboo (Pleioblastus chino), and herbivore access to the planting sites on farmland that had been abandoned for 15 years at the start of the study. Few transplanted seedlings of any species survived under intact vegetation cover, irrespective of herbivore presence. In gaps in the vegetation cover, winter browsing by Japanese hare (Lepus brachyurus) damaged all species. However, lower browsing frequency and higher resprouting ability after grazing of the seedlings enabled both Quercus species to survive better than the other species. These results indicate that dwarf bamboo and the hare jointly limit the establishment of native trees in old fields. If active afforestation by transplanting seedlings at sites dominated by dwarf bamboo is planned, a combination of vegetation removal, selection of suitable species, and temporary seedling protection will be most effective.展开更多
Seed size and the growth environment are important variables that influence seed germination, growth and biomass of seedlings and future tree harvest and should thus be taken into account in agroforestry and reforesta...Seed size and the growth environment are important variables that influence seed germination, growth and biomass of seedlings and future tree harvest and should thus be taken into account in agroforestry and reforestation programmes for endangered species like Pterocarpus erinaceus. In the present study, to assess seedling germination and vigour in P. erinaceus as a function of seed size in two environments, 1080 seeds and 360 seedlings were evaluated at two separate sites in Côte d'Ivoire. The results show that large seeds had very high germination rates (up to 100%) and produced more vigorous plants better able to adapt to climate change. The maternal environment and seed size had a significant influence on seed germination (P < 0.05) and seedling development (P < 0.05) and biomass (P < 0.05). Seedlings were most successful at the site with a humid tropical climate (Daloa). Seedling leaves had the same resistance regardless of seed size and study site, but leaf moisture content was more stable in seedlings grown from medium and small seeds. These results will help guide conservation strategies for the species and are key factors for rural populations, loggers, and forest management structures for the silviculture of this species.展开更多
Strong seedlings are essential for high yield.To explore the foundation of strong seedlings,we investigated various factors influencing the conversion and distribution of seed storage reserves during seedling establis...Strong seedlings are essential for high yield.To explore the foundation of strong seedlings,we investigated various factors influencing the conversion and distribution of seed storage reserves during seedling establishment in maize inbred lines.Three maize inbred lines were used to explore the effects of seed size,seed vigor,illumination duration,temperature,water content,and salt concentration of the seedling medium on the utilization of seed storage reserves during seedling establishment.The results showed that the conversion rate of small seeds was 3.69 to 17.71%higher than that of large seeds.Moreover,prolonged illumination time was conducive to the formation of strong seedlings.However,low temperature,drought stress and salt stress reduced the conversion rate of seed storage reserves and increased the root/shoot ratio.These results could be used to guide field management during seedling emergence and develop improved germplasm with a high conversion rate of seed storage reserves.展开更多
Rice(Oryza sativa)plants acquired excess photosynthates in the form of nonstructural carbohydrates(NSCs)in their stems and grain.Despite keen interest in rice NSC,the dynamics of NSC accumulation,translocation and re-...Rice(Oryza sativa)plants acquired excess photosynthates in the form of nonstructural carbohydrates(NSCs)in their stems and grain.Despite keen interest in rice NSC,the dynamics of NSC accumulation,translocation and re-accumulation have not yet been well investigated.AG1 and AG2 QTLs associated with flooding tolerance through catalyzing starch into soluble sugar in germinating seeds.Here we conducted three experiments,greenhouse and field to lay the groundwork for large-scale diversity studies on grain NSC and some agronomic traits under direct-seeded rice(DSR)system,using elite lines incorporating AG1,AG2 and AG1-AG2 QTLs into the popular varieties PSB Rc82 and Ciherang-Sub1 along with the donors Kho Hlan On(AG1)and Ma-Zhan Red(AG2).In germinating seedlings,soluble sugars increased,while starch concentration decreased gradually especially in the tolerant checks and AG1-AG2 introgression lines under flooded soil.Soluble sugar accumulation in stem started to increase from the vegetative stage and peaked at the panicle initiation stage then gradually decreased towards the maturity stage.But Sub1-AG lines had higher sugar and starch concentrations at different growth stages than other genotypes in wet season 2016 and dry season 2017.Plant survival rate was positively correlated with the stem NSC at the early vegetative stage(21 days after sowing),and stem NSC was positively associated with plant height at different growth stages.Among the tested seeding rate,the most suitable seeding rate,4 g/m2 with shallow burial depth(0.5 cm),resulted in better seedling establishment,relatively higher seedling vigor index and higher leaf area index under flooding in DSR system.Introgression of AG1-AG2 QTLs had no any negative impact on nonstructural carbohydrate,germination rate,and growth and biomass production.展开更多
The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate dur...The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate during seedling production while reducing the number of seedling trays.This study conducted field experiments from 2021 to 2022,using transplanting seedling ages of 10 and 15 days to explore the effects of 250,300,and 350 g/tray on the seedling quality,mechanical transplantation quality,yields,and economic benefits of rice.The commonly used combination of 150 g/tray with a 20-day seedling age in rice production was used as CK.The cultivation of seedlings under a high seeding rate and short seedling age significantly affected seedling characteristics,but there was no significant difference in seedling vitality compared to CK.The minimum number of rice trays used in the experiment was observed in the treatment of 350-10(300 g/tray and 10-day seedling age),only 152-155 trays ha^(-1),resulting in a 62%reduction in the number of trays needed.By increasing the seeding rate of rice,missed holes during mechanical transplantation decreased by 2.8 to 4%.The treatment of 300-15(300 g/tray and 15-day seedling age)achieved the highest yields and economic gains.These results indicated that using crop straw boards can reduce the application of seedling trays.On that basis,rice yields can be increased by raising the seeding rate and shortening the seedling age of rice without compromising seedling quality.展开更多
[Objectives]To screen effective agents for the management of root rot in tobacco floating seedlings.[Methods]A total of eight treatments were implemented in a large-scale field trial,which included three replications....[Objectives]To screen effective agents for the management of root rot in tobacco floating seedlings.[Methods]A total of eight treatments were implemented in a large-scale field trial,which included three replications.Each treatment was administered at the recommended dosages.[Results]The application of Metalaxyl-M·Fludioxonil+amino acids demonstrated a control efficacy of 93.65%against root rot in tobacco floating seedlings.In comparison,the application of Metalaxyl-M·Fludioxonil alone exhibited a control efficacy of 88.42%.The most effective treatment for promoting root growth in tobacco seedlings was Metalaxyl-M·Fludioxonil+amino acids,which resulted in a 54.65%increase in root growth compared to the blank control.This was followed by the application of Metalaxyl-M·Fludioxonil alone,which yielded a 39.53%increase in root growth relative to the blank control.[Conclusions]The application of Metalaxyl-M·Fludioxonil+amino acids is recommended for use in the seedling pools of tobacco seedling cultivation.Specifically,it is advised to incorporate 1 mL of Metalaxyl-M·Fludioxonil and 2 mL of amino acids into each seedling tray prior to their introduction into the seedling pool.This treatment has demonstrated significant efficacy in preventing and controlling root rot in tobacco floating seedlings,while also promoting the health of the root system and ensuring the quality of transplanted tobacco seedlings.展开更多
Planting genetically improved,fast-growing tree seedlings is gaining importance as a strategy to enhance forest productivity and reduce labor requirements during plantation establishment.In this study,we evaluated the...Planting genetically improved,fast-growing tree seedlings is gaining importance as a strategy to enhance forest productivity and reduce labor requirements during plantation establishment.In this study,we evaluated the early growth and survival of advanced-generation Cryptomeria japonica seedlings compared to conventional stock,under varying planting densities and cultivation methods.A field experiment was conducted over 5 years using containergrown and bare-root seedlings derived from first-and second-generation plus trees,alongside traditional seedlings.The results showed that advanced-generation seedlings exhibited higher growth in tree height,stem diameter,and crown development than traditional seedlings,particularly when planted as container stock.These seedlings also had higher survival rates,likely due to their rapid initial height growth,which reduced the risks of accidental damage during weeding operations.Wider planting intervals increased the risk of man-made injury and seedling mortality,while faster-growing seedlings were more likely to escape from competing vegetation.Our findings highlight the potential of improved seedling stock to enhance early plantation success and reduce management inputs in the critical establishment phase of forestry.展开更多
Excessive accumulation of cadmium (Cd) impairs crop growth by inducing oxidative damage through the generation of reactive oxygen species (ROS). In this study, a biocompatible ferruginated carbon quantum dots (Fe-CQDs...Excessive accumulation of cadmium (Cd) impairs crop growth by inducing oxidative damage through the generation of reactive oxygen species (ROS). In this study, a biocompatible ferruginated carbon quantum dots (Fe-CQDs) nanozyme is developed to target ROS, thereby reducing oxidative damage and improving the absorption and transfer of Cd ions in wheat. Notably, Fe-CQDs exhibit multi-enzyme activities mimicking peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD), enabling effective neutralization of active species such as hydroxyl radicals (•OH), hydrogen peroxide (H_(2)O_(2)), and superoxide anions (O_(2)•^(-)). Importantly, root application of 10 mg L^(-1) Fe-CQDs alleviates Cd stress and promotes wheat growth in both hydroponic and soil cultures. Specifically, the levels of O_(2)•^(-), H_(2)O_(2), and malondialdehyde (MDA) in leaf tissues decrease, whereas the non-enzyme antioxidant, reduced glutathione (GSH), increases. Cell wall thickness in the Fe-CQDs-treated group is reduced by 42.4% compared with the Cd group. Moreover, Fe-CQDs enhance the expression of genes related to antioxidants, stress resistance, Cd detoxification, and nutrient transport. Transcriptomic and metabolomic analyses show that Fe-CQDs stimulate the production of flavonoids and regulate the activity of metal transporter genes (YSL, ABC, ZIP) to maintain ROS homeostasis. These findings highlight the potential of Fe-CQDs nanozyme platforms in mitigating oxidative damage and enhancing crop growth, offering new insights into the application of nanobiotechnology in agriculture.展开更多
The oilseed crop Camelina sativa exhibits salinity tolerance,but the effects on early growth stages across a range of different salts and in combination with salicylic acid(SA)have not been thoroughly evaluated.In thi...The oilseed crop Camelina sativa exhibits salinity tolerance,but the effects on early growth stages across a range of different salts and in combination with salicylic acid(SA)have not been thoroughly evaluated.In this study,seeds were germinated in varying concentrations of six salts(NaCl,CaCl_(2),ZnCl_(2),KCl,MgSO_(4),and Na2SO_(4))with or without 0.5 mM SA.Using the halotime model,we estimated salt thresholds for germination and parameters of seedling growth.Germination and seedling growth parameters of camelina significantly decreased with increasing salt concentration across all salt types.Salts containing Zn and SO_(4) were most detrimental to germination and seedling growth.Except for KCl,0.5 mM SA generally reduced the salinity tolerance threshold(Saltb(50))of camelina.Specifically,Saltb(50)was 21.5%higher for KCl and 16.1%,25.0%,54.9%,21.0%,and 5.6%lower for CaCl_(2),NaCl,MgSO_(4),Na2SO_(4),and ZnCl_(2),respectively,when 0.5 mM SA was compared to 0 mM SA.Furthermore,camelina seedling growth was consistently more sensitive than germination across all salt types.SA did not significantly enhance germination or seedling growth and was harmful when combined with certain salts or at the germination stage.It can be concluded that both the type of salt and the concentration of SA are as critical as the salt concentration in saline irrigation water.展开更多
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(2019QZKK0502 to H.S.)the Yunnan Applied Basic Research Project(202001AT070060 to J.G.C.)+1 种基金the CAS“Light ofWest China”Program(J.G.C.)the Young Academic and Technical Leader Raising Foundation of Yunnan Province(202205AC160053 to J.G.C.).
文摘Population shrinkage of alpine cushion plants with ongoing climate warming has been empirically confirmed.Since cushion plants play important roles in sustaining alpine plant community and ecosystem functions,their population dynamics may directly influence the future alpine ecosystems.However,little is known about how climate warming affect cushion population recruitment,especially at early life-history stages.In this study,we conducted a laboratory simulation of climate warming to detect the effects of warming temperature and associated moisture and light changes on seed germination and seedling growth of the typical alpine cushion plant Arenaria oreophila.Results suggested that increasing temperature indeed exerted strong constraints on the population recruitment processes.Specifically,increased temperatures could quickly initialize seed germination(4e6 days at higher temperatures vs.29 e32 days at low temperature,respectively,after sowing),accelerate them to reach the maximum germination percentage(9e19 days at higher temperatures vs.57e86 days at low temperature,respectively,after sowing)and significantly accelerate seedling growth rate.However,higher temperatures accelerated seedling mortality(more than 80%).In addition,lower light availability also increased seedling mortality though it could generally increase the final seed germination percentage.The effects of water might be dependent on temperature and light.All results suggested that cushion A.oreophila is quite sensitive to climate warming which strongly constrains its seedling establishment process.We,therefore,speculate that the continuing climate warming in future will exert uncertain risks in the persistence of cushion A.oreophila,possibly by constraining the process of seedling recruitments.
基金supported by the Key Project of Science and Technology Research by Chongqing Education Commission under Grant KJZD-K202400610the Chongqing Natural Science Foundation General Project Grant CSTB2025NSCQ-GPX1263.
文摘The ubiquitous adoption of mobile devices as essential platforms for sensitive data transmission has heightened the demand for secure client-server communication.Although various authentication and key agreement protocols have been developed,current approaches are constrained by homogeneous cryptosystem frameworks,namely public key infrastructure(PKI),identity-based cryptography(IBC),or certificateless cryptography(CLC),each presenting limitations in client-server architectures.Specifically,PKI incurs certificate management overhead,IBC introduces key escrow risks,and CLC encounters cross-system interoperability challenges.To overcome these shortcomings,this study introduces a heterogeneous signcryption-based authentication and key agreement protocol that synergistically integrates IBC for client operations(eliminating PKI’s certificate dependency)with CLC for server implementation(mitigating IBC’s key escrow issue while preserving efficiency).Rigorous security analysis under the mBR(modified Bellare-Rogaway)model confirms the protocol’s resistance to adaptive chosen-ciphertext attacks.Quantitative comparisons demonstrate that the proposed protocol achieves 10.08%–71.34%lower communication overhead than existing schemes across multiple security levels(80-,112-,and 128-bit)compared to existing protocols.
基金funded by the National Key Research and Development Program of China(Grant No.2019YFD1001900)the HZAU-AGIS Cooperation Fund(Grant No.SZYJY2022006).
文摘Nondestructive measurement technology of phenotype can provide substantial phenotypic data support for applications such as seedling breeding,management,and quality testing.The current method of measuring seedling phenotypes mainly relies on manual measurement which is inefficient,subjective and destroys samples.Therefore,the paper proposes a nondestructive measurement method for the canopy phenotype of the watermelon plug seedlings based on deep learning.The Azure Kinect was used to shoot canopy color images,depth images,and RGB-D images of the watermelon plug seedlings.The Mask-RCNN network was used to classify,segment,and count the canopy leaves of the watermelon plug seedlings.To reduce the error of leaf area measurement caused by mutual occlusion of leaves,the leaves were repaired by CycleGAN,and the depth images were restored by image processing.Then,the Delaunay triangulation was adopted to measure the leaf area in the leaf point cloud.The YOLOX target detection network was used to identify the growing point position of each seedling on the plug tray.Then the depth differences between the growing point and the upper surface of the plug tray were calculated to obtain plant height.The experiment results show that the nondestructive measurement algorithm proposed in this paper achieves good measurement performance for the watermelon plug seedlings from the 1 true-leaf to 3 true-leaf stages.The average relative error of measurement is 2.33%for the number of true leaves,4.59%for the number of cotyledons,8.37%for the leaf area,and 3.27%for the plant height.The experiment results demonstrate that the proposed algorithm in this paper provides an effective solution for the nondestructive measurement of the canopy phenotype of the plug seedlings.
基金funded by Bangladesh Agricultural University Research System(BAURES)through the Project No.2024/48/BAU.
文摘Seaweed extract contains plant growth regulators and bio-stimulants that enhance plant growth and development.In Bangladesh,winter rice(Boro rice)in the nursery bed often shows poor seed emergence and weak seedling growth due to low temperature.This problem can be addressed by using seaweed extract as a seed priming agent and bio-stimulant.The objective of this study was to evaluate the effectiveness of seaweed extract(Crop Plus)on seed emergence,seedling growth,and vigor of winter rice in the nursery.Two experiments were conducted at Bangladesh Agricultural University using BRRI dhan89.The laboratory experiment consisted of 17 treatments combining three concentrations of Crop Plus(5000,10,000 and 15,000 ppm)and four priming durations(6,12,18,and 24 h),along with hydro-priming and a no priming as control.Seed priming with 15,000 ppm for 24 h produced the highest germination percentage and superior seedling growth traits.The nursery bed experiment comprised 11 treatments combining two doses(1 mL m^(−2)and 2 mL m^(−2))of Crop Plus and five different foliar application schedules,along with a control.All treatments outperformed the control,with the best results from Crop Plus@2 mL m^(−2)applied at 20 and 30 days after sowing(DAS).Overall,the treatment involving seed priming with 15,000 ppm seaweed extract for 24 h,followed by nursery application at 2 mL m^(−2)at 20 and 30 DAS,resulted in higher germination and improved early growth of winter rice.However,further validation across multiple locations,seasons,and rice cultivars is recommended.
基金supported by an International Cooperation Key Plan of Shaanxi Province(Grant No.2022KWZ-12)an Agricultural Science Innovation and Transformation Project of Shaanxi Province[Grant No.NYKJ-2022-YL(XN)12]a High-End Foreign Expert Recruitment Program(Grant No.G2022172006L).
文摘Wind disturbance has emerged as a potential eco-friendly method for seedling cultivation.In this study,an electromechanical device was designed and built to investigate the effects of airflow on the micro-environment and physiological activities of tomato seedlings in seedbeds by controlled experiments.The results indicated that airflow could enhance CO_(2) concentration near the seedling canopy,accelerate water evaporation from the seedling substrate,and reduce fluctuations in the temperature and humidity in microclimate.The photosynthetic rates of leaves at the 4th,7th,and 10th positions in seedlings subjected to airflow increased by 25.04%,8.23%,and 8.47%,respectively,whereas the transpiration rates increased by 15.59%,22.28%,and 13.26%,respectively when compared to the control group.Additionally,the strong seedling index of seedlings treated with airflow and exogenous iron element increased by 26.02%and 31.5%,respectively.Compared to seedlings treated with exogenous iron element,the geometric mean diameter of the pith tissue cells in the stems of seedlings subjected to airflow disturbance was reduced by approximately 18.66%,while the elastic modulus and bending strength of the stems increased by 10.01%and 5.89%,respectively.Similarly,the volume of root tissue cells decreased by 19.22%,but the elastic modulus of the roots increased by 6.46%.This study confirms that airflow significantly enhances seedling resilience to abiotic stress,yielding similar or better outcomes than exogenous iron application.It provides both theoretical and practical support for using airflow disturbance as a green technology for cultivating robust seedlings.
文摘When making assessments of forest resources,there is nearly ubiquitous interest in quantifying current status and trends in tree biomass and carbon stocks.While important at various spatial scales,typical estimations pertinent to broad forest management and policy issues are conducted for large areas such as state,regional,and national perspectives.These assessments are usually accomplished using large-area forest inventory data collected by National Forest Inventory(NFI)programs.While NFI efforts commonly collect size data for individual trees,there is often limited information for tree seedlings,e.g.,frequency by species.To fully describe the tree population across the entire range of sizes present,this study proposes methods to predict individual seedling groundline diameter and height using models developed from trees having a diameter at breast height(DBH)less than 7.62 cm.These attributes are subsequently used for the prediction of seedling stem volume,total aboveground biomass,and carbon content.The results suggest a smooth transition in tree attributes as size increases to where direct measurement of individual trees and prediction of their volume,biomass,and carbon are implemented as part of standard inventory protocols.Analyses including the full spectrum of tree sizes show that seedlings contribute roughly 0.6%–0.7%of the total tree volume/mass.This additional suite of information provides opportunities for more holistic assessments across the full spectrum of the tree resource or for specialized subdomains that include the seedling component.
基金This work was supported by the National Basic Research Program of China (Grant No. 2002CCA04100);the Key Science and Technology Program of Zhejiang Province, China (Grant No. 2003C34012);China Rice Science Foundation (Grant No. CRSF0003338);International Atomic Energy Agency (IAEA) Training Program.
文摘Elongations of coleoptile and mesocotyl are related directly to rice seedling establishment in soil and height of plant is related to lodging in rice production. Twelve typical rice cultivars with different lengths of coleoptile and mesocotyl (long, medium and short) were selected by screening the lengths of coleoptile and mesocotyl in 1500 accessions. The seedling establishments of these typical cultivars were compared under the combinations of different sowing depths and flooding durations, and two semi-dwarf varieties (G140, Zhong 96-21) with good seedling establishments and optimum mesocotyl lengths were found. The length of mesocotyl was completely fitted negative binomial distribution and the length of coleoptile was nearly fitted Iognormal distribution. Analysis of the relationships among mesocotyl, coleoptile, seeding depth, flooding duration, and their interactions to seedling establishment percentage showed that there existed significant relations among mesocotyl, coleoptile, mesocotyl x coleoptile, seeding depth, flooding duration and mesocotyl x sowing depth in the experiment for seedling establishment.
文摘Manglietia patungensis is an endangered species distributed aggregately in evergreen broad-leaved forest communities in Southwest China. A controlling experiment was employed to test the effects of soil type and shade degree on seed germination and seedling establishment by using four soil types and three shade treatments with five replicates. Results showed that the germination rate of M. patungensis seeds was relatively low ranging from 19% to 31%. Shade degree and soil type had no significant effect on seed germination rate, but influenced germination dynamics. Both shade degree and soil type treatments significantly affected seedling survival and seedling growth. Seedling survival rate increased with increasing light density. Increased light also promoted biomass accumulation and root development of seedlings. The biomass of the seedlings under full light condition increased 72% comparing with the seedlings under 80% shade degree. Root depth, root area and cross number increased with the increase of light density. Seedlings on farmland soil survived better than that on other three kinds of soil. The seedling survival rate in the farmland soil reached 91.4%, but was reduced to 80.3%, 78.0% and 52.8% in old-field soil, sandy soil and forest soil respectively. Total biomass, aboveground biomass and root biomass of seedlings in forest soil was the highest, followed by seedlings in sandy and old-field soils respectively, and seedlings in farmland soil ranked the least. Some suggestions were finally put forward for the conservation of M. patungensis based on the research results.
文摘Seeds are a source of organic (carbon, C) and mineral (nitrogen, N and phosphorus, P) nutrients for the growing seedling. There is much information on seed mass and N and P contents, and the relationship between these and seedling mass. Within the world’s temperate regions, these collectively show that N and P concentrations remain constant or rise with increase in seed mass and that seeds are larger and more nutrient-enriched in poorer soils. Seed N and P were more important than seed C in accounting for seedling mass in 85% of studies we assessed. In nutrient- and water-limited environments that are not light-limited, large seeds routinely provision the seedling with N and P that enhance C-fixation and thus general growth in the first wet season. This system is so efficient that growth response to soil nutrients may be negligible in first-year seedlings arising from seeds > 15 mg mass, N content > 5 mg and P content > 1.6 mg. The elongating taproot system absorbs nutrients and maintains water uptake as soil water retreats, enhancing the chances of survival in the first dry season. We outline an interpretative scenario for the special role of large seeds (>15 mg) in nutrient- and water-limited environments that recognizes the critical role of N and P for photosynthesis in ensuring sufficient C-supply to the rapidly descending roots for effective drought-avoidance by the young plant.
文摘Natural forest recovery on abandoned farmland is hindered by a variety of factors and active restoration plays an important role when quick afforestation is desired. We investigated seedling survival of four transplanted native tree species (Quercus myrsinifolia, Quercus serrata, Aphananthe aspera, and Rhus sylvestris) by experimentally manipulating the vegetation cover, which was mainly dominated by dwarf bamboo (Pleioblastus chino), and herbivore access to the planting sites on farmland that had been abandoned for 15 years at the start of the study. Few transplanted seedlings of any species survived under intact vegetation cover, irrespective of herbivore presence. In gaps in the vegetation cover, winter browsing by Japanese hare (Lepus brachyurus) damaged all species. However, lower browsing frequency and higher resprouting ability after grazing of the seedlings enabled both Quercus species to survive better than the other species. These results indicate that dwarf bamboo and the hare jointly limit the establishment of native trees in old fields. If active afforestation by transplanting seedlings at sites dominated by dwarf bamboo is planned, a combination of vegetation removal, selection of suitable species, and temporary seedling protection will be most effective.
基金financed by the Ministry of Higher Education and Scientific Research of Côte d’Ivoirethe French Development Agency and IRD (Institut de Recherche pour le Developpement) in the framework of PRESeD-CI 2 (Renewed Partnership for Research for Development in Côte d’Ivoire)C2D (Debt Reduction Contract) of the AMRUGECI project (Support for the Modernization and Reform of Universities and Grandes Ecoles of Côte d’Ivoire)
文摘Seed size and the growth environment are important variables that influence seed germination, growth and biomass of seedlings and future tree harvest and should thus be taken into account in agroforestry and reforestation programmes for endangered species like Pterocarpus erinaceus. In the present study, to assess seedling germination and vigour in P. erinaceus as a function of seed size in two environments, 1080 seeds and 360 seedlings were evaluated at two separate sites in Côte d'Ivoire. The results show that large seeds had very high germination rates (up to 100%) and produced more vigorous plants better able to adapt to climate change. The maternal environment and seed size had a significant influence on seed germination (P < 0.05) and seedling development (P < 0.05) and biomass (P < 0.05). Seedlings were most successful at the site with a humid tropical climate (Daloa). Seedling leaves had the same resistance regardless of seed size and study site, but leaf moisture content was more stable in seedlings grown from medium and small seeds. These results will help guide conservation strategies for the species and are key factors for rural populations, loggers, and forest management structures for the silviculture of this species.
基金supported by the National Key Research and Development Program of China(2018YFD0100900)the Special Fund of Agricultural Significant Application Technique Innovation of Shandong Province,China(SDAIT-02-02)the Maize Improved Seed Project in Shandong Province,China(2019LZGC002-1)。
文摘Strong seedlings are essential for high yield.To explore the foundation of strong seedlings,we investigated various factors influencing the conversion and distribution of seed storage reserves during seedling establishment in maize inbred lines.Three maize inbred lines were used to explore the effects of seed size,seed vigor,illumination duration,temperature,water content,and salt concentration of the seedling medium on the utilization of seed storage reserves during seedling establishment.The results showed that the conversion rate of small seeds was 3.69 to 17.71%higher than that of large seeds.Moreover,prolonged illumination time was conducive to the formation of strong seedlings.However,low temperature,drought stress and salt stress reduced the conversion rate of seed storage reserves and increased the root/shoot ratio.These results could be used to guide field management during seedling emergence and develop improved germplasm with a high conversion rate of seed storage reserves.
基金This study was supported by the Lee Foundation Scholarship(PhD)through International Rice Research Institute,the PhilippinesThe authors are thankful to Melencio J.APOSTOL for his technical assistance,and to Frederickson ENTILA and Evangelina S.ELLA for helpful suggestions and comments during this study.
文摘Rice(Oryza sativa)plants acquired excess photosynthates in the form of nonstructural carbohydrates(NSCs)in their stems and grain.Despite keen interest in rice NSC,the dynamics of NSC accumulation,translocation and re-accumulation have not yet been well investigated.AG1 and AG2 QTLs associated with flooding tolerance through catalyzing starch into soluble sugar in germinating seeds.Here we conducted three experiments,greenhouse and field to lay the groundwork for large-scale diversity studies on grain NSC and some agronomic traits under direct-seeded rice(DSR)system,using elite lines incorporating AG1,AG2 and AG1-AG2 QTLs into the popular varieties PSB Rc82 and Ciherang-Sub1 along with the donors Kho Hlan On(AG1)and Ma-Zhan Red(AG2).In germinating seedlings,soluble sugars increased,while starch concentration decreased gradually especially in the tolerant checks and AG1-AG2 introgression lines under flooded soil.Soluble sugar accumulation in stem started to increase from the vegetative stage and peaked at the panicle initiation stage then gradually decreased towards the maturity stage.But Sub1-AG lines had higher sugar and starch concentrations at different growth stages than other genotypes in wet season 2016 and dry season 2017.Plant survival rate was positively correlated with the stem NSC at the early vegetative stage(21 days after sowing),and stem NSC was positively associated with plant height at different growth stages.Among the tested seeding rate,the most suitable seeding rate,4 g/m2 with shallow burial depth(0.5 cm),resulted in better seedling establishment,relatively higher seedling vigor index and higher leaf area index under flooding in DSR system.Introgression of AG1-AG2 QTLs had no any negative impact on nonstructural carbohydrate,germination rate,and growth and biomass production.
基金funded by the Jiangsu Key Research Program,China(BE2022338)the Jiangsu Agricultural Science and Technology Innovation Fund,China(CX(23)3107)+3 种基金the Natural Science Foundation of the Jiangsu Higher Education Institutions,China(22KJB210004)the Jiangsu Province Agricultural Major Technology Collaborative Promotion Project,China(2022-ZYXT-04-1)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(KYCX23_3569)the Priority Academic Program Development of Jiangsu Higher Education Institutions,China.
文摘The high labor demand during rice seedling cultivation and transplantation poses a significant challenge in advancing machine-transplanted rice cultivation.This problem may be solved by increasing the seeding rate during seedling production while reducing the number of seedling trays.This study conducted field experiments from 2021 to 2022,using transplanting seedling ages of 10 and 15 days to explore the effects of 250,300,and 350 g/tray on the seedling quality,mechanical transplantation quality,yields,and economic benefits of rice.The commonly used combination of 150 g/tray with a 20-day seedling age in rice production was used as CK.The cultivation of seedlings under a high seeding rate and short seedling age significantly affected seedling characteristics,but there was no significant difference in seedling vitality compared to CK.The minimum number of rice trays used in the experiment was observed in the treatment of 350-10(300 g/tray and 10-day seedling age),only 152-155 trays ha^(-1),resulting in a 62%reduction in the number of trays needed.By increasing the seeding rate of rice,missed holes during mechanical transplantation decreased by 2.8 to 4%.The treatment of 300-15(300 g/tray and 15-day seedling age)achieved the highest yields and economic gains.These results indicated that using crop straw boards can reduce the application of seedling trays.On that basis,rice yields can be increased by raising the seeding rate and shortening the seedling age of rice without compromising seedling quality.
文摘[Objectives]To screen effective agents for the management of root rot in tobacco floating seedlings.[Methods]A total of eight treatments were implemented in a large-scale field trial,which included three replications.Each treatment was administered at the recommended dosages.[Results]The application of Metalaxyl-M·Fludioxonil+amino acids demonstrated a control efficacy of 93.65%against root rot in tobacco floating seedlings.In comparison,the application of Metalaxyl-M·Fludioxonil alone exhibited a control efficacy of 88.42%.The most effective treatment for promoting root growth in tobacco seedlings was Metalaxyl-M·Fludioxonil+amino acids,which resulted in a 54.65%increase in root growth compared to the blank control.This was followed by the application of Metalaxyl-M·Fludioxonil alone,which yielded a 39.53%increase in root growth relative to the blank control.[Conclusions]The application of Metalaxyl-M·Fludioxonil+amino acids is recommended for use in the seedling pools of tobacco seedling cultivation.Specifically,it is advised to incorporate 1 mL of Metalaxyl-M·Fludioxonil and 2 mL of amino acids into each seedling tray prior to their introduction into the seedling pool.This treatment has demonstrated significant efficacy in preventing and controlling root rot in tobacco floating seedlings,while also promoting the health of the root system and ensuring the quality of transplanted tobacco seedlings.
基金supported by FFPRI FTBC Operational Expense Grants。
文摘Planting genetically improved,fast-growing tree seedlings is gaining importance as a strategy to enhance forest productivity and reduce labor requirements during plantation establishment.In this study,we evaluated the early growth and survival of advanced-generation Cryptomeria japonica seedlings compared to conventional stock,under varying planting densities and cultivation methods.A field experiment was conducted over 5 years using containergrown and bare-root seedlings derived from first-and second-generation plus trees,alongside traditional seedlings.The results showed that advanced-generation seedlings exhibited higher growth in tree height,stem diameter,and crown development than traditional seedlings,particularly when planted as container stock.These seedlings also had higher survival rates,likely due to their rapid initial height growth,which reduced the risks of accidental damage during weeding operations.Wider planting intervals increased the risk of man-made injury and seedling mortality,while faster-growing seedlings were more likely to escape from competing vegetation.Our findings highlight the potential of improved seedling stock to enhance early plantation success and reduce management inputs in the critical establishment phase of forestry.
基金supported by the National Natural Science Foundation of China (3237152 and 22104102)Natural Science Foundation of Sichuan Province (2025ZNSFSC0155)+1 种基金Open Project Program (SKL-KF202416) of State Key Laboratory of Crop Gene Exploration and Utilization in Southwest ChinaTwo-Way Support Programs of Sichuan Agricultural University (P202105)
文摘Excessive accumulation of cadmium (Cd) impairs crop growth by inducing oxidative damage through the generation of reactive oxygen species (ROS). In this study, a biocompatible ferruginated carbon quantum dots (Fe-CQDs) nanozyme is developed to target ROS, thereby reducing oxidative damage and improving the absorption and transfer of Cd ions in wheat. Notably, Fe-CQDs exhibit multi-enzyme activities mimicking peroxidase (POD), catalase (CAT), and superoxide dismutase (SOD), enabling effective neutralization of active species such as hydroxyl radicals (•OH), hydrogen peroxide (H_(2)O_(2)), and superoxide anions (O_(2)•^(-)). Importantly, root application of 10 mg L^(-1) Fe-CQDs alleviates Cd stress and promotes wheat growth in both hydroponic and soil cultures. Specifically, the levels of O_(2)•^(-), H_(2)O_(2), and malondialdehyde (MDA) in leaf tissues decrease, whereas the non-enzyme antioxidant, reduced glutathione (GSH), increases. Cell wall thickness in the Fe-CQDs-treated group is reduced by 42.4% compared with the Cd group. Moreover, Fe-CQDs enhance the expression of genes related to antioxidants, stress resistance, Cd detoxification, and nutrient transport. Transcriptomic and metabolomic analyses show that Fe-CQDs stimulate the production of flavonoids and regulate the activity of metal transporter genes (YSL, ABC, ZIP) to maintain ROS homeostasis. These findings highlight the potential of Fe-CQDs nanozyme platforms in mitigating oxidative damage and enhancing crop growth, offering new insights into the application of nanobiotechnology in agriculture.
基金the Genetics and Agricultural Biotechnology Institute of Tabarestan (GABIT) Sari Agricultural Sciences and Natural Resources University (SANRU) for the use of the services and financial supports of this research
文摘The oilseed crop Camelina sativa exhibits salinity tolerance,but the effects on early growth stages across a range of different salts and in combination with salicylic acid(SA)have not been thoroughly evaluated.In this study,seeds were germinated in varying concentrations of six salts(NaCl,CaCl_(2),ZnCl_(2),KCl,MgSO_(4),and Na2SO_(4))with or without 0.5 mM SA.Using the halotime model,we estimated salt thresholds for germination and parameters of seedling growth.Germination and seedling growth parameters of camelina significantly decreased with increasing salt concentration across all salt types.Salts containing Zn and SO_(4) were most detrimental to germination and seedling growth.Except for KCl,0.5 mM SA generally reduced the salinity tolerance threshold(Saltb(50))of camelina.Specifically,Saltb(50)was 21.5%higher for KCl and 16.1%,25.0%,54.9%,21.0%,and 5.6%lower for CaCl_(2),NaCl,MgSO_(4),Na2SO_(4),and ZnCl_(2),respectively,when 0.5 mM SA was compared to 0 mM SA.Furthermore,camelina seedling growth was consistently more sensitive than germination across all salt types.SA did not significantly enhance germination or seedling growth and was harmful when combined with certain salts or at the germination stage.It can be concluded that both the type of salt and the concentration of SA are as critical as the salt concentration in saline irrigation water.