Background:Using native wildflowers for restoring marginal lands has gained considerable popularity.Establishment of wildflowers can be challenging due to several environmental factors.Restoring the microbial communit...Background:Using native wildflowers for restoring marginal lands has gained considerable popularity.Establishment of wildflowers can be challenging due to several environmental factors.Restoring the microbial community in degraded habitats can potentially result in the native plant performance and habitat restoration.This study was conducted to investigate the impact of native soil microbes and seeding depth on germination of south Texas native wildflowers.Two wildflower species,Ratibida columnifera(Nutt.)(Mexican Hat)and Verbesina encelioides(Cav.)(cowpen daisy),were treated with microbial wash extracted from native soils,and germination rate was recorded for 14-day period.We further analyzed the growth,biomass allocation,and root colonization by mycorrhizal fungi in these two plants growing them in a plant growth chamber for 6 weeks.To determine the impact of seeding depth,we planted the seeds of the two plant species at 2-cm,6-cm,and 12-cm depth and monitored germination and plant growth.Results:The two species responded differently to the seeding depth and microbial wash treatments.Microbial wash treatment resulted in higher germination rate in R.columnifera compared to control,while it did not have any impact on V.encelioides seed germination.While microbial treatment did not influence the total biomass,it had a significant impact on the biomass allocation in both the plant species.R.columnifera seeds germinated at both 2-cm and 6-cm depth and did not germinate at 12 cm,while the V.encelioides seeds germinated only at 2 cm and did not germinate at 6-cm or 12-cm seeding depth.Conclusions:While our results are species specific,our results indicate that native soil microbes can potentially improve the seed germination and growth of wildflowers.Our results also indicate the importance of specific seeding depth when sowing wildflower seeds for habitat restoration.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
文摘Background:Using native wildflowers for restoring marginal lands has gained considerable popularity.Establishment of wildflowers can be challenging due to several environmental factors.Restoring the microbial community in degraded habitats can potentially result in the native plant performance and habitat restoration.This study was conducted to investigate the impact of native soil microbes and seeding depth on germination of south Texas native wildflowers.Two wildflower species,Ratibida columnifera(Nutt.)(Mexican Hat)and Verbesina encelioides(Cav.)(cowpen daisy),were treated with microbial wash extracted from native soils,and germination rate was recorded for 14-day period.We further analyzed the growth,biomass allocation,and root colonization by mycorrhizal fungi in these two plants growing them in a plant growth chamber for 6 weeks.To determine the impact of seeding depth,we planted the seeds of the two plant species at 2-cm,6-cm,and 12-cm depth and monitored germination and plant growth.Results:The two species responded differently to the seeding depth and microbial wash treatments.Microbial wash treatment resulted in higher germination rate in R.columnifera compared to control,while it did not have any impact on V.encelioides seed germination.While microbial treatment did not influence the total biomass,it had a significant impact on the biomass allocation in both the plant species.R.columnifera seeds germinated at both 2-cm and 6-cm depth and did not germinate at 12 cm,while the V.encelioides seeds germinated only at 2 cm and did not germinate at 6-cm or 12-cm seeding depth.Conclusions:While our results are species specific,our results indicate that native soil microbes can potentially improve the seed germination and growth of wildflowers.Our results also indicate the importance of specific seeding depth when sowing wildflower seeds for habitat restoration.
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.
