Wastewater stabilization ponds generate low cost by-products that are useful for agriculture. The utilization of these by-products for soil amendment and as a source of nutrients for plants requires a high level of sa...Wastewater stabilization ponds generate low cost by-products that are useful for agriculture. The utilization of these by-products for soil amendment and as a source of nutrients for plants requires a high level of sanitation and stabilization of the organic matter, to maintain acceptable levels of soil, water and air quality. In this study, two aquaculture wastewater treatment systems; recirculating system and a floating plant bed system were designed to improve the quality of irrigation water in local communities with low income. In both systems the grass species Lolium perenne Lam was used as a plant biofilter while vegetable specie Amaranthus viridis was used to evaluate the performance of the system and the suitability of the phyto-treated water for irrigation. It was found that the harmful material removal rate for recirculating system was 88.9% for TAN (total ammonia nitrogen), 90% for NO2--N, 64.8% for NO3--N while for floating plant bed system 82.7% for TAN, 82% for NO2--N and 60.5% for NO3--N. Comparative analysis of the efficiency of waste element removal between the two systems revealed that both systems performed well, however, plant growth was not robust for floating plant bed system while recirculating system is energy consuming. Although both systems did not attain sufficient levels of TN (total nitrogen) and TP (total phosphorus) load reduction, the treatment with L. perenne remarkably improved the irrigation water quality. A. viridis plants irrigated with the phyto-treated discharge water had lesser concentrations of heavy metals in their tissues compared to those irrigated with untreated discharge. The control plants irrigated with untreated discharge were also found to be highly lignified with few stems and small leaves.展开更多
[Objective] The aim was to restore heavy metal pollution of urban sewage river sediment by using Lolium perenne.[Method] Through cultivation test,the phytoremediation of heavy metal pollution in river sediment by L.pe...[Objective] The aim was to restore heavy metal pollution of urban sewage river sediment by using Lolium perenne.[Method] Through cultivation test,the phytoremediation of heavy metal pollution in river sediment by L.perenne was analyzed from the aspects of removal effect,optimal removal time and the changes of sucrase activity,urease activity and microbe quantity.[Result] After planting L.perenne for three months,Ni content in sediment was basically stable,while the removal effect of Cr and Mn in sediment was optimal,and the removal rate of Cr reached the maximum value (57.1%).After 4-5 months,sucrase and urease activity were 4.59 and 10.34 times the previous activity respectively.In addition,the quantity of bacteria and fungi was 2-3 times the previous quantity after 3-4 months.In a word,L.perenne had obvious effects on the removing of heavy metal,improvement of enzyme activity and microbe quantity in polluted river sediment,and the optimal planting time of L.perenne was four months.[Conclusion] The study could provide theoretical foundations for the control of polluted sediment in river.展开更多
A method of Agrobacterium tumefaciens mediated transformation for perennial ryegrass was developed using the calli of ryegrass derived from mature enrbryos. The calli were inoculated with a disarmed A. tumefaciens str...A method of Agrobacterium tumefaciens mediated transformation for perennial ryegrass was developed using the calli of ryegrass derived from mature enrbryos. The calli were inoculated with a disarmed A. tumefaciens strain EHA105 harboring binary vector p2328. Vector p2328 contained transcription factor DREB1B and neomycin phosphotransferase (npt H) genes which were driven by promoters of rd29B and CaMV35S, respectively. The inoculated calli were selected on paromomycin- or kanamycin-containing media till the established plants being transferred to soil. Six tmnsgenic plants with DREB1B had been obtained from perennial ryegrass strain Tove. PCR and Southern-blotting showed that npt Ⅱ and DREBIB genes were integrated in perennial ryegrass genome. Stress treatment confirmed that transgenic plants with higher drought tolerance were obtained.展开更多
Italian ryegrass is an annual/biennial grass that is typically used as a pasture crop or a cover crop along roadsides, rights-of-way, and industrial areas. Glyphosate-resistant (GR) Italian ryegrass populations have b...Italian ryegrass is an annual/biennial grass that is typically used as a pasture crop or a cover crop along roadsides, rights-of-way, and industrial areas. Glyphosate-resistant (GR) Italian ryegrass populations have been documented around the world, mostly in orchard and vineyard situations. The first evidence of evolved GR Italian ryegrass in row/agronomic crops was reported from Washington County, Mississippi in 2005. GR Italian ryegrass populations can jeopardize preplant burndown options in reduced-tillage crop production systems, thereby, delaying planting operations. The effects of competition of Italian ryegrass on crop growth and yield are poorly understood. A field study was conducted in the 2012 growing season and repeated in the 2013 growing season. GR and susceptible (GS) Italian ryegrass populations were established in the greenhouse and transplanted in prepared corn row beds in the fall of 2011 and 2012 at 0, 1, 2, 3, and 4 plants·meter> of crop row. Italian ryegrass plants overwintered and developed over the following spring-summer. Glyphosate was applied at 1.26 kg·ae/ha (1.5× of labeled rate) in the spring to burndown the Italian ryegrass plants and corn was planted into the ryegrass residue 2 - 3 wk later. Current corn production practices were followed. Corn density (early and late season), height (early season), and yield and Italian ryegrass biomass (early-mid season) measurements were recorded during both years. Corn height was greater in 2012 than that in 2013 at comparable stages of the growing season, due to a cooler and wetter early season in 2013 than that in 2012. Averaged across weed densities, corn density (both early and late season) and yield were higher in the GS than those in the GR population, but Italian ryegrass biomass was similar for both populations. Averaged across Italian ryegrass populations, corn density (both early and late season), and yield were inversely proportional to Italian ryegrass density. In summary, Italian ryegrass significantly reduced corn density and yield and reduction was greater with the GR than that with the GS population. Studies are underway to study inter population competition in Italian ryegrass and investigate allelopathic effects of Italian ryegrass on selected crops.展开更多
Antifreeze proteins(AFP) are produced by certain plants, animals, fungi and bacteria that enable them to survive upon extremely low temperature. Perennial rye grass, Lolium perenne, was reported to possess AFP which...Antifreeze proteins(AFP) are produced by certain plants, animals, fungi and bacteria that enable them to survive upon extremely low temperature. Perennial rye grass, Lolium perenne, was reported to possess AFP which protects them from cold environments. In the present investigation, we isolated AFP gene from L. perenne and expressed it in tomato plants to elucidate its role upon chilling stress. The T1 transgenic tomato lines were selected and subjected to molecular, biochemical and physiological analyses. Stable integration and transcription of Lp AFP in transgenic tomato plants was confirmed by Southern blot hybridization and RT-PCR, respectively. Physiological analyses under chilling conditions showed that the chilling stress induced physiological damage in wild type(WT) plants, while the transgenic plants remained healthy. Total sugar content increased gradually in both WT and transgenic plants throughout the chilling treatment. Interestingly, transgenic plants exhibited remarkable alterations in terms of relative water content(RWC) and electrolyte leakage index(ELI) than those of WT. RWC increased significantly by 3-fold and the electrolyte leakage was reduced by 2.6-fold in transgenic plants comparing with WT. Overall, this report proved that Lp AFP gene confers chilling tolerance in transgenic tomato plants and it could be a potential candidate to extrapolate the chilling tolerance on other chilling-sensitive food crops.展开更多
Use of individual plants as experimental units may be necessary when resources are limited, but inter-plant variation risks obscuring differences among treatments. Experiments were undertaken to measure the effects of...Use of individual plants as experimental units may be necessary when resources are limited, but inter-plant variation risks obscuring differences among treatments. Experiments were undertaken to measure the effects of seed size on seedling size and response to applied nitrogen of annual ryegrass (Lolium multiflorum L.) harvested six or nine weeks after emergence. In two series of experiments, shoot and root dry weights of seedlings increased respectively at means of 53 - 61 and 29 - 30 mg·mg-1 increase in mean seed weight. Between the largest and smallest seed sizes used in this study, there was 83% difference in shoot weight at harvest six weeks after emergence and 22% difference with harvest nine weeks after emergence. Nitrogen (N) application, in comparison, increased shoot dry weights by averages of 69% and 77% with harvests at six or nine weeks, respectively. Dry mass response to N application was similar across seed size categories in shoots or roots. A mean 30% of total seedling-N was retained in roots. Nitrogen utilization efficiency for shoot growth (increase in shoot growth per unit increase in shoot N capture) ranged from 64 mg·mg-1 with harvest six weeks after emergence to 114 mg·mg-1 with harvest at nine weeks after emergence. Delay in seedling harvest from six to nine weeks post-emergence and use of closely-graded seed can reduce variation in individual seedling size and contribute to reduction in random variation in small-scale experiments.展开更多
Objective This work is an evaluation of the efficiency of a sand-gravel or unwoven fabric bed system and Lolium perenne Lam as plant biofilter in the reduction of solids and nutrients removal from aquaculture discharg...Objective This work is an evaluation of the efficiency of a sand-gravel or unwoven fabric bed system and Lolium perenne Lam as plant biofilter in the reduction of solids and nutrients removal from aquaculture discharge water. Methods The fzrst step consisted of the collection of wastewater in the tank and the distribution at three different hydraulic loading regimes (0.5, 1, 1.5 L/hour) to the different experimental systems. The second step was to evaluate the performance of the different systems. The fzrst system consisted of a bucket filled with a substrate of sand/gravel (20 cm in depth), on the bottom of which was a 80 mesh/inch2 of nylon (S1); the second was similar, but was planted with Lolium perenne lam (S2); the third was planted with a grass plate consisting of 7 layers of unwoven fabric planted with L. perenne (S3). Results The second system showed the best performance in reducing solids as well as in nutrients (TN, TP, and COD) reduction. The removal rates for TS, TN, and TP were negatively correlated with the loading regimes, with 0.5 L/hour being the most efficient and thus taken as the reference. Conclusions Solids management using a sand/gravel substrate as bed culture and Lolium perenne L. as plant biofilter has proved to be an efficient technique for solids reduction with low operating cost. This grass plays an important role in wastewater eco-treatment by absorbing dissolved pollutants (TAN) as nutrients for its growth.展开更多
The paper aimed to study the effects of nitrogen fertilization on the yield and some plant characteristics of perennial ryegrass (Lolium perenne L.). The study was conducted at Agricultural Research and Application Ce...The paper aimed to study the effects of nitrogen fertilization on the yield and some plant characteristics of perennial ryegrass (Lolium perenne L.). The study was conducted at Agricultural Research and Application Center of the Faculty of Agriculture in Igdir University in 2013. In the experiment, eight levels of fertilizers: 0, 10.0, 20.0, 30.0, 40.0, 50.0, 60.0 and 70.0 kg N/ha per month were applied in perennial ryegrass (Lolium perenne L.) during the sixth growing season. A randomized complete block with three replications was used as the experimental design. Nitrogen application affected plant height, green grass yield, plant covering rate, canopy color and turfgrass quality values of perennial ryegrass positively. In both monthly and as the average of nitrogen application, times of application (spring, summer and fall) caused the most uniform turfgrass quality and establishment. Results indicated that although a significant impact was on the character investigated, such as the leaf length, green grass yield, plant cover ratio, canopy color and turfgrass quality, the doses of nitrogen fertilizer have created close to each other in groups. In the stand point of view of all characters, N1, N2 and N3 were located in first group, N4 and N5 in the second group, N6 and N7 in the third group, expect for control (N0). It can be concluded that 40.0-50.0 kg N/ha per month may be more suitable to be used in ryegrass production in the landscape.展开更多
The good understanding of the mechanisms of resistance to herbicides in weeds is a necessity to implement sustainable weed management strategies. Here, a study was conducted to characterize the molecular bases of resi...The good understanding of the mechanisms of resistance to herbicides in weeds is a necessity to implement sustainable weed management strategies. Here, a study was conducted to characterize the molecular bases of resistance to acetyl coenzyme A carboxylase (ACCase) and acetolactate synthase (ALS) inhibiting herbicides in Lolium rigidum populations from Tunisia. Nine Lolium rigidum (ryegrass) populations collected in wheat fields from Northern Tunisia were investigated for their resistance to two ACCase-inhibiting herbicides and an ALS-inhibiting herbicide. All populations were tested in the greenhouse in pots using the commercial dose to determine resistance status. Survival plants were also tested for the presence of two ACCase (L 1781 and N2041) and two ALS (P197 and W574) mutant resistant alleles using molecular markers. Resistance to ACCase-inhibiting herbicides was found in all tested populations. Comparison of the results from herbicide sensitivity bioassays with genotyping indicated that more than 80% of the plants resistant to ACC-inhibiting herbicides would be resistant via increased herbicide metabolism. However, ALS-inhibiting herbicides are still more or less controlling ACCase resistant populations, so indicating that the selection process of resistance is ongoing. Target-site resistance appears to be the major mechanism for these early cases of ALS inhibitor resistance. This study reported the first case of resistance to ALS-inhibiting herbicides in ryegrass in Tunisia, and investigated the molecular bases of this resistance. It establishes the clear importance of non target-site resistance to ACCase- and/or ALS-inhibiting herbicides.展开更多
[Objectives]This study was conducted to obtain the best solution for sterilizing tall fescue(Festuca arundinacea)and ryegrass(Lolium perenne)seeds by heating in a water bath for a short time.[Methods]The tall fescue a...[Objectives]This study was conducted to obtain the best solution for sterilizing tall fescue(Festuca arundinacea)and ryegrass(Lolium perenne)seeds by heating in a water bath for a short time.[Methods]The tall fescue and ryegrass seeds infected with endophytic fungi were sterilized by heating in a water bath to compare seed germination and initial growth of turfgrass seedlings under different treatment time.[Results]Sterilization in a 60℃water bath for 20 and 30 min both inhibited the germination of tall fescue and ryegrass seeds,while the 20 min treatment did not significantly affect the lengths of stems,leaves and roots of seedlings.The 20 min water bath sterilization treatment had no effects on the plant heights and biomass of the two turfgrass seedlings and the tiller number of ryegrass,but sterilization for 30 min significantly reduced the aboveground and total biomass of seedlings and the tiller number of ryegrass.[Conclusions]Sterilization in a water bath at 60℃ for 20 min achieved rapid sterilization in a short time,without significantly negatively affecting the growth of seedlings.展开更多
The genetic variation of Italian ryegrass (Lolium multiflorum Lain.) and westerwolds ryegrass (L. westerwoldicum Breakw.) was investigated in eight tetraploid cultivars originated from Poland. The 337 individual s...The genetic variation of Italian ryegrass (Lolium multiflorum Lain.) and westerwolds ryegrass (L. westerwoldicum Breakw.) was investigated in eight tetraploid cultivars originated from Poland. The 337 individual seedlings, cultivated in uniform greenhouse conditions, were tested with horizontal gel electrophoresis according to five enzyme systems: diaforase (DIA), superoxide dismutase (SOD), glutamate oxalacetate transaminase (GOT), peroxidise (PX) and phosphogluco isomerise (PGI), which were used to array allelic diversity at five polymorphic loci. The estimation of genetic diversity in 64 plants of the same cultivars was studied using inter simple sequence repeats (ISSRs) as molecular marker. The genetic variation described by ISSR suggests that the polymorphism detected appears to be poorly informative at the taxonomic level. For statistical analysis, unweighted pair group method with arithmetic mean (UPGMA) based dendrograms and minimum spanning trees were constructed using Nei's distance and Jaccard' s similarity coefficient.展开更多
基金Project supported by the Technology Department Zhejiang Province of China(No. 2005C22060).
文摘Wastewater stabilization ponds generate low cost by-products that are useful for agriculture. The utilization of these by-products for soil amendment and as a source of nutrients for plants requires a high level of sanitation and stabilization of the organic matter, to maintain acceptable levels of soil, water and air quality. In this study, two aquaculture wastewater treatment systems; recirculating system and a floating plant bed system were designed to improve the quality of irrigation water in local communities with low income. In both systems the grass species Lolium perenne Lam was used as a plant biofilter while vegetable specie Amaranthus viridis was used to evaluate the performance of the system and the suitability of the phyto-treated water for irrigation. It was found that the harmful material removal rate for recirculating system was 88.9% for TAN (total ammonia nitrogen), 90% for NO2--N, 64.8% for NO3--N while for floating plant bed system 82.7% for TAN, 82% for NO2--N and 60.5% for NO3--N. Comparative analysis of the efficiency of waste element removal between the two systems revealed that both systems performed well, however, plant growth was not robust for floating plant bed system while recirculating system is energy consuming. Although both systems did not attain sufficient levels of TN (total nitrogen) and TP (total phosphorus) load reduction, the treatment with L. perenne remarkably improved the irrigation water quality. A. viridis plants irrigated with the phyto-treated discharge water had lesser concentrations of heavy metals in their tissues compared to those irrigated with untreated discharge. The control plants irrigated with untreated discharge were also found to be highly lignified with few stems and small leaves.
基金Supported by National Natural Science Foundation of China(50908159 )Major State Basic Research Development Program(973 Program)(2007CB407306)
文摘[Objective] The aim was to restore heavy metal pollution of urban sewage river sediment by using Lolium perenne.[Method] Through cultivation test,the phytoremediation of heavy metal pollution in river sediment by L.perenne was analyzed from the aspects of removal effect,optimal removal time and the changes of sucrase activity,urease activity and microbe quantity.[Result] After planting L.perenne for three months,Ni content in sediment was basically stable,while the removal effect of Cr and Mn in sediment was optimal,and the removal rate of Cr reached the maximum value (57.1%).After 4-5 months,sucrase and urease activity were 4.59 and 10.34 times the previous activity respectively.In addition,the quantity of bacteria and fungi was 2-3 times the previous quantity after 3-4 months.In a word,L.perenne had obvious effects on the removing of heavy metal,improvement of enzyme activity and microbe quantity in polluted river sediment,and the optimal planting time of L.perenne was four months.[Conclusion] The study could provide theoretical foundations for the control of polluted sediment in river.
基金Supported by the National Natural Science Foundation of China(30170589)and the National Special Project for Research and Industrialization of Transgenic Plants (J-2002-B-006). Acknowledgements: We are grateful to Dr. Zhang Xiao-dong of Beijing Academy of Agricultural and Forestry Sciences for donating gene DRB1B and Agrobacterium tumefaciens EHA105. We thank Ms. Yang Hong of Chengdu Institute of Biology, Chinese Academy of Sciences, for conducting much work of tissue culture. We also thank Center for Application of Molecular Biology to International A griculture (CAMBIA), Australia for permission of use pCAMBIA2301.
文摘A method of Agrobacterium tumefaciens mediated transformation for perennial ryegrass was developed using the calli of ryegrass derived from mature enrbryos. The calli were inoculated with a disarmed A. tumefaciens strain EHA105 harboring binary vector p2328. Vector p2328 contained transcription factor DREB1B and neomycin phosphotransferase (npt H) genes which were driven by promoters of rd29B and CaMV35S, respectively. The inoculated calli were selected on paromomycin- or kanamycin-containing media till the established plants being transferred to soil. Six tmnsgenic plants with DREB1B had been obtained from perennial ryegrass strain Tove. PCR and Southern-blotting showed that npt Ⅱ and DREBIB genes were integrated in perennial ryegrass genome. Stress treatment confirmed that transgenic plants with higher drought tolerance were obtained.
文摘Italian ryegrass is an annual/biennial grass that is typically used as a pasture crop or a cover crop along roadsides, rights-of-way, and industrial areas. Glyphosate-resistant (GR) Italian ryegrass populations have been documented around the world, mostly in orchard and vineyard situations. The first evidence of evolved GR Italian ryegrass in row/agronomic crops was reported from Washington County, Mississippi in 2005. GR Italian ryegrass populations can jeopardize preplant burndown options in reduced-tillage crop production systems, thereby, delaying planting operations. The effects of competition of Italian ryegrass on crop growth and yield are poorly understood. A field study was conducted in the 2012 growing season and repeated in the 2013 growing season. GR and susceptible (GS) Italian ryegrass populations were established in the greenhouse and transplanted in prepared corn row beds in the fall of 2011 and 2012 at 0, 1, 2, 3, and 4 plants·meter> of crop row. Italian ryegrass plants overwintered and developed over the following spring-summer. Glyphosate was applied at 1.26 kg·ae/ha (1.5× of labeled rate) in the spring to burndown the Italian ryegrass plants and corn was planted into the ryegrass residue 2 - 3 wk later. Current corn production practices were followed. Corn density (early and late season), height (early season), and yield and Italian ryegrass biomass (early-mid season) measurements were recorded during both years. Corn height was greater in 2012 than that in 2013 at comparable stages of the growing season, due to a cooler and wetter early season in 2013 than that in 2012. Averaged across weed densities, corn density (both early and late season) and yield were higher in the GS than those in the GR population, but Italian ryegrass biomass was similar for both populations. Averaged across Italian ryegrass populations, corn density (both early and late season), and yield were inversely proportional to Italian ryegrass density. In summary, Italian ryegrass significantly reduced corn density and yield and reduction was greater with the GR than that with the GS population. Studies are underway to study inter population competition in Italian ryegrass and investigate allelopathic effects of Italian ryegrass on selected crops.
基金supported by the Senior Research Fellowship from the Council of Scientific and Industrial Research-Human Resource Development Group (CSIRHRDG), New Delhi, India (09/472(0164)/2012-EMR-I)the funds from the University Grants Commission-Special Assistance Programme (UGC-SAP)the Department of Science and Technology-Fund for Improvement of S&T Infrastructure (DST-FIST), Bharathiar University, Tamil Nadu, India
文摘Antifreeze proteins(AFP) are produced by certain plants, animals, fungi and bacteria that enable them to survive upon extremely low temperature. Perennial rye grass, Lolium perenne, was reported to possess AFP which protects them from cold environments. In the present investigation, we isolated AFP gene from L. perenne and expressed it in tomato plants to elucidate its role upon chilling stress. The T1 transgenic tomato lines were selected and subjected to molecular, biochemical and physiological analyses. Stable integration and transcription of Lp AFP in transgenic tomato plants was confirmed by Southern blot hybridization and RT-PCR, respectively. Physiological analyses under chilling conditions showed that the chilling stress induced physiological damage in wild type(WT) plants, while the transgenic plants remained healthy. Total sugar content increased gradually in both WT and transgenic plants throughout the chilling treatment. Interestingly, transgenic plants exhibited remarkable alterations in terms of relative water content(RWC) and electrolyte leakage index(ELI) than those of WT. RWC increased significantly by 3-fold and the electrolyte leakage was reduced by 2.6-fold in transgenic plants comparing with WT. Overall, this report proved that Lp AFP gene confers chilling tolerance in transgenic tomato plants and it could be a potential candidate to extrapolate the chilling tolerance on other chilling-sensitive food crops.
文摘Use of individual plants as experimental units may be necessary when resources are limited, but inter-plant variation risks obscuring differences among treatments. Experiments were undertaken to measure the effects of seed size on seedling size and response to applied nitrogen of annual ryegrass (Lolium multiflorum L.) harvested six or nine weeks after emergence. In two series of experiments, shoot and root dry weights of seedlings increased respectively at means of 53 - 61 and 29 - 30 mg·mg-1 increase in mean seed weight. Between the largest and smallest seed sizes used in this study, there was 83% difference in shoot weight at harvest six weeks after emergence and 22% difference with harvest nine weeks after emergence. Nitrogen (N) application, in comparison, increased shoot dry weights by averages of 69% and 77% with harvests at six or nine weeks, respectively. Dry mass response to N application was similar across seed size categories in shoots or roots. A mean 30% of total seedling-N was retained in roots. Nitrogen utilization efficiency for shoot growth (increase in shoot growth per unit increase in shoot N capture) ranged from 64 mg·mg-1 with harvest six weeks after emergence to 114 mg·mg-1 with harvest at nine weeks after emergence. Delay in seedling harvest from six to nine weeks post-emergence and use of closely-graded seed can reduce variation in individual seedling size and contribute to reduction in random variation in small-scale experiments.
基金supported by Zhejiang Provincial Technology Department, China (No. 2005C22060).
文摘Objective This work is an evaluation of the efficiency of a sand-gravel or unwoven fabric bed system and Lolium perenne Lam as plant biofilter in the reduction of solids and nutrients removal from aquaculture discharge water. Methods The fzrst step consisted of the collection of wastewater in the tank and the distribution at three different hydraulic loading regimes (0.5, 1, 1.5 L/hour) to the different experimental systems. The second step was to evaluate the performance of the different systems. The fzrst system consisted of a bucket filled with a substrate of sand/gravel (20 cm in depth), on the bottom of which was a 80 mesh/inch2 of nylon (S1); the second was similar, but was planted with Lolium perenne lam (S2); the third was planted with a grass plate consisting of 7 layers of unwoven fabric planted with L. perenne (S3). Results The second system showed the best performance in reducing solids as well as in nutrients (TN, TP, and COD) reduction. The removal rates for TS, TN, and TP were negatively correlated with the loading regimes, with 0.5 L/hour being the most efficient and thus taken as the reference. Conclusions Solids management using a sand/gravel substrate as bed culture and Lolium perenne L. as plant biofilter has proved to be an efficient technique for solids reduction with low operating cost. This grass plays an important role in wastewater eco-treatment by absorbing dissolved pollutants (TAN) as nutrients for its growth.
文摘The paper aimed to study the effects of nitrogen fertilization on the yield and some plant characteristics of perennial ryegrass (Lolium perenne L.). The study was conducted at Agricultural Research and Application Center of the Faculty of Agriculture in Igdir University in 2013. In the experiment, eight levels of fertilizers: 0, 10.0, 20.0, 30.0, 40.0, 50.0, 60.0 and 70.0 kg N/ha per month were applied in perennial ryegrass (Lolium perenne L.) during the sixth growing season. A randomized complete block with three replications was used as the experimental design. Nitrogen application affected plant height, green grass yield, plant covering rate, canopy color and turfgrass quality values of perennial ryegrass positively. In both monthly and as the average of nitrogen application, times of application (spring, summer and fall) caused the most uniform turfgrass quality and establishment. Results indicated that although a significant impact was on the character investigated, such as the leaf length, green grass yield, plant cover ratio, canopy color and turfgrass quality, the doses of nitrogen fertilizer have created close to each other in groups. In the stand point of view of all characters, N1, N2 and N3 were located in first group, N4 and N5 in the second group, N6 and N7 in the third group, expect for control (N0). It can be concluded that 40.0-50.0 kg N/ha per month may be more suitable to be used in ryegrass production in the landscape.
文摘The good understanding of the mechanisms of resistance to herbicides in weeds is a necessity to implement sustainable weed management strategies. Here, a study was conducted to characterize the molecular bases of resistance to acetyl coenzyme A carboxylase (ACCase) and acetolactate synthase (ALS) inhibiting herbicides in Lolium rigidum populations from Tunisia. Nine Lolium rigidum (ryegrass) populations collected in wheat fields from Northern Tunisia were investigated for their resistance to two ACCase-inhibiting herbicides and an ALS-inhibiting herbicide. All populations were tested in the greenhouse in pots using the commercial dose to determine resistance status. Survival plants were also tested for the presence of two ACCase (L 1781 and N2041) and two ALS (P197 and W574) mutant resistant alleles using molecular markers. Resistance to ACCase-inhibiting herbicides was found in all tested populations. Comparison of the results from herbicide sensitivity bioassays with genotyping indicated that more than 80% of the plants resistant to ACC-inhibiting herbicides would be resistant via increased herbicide metabolism. However, ALS-inhibiting herbicides are still more or less controlling ACCase resistant populations, so indicating that the selection process of resistance is ongoing. Target-site resistance appears to be the major mechanism for these early cases of ALS inhibitor resistance. This study reported the first case of resistance to ALS-inhibiting herbicides in ryegrass in Tunisia, and investigated the molecular bases of this resistance. It establishes the clear importance of non target-site resistance to ACCase- and/or ALS-inhibiting herbicides.
基金the National Natural Science Foundation of China(31870484).
文摘[Objectives]This study was conducted to obtain the best solution for sterilizing tall fescue(Festuca arundinacea)and ryegrass(Lolium perenne)seeds by heating in a water bath for a short time.[Methods]The tall fescue and ryegrass seeds infected with endophytic fungi were sterilized by heating in a water bath to compare seed germination and initial growth of turfgrass seedlings under different treatment time.[Results]Sterilization in a 60℃water bath for 20 and 30 min both inhibited the germination of tall fescue and ryegrass seeds,while the 20 min treatment did not significantly affect the lengths of stems,leaves and roots of seedlings.The 20 min water bath sterilization treatment had no effects on the plant heights and biomass of the two turfgrass seedlings and the tiller number of ryegrass,but sterilization for 30 min significantly reduced the aboveground and total biomass of seedlings and the tiller number of ryegrass.[Conclusions]Sterilization in a water bath at 60℃ for 20 min achieved rapid sterilization in a short time,without significantly negatively affecting the growth of seedlings.
文摘The genetic variation of Italian ryegrass (Lolium multiflorum Lain.) and westerwolds ryegrass (L. westerwoldicum Breakw.) was investigated in eight tetraploid cultivars originated from Poland. The 337 individual seedlings, cultivated in uniform greenhouse conditions, were tested with horizontal gel electrophoresis according to five enzyme systems: diaforase (DIA), superoxide dismutase (SOD), glutamate oxalacetate transaminase (GOT), peroxidise (PX) and phosphogluco isomerise (PGI), which were used to array allelic diversity at five polymorphic loci. The estimation of genetic diversity in 64 plants of the same cultivars was studied using inter simple sequence repeats (ISSRs) as molecular marker. The genetic variation described by ISSR suggests that the polymorphism detected appears to be poorly informative at the taxonomic level. For statistical analysis, unweighted pair group method with arithmetic mean (UPGMA) based dendrograms and minimum spanning trees were constructed using Nei's distance and Jaccard' s similarity coefficient.