Showing 6 results for Tall Fescue
R. Mohammadi, A. F. Mirlohi,
Volume 7, Issue 2 (7-2003)
Abstract
A symbiotic relationship exists between the endophytic fungi of the genus Neotyphodium and many cool-season grasses. Endophytes can alter the growth as well as morphological and physiological characteristics of the host plant, thereby influencing the persistence and survival rate of infected plants. This study was conducted to evaluate the effects of endophyte on phenotypic characteristics of Iranian tall fescue (Festuca arundinacea Schreb.) and meadow fescue (Festuca pratensis Huds.). The experiment was set up as a completely randomized design with three replications in a factorial arrangement. The first factor was the two plant accessions and the secondary factor was the endophyte-infected and noninfected plants. The results showed that most of phenotypic characteristics significantly altered as a result of endophyte infection in both tall fescue and meadow fescue plants. Results of analysis of variance showed that the influence of endophyte fungus was positive and significant on tiller number, herbage yield, dry crown weight, dry root weight per plant, and crown depth. Also between plant accessions, there were significant differences for dry herbage yield, crown weight, dry root weight per plant, crown depth, and dry matter percentage. Plant by endophyte interaction was highly significant for crown depth and dry root weight per plant. Therefore, eudophytic fungi can be used to improve phenotypic characteristics in these plants.
B. Hatami, A.f. Mirlohi, M.r. Sabzalian,
Volume 10, Issue 2 (7-2006)
Abstract
Endophytic fungi, Neotyphodium spp. symbiotically infect host grasses, Fescue arundinacea Schreb. and F. pratensis Huds. and Mealybug, Phenococcus solani Ferris attacks some forage plants. To evaluate the role of these fungi to control this pest, four genotypes of F. arundinacea and two genotypes of F. pratensis were used. Plant tillers were split into two sections, one section of which was freed from endophyte using a fungicide mixture. The mixture contained 2 grams of active ingredients of Propiconazol and 1 ml of Folicur per liter of water. New tillers from endophyte-infected and endophyte-free plants were transferred into the field. The number of mealybugs was measured after the first visible sign of infestation on roots. To count mealybug, one plant hill of each plot was randomly selected. Hay yield of each plot was measured by clipping the plants 5 cm above ground level. Correlation of hay yield and other growth characteristics with the number of mealybugs on roots as an index for mealybug damage on infested plants was determined. The results indicated that endophyte-free plants were highly infested with mealybug, P. solani compared with endophyte-infected plants that were completely free of P. solani, correlation coefficients showed that there was significant negative correlation between forage yield and mealybug numbers, indicating mealybug damage on infested plants. It seems that endophytic fungi are effective biocontrol factors for some root feeding pest such as mealybug, P. solani.
A. F. Mirlohi, M. R. Sabzalian, M. H. Ehtemam,
Volume 10, Issue 4 (1-2007)
Abstract
In order to evaluate endophyte effect on plant earliness, compatible host-endophyte combinations including four genotypes of tall fescue and two genotypes of meadow fescue were selected and used in this study. One tiller-part of each genotype was treated using a fungicide mixture of Propiconazole and Folicur. New tillers of endophyte-infected and endophyte-free plants were planted in the field according to a complete block design with three replications. The traits including days to head emergence, days to 50% anthesis, days to maturity initiation, number of heads (as a weekly measurement), total seed weight, net seed weight and empty seed weigh were measured. Results showed that endophytes can enhance head emergence, maturity initiation and periodical seed yield. Days to 50% anthesis, and days to maturity initiation were also reduced. Head numbers in some genotypes increased up to 2 times. Increase in net seed yield may show some physiological alterations in plant such as hormonal balance alteration which may provide better seed setting in infected plants. Based on this study, we concluded that endophytic fungi can induce earliness in infected host plants.
M.m Majidi, A Mirlohi,
Volume 12, Issue 46 (1-2009)
Abstract
This experiment was conducted to investigate the genetic diversity, identify traits explaining yield variation, recognize relationships between traits and classify accessions in a Iranian and forign germplasem of tall fescue. Forty six Iranian and foreign tall fescue accessions were surveyed for Phenological, morphological and agronomical characters in a randomized complete block design with three replications in field for 2 years. Significant differences were observed for all of the characters, indicating broad variation in this germplasm. Iranian accessions had a better performance for most of the traits in both years indicating their high potential for developing commercial varieties in breeding programs. Basis on stepwise regression analysis, crown width justified the majority of hay yield variation, followed by establishment rate, percentage of dry matter, height and number of stem. Hence, these characters could be used for selecting high yielding cultivars. Factor analysis revealed 4 factors which explained more than 80 percent of the total variation and confirmed the results of regression analysis. Using UPGMA method, cluster analysis revealed five groups. Accessions with similar country of origin or same ecological conditions were grouped in same cluster. Regarding the morphological characters the best accessions were identified to be used in the further breeding projects.
V Zabihollahi, F Maighany, M Baghestany, M Mirhady,
Volume 13, Issue 47 (4-2009)
Abstract
To study the goosegrass (Eleusine indica (L.) Gaertn.) in tall fescue (Festuca arundinacea Schreb.), an experiment in 15-year old turf was conducted during 2006 in Tehran in Sheikh Fazlollah highway using randomized complete block design with 4 replications in 1*1 m2 plots. Treatments were diclofop methyl at 2.5 and 3 Lha-1, fenoxaprop-p-ethyl at 0.8 and 1 Lha-1, clodinafop propargyl at 0.6 and 0.8 Lha-1, tralkoxydim at 1 and 1.2 Lha-1, sulfosulfuron at 27 and 35 gha-1 and untreated control. All treatments were repeated 3 times during the growing period of goosegrass. The results showed that after the last spraying, diclofop methyl at 2.5 and 3 Lha-1, fenoxaprop-p-ethyl at 0.8 and 1 Lha-1, clodinafop propargyl at 0.6 and 0.8 Lha-1 decreased goosegrass's biomass up to 81, 83.64, 81.26, 78.58, 80.27 and 81.26 percent, respectively and goosegrass's density up to 82.5, 83.13, 79.38, 79.38, 78.75 and 80.63 percent, respectively, without significant differences. Treatment after 2 times of spraying controlled goosegrass more than 80 percent. Tralkoxydim and sulfosulfuron decreased goosegrass' biomas and density about 70 and 60 percent, respectively. One week after the last spraying, diclofop methyl, fenoxaprop-p-ethyl and clodinafop propargyl treatments did not decrease tall fescue's biomass without significant differences with untreated control. Turf biomass was decreased by tralkoxydim at 1 and 1.2 Lha-1 and sulfosulfuron at 27 and 35 gha-1, by 37.54, 36.79, 40.48 and 48.55 percent, respectively. Herbicide treatments made visual rating by 49.38, 48.75, 48.75 and 50.63 percent, respectively. Overall, diclofop methyl at 2.5 Lha-1, fenoxaprop-p-ethyl at 0.8 Lha-1 and clodinafop propargyl at 0.6 Lha-1 can be recommended for goosegrass control in tall fescue because of insignificant differences between both their doses, bio-environmental problems, costs, and no damage to tall fescue.
F. Hosseini, M. R. Mosaddeghi, M. A. Hajabbasi, M. R. Sabzalian, M. Soleimani, M. Sepehri,
Volume 21, Issue 2 (8-2017)
Abstract
Soil water repellency can affect several soil properties such as aggregate stability. Soil texture and organic matter are two main internal factors responsible for the variability of soil water repellency. Major sources of organic matter in soil include plant residues, and exudates of plant roots and soil microorganisms. Tall fescue (Festuca arundinacea Schreb.) as an important cool-season perennial forage grass is usually infected by a fungal endophyte (Epichloë coenophiala) which often enhances resistance to biotic and abiotic stresses as well as altering the litter decomposition rate and soil properties. In this study, the effects of endophyte-infected (E+) and endophyte-free (E−) tall fescue residues (in three different levels of 0, 1 and 2%) on soil organic carbon, basal microbial respiration, water-dispersible clay and water repellency index (determined by intrinsic sorptivity method) were investigated in four texturally-different soils in the laboratory. E+ and E− tall fescue residues were completely mixed with moist soil samples and then were incubated at 25 °C. During two months of incubation period, the amended soil samples were subjected to 10 wetting and drying cycles and then, the above-mentioned soil properties were measured. The results indicated that soil organic carbon and water-dispersible clay were greater, while basal soil respiration and repellency index were lower in fine-textured soils. Water repellency index was increased by production of hydrophobic substances (for the rate of 1%) and was reduced by induced greater soil porosity (for the rate of 2%). Presence of endophyte in plant residues had no significant effect on water sorptivity, ethanol sorptivity and water repellency index; nevertheless, E+ residues increased soil organic carbon and decreased water-dispersible clay significantly. Overall, it is concluded that tall fescue residues, especially those with E+, can improve soil physical quality due to improving soil organic carbon storage and water repellency index and decreasing water-dispersible clay (as an index for aggregate instability). These E+ species and the residues have great potential to be used in sustainable soil conservational managements.
