| Centipegrass is only speceies of Eremochloa which could be used for turfgrass and has a lot of advantages,such as dwarfness,stong stolons,rapid spread,beautiful leaf,plant low,fewer pests and diseases,and low maintenance requirements.So it is widely used in public Greenland,homeyard lawn and erosion conservation.Centipedegrass origin in central China and southern China,,has abundant in the distributed region.The research in China mainly focused on germplasm resources evaluation and preliminary utilization,and has developed some new cultivars including excellent seed propagated cultivars.Howver,the lack of key technique for seed production provent the seed propagated cultivar from the seed production and utilization At present,centipedegrass mainly rely on imports of expensive centipedegrass seed or vegetative propagation mode,which obviously limits the development and utilization of rich germplam of centipedegrass.This study select the seed propagated cultivar E092(1)(bred by institute of Botany,Jiangsu Province and Chinese Academy of Science)as test plant,and conduct three part of research work:(1)The observation of infloresence differentitation and development of centipedegrass;(2)The effect of fertilizer application on centipedegrass seed yield and quality was conducted based on the observation of infloresence differentitation and development;(3)The harvest time on the centipedegrass seed yield and quality was studied.The main result were summaried as following:1.The infloresence differentiation of cetipedegrass were observed periodically throughout the development stages,the whole spike differentiation could be divided into 8 stages:Vegetative stage,elongation stage,bract primordium differentiton stage,spikelet primordium differentiation stage,spikelet differentitation stage,floret differentitation stage,the stage of stamen and pistil primordial formation,flowering stage.The relationships between the infloresence differention and phonological period shows that bract primordium differentiton stage is the key period in which centipedegrass growth from vegetative growth to reproduction growth.2.Fertilization in the spring(10.0 g/m2N、5.0 g/m2P2O5、5.0 g/m2K2O)and summer(2.5g/m2N、2.5g/m2P2O5、2.5g/m2K2O)can result in the highest inflorescence density of centipedegrass(9750 branches/m2),50%higher than that of the control(no fertilization),and seed yield the cetipedegrass can reach to 23.08g/m2,increased by 67%compared to the control.Fertilizer higher than 10.0g/m2N、5.0g/m2 P2O5、5.0g/m2K2O in Spring and summer,or fertilizer higher than 17.5g/m2N、12.5g/m2 P2O5、20.0g/m2K2O within a year will not only decrease the seed inflorence density and the number of seeds,but also remarkablely reduce the seed quality.In addition,ifertilization application had no significant effect on the germination rate,bud length,seed vigor,wheras acid phosphatase improved in different degree compared with the control..3.With the delayed harvest period,the spikelet number per infloresence continued to decrease;spike density,seed setting rate,thousand-grain weight and germination energy began to increase and then decline,while The germination rate was increased and then maintained at a stable trend.The spikelet number perinfloresence,spike density,seed setting rate,thousand-grain weight all reached the highest level in October 29th when≥10℃ accumulated temperature ia high as 5000℃.Germination rate and germination energy has also reached high level.The appropriate seed harvest date for E092(1)centipedegrass should be October 29th in Nanjing areaor when the≥10℃ accumulated temperature is as high as 5000℃,and the seed the yield could reach 34.21 g·m-2. |
