| Eulaliopsis binata is a valuable apomictic resource in Graminea. Two ecotypes of E. binata with different leaf shape were artificially or open pollinated after emasculation to investigate their apomixis degree and genetic pathway. Pollen vigor was tested by germination in vitro; In vivo germination on stigma were observed by fluorescence staining method. The relative DNA content and ploidy of the embryo and endosperm cell in ripe seed were examined by Flow Cytometry. Chromosome number of root tips were calculated. The results are as follows:1 In slender-leaf type of E. binata, the seed setting in treatment of no pollination (bagging after emasculation) reached 12.2%, while that in treatment of cross-pollination was 11.23%, and in another treatment of no pollination (removal of stigma) was 10.78%. In treatment of open pollination after emasculation the seed setting was 12.38%; In red type E. binata, the seed setting of emasculation by bagging was 9.38%, the seed setting of cross-pollination was 8.88%, the seed setting of removal of stigma was 9.29%, the seed setting of emasculation comparison was 9.13%; Variances analysis suggest that there are no significant difference among the seed setting of emasculation by bagging, cross-pollination and removal of stigma, respectively as compared with control in both ecotypes.2 Fresh pollen grains were germinated in sugar solution. The pollen germination rate of slender leaf type E. binata is up to 28.1%, the pollen germination rate of red pole type E. binata is up to 34.13%, the both have normal activity; Vigor of pollen of red-haulm type E. binata that was kept at low temperature (4癈) after dryness is 24.17% after two days, the vigor is 15.31% after four days, the vigor is 10.98% after.keeping for six days.3 Pistil was stained with aniline blue at l-5h after pollinating, then wholly observed on,fluorescence microscope and ordinary microscope respectively. The result indicated the pollens of E. binata had poor adherences to stigma. Though pollen grains could germinate on stigma but the pollen tube could not stretch into stigma further more. After 5h, the pollen tubes prolonged and twisted on the stigma surface and rare pollen tubes (<5%) could enter stigma and style.4 Using leaves of seedling as control, C values of seeds in two ecotypes E. binata were screened by Partec Flow Cytometry. The observed three peaks in seeds of slender leaf type revealed relative three types of C value as 2C:3C:4C. In red-haulm type, only two peaks were screened indicated two types of C value in 2C:4C. These results were quite different from normal sexual plant in which the ripe seeds produce two relative C value as 2C:3C, standing for zygote (2n) and endosperm (3n)..5 The methods of chromosome identify of root tip of E. binata: the suitable medium of seed germination is river sand, the best time for root tip cell division are am 9-11 and pm 4-6; the pre-treatment need 4hrs in p-Dichlorobenzene saturated solution + a -Bromonaphthalene, it is good with 15-25min that using the hydrochloric acid to solve roots; The dyeing time of improved fuchsin need 10-15 min. The numbers of chromosome of E. binata seed is 36.Above results provides evidences in genetics> cytology and seed ploidy to support the opinion that E. binata is an apomictic plant in Graminea. The seed could be produced without pollination and the embryo and endosperm could develop autonomously. Two kinds of ecotype E. binata have different apomixis degree. The red-haulm type had highly apomixis characteristic, its seed formed without male gamete participation, and its embryo and endosperm's C value is 2C:4C. The slender leaf type should be facultative apomixis.Its embryo and endosperm's relative C value is 2C:3C:4C. E. binata possess vigorous pollen which could germinate normally and might act as a potential valuable donor for apomixis gene. The chromosome number of E. binata is 36.
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