Studies On Allelopathic Effects Of Cenchrus Pauciflorus On Oats

Cenchrus pauciflorus Benth., native to North America, is an annual herb of Cenchrus of Gramineae. Cenchrus pauciflorus Benth. as one of the malignant invasion plants in our country, has caused serious influence on economic development and biodiversity. This article taking Cenchrus pauciflorus Benth. as donor materials, oats as receptor plant, studied the influence of different concentration of leaching solution of Cenchrus pauciflorus Benth. in different growth periods on the oat seed germination, seedling growth and physiological and biochemical indexes. It aims to explore the allelopathy of Cenchrus pauciflorus Benth., in order to provide the basis for further investigate of the invasion mechanism of Cenchrus pauciflorus Benth. and effective prevention and control, rational utilization of Cenchrus pauciflorus Benth..This experiment preliminarily studied the allelopathy of Cenchrus pauciflorus Benth. on oats through petri dish filter paper method and indoor potted method. The Results indicated that:The effects of leaching solution of the same growth period Cenchrus pauciflorus Benth. at different concentrations on the oat seed germination and seedling growth were different. The inhibitory effect of leaching solution at low concentration on the oat seed germination and seedling growth was weak, and allelopathic inhibition was enhanced as concentration of leaching solution increased.The inhibition of leaching solution of Cenchrus pauciflorus Benth. on the oat seed germination and seedling growth was enhanced gradually with the extending of growth period of Cenchrus pauciflorus Benth., and the strength of allelopathic inhibition was aging period> grain filling stage> seedling period.With respect to the stem portion, oat roots were more sensitive to leaching solution of Cenchrus pauciflorus Benth..Cenchrus pauciflorus Benth. of the same growth period, its inhibition on physiological and biochemical characteristics of oat seedlings increased with the concentration of the leaching solution increasing. With the increasing of leaching solution concentration, cell membrane permeability of oat seedlings increased gradually, the chlorophyll content gradually decreased, MDA and proline content increased. With the increasing of concentration of leaching solution of Cenchrus pauciflorus Benth. in seedling stage and the extension of processing time, the soluble protein content and POD activity of oat seedlings increased, soluble sugar content, SOD and CAT activity increased and then decreased. With the increasing of concentration of leaching solution of Cenchrus pauciflorus Benth. in solid phase and aging phase, the soluble sugar content of oat seedlings gradually reduced, soluble protein content and activity of antioxidant enzymes (SOD, CAT and POD) showed a trend of first rising then reducing.As the extension of growth period of Cenchrus pauciflorus Benth., the leaching solution made cell membrane permeability of oat seedlings increase gradually, the MDA content and proline content increase, chlorophyll, soluble sugar and soluble protein content reduce gradually. Under low concentration of leaching solution, the activity of antioxidant enzymes in the treatment group of seedling stage Cenchrus pauciflorus Benth. was minimum, the ageing treatment group was maximum; while under high concentration of leaching solution, the activity of antioxidant enzymes in seedling stage Cenchrus pauciflorus Benth. treatment group was maximum, the ageing treatment group was minimum. With the extension of the growth period of Cenchrus pauciflorus Benth., the allelopathic effect that oat seedlings received increased.