外施脱落酸对不同抗寒性狗牙根品种的渗透调节物质响应研究

以2份抗寒和2份寒敏感盆栽狗牙根为供试材料,在入冬前对其叶面喷施4种浓度(0,5,15,25mg/L)的脱落酸(ABA),经4℃低温处理24,72h,以常温为对照,探讨ABA是否能够提高狗牙根的抗寒性,不同材料适宜的喷施浓度是否一致以及不同抗寒性狗牙根在此过程中的生理响应差异。结果表明,与喷水相比,喷施15mg/LABA可使抗寒狗牙根(新农1号与喀什狗牙根)茎、叶电导率降低,提高了其对低温的适应,而寒敏感狗牙根(普通狗牙根和海岸狗牙根)其适宜的喷施浓度为5～15mg/L ABA;在4个不同浓度的ABA浓度处理中,当ABA浓度为15mg/L时,抗寒的狗牙根电导率基本接近常温对照,MDA含量为最低,脯氨酸、可溶性蛋白含量最高,而寒敏感狗牙根在ABA浓度为5 mg/L时,电导率、MDA含量最低,脯氨酸含量最高,可溶性蛋白含量峰值出现在15mg/L时;在最适喷施浓度下,经低温处理,抗寒与寒敏感狗牙根在脯氨酸积累方面存在差异,抗寒狗牙根与常温对照相比,其脯氨酸含量增加5～8倍,但寒敏感狗牙根仅增加2～3倍。

Studies on Response of Spraying Exogenous ABA to Osmotic Adjustment Substance of Bermudagrass Varieties with Different Cold Resistance

The two portions of Bermudagrass,one of which has cold-resistant and another one of which is susceptible to cold,were used as test materials,whose leaves were sprayed with ABA(0 mg/L,5 mg/L,15 mg/L,30 mg/L) with different concentrations,then were processed at room temperature of 4 ℃ for 24,72 h,as control before the winter in order to discuss whether ABA could improve cold tolerance of Bermudagrass,whether proper spraying concentration of different materials were the same,and whether physilogical reponse difference of different cold-tolerance Bermudagrass existed under the process.The results showed that by comparison with spraying water,and 15 mg/L ABA could decrease electrical conductivity of stem and leaf of cold-resistant Bermudagrass(Cynodon dactylon(L.) Pers cv.Xinnong No.1,Cynodon dactylon(L.) Pers cv.Kashi),and improve adaptability to low temperature,while the proper concentration for cold-sensitive Bermudagrass(common Bermudagrass and coastal Bermudagrass) was 5 15 mg/L ABA.When ABA concentration with four different concentrations was treated and its concentration was 15 mg/L,the electrical conductivity of cold-resistant Bermudagrass are almost same with the check(room temperature),MDA content reaches the lowest,proline and soluble protein content were the highest.While the electrical conductivity and MDA content of cold-sensitive Bermudagrass is the lowest,proine content is the highest when spraying 5 mg/L ABA,soluble protein content reaches 5 mg/L ABA.When the most proper ABA concentration was sprayed,proline accumulation between cold-resistant and cold-sensitive Bermudagrass have differences,when comparing with room temperature control,the content of proline increases by 5-8 times,but the cold-sensitive Bermudagrass increases only by 2-3 times.