耿氏假硬草种子萌发条件的研究  

Study on the environmental factors affecting seed germination of Pseudosclerochloa kengiana

作　　者：高海涛 吴希宝 于佳星 张伟 董立尧 

机构地区：[1]南京农业大学植物保护学院/农作物生物灾害综合治理教育部重点实验室,江苏南京210095

出　　处：《南京农业大学学报》2017年第5期835-841,共7页Journal of Nanjing Agricultural University

基　　金：国家公益性行业(农业)科研专项(201303031)

摘　　要：[目的]明确耿氏假硬草(Pseudosclerochloa kengiana)的休眠特性以及温度、光照、pH、水势、盐分和埋土深度对其种子萌发和出苗的影响。[方法]采用培养皿法和盆钵法进行种子萌发和出苗试验,测定萌发率并计算种子萌发指数、种子平均萌发时间等指标。[结果]耿氏假硬草具有1个月以上的休眠期,5 cm土下层积和低温水储有利于种子休眠的解除;种子萌发最适温度为15~20℃;耿氏假硬草萌发过程不需要光照刺激,且不同光照周期对种子萌发没有明显影响;在pH值4~10内均可萌发,且不同pH值之间种子萌发没有显著性差异;对水势不敏感,当水势大于-0.6 MPa时其萌发率才有明显下降;具有较高的耐盐性,当Na Cl达到160 mmol·L-1高浓度时,其萌发率仍高达83%;种子在土表0.5 cm以上时出苗不受影响,当埋种深度大于2 cm时,已基本不能出苗。[结论]确定了耿氏假硬草具有1个月以上的休眠期且土下层积和低温水储可解除种子休眠;同时明确了温度、水势、盐分及埋土深度对种子的萌发具有一定的影响,而光照和pH对种子萌发没有影响。[ Objectives ] The objective of this study is to determine the dormancy characteristics of Pseudosclerochloa kengiana. Experi- ments were conducted to evaluate the effects of temperature, light, pH, osmotic stress, salt stress and seed burial depth on seed germi- nation and seedling emergence of P. kengiana. [ Methods ] Petri dishs and dots were applied to determine seed germination and emergence, including the rate, index and average time of seeds germination. E Results] The mature seeds required more than 1 month of dormancy after collected from fields, however, stratification （ 5 cm underground） and low-temperature water storage could relieve this action.The best temperature range for seed germination was from 15 to 20 ℃ without light stimulation, meanwhile, the different light cycles had no obvious effect on seed germination. More than 80% of seeds germination could be done at pH values from 4 to 10,the rate of germination was not significantly different during different pH values. P. kengiana will be sensitive to water potential and the rate of germantion will be significantly reduced after the water pressure was below 0.6 MPa. It is also resistant to salt stress with 83% rate of seed germination when NaC1 is at the concentration of 160 mmol L-l. There is no effect on germination when the seeds are above 0.5 cm in the soil table, moreover, the emergence will not happen if the depth is more than 2 cm. [ Conclusions ] This study confirmed that the seeds of P. kengiana have more one month dormancy and the dormancy could be relieved by underground and low temperature water. Meanwhile,temperature,water potential,salt and the depth of buried soil affect seed germination with different levels,while the light and pH not.

关 键 词：耿氏假硬草 休眠 种子萌发 环境因子 

分 类 号：S451.2[农业科学—植物保护]