【摘要】 为探明保水剂对狗牙根(Cynodon dactylon)匍匐茎萌发、幼苗形态特征的影响以及最佳使用量,采用室内盆栽试验,研究了两种水分条件下(足量供水与限量供水)5个梯度的保水剂浓度[0(对照)、 0.10%、 0.20%、 0.30%、0.40%]对狗牙根匍匐茎萌发及幼苗形态的影响,同时利用抗旱性综合评定法对狗牙根抗旱性能进行综合分析与评价。结果表明,1)施加适宜保水剂可以提高狗牙根匍匐茎发芽率、发芽势与发芽指数,足量供水条件下最优保水剂浓度分别为0.30%、0.20%和0.10%,分别较对照提高了13.24%、10.11%与20.14%;限量供水条件下最优保水剂浓度均为0.30%,分别较对照提高了12.67%、14.87%和8.71%。2)施加保水剂可以提升狗牙根幼苗生物量及根冠比,而保水剂浓度在0.20%～0.30%处理时狗牙根幼苗根冠比低于对照。足量供水条件下,根冠比在0.10%处理达到最大值(0.019),限量供水条件下仅0.40%处理(0.013)高于对照。3)施加保水剂能增加狗牙根株高与根系长度,株高在两种水分条件下随保水剂浓度增加呈现为先增加后下降趋势;根系长度在两种水分条件下随保水剂浓度增加而增加,均在0.40%处理达到最大值。4)隶属函数分析结果显示,添加适宜保水剂可以提高狗牙根幼苗抗旱性,5种保水剂浓度下狗牙根幼苗抗旱性顺序在足量供水条件下表现为0.20%> 0.30%> 0.40%> 0.10%> 0,限量供水条件下表现为0.30%>0.40%> 0.20%> 0.10%> 0。因此,在采用狗牙根进行草坪铺设和生态绿化时建议加入浓度0.20%～0.30%的保水剂,有利于绿地建植以及延长草坪灌溉时间。更多还原

【Abstract】 This study was conducted to determine the effect of a super absorbent polymer on stolon germination and seedling morphological characteristics of Cynodon dactylon and optimum polymer quantity.We used an indoor pot experiment with 5 gradients of super absorbent polymer concentration [0(CK),0.10%,0.20%,0.30%,and 0.40%] under two moisture conditions(adequate water supply and limited water supply) to conduct a comprehensive analysis,as well as an evaluation of drought-resistance of C.dactylon.The results showed that:1) A suitable concentration of super absorbent polymer can improve germination rate,germination potential,and the germination index of C.dactylon stolons,and the optimal super absorbent polymer concentration under sufficient water supply conditions was 0.30%,0.20%,and 0.10%,respectively.These values increased by 13.24%,10.11%,and 20.14% compared with that of the CK,respectively.Optimal super absorbent polymer was 0.30% under limited water supply conditions,and the values increased by 12.67%,14.87%,and 8.71%compared with that of the CK,respectively;2) The application of super absorbent polymer improved the biomass and rootshoot ratio of C.dactylon seedlings,whereas when the concentration was 0.20% to 0.30%,the C.dactylon root-shoot ratio was lower than that of the CK.Under sufficient water supply conditions,root-shoot ratio reached the maximum(0.019) at0.10%,and at 0.40%(0.013) under the limited water condition,the root-shoot ratio was higher than that of the CK;3) The application of super absorbent polymer could increase the plant height and root length;plant height increased first and then decreased with the increase of super absorbent polymer concentration under the two water conditions.Root length increased with the increase of super absorbent polymer concentration under both conditions and reached the maximum in the 0.40%treatment;4) Based on membership function analysis,adding a suitable concentration of super absorbent polymer can improve the drought-resistance of C.dactylon seedlings.The order of concentrations for drought resistance of C.dactylon seedlings was 0.20%>0.30%>0.40%>0.10%>0 under sufficient water supply conditions and was 0.30%>0.40%>0.20%>0.10%>0 under limited water conditions.Therefore,we suggest the addition of super absorbent polymer at a concentration of 0.20%～0.30% when using C.dactylon for lawn laying and ecological afforestation,which is beneficial to greenland construction and prolongation of lawn irrigation time.更多还原