假植密度对金萱茶苗生长及生理特性的影响

摘要

Temporary planting of tea seedlings is an important technical measure for enhancing the survival rate of cloning seedlings introduced from the southern area of China.In order to explore the suitable density of tea temporary planting in the environment conditions of Shandong Province,one-year-old cutting seedlings of Camellia sinensis cv.Jinxuan were used as materials,and four planting densities of D1 (1 plant per cluster),D2 (25 plants per cluster),D3 (50 plants per cluster) and CK (100 plants per cluster) were designed for the experiment.The root morphological parameters,root activity,length of young shoots,chlorophyll fluorescence parameters and survival rate before transplanting were studied.The results indicated that:(1) the root zone temperature increased with the increasing of planting density,and it was significantly different among the treatments during dormancy period,while that of D1 was significantly lower compared to CK during germination period.(2) The length,surface area,volume and numbers of new roots were all showed D3 ＞ D2 ＞ CK ＞ D1,but there was no significant difference between D3 and D2.In addition,the new roots of D3 generated earlier and the root activity was significantly higher than the other treatments during dormancy period.D2 had the highest root activity during germination period,and had no significant difference with D1 and D3.(3) D2 had the highest survival rate and the longest length of young shoots.The chlorophyll fluorescence parameters (Fv/Fo,Fv/Fm and qP) of tea seedlings showed D3 ＞ CK ＞ D2 ＞ D1 during dormancy period but D2 ＞ D3 ＞ D1 ＞ CK during germination period.After comprehensive analysis and comparison,D2 treatment seedlings could achieve more suitable root zone temperature,better growth of root,the highest root activity in germination period,rapid growth of new shoots,but suffered less stress of light,moisture and nutrition.All these indicated that D2 was the more suitable temporary planting density for introduced tea seedlings.%茶苗假植是提高山东引种南方无性系良种茶苗成活率的一项重要技术措施.为筛选适宜山东气候条件的茶苗假植密度,以金萱茶树品种一年生扦插苗为试材,设置1株/丛(D1)、25株/丛(D2)、50株/丛(D3)、100株/丛(CK)四种假植密度进行试验,分析了不同处理茶苗的根形态参数、根系活力、新梢长度、叶绿素荧光参数以及移栽前的成活率,结果表明:(1)假植茶苗根区温度随密度增大而升高,在休眠期各处理之间差异显著,而萌芽期仅D1显著低于CK.(2)茶苗新根根长、根表面积、根体积和根系数量均表现为D3＞D2＞ CK＞ D1,但D3、D2间差异不显著.此外,D3发根最早,且在休眠期根系活力显著高于其他处理;D2在萌芽期根系活力最高,但与D1、D3无显著差异.(3)茶苗成活率及新梢长度均以D2最高,叶绿素荧光参数Fv/Fm、Fv/Fo、qP值在休眠期均为D3＞ CK＞ D2＞ D1,在萌芽期却为D2＞D3＞D1 ＞CK.综合分析比较,以D2处理能保持较适宜的根区温度,根系发育较好,萌芽期根系活力最高,新梢生长快,同时光照、水分、营养胁迫较小,是较为适宜的茶苗假植密度.