Stipagrostis pennata, a typical psammophyte, can resist drought due to the formation of a special rhizosheath. Plant, soil and microbe work together to contribute to the formation of the rhizosheath. Sand sterilization experiments were carried out in the laboratory to investigate the function of soil microbes on seed germination, seedling growth and rhizosheath formation of Stipagrostis pennata. The results showed that: (1) On sterilized sand, seed germination rate was lower when compared to seeds planted on non-sterilized sand (control treatment). With the help of soil microbes, seed germination rate stablized around 25% after 19 d-planting on the non-sterilized sand. (2) Sand sterilization also dramatically reduced the seedling survival rate to near 5%, however, the rate was as high as 36.54% on non-sterilized sand. (3) After 40 d-planting, the seedling plant height on non-sterilized sand was 1.72 times greater when compared to sterilized sand plots. Fresh, light green seedlings were observed on non-sterilized sand while wilting seedlings were found in sterilized plots. (4) Sand sterilization was suggested to impede the formation of rhizosheaths. Sand sterilization visibly weakened the sand adhesion ability of the root. The root hair wilted due to the loss of protection from root and microbe exudate. In conclusion, soil microbes play an important role in seed germination, seedling survival and rhizosheaths formation of Stipagrostis pennata.
[1] 王绍明.古尔班通古特沙漠羽毛针禾(Stipagrostis pennata)种群生态学研究[D].兰州:兰州大学,2005.
[2] 王建明,张霞,王绍明.羽毛针禾萌发特性研究[J].种子,2009,28(5):8-10.
[3] 马大伟,刘彤,赵新俊,等.羽毛针禾种群中尺度的分布格局及利它作用[J].应用与环境生物学报,2010,16(6):753-758.
[4] 邱东,吴楠,张元明,等.根鞘微生境对羽毛针禾沙生适应性的生态调节[J].中国沙漠,2012,32(6):1647-1654.
[5] Wang S M,Zhang X,Li Y,et al.Spatial distribution patterns of the soil seed bank of Stipagrostis pennata (Trin.) de Winter in the Gurbantonggut Desert of north-west China[J].Journal of Arid Environments,2005,63:203-222.
[6] 张玲,王绍明,张霞,等.羽毛针禾种群遗传多样性分析[J].安徽农业科学,2011,39(21):12643-12645.
[7] 朱丽洁,王绍明,夏军,等.羽毛针禾(Stipagrostis pennata)克隆构型及不同环境中的分株种群特征[J].干旱区研究,2012,29:770-775.
[8] Morgan J A W,Bending G D.Biological costs and benefits to plant-microbe interactions in the rhizosphere[J].Journal of Experimental Botany,2005,56(471):1729-1739.
[9] 李春俭,马玮,张福锁.根际对话及其对植物生长的影响[J].植物营养与肥料学报,2008,14(1):178-183.
[10] 潘惠霞,程争鸣,张元明,等.寡营养细菌(Oligographic bacteria)及其固沙作用的研究[J].中国沙漠,2007,27(3):473-477.
[11] Wu N,Zhang Y M.The role of nonphotosynthetic microbes in the recovery of biological soil crusts in the Gurbantunggut Desert,Northwestern China[J].Arid Land Research and Management,2010,24(1):42-56.
[12] Unno Y,Okubo K.Plant growth promotion abilities and microscale bacterial dynamics in the rhizosphere of Lupin analysed by phytate utilization ability[J].Environmental Microbiology,2005,7(3):396-404.
[13] 王茹华,张启发,周宝利,等.浅析植物根分泌物与根际微生物的相互作用关系[J].土壤通报,2007,38(1):167-172.
[14] 贺国强,王磊,邓志平,等.固氮·解磷菌剂对小麦种子萌发及田间小麦产量的影响[J].安徽农业科学,2011,39(7):3875-3876,3888.
[15] 贺慧,燕玲,郑彬.5种荒漠植物种子萌发特性及其吸水特性的研究[J].干旱区资源与环境,2008,38(1):184-188.
[16] Morpeth D R,Hall A M.Microbial enhancement of seed germination in Rosa corymbifera 'Laxa'[J].Seed Science Research,2000,10(4):489-494.
[17] 胡永锋,王雪芹,郭洪旭,等.古尔班通古特沙漠半固定沙垄表面风的脉动特征[J].中国沙漠,2011,31(2):393-399.
[18] 张元明,王雪芹.荒漠地表生物土壤结皮形成与演替特征概述[J].生态学报,2010,30(16):4484-4492.
[19] 钱亦兵,吴兆宁,杨海峰,等.古尔班通古特沙漠纵向沙垄植被空间异质性[J].中国沙漠,2011,31(2):420-427.
[20] 王桔红,崔现亮,陈学林,等.中、旱生植物萌发特性及其与种子大小关系的比较[J].生态学报,2007,31(1):1037-1045.
[21] 李兴华,方子森,牛俊义.胡麻种子形态结构与萌发特性的研究[J].种子,2012,31(11):26-30.
[22] 龙利群,李新荣.微生物结皮对两种一年生植物种子萌发和出苗的影响[J].中国沙漠,2002,22(6):581-585.
[23] 龙利群,李新荣.土壤微生物结皮对两种一年生植物幼苗存活和生长的影响[J].中国沙漠,2003,23(6):656-660.
[24] Darbar S R,Lakzian A.Evaluation of chemical and biological consequences of soil sterilization methods[J].Journal of Environmental Sciences,2007,5(2):87-91.
[25] 刘彩霞,黄为一.耐盐碱细菌与有机物料对盐碱土团聚体形成的影响[J].土壤,2010,42(1):111-116.
[26] 陈文峰.Sinorhizobium meliloti应译为"草木樨中华根瘤菌"[J].中国科技术语,2008,10(3):62-63.
[27] Othman A,Amer W M,Fayez M,et al.Rhizosheath of sinai desert plants is a potential repository for associative diazotrophs[J].Microbiological Research,2004,159(3):285-293.
[28] Bergmann D,Zehfus M.Grass rhizosheath:associated bacterial communities and potential for nitrogen fixation[J].Western North American Naturalist,2009,69(1):105-114.
[29] Young I M.Biophysical interactions at the root-soil interface:a review[J].Journal of Agricultural Science,Cambridge,1998,130:1-7.
[30] Walker T S,Bais H P,Grotewold E,et al.Root exudation and rhizosphere biology[J].Plant Physiology,2003,132:44-51.
[31] 张锡洲,李廷轩,王永东.植物生长环境与根系分泌物的关系[J].土壤通报,2007,38(4):785-789.
[32] Watt M,McCully M E.et al.Plant and bacterial mucilages of the maize rhizosphere:comparison of their soil binding properties and histochemistry in a model system[J].Plant and Soil,1993,151(2):151-165.
[33] 李娜,韩晓增,尤孟阳,等.土壤团聚体与微生物相互作用研究[J].生态环境学报,2013,22(9):1625-1632.
[34] 冯固,张玉凤,李晓林.丛枝菌根真菌的外生菌丝对土壤水稳性团聚体形成的影响[J].水土保持学报,2001,15(4):99-102.
[35] 谢越,杨高文,周翰书,等.丛枝菌根真菌研究中土壤灭菌方法综述[J].草业科学,2012,29(5):724-732.
