亚低温与干旱胁迫对番茄幼苗根系形态及叶片结构的影响  

Effects of sub-low temperature and drought stress on root morphology and leaf structure of tomato seedlings

作　　者：孙三杰[1] 李建明[1] 宗建伟[2] 姚勇哲[1] 陈凯利[1] 

机构地区：[1]西北农林科技大学园艺学院,陕西杨凌712100 [2]西北农林科技大学林学院,陕西杨凌712100

出　　处：《应用生态学报》2012年第11期3027-3032,共6页Chinese Journal of Applied Ecology

基　　金："十二五"国家科技支撑计划项目(2011BAD12B03)资助

摘　　要：采用WinRhizo2005a根系扫描测定系统和石蜡切片法,研究亚低温(8～15℃)和轻度干旱(正常田间持水量的55%～70%)胁迫对番茄幼苗根系形态及叶片结构的影响.结果表明:亚低温和轻度干旱单一胁迫促进了番茄幼苗根系长度、表面积和体积的增加,而二者交互胁迫导致番茄根系各指标下降;亚低温和轻度干旱单一胁迫下番茄幼苗通过增加0.50～1.00mm径级比例来促进根系长度的增加,通过增加1.00～2.00mm径级比例来增加根系表面积和体积,交互胁迫下番茄幼苗通过减少0.20～0.50mm和<0.20mm2个径级的比例来延缓根系生长.叶片组织结构疏松度(SR)与组织结构紧密度(CTR)呈显著负相关,CTR与栅海比呈显著正相关;亚低温处理下栅栏组织厚度减小,轻度干旱胁迫下栅栏组织和海绵组织厚度均减小,交互胁迫使叶片变薄,栅海比显著降低.By using WinRhizo 2005a root scanning measurement system and traditional paraffin sec- tioning method, this paper studied the root morphology and leaf structure of tomato seedlings under effects of sub-low temperature （8-15 ℃ ） and mild drought stress （55% -70% of normal field ca- pacity）. Single treatment of sub-low temperature or mild drought stress promoted the increase of the seedling root length, surface area, and volume, while the interaction of the sub-low temperature and mild drought stress resulted in the decline of the indices. At sub-low temperature or under mild drought stress, the root length increase was promoted via the increase of the proportion of 0.50- 1.00 mm diameter class roots, and the increase of the root surface area and volume was promoted via the increase of the proportion of 1.00-2.00 mm diameter class roots. Under the interaction of the sub-low temperature and mild drought stress, the root growth was inhibited owing to the decrease of the proportions of 0.20-0.50 mm and 〈0.20 mm diameter classes roots. There was a significant negative correlation between the cell tense ratio （CTR） and spongy ratio （SR）, and a significant positive correlation between the CTR and palisade tissue thickness/spongy tissue thickness. At sub- low temperature, the palisade tissue thickness decreased; under mild drought stress, both the pali- sade tissue thickness and the spongy tissue thickness decreased; whereas the interaction of sub-low temperature and mild drought stress made leaf become thinner and palisade tissue thickness/spongy tissue thickness had a significant decrease.

关 键 词：番茄 根系 亚低温 干旱胁迫栅栏组织 海绵组织 

分 类 号：S641.2[农业科学—蔬菜学]