【作者】 贺军虎；

【导师】 王永熙；

【作者基本信息】 西北农林科技大学 ， 果树学， 2003， 硕士

【摘要】 柿树(Diospyros. Kaki Linn)原产于我国长江流域，经过千百年的栽培训化，现在在我国北方广为栽培。渭北早区土层深厚，年降雨量500-600mm，柿树在该区生长结果良好，已成为当地主要果树之一。本研究的目的就是要探讨柿树在渭北旱区干旱条件下的生理适应机制，为柿树的栽培提供理论借鉴。 试验主要研究渭北旱区柿树品种火柿、水柿、木洼柿及柿属君迁子的叶的解剖结构的观察及它们的光合作用和相关因子的变化，并和渭北旱区生长的红富士苹果树、砀山酥梨树作以比较；并研究了盆栽幼龄柿树品种火柿、水柿、次朗柿和柿属君迁子的水分胁迫下光合特性及其SOD、CAT、MDA含量的变化。结果表明：柿树对干旱具有一定的适应性。君迁子的气孔小而且密度小，而栽培品种气孔大而且密度大；火柿、水柿、木洼柿和君迁子的气孔开度日变化为中午降低型；渭北旱区柿树春季叶的栅栏组织发达，栅栏组织与海绵组织的厚度之比较秋叶大，日蒸腾量与二者之比呈负相关；渭北旱区多年生柿树的光合速率、蒸腾速率、及气孔导度的日变化呈“中午降低型”变化，光合作用的降低是气孔和非气孔因素共同作用的，气孔导度与净光合速率呈正相关，叶温与净光合速率呈负相关。光合作用这种变化是柿树经历水分胁迫后对环境的一种适应调节。水分胁迫下，随土壤相对含水量(SRWC)的降低、柿树叶片相对含水量和叶绿素含量降低，火柿、水柿的净光和速率在土壤相对含水量下降初期有所升高，此后随水分胁迫的加剧而下降；次郎柿和君迁子的光合速率随SRWC的降低而下降。水分胁迫下，水柿、君迁子的光合速率的下降在前期主要是由于气孔因素作用，后期是由非气孔因素起主要作用的；而火柿、次郎柿在整个水分胁迫过程中均存在非气孔因素的作用。水分胁迫的初期，随SRWC的降低SOD和CAT酶活性增强，MDA含量下降，表明柿树清除活性氧的能力较强；水分胁迫后期SOD、CAT的活性下降，火柿、水柿和次郎柿的MDA含量上升，而君迁子的MDA含量降低，说明君迁子具有极强的清除活性氧的能力，这是以君迁子为砧木的柿树品种耐旱的生理基础之一。柿树在渭北旱区的生长结果良好，是其对渭北旱区生态环境逐渐适应的结果。更多还原

【Abstract】 Persimmon (Diospyros.kakiLinn) origined from changjiang river areas of china. It has been cultivated widely in the North china after hundreds of years training. WeiBei drought area has profound soil, It has 500-600mm rainfalls a year, persimmon not only existed but also became one of main fruit trees in that area. The aid of this research is to discover How the persimmon adapted to the area on physiology, and to provid theory availability for persimmon cultivating .the test has researched "Huoshi" , "shuishi", "Muwashi" and " Junqianzi" in WeiBei area from the leaves of phyllan thus emblica,the variation of photosynthesis and relative factor, compared with apple tree, pear tree in WeiBei area, and researched young persimmon trees photosynthetic characteristics and SOD, CAT, MDA contens changes under water stress, the result showes:persimmon has adapted WeiBei drought enviroment. The stoma of Junqian zi was small and lesser density, the others were big and density, all of it stomal daily variation was measured as a noon decreasing type, the ratio between palisade and spongy tissue of the spring leaves of persimmon negative correlation with Tr, and daily variation of Pn, Tr and Gs of WeiBei persimmon showed a noon decreasing types, the decreasing of Pn were affected by stomatal and nonstomatal factors, the leaves temperature had negative correlation with Pn, Gs had positive correlation with Pn, under water strees, with SRWC declined, LRWC of persimmon and content of chl were decreasing also, the Pn of " houshi", "shuishi" had a few ascended at beginning, but decreased with SRWC dedine at late stress, Both " shuishi" and "Junqian zi " were affected by stomal factor at early water stress mainly and by nonstomatal limitation at late stress, But Pn of "huoshi" and "cilangshi" were affected by nonstomatal factor all stress, the activity of SOD , CAT were increasing at early water stress, and the content of MDA was decline, but activity of SOD, CAT declined at late water stress, and the contents of MDA of "huoshi", "shuishi" and "cilangshi" were incline, but "Junqianzi" was decline. In showed "Junqian zi" had highest ability to clean activated oxygen , This is one of the drought resistance physiology bases of the persimmon with "Junqian zi" rootstock, persimmon growing well in WeiBei drought area, It is a result that persimmon adaptive to WeiBei ecosystem environment.更多还原