【作者】 苏艳丽；

【导师】 赵思东；

【作者基本信息】 中南林业科技大学 ， 森林培育， 2007， 硕士

【摘要】 ‘天皇’梨为从韩国引进的一个优良砂梨品种。本文采用田间试验观测、营养成分分析和石蜡切片解剖等方法,对‘天皇’梨的枝叶果生长发育动态变化过程、果肉的形成和发育、以及年发育周期中叶片和果实内含矿质成分等方面进行了系统的观察研究。主要结果如下：(1)‘天皇’梨的枝稍生长特点为：1年生长枝一般较长,平均为70.29cm,芽发育饱满充实,但花芽率较低,只有34.18%,多位于中上部。树体花朵座果率较高,可达61.67%。短枝、中枝、长枝的总枝数及新梢总长差异非常大。在生长量方面,短枝以结果为主,生长量最少,而长枝的生长量最大,占所有新梢生长量的85.63%。‘天皇’梨的新梢生长分1次生长和2次生长。只有1次生长的新梢增长时间短,最终发育为短枝和中枝,有2次生长的新梢发育时间长,最终发育为长枝。树体叶幕的形成在5月初。新梢与叶片的生长间无相关性。(2)‘天皇’梨的果实生长发育特点为：‘天皇’梨在株洲地区3月底进入盛花期,9月中上旬果实成熟,生长周期为150d至175d。‘天皇’梨纵、横径日增长量有3个生长高峰。第1个生长高峰正是果肉细胞快速分裂期,细胞数目大量增加,细胞较小,各部分细胞大小及形态无明显差异,排列紧密,体积和重量增长缓慢；第2个生长高峰期正是果肉细胞体积迅速膨大期,各部分细胞的体积膨大速度不同,由外向内逐渐增大,果实的体积、重量快速增加；第3个生长高峰时,果肉细胞体积继续膨大,内含物不断积累,果重和品质均达到较佳状态。果实表皮层在发育早期就分布有许多气孔,但很快被皮孔代替,并进而形成果点。果实石细胞的发育较早,在4月12日即有单个石细胞出现,至7月初石细胞团数目基本稳定。胚的发育从4月上旬开始,期间经历了2细胞原胚、棒状原胚、球形原胚等,到6月初,胚已基本成熟,具有完整的胚芽、胚根、胚轴、子叶。(3)‘天皇’梨果实不同的生长发育时期与其体积、重量都呈极显著正相关,与其体积的线性回归方程为Y=-133.499+4.418X,与其重量的线性回归方程为Y=-134.138+4.435X。果实纵、横径与体积间也呈现极显著正相关,三者间的线性回归方程为Y=-155122+7651.395X1-907.398X2(横径为自变量X1,纵径为自变量X2,体积为因变量)。(4)‘天皇’梨叶片中矿质元素的周年变化特点为：叶片中氮、磷、钾、镁的含量都是在幼果期最高,在果实成熟期降至最低。钙的含量则相反,在幼果期最低,在果实成熟期达到最高,氮与钙的变化幅度较大,其它元素变化平缓。到9月下旬果实采收时,叶片中这几中矿质元素含量的顺序为：钙>氮>钾>镁>磷。叶片中钙元素与氮、磷、钾、镁元素都呈极显著负相关,而其它几种矿质元素间均呈极显著正相关。6月底到7月中旬初步确定为‘天皇’梨叶片营养诊断的采样适期。(5)‘天皇’梨果实中矿质元素的周年变化特点为：果实中氮、磷、钾、钙、镁的含量从幼果期到果实成熟期呈现逐渐递减的规律性变化。氮、钾的变化幅度较大,磷、钙、镁的变化平缓。果实成熟时这几种矿质元素含量的顺序为：钾>氮>磷>镁>钙。果实年周期内各矿质元素间都呈极显著正相关。单果中氮、磷、钾、钙、镁这5种矿质元素含量在一定阶段呈逐渐递增的趋势,在幼果期的累积量较小,在果实发育的中后期累积量较大。在整个生长发育期间,单果中钾元素的增长速率一直是正值,而其它的氮、磷、钙、镁元素在果实中都分别出现负增长的情况。花后75 d(6月14日)前后,是‘天皇’梨果实吸收氮、磷、钾、钙、镁这些元素的高峰期。(6)‘天皇’梨叶片和果实的氮、磷、钾、镁元素间存在极显著正相关,钙元素间存在极显著负相关。不同的生长发育时期与叶片中的钙元素呈显著正相关,与果实和叶片中的氮、磷、钾、镁元素都呈显著负相关。叶片和果实中的矿质元素与单果重都呈显著性相关,且叶片中矿质元素与单果重的相关性更好。更多还原

【Abstract】 ’Tianhuang’ pear is a new pear cultivar introduced from Korean.Through field test and observation,component analysis of mineral nutrition,paraffin section anatomise,the paper made a systematic observation and study on the process of ’Tianhuang’ pear shoots, leaves and fruits,formation and development of flesh,contents changes of mineral elements in leaves and fruits in an annual cycle.The main results as follows:(1) The growth fruits of ’tianhuang’ pear shoot were:new long shoot was very long and averaged 70.29cm,bud was filled,but flower bud rate was rather low and had only34.18%, flower bud mostly located in the middle and top of shoot. Fruit setting percentage is 61.67%.The amounts of shoot and the whole length of new shoot among short-shoot,middle-shoot and long-shoot were greatly different. Short shoots which majored in fruiting had minimal growth increments,while long-shoots had maximum growth increments and accounted for 85.63% of the whole growth increments. ’Tianhuang’ pear had two shoot growth types:one-time growth and two-time growth.The former growth duration was more shorter,and formed short and middle shoot finally; The later growth duration was more longer,and formed long shoot finally. The formatoin of leaf curtain was in early May.The correlation between new-shoot and leaf was no significant difference.(2)The growth and development fruits of tianhuang’pear were:’tianhuang’ pear came into full bloom stage in the end of March and the stage of fruit ripening was in early and middle September,and the growth cycle was about 150d to 175d in zhuzhou. The average daily diameter and length accumulated of ’tianhuang’ pear had three growing tops.In first growing top,mesocarp cells rapidly divided and the number of cell increased widely,and cells were more smaller and densely arranged,each several part of cell was no significant difference,volume and weight of fruit increased slowly; In second growing top,volume of flesh cells expanded fastly at different speed.Flesh cells increased gradually from outer to inner. Volume and weight of fruit increased quickly; In third growing top, volume of flesh cells continued to expanded and inner contents accumulated. Weight and quality of fruit were at better state.Fruit sclereids began to develop early.and per sclereid appeared in 12,December,and the number of sclerid group retained stable in early July. Embryo began to develop in early April, and there were six stages during the development of embryo,including two celled proembryo, cdub-like proembryo, globularl proembryo,ect. Mature embryo formed in early June,which had germ,hypocotyl,randicleand cotyledons.(3)The process of ’tianhuang’ pear fruit growth and development and volume and weight of fruit were all significantly positive correlated. Equation of linear regression between the process of fruit growth and volume is Y=-133.499+4.418X, equation of linear regression between the process of fruit growth and weight is Y=-134.138+4.435X. Diameter and length of fruit and volume are significantly positive correlated,their equation of linear regression isY=-155122+7651.395X1-907.398X2(diameter is X1,length is X2, volume isY)(4) Annual changes features of mineral elements in leaves of ’tianhuang’ pear were:Contents of several mineral,including N,P,K,Mg in leaves were the maximum in small fruit stage, and reached the lowest level during ripening stage,while, Contents of Ca was the minimum in small fruit stage, and reached the highest level during ripening stage, N and Ca had larger variation and other minerals kept in a constant level.The sequence of 5 mineral elements contents in leaves was Ca>N>K>Mg>P in late September. There was very significant negative correlation between Ca and N,P,K and Mg in leaves, and there was significantly positive correlation between N,P,K and Mg. The optimal sampling period of leaf analysis was from the end of June to middle July.(5) Annual changes features of mineral elements in fruits of ’tianhuang’ pear were:Contents of N,P,K,Ca,Mg in fruit were gradually decreased from young fruit stage to ripening stage. N and K had larger variation,while P,Ca,Mg kept in a constant level.The sequence of 5 mineral elements contents in fruit was K>N>P>Mg>Ca in ripening stage.There was very significant positive correlation between N,P,K, Ca and Mg during the process of fruit growth. Contents of N,P,K,Ca and Mg in per fruit were gradually increased at certain stage,while their accumulation in small fruit stage were lower than it in middle and later fruit growth.Contents of K in per fruit always increased positively and other four mineral elements had negative increase during the process of fruit growth and development. The top stage of absorbing N,P,K,Ca and Mg in ’tianhuang’ pear fruit was about in 75 days after blossom(14,June).(6)There was very significant positive correlation between N,P,K,Mg in leaves and fruits,while Ca was significantly negative correlated. The process of fruit growth and development and Ca in leaves were significantly positive correlated,and N,P,K,Mg in fruit and leaves were significantly negtive correlated. There was very significant correlation in five mineral elements in leaves and fruits and per fruit weight,the correlation between five mineral elements in leaves and per fruit weight was better.更多还原