【作者】 赵江宁；

【导师】 王余龙；

【作者基本信息】 扬州大学 ， 生态学， 2008， 硕士

【摘要】 铜(Cu)是植物生长所必需的元素,但土壤Cu浓度过高会给植物生长造成伤害。一般认为,清洁土壤(一级农田)的Cu浓度为35 mg·kg-1,轻污染土壤(二级农田)的Cu浓度为100 mg·kg-1,重污染土壤(三级农田)的Cu浓度为400 mg·kg-1。随着现代工业的迅速发展和含Cu农药的大量使用,Cu污染土壤的面积逐年扩大。为了明确土壤Cu污染对群体条件下水稻生长发育的影响,本研究设土壤Cu浓度为一级农田(CK,Cu浓度为30.13 mg·kg-1土)、200 mg·kg-1和400 mg·kg-1 (三级农田)3个水平,研究其对4个籼稻品种生长发育及其产量形成的影响,以期为土壤Cu污染地区的水稻栽培和品种选择提供依据。主要结果如下:(1)土壤铜处理使4个籼稻品种不同生育时期根系、茎鞘、叶片和穗的铜浓度均极显著提高,品种间差异显著。土壤铜处理对不同生育时期根系铜浓度的提高幅度差异不大,对茎鞘和叶片铜浓度的提高幅度为分蘖期>抽穗期>成熟期,对穗部铜浓度的提高幅度为抽穗期>成熟期。品种与铜处理对分蘖期根系、茎鞘和叶片铜浓度以及对抽穗期穗部铜浓度的影响有显著性互作效应。(2)土壤铜处理使4个籼稻品种分蘖期和抽穗期地上部诸器官与根系铜浓度的百分比均大幅度下降。分蘖期叶片铜浓度与根系铜浓度的百分比品种间有显著差异,分蘖期茎鞘铜浓度与根系铜浓度的百分比以及抽穗期地上部诸器官铜浓度与根系铜浓度的百分比品种间无显著差异。品种×铜处理对不同生育时期地上部器官铜浓度与根系铜浓度百分比的影响均无互作效应。(3)土壤铜处理使4个籼稻品种的生育期日数明显增加,使分蘖期、抽穗期的叶面积指数显著变小。土壤铜处理使水稻生育初期的主茎出叶速度明显变慢、功能叶叶色明显变淡、株高明显变矮、分蘖数明显减少,对主茎叶片数和功能叶叶色影响的时期分别为移栽后28和21天之内,对株高和茎蘖数的影响的时期为移栽后28天之内,且土壤铜处理浓度越高,影响程度越大。土壤铜处理对水稻生育中、后期的主茎出叶速度、功能叶叶色、株高、分蘖发生影响不大。(4)土壤铜处理极显著降低了4个籼稻品种分蘖期、抽穗期的单株不定根总数、不定根总长度、单株根系总干重和分蘖期不定根平均长度及单株α-萘胺氧化力,极显著增加了水稻抽穗期不定根根粗,但对抽穗期每条不定根平均长度和分蘖期单位干重α-萘胺氧化力无显著影响。分蘖期和抽穗期的单株不定根总数、单株根系干重、单位干重α-萘胺氧化力,抽穗期不定根根粗、每株不定根总长度和单株α-萘胺氧化力的品种间差异达极显著水平。品种×铜处理对水稻抽穗期根系总干重有极显著互作效应,对分蘖期与抽穗期单株不定根总数、每株不定根总长度、每条不定根平均长度、不定根根粗、单位干重α-萘胺氧化力、单株α-萘胺氧化力以及分蘖期根干重的影响无显著互作效应。(5)200 mg·kg-1、400 mg·kg-1土壤铜处理使4个籼稻品种分蘖期的干物重均极显著降低,且铜处理浓度越高降低幅度越大。200 mg·kg-1土壤铜处理对4个籼稻品种抽穗期和成熟期的干物重影响不大,但400 mg·kg-1土壤铜处理使4个籼稻品种抽穗期和成熟期的干物重极显著降低(下降幅度明显小于分蘖期)。土壤铜处理对于不同生育时期干物质在不同器官中的分配几乎没有影响(除了200 mg·kg-1处理降低了成熟期穗部比例之外)。(6)土壤铜处理极显著地降低了4个供试籼稻品种的产量,且铜处理浓度越高,产量降低幅度越大。土壤铜处理对水稻产量构成因素中每穗颖花数和千粒重的影响较大,达到极显著水平,对单位面积穗数和结实率的影响未达到显著水平。单位面积产量、单位面积穗数、每穗颖花数、结实率和千粒重品种间的差异均达到极显著水平。品种×铜处理对单位面积穗数、每穗颖花数和千粒重有显著性互作效应。更多还原

【Abstract】 Copper (Cu) is an essential element for plants, but the excessive soil Cu could have adverse effects on plant growth. According to soil quality assessment, the Cu concentration of the clean soil (first class farmland) was 35 mg·kg-1, light polluted soil (second class farmland) was 100 mg·kg-1, and heavy polluted soil (third class farmland) was 400 mg·kg-1. With the rapid development of industry and large-scaled using of herbicides and pesticides which contains Cu, the area of soil contaminated by Cu expanded every year. In order to clarify the effect of soil copper contamination on growth and development of rice, a soil culture experiment was conducted using 4 indica rice cultivars with 3 levels of soil Cu treatment(CK, none Cu addition, 30.13 mg·kg-1; 200 mg·kg-1; 400 mg·kg-1)under mimic-field conditions. Main results are as follows:(1) Soil Cu treatments significantly increased the Cu concentrations in roots, stem-sheaths, leaves and panicles of all test varieties at tillering, heading and maturity stages; but different varieties responded differently. There were little differences on the increase of root Cu concentrations between growth stages, but the stem-sheath concentration was increased more at tillering compared with heading and maturity stages; likely, panicle Cu concentration at heading was increased more than that at maturity stage. Significant interactive effects between varieties and Cu treatments were detected on the Cu concentration of roots, stem-sheaths and leafs at tillering stage, and on the panicle Cu concentration at heading stage.(2) At tillering and heading stages, the soil Cu treatments greatly decreased the ratio of Cu concentration of aerial parts (leaf, stem, and panicle) to the roots (RCAR) of all varieties. However, there were no significant differences on RCAR except the ratio of leaves to roots at tillering stages between varieties. At heading stage, no significant differences on all RCARs were detected between varieties. There was no significant interactive effect on RCAR between varieties and Cu treatments at different growth stages.(3) Soil Cu treatments significantly prolonged the growth period, decreased leaf area index (LAI) of four varieties at tillering and heading stages. Soil Cu treatments also greatly slowed down the speed of leave emergence of main stems, reduced the plant height and tillers number. The effects of soil Cu treatment on leaf emergence rate, the plant height and tiller number were disappeared 28 days after transplanting (DAT). Soil Cu treatments caused interveinal chlorosis symptoms on the functional leaves, but the effects were apparent only before 21 DAT. The impact of 400 mg·kg-1Cu treatment was greater than that of 200 mg·kg-1. In the middle and late growth stages, there were little effects of higher soil Cu concentration on the leaf emergence rate, functional leave color, plant height and total tiller number.(4) Soil Cu treatments significantly reduced the number and total length of adventitious roots per-plant, significantly decreased the dry weight of roots per-plant at tillering and heading stages, reduced the average length of adventitious roots andα-naphthylamine (α-NA) oxidizing capacity per-plant at tillering stage, significantly increased the diameter of adventitious root at heading stage; Soil Cu treatments affected little on the average length of adventitious root at heading stage andα-NA oxidizing capacity at tillering stage based on dry weight. There were significant differences between varieties on the number of adventitious roots per-plant, the root dry weight per-plant,α-NA oxidizing capacity per-gram dry weight at tillering and heading stages, as well as the diameter of adventitious root, total length of adventitious roots per-plant andα-NA oxidizing capacity per-plant at heading stage. Significant interactive effects between varieties and Cu treatments were detected on the root dry weight at heading stage, but no effect was detected on number and total length of adventitious roots per-plant, the average length of adventitious roots, the diameter of adventitious root,α-NA oxidizing per-weight,α-NA oxidizing per-plant at tillering and heading stages, and the plant root dry weight at tillering stage.(5) Both 200 mg·kg-1and 400 mg·kg-1 soil Cu treatments significantly reduced the dry weight at tillering stage of all tested varieties, and the higher the concentration, the greater the reduction. As to heading and maturity stages, 200 mg·kg-1 soil Cu treatment had no effects on dry weight of all tested varieties, while 400 mg·kg-1 had significant negative effects on dry weight (But the negetive effect was smaller than that at tillering stage). Soil Cu treatment had no effect on the dry matter distribution of different organs at all growth stages, except that the 200 mg·kg-1 treatment reduced the proportion of dry matter in panicles at harvest.(6) Soil Cu treatments significantly reduced the grain yield of all varieties, and the higher the concentration, the greater the yield decreased. There were significant differences on spikelet number per panicle and 1000-grain weight with different soil Cu treatments, while no effect was detected on the panicle number per area and filled grain percentage. There were significant differences between varieties of gain yield per area, panicle number per area, the spikelet number per panicle, seed setting rate and 1000-grain weight. There was significant interactive effect between varieties and Cu treatments on panicle number per area, the spikelet number per panicle and 1000-grain weight.更多还原