【作者】 房锋；

【导师】 张朝贤； 魏守辉；

【作者基本信息】 中国农业科学院 ， 杂草科学， 2012， 博士

【摘要】 节节麦（Aegilops tauschii Coss.）又名粗山羊草，属禾本科（Gramineae）山羊草属（Aegilops），一年生或越年生世界性恶性杂草，在我国为进境植物检疫潜在危险性杂草之一。山羊草属是小麦野生近缘植物中与小麦亲缘关系最近的一个属。节节麦形态和生长周期与小麦极为相似，能与小麦竞争水分、光、养料和空间等，严重影响小麦的产量和品质。近年来，节节麦在我国河北、山西、山东、河南和陕西等省麦田严重发生，其危害面积已达33万ha，危害程度越来越重，并呈迅速蔓延之势，已成为我国北方麦田恶性杂草。杂草生物生态学研究是杂草治理系统的基础，本研究以麦田节节麦为主要研究对象，2009年²012年，在河北永年、山东肥城和河南新乡研究了节节麦的生态适应性；节节麦与小麦的竞争关系和对小麦产量的影响；运用生物适生性模型并结合地理信息系统（GIS）预测了节节麦在中国的适生区。主要结论如下：（1）明确了光照、温度、水分、pH值、盐分以及埋藏深度等环境因子对节节麦萌发及出苗的影响。每天14h光照培养条件下，节节麦种子的发芽温度范围为5³5℃，最佳发芽温度范围为15²5℃。光照对节节麦萌发没有显著影响。节节麦种子的萌发对酸碱度有较强的适应性，pH在3.0¹0.0环境条件下萌发率均超过92%。节节麦萌发能够耐低水分渗透势，耐盐性。种子最佳出苗深度为1³cm，大于9cm则不能出苗。（2）节节麦的出苗、分蘖动态，株高和鲜重变化与温度密切相关。节节麦的第一个出苗高峰出现在10月下旬¹1月上旬，周平均气温在16.2¹1.6℃之间，约占出苗总量的75%⁸7%；第二个出苗高峰为翌年3月下旬⁴月上旬，周平均气温回升至10℃左右，约占出苗总量的13%²5%。在小麦播后30³5d（11月中旬左右），节节麦和小麦同时进入冬前分蘖期，且形成冬前分蘖高峰。（3）节节麦人工防除经济阈值为5.71株·m^-2，使用3%世玛油悬浮剂化学防除的经济阈值为2.35株·m-2。（4）不同施肥方式对节节麦和小麦生长均有显著影响，当肥料深施于土壤并且靠近小麦种子时，节节麦对小麦生长影响较小；当肥料撒施于土表时，节节麦幼苗比小麦幼苗更易于吸收营养；当肥料靠近小麦播种行深施土表以下时，可以减少节节麦对肥料的吸收并且促进小麦对肥料的吸收。在无节节麦影响下，土表撒施、条带式深施和穴施三种施肥方式和不施肥对照相比，分别使小麦增产18.0、25.5和24.7%；在有节节麦（50穗/m²）影响下，土表撒施、条带式深施和穴施三种施肥方式和不施肥对照相比，分别使小麦增产8.1、22.0和25.3%。（5）我国陕西、山西、山东、河北、河南和江苏六省区麦田的节节麦之间遗传相似系数（GS）多为0.9左右，亲缘关系较近，遗传分化较小，遗传聚类关系与材料的地理来源相关。（6）节节麦在全球适生区主要分布于北纬30⁴5°之间，西亚、中东、欧洲东南部和非洲北部地中海沿岸是节节麦在全球的主要适生区；节节麦在我国的适生区主要分布在冬小麦主产区河南、河北、山东、山西西南部、陕西关中平原、宁夏中南部、甘肃东南部、湖北、江苏和安徽北部。随着全球气候的变化，温室气体在A1b排放情景下，到2050年，节节麦在全球适生范围将有扩大趋势；A2a和B2a排放情景下，节节麦低适生区和中适生区则有缩减趋势，但高适生区变化不明显。更多还原

【Abstract】 Tausch’s goatgrass (Aegilops tauschii Coss.), an annual or perennial grass weed, is classified asAegilops. Tausch’s goatgrass is an invasive alien species and is a close relative to the wheat (Triticumaestivum). The morphology and growth cycle is very similar to wheat, Tausch’s goatgrass competes withwheat for water, light, nutrients and space, is a serious issue on wheat yield and quality. In recent years,an estimated330,000ha are infested in winter wheat fields in Hebei, Shanxi, Shandong, Henan, andShaanxi provinces. Increasing damage and rapid spreading made it a serious weed species in winterwheat fields.Weed biology and ecology are the basis of the weed management systems, Studies were conductedto determine the adaptability of Tausch’s goatgrass in winter wheat fields, competitive relationship withwheat, impacts on the yield of wheat, and the potential distribution in China and the world from2009to2012. The main conclusions are as follows:1. The effects of environmental factors affecting seed germination and seedling emergence wereevaluated in laboratory and greenhouse experiments. The germination of Tausch’s goatgrass seedsoccurred at temperatures ranging from5to35℃, with optimum germination attained between15and25℃. Tausch’s goatgrass seed is rather tolerant to low water potential and high salinity stress.Medium pH and light have no significant effect on seed germination. Highest emergence (>80%)occurred from depths of1to3cm, but no seedlings emerged when burial depth reached9cm.2. Tausch’s goatgrass emergence, tillering dynamics, height and fresh weight changes were closelyrelated to temperature. Tausch’s goatgrass has two main seedling emergence peaks, one in earlywinter from late October to early November (the weekly average temperature of16.2~11.6℃),about75~87%emerged, and the other in later spring from late March to early April (the weeklyaverage temperature rose to about10℃), about13~25%emerged. Tausch’s goatgrass tilleringability is stronger than wheat.30~35d (about mid-November) after the sowing of the wheat,Tausch’s goatgrass and wheat tillered at the same time, and formed the tiller peak.3. Based on the economic infestation level of A. tauschii and the obtained logarithmic model, theeconomic threshold of A. tauschii was5.71plants·m-2for manual control and was2.35plants·m-2for chemical control by3%Mesosulfuron OF.4. The study indicate that the placement of fertilizer had a significant effect on the growth anddevelopment of both Tausch’s goatgrass and winter wheat. Tausch’s goatgrass competition withwinter wheat was reduced when fertilizer was placed deep in the soil closer to the wheat seeds,however, when fertilizer was broadcast, Tausch’s goatgrass competition with winter wheat waseither enhanced or stayed the same compared to the nonfertilized infested check. It appears thatwith broadcast application, Tausch’s goatgrass seedlings had easy access to fertilizer, compared towheat seedlings. Placing fertilizer deep in the soil and closer to the wheat seedlings reduced the access of Tausch’s goatgrass to nutrients and favored wheat seedlings. In the absence of Tausch’sgoatgrass, broadcast, deep band, and deep spot fertilizer applications increased wheat yield18.0,25.5, and24.7%, respectively, when compared to the weed-free, nonfertilized check. In thepresence of Tausch’s goatgrass, wheat yields were increased8.1,22.0, and25.3%with broadcast,deep band, and deep spot placement, respectively.5. The genetic similarity coefficient (GS) in the six provinces of Shaanxi, Shanxi, Shandong, Hebei,Henan, and Jiangsu is most greater than0.9. Their relationship is close, little genetic differences.The genetic clustering and the geographical origin of the materials have some correlation.6. The global potential distribution area of Tausch’s goatgrass is mainly between30and45°degreesnorth latitude. West Asia, Mid-east, the Mediterranean coast of south-eastern Europe and northernAfrica are the main suitable areas for Tausch’s goatgrass. In China the suitable areas for Tausch’sgoatgrass are mainly distributed in Henan, Hebei, Shandong, southwest of Shanxi, Guanzhong Plainof Shaanxi, the central and south of Ningxia, southeast of Gansu, north of Hubei, Jiangsu and Anhuiprovinces. As the global climate change, the potential distribution range of Tausch’s goatgrass willvary according to different emissions scenarios. With greenhouse gases under the A1b emissionsscenario, by2050, the potential distribution of Tausch’s goatgrass will have a tendency to expand.While under A2a and B2a emissions scenarios, the low-and medium-risk areas will tend todecrease, but the high-risk areas will not change significantly.更多还原