福建山区生境黄花倒水莲生殖构件表型可塑性及变化规律

为了解黄花倒水莲生殖构件表型可塑性及变化规律,在福建山区竹林群落内,采用大样本随机取样,对黄花倒水莲种群的生殖构件进行了表型可塑性的研究。结果表明,在籽实完熟期,黄花倒水莲的单个生殖植株的生物量(58.67±35.77) g;豆荚生物量及豆荚数分别为(6.64±4.93) g、(35.6±30.50)个;种子生物量与种子数分别为(2.61±2.19) g、(61.97±54.15)粒;生殖分配Ⅰ与生殖分配Ⅱ分别为10.55%±3.39%、3.93%±1.62%;各生殖构件表型观测最大值与最小值比值为4.23~39.5。豆荚生物量及豆荚数、种子生物量与种子数与总生物量间呈极显著性的线性正相关关系;豆荚数、种子数、生殖分配Ⅰ与生殖分配Ⅱ与其他组分生物量分配呈极显著性幂函数负相关关系。黄花倒水莲种群生殖植株同时具有同速生长和异速生长2种不同增减过程的表型可塑性调节。     

石羊河流域沙地6种一年生植物的种子特征

对分布在石羊河流域民勤和古浪两县沙区沙地上的6种一年生植物的种子(或果实)外观形态特征、大小、千粒质量、萌发等特性进行了观察和分析研究。结果表明:沙米、沙芥、碟果虫实、雾冰藜、盐生草和小画眉草6种一年生植物的籽实体外观形态特征差异较大,在种子的大小、千粒质量、萌发率等特性上也有较大差异;6种植物种子特性表现出的共同趋势是,种子越小,千粒质量越小,种子均匀性越好,反之,则均匀性越差;常温下沙米种子的萌发率很低,沙芥、碟果虫实和小画眉草种子萌发率较低,但是雾冰藜和盐生草种子萌发率极高,一年生植物种子的萌发机制差异较大。     

流动沙丘先锋植物沙米的种子特征研究

以不同生态区域和不同年份沙米种子为试验材料。研究了沙米种子的形态特征、含水率、千粒重及其萌发特性。结果表明:沙米种子扁平,圆形或半圆形,长径为1.44～3.03mm,短径为1.0～2.19 mm,长短径比为1.0～1.76;常温保存种子含水率为7.08%～13.67%,千粒重介于1.05～1.65 g;沙米种子发芽率低,其萌发需要黑暗条件,属于厌光型种子。沙米种子长径、短径及长短径比、含水率、千粒重和发芽率在不同生态区域或不同年份间总体差异显著。     

松嫩平原蒺藜草(Cenchrus incertus)种群构件生物量分配

通过对松嫩平原蒺藜草(Cenchrus incertus)单优群落植株的取样调查,对其构件的生物量结构、生物量分配进行了定量分析。结果表明:蒺藜草种群籽粒成熟期各构件生物量大小为叶茎花序根,其变异系数分别为167.51%、173.79%、207.37%和125.79%,具有较大的表型可塑性;蒺藜草各构件生物量分配比例大小关系表现为叶茎根花序。蒺藜草植株大小随着根、茎、叶及花生物量的增加呈直线函数形式增加,花生物量分配与总生物量呈显著的正相关性,其余构件生物量分配均与总生物量呈负相关性。     

4个紫花苜蓿品种生物量与植株构件的相关性研究

以Victoria、WL 363 HQ、WL 903、WL 525 HQ 4个品种为试验材料,研究了不同紫花苜蓿品种的构件生物量.结果表明:1)品种WL 525 HQ的生物量相对最大.各品种均把较多的生物量(50以上)分配到根上,分配到花的生物量极少(不到1),品种WL 903分配到花的生物量相对其他品种较高.2)繁殖构件生物量与营养构件生物量之间的相关性未表现出一定的规律.3)幂函数反映了茎、叶生物量随个体地上生物量呈等速生长模式,根、花生物量随个体地上生物量呈异速生长模式.根的生长速率,品种排序为:WL 903＞WL 525 HQ＞Victoria＞WL 363 HQ;花的生长速率,品种排序为:WL 903＞Victoria＞WL 525 HQ＞WL 363 HQ.4)线性函数是植株生物量与构件生物量关系的最佳拟合模型.     

雨久花种群开花期生殖株构件表型可塑性及生长分析

采用大样本取样野外实地测定方法,对丹东地区雨久花种群生殖株的数量性状和生殖分配规律进行了分析。结果表明,在开花期,雨久花种群单个生殖株植株高度和花序长分别为(91.59±7.96)cm和(11.10±2.46)cm,花数为(68.47±18.52)个;生殖株生物量、根生物量、茎生物量、叶生物量和花序生物量分别为(9.97±4.13)g、(1.21±0.66)g、(6.36±2.91)g、(1.35±0.76)g和(1.05±0.51)g。花期雨久花种群生殖株变异系数以叶生物量最大,为56.41%;其次为根生物量54.14%;株高最小,为4.87%,各数量性状具有较大的表型可塑性。雨久花种群生殖株表型可塑性遵循着规律性,即随着株高的增加,花序长和花数量呈幂函数增加,根生物量和花序生物量呈直线增加;花序生物量与总生物量之间不存在相关的函数关系。     

沙生经济植物沙米出苗土壤水分阈值研究

出苗是植物成苗的最重要阶段,明确沙米出苗的土壤水分阈值,对促进野生沙米种群发展和推进沙米人工种植具有重要意义。本文通过设置温度、播种时间、土壤含水率梯度盆栽控制试验,研究沙米不同条件下的出苗率变化,以确定沙米在风沙土出苗的适宜土壤水分含量。结果表明：（1）室内3个不同温度梯度、供试风沙土播前掺水（或播后喷水）的沙米出苗水分阈值下限分别为10.81% (10.0 mm)、10.81% (7.5 mm)和8.51% (7.5 mm),室外不同播种时间的均为10.0 mm。（2）沙米出苗水分阈值的影响因素除种子本身的阶段性休眠特征外,还与环境气温有关;环境气温越高,沙米出苗的水分阈值下限越低;反之则越高。该研究首次提出沙米出苗水分阈值下限界定的方法,为开发利用沙区非耕地人工种植沙米促进出苗技术和水分利用等方面,提供了基本是眼数据和生产应用的可能。。     

氮素供应对欧洲云杉根系生长发育效应分析

研究氮素供应对欧洲云杉[Picea abies (L) Karst]无性系根系生长发育的施肥效应,进而为该树种苗木根系发育的施肥调控提供依据。以欧洲云杉优良无性系pab081140 3年生苗木为试材,对不同氮素供应剂量下盆栽植株的根系生长发育指标进行测定分析。结果表明：与对照相比,测试剂量N-6（含氮量为46%的尿素6 g/株）、N-9（含氮量为46%的尿素9 g/株）、N-12（含氮量为46%的尿素12 g/株）均促进了根长、根表面积、根平均直径与根体积的生长,同时提高了根系生物量、植株总生物量和根系含氮量及植株总含氮量的水平,根系生物量占植株总量的比值和根冠生物量比值随之提高,但不同剂量的施肥效应存在差异;其中,N-9剂量处理下的欧洲云杉根系形态指标均是对照的1.3倍以上（1.38~1.89倍）,而根系生物量、植物总生物量、根冠生物量的比值也显著高于对照(P<0.05);此外,根含氮量与植株总含氮量分别比对照提高了73.2%和80.9%。由此可知,N-9剂量对欧洲云杉pab081140无性系根系生长发育的促进效果最为明显。     

云南松蹲苗的特征分析

为了解云南松苗木蹲苗的形态特征及生长和器官生物量累积等,采用U_6(6~4)均匀和L_9(3~4)正交设计的同期(4月)前后1年采用不同措施培育苗木,形成蹲苗和无蹲苗的2类苗木,前者于苗龄240 d和三年生(27个月),后者则苗龄210 d和二年生(15个月)时观测和测定相关指标,进行数据和形态特征分析。1)前者的地径和苗高分别为6.88 mm和9.6 cm,后者的则为5.21 mm和17.2 cm;蹲苗苗木明显呈现地径较大、苗高生长缓慢和胚轴膨大的现象; 2)蹲苗苗木根系和胚轴占全株生物量和含水率(21.7%、13.3%和15.4%、15.8%)高于无蹲苗的(7.5%、8.1%和6.5%、8.5%); 3)虽然蹲苗的苗龄较无蹲苗的大1年,但其生物量积累极显著地缓于后者(p0.01;处理组合间生物量前者为2.21～3.46 g·株~(-1),后者为2.84～5.78 g·株~(-1)),即蹲苗的苗木生物量积累极其缓慢。云南松蹲苗苗木在形态特征、生长、器官和全株生物量积累和器官含水率分配等均与无蹲苗苗木形成极其明显的差异。     

南方红豆杉人工林培育模式对生物量及其分配格局影响

本研究通过了解南方红豆杉生长、干形变化、生物量积累与分配格局的培育模式响应机制,为南方红豆杉林下栽培体系提供理论基础,在福建明溪对林下套种与纯林培育模式12年生南方红豆杉的生长、干形、生物量积累与分配进行调查。结果表明,培育模式对南方红豆杉树高、胸径、冠幅、单株材积、高径比和生物量有显著性影响,林下套种显著促进南方红豆杉生长,改良干形品质,利于南方红豆杉构件生物量及总生物量积累;不同培育模式中南方红豆杉生物量分配比大小顺序均为干＞枝＞叶;培育模式对南方红豆杉生物量分配比与构件生物量比有着显著性影响,林下套种南方红豆杉增加枝、叶、干等地上生物量分配比,降低根系生物量分配比;林下套种的生物量更趋向地上部分、干和叶的分配;南方红豆杉人工林林下套种较纯林培育模式促进生物量高效积累与有效分配。     

盐胁迫对苜蓿生理性状和生长性状的影响

为改良利用河北东部盐碱土壤,试验选用河北沧州东部黄骅地区的重度盐碱土壤与砂壤土按一定比例混合,探究耐盐型和敏盐型2种苜蓿在盐胁迫下的生长性状和生理特性表现。结果表明：不同比例的盐碱土会对苜蓿的生长产生抑制作用,耐盐型苜蓿‘中苜3号’在盐碱土:砂壤土不超过1:2的条件下,株高、地上生物量、主枝侧枝数、地下生物量和根系长度无显著影响,且盐碱土:砂壤土低于1:2时,盐胁迫对‘中苜3号’生长具有促进作用,但当盐碱土:砂壤土超过1:2时,盐胁迫对‘中苜3号’的生长产生显著的抑制效果。而敏盐型‘WL440HQ’则表现为随着盐碱土比例的增加,株高、地上生物量、地下生物量、主枝侧枝数和根系长均显著下降。盐胁迫会使苜蓿叶片内脯氨酸和丙二醛含量增加,‘中苜3号’在YJ-2（盐碱土:砂壤土=1:2）处理下脯氨酸和丙二醛在苗期-初花期的增加量最大,说明‘中苜3号’在盐碱土:砂壤土=1:2时适应性最强。在河北沧州东部重度盐碱地,在选用耐盐苜蓿品种‘中苜3号’时,可以通过盐碱土:砂壤土=1:2的混合比例,既不影响苜蓿正常的生长,还可改良利用该地区盐碱土壤。     

Biological Characteristics of Vegetative Growth of Cultivated Saussurea involucrata in a Low Altitude Region

[Objective]To study the biological characteristics of vegetative growth of cultivated Saussurea involucrata in a low altitude region.[Methods]The measure agronomic traits of cultivated S. involucrate were researched,including leaf number,plant height,root length,and fresh weight under different treatments. [Results]The seedling emergence rate could be improved if plots were covered with a straw mat immediately after sowing the seeds. The biomass of spring-sown plants was significantly higher than that of autumn-sown plants. The growth of 1-year-old seedlings was slow from germination to the 45 thday,whereby it increased and reached a moderate rate by 70 d. Characteristics of perennial cultivated plants,such as plant height and leaf number,were stable and changed a little within the current year. Growth of seedlings increased under 60% shade cloth until the stage of 5 true leaves. Cultivated S. involucrata also demonstrated drought tolerance. One-year-old plants could be cut twice in the same year,but 2-and 3-year-old plants four times. Regenerative ability could be promoted by cutting,which was also improved resilience to high temperature and pest damage. [Conclusions] Cultivated S. involucrata in a low altitude region had its own biological characteristics of vegetative growth.     

Preliminary Screening of Low Nitrogen-Tolerant Cotton Genotypes at Seedling Stage

[Objective] The aim of this study was to screen cotton varieties (lines) able to tolerate low nitrogen conditions, thereby tapping the potential of cotton to absorb and utilize nitrogen. [Method] This study analyzed the differences and correlations between the main cotton agronomic traits under two nitrogen levels using the sand culture method and 270 cotton varieties from different generations in three major cotton regions as materials. Principal component analysis and the membership function method were used to screen for low nitrogen-tolerant cotton varieties. [Result] The seven agronomic traits of 270 varieties varied greatly with different nitrogen levels. The coefficients of variation were all above 10 except for the SPAD value in four batches, and root biomass and cotton plant biomass in the first batch under low nitrogen level. The variation coefficient of nitrogen accumulation reached 60.02. The maximum relative value of SPAD, leaf area, and root biomass was greater than 80% in the first batch. The maximum relative values of SPAD, plant height, root biomass, shoot biomass, and cotton plant biomass were greater than 80% in the third and fourth batches, indicating that there are low nitrogen-tolerant genotypes in the selected materials. [Conclusion] Preliminary screening identified 32 low nitrogen-tolerant cultivars, including CCRI 35, CCRI 69, Yumian 12, Xinluzao 12, and Xinluzao 23. Furthermore, 32 varieties sensitive to nitrogen stress, including CCRI 64, CCRI 662, Xinluzhong 15, and Xinluzao 53, were identified.     

赣中地区麻栎优良种源初步筛选

通过对幼林期麻栎种源试验林进行生长调查,初步筛选出适宜赣中地区发展的麻栎优良种源。在赣中地区的永丰官山林场采用完全随机区组设计,开展了麻栎种源试验,调查了32个种源2年生麻栎的保存率、苗高、地径和生物量的变化。结果表明:大多数种源麻栎保存率在89%以上,苗高和地径年生长量以及单株生物量在不同种源之间具有较大变异;通过聚类分析将参试的32个种源划分为3组,第1组为优良种源,包括浙江、贵州等地的11个种源;第2组为较差种源,第3组为一般种源。研究结果为该区域麻栎优良种质资源初步筛选提供了依据。     

Effect of Spatial Soil Moisture Stress on Cotton Root Architecture

[Objective] This study aimed to explore the effects of spatial soil moisture stress on cotton root growth, and to analyze the corresponding changes in cotton root architecture. [Method] To produce soil moisture spatial stress, cotton spacing was set at 30 cm. The cotton was all irrigated on one side of the pole (the side sampling point). By excavating the cotton root, analysis of the main root bifurcation, which was cultivated away from the irrigation point, could be undertaken. [Result] The analyses of the cotton A (the nearest plant to the irrigation location) root system showed that soil moisture near the irrigation point was distributed uniformly. The root system architecture of the cotton cultivated near the irrigation point mostly presented a symmetrical "umbrella" pattern; the difference in root diameter between the main and lateral roots was 5–6 mm, and the average angle between them was 70°–80°, which decreased with the increase in cotton growth stage. Soil moisture spatial stress influenced the cotton plant C, which was cultivated away from the irrigation point, such that the root system architecture was asymmetrical. The roots of cotton plant C grew towards the high soil moisture zone; 48.15% of the lateral roots became thicker, which acted as a bifurcated main root. The difference in diameter between the bifurcated roots was 1–4 mm, and the average angle of the bifurcated roots along the vertical direction was between 20°–37°, which increased with the increase in cotton growth stage. [Conclusion] The results provide important information on the physiological responses of the cotton root system to the soil moisture environment.     

不同树龄桐花树根系生长和根系活力的比较研究

为探索树龄对根系生长和根系活力的影响,以1年龄和2年龄桐花树为试验材料,对不同树龄桐花树(Aegiceras corniculatum)根系生长和根系活力进行比较研究。结果表明：处理360天后,2种树龄的桐花树年生物量均有增加,2年龄单株生物量是1年龄的2.45倍。根生物量在单株生物量中所占的比重,随着树龄的递增呈减小趋势。1年龄根数、根长和根粗的年增量均显著大于2年龄的;两者的根系含水量均呈先升后降的趋势,2年龄根系活力较1年龄的相对稳定些。试验表明,不同树龄的桐花树根系生长和根系活力有显著差异。     

不同浓度腐殖酸对油菜苗期生长及生理特性的影响

以油菜品种Cao221167为试验材料,探究水培条件下腐殖酸对作物苗期生长及生理特性的影响。通过设置不同浓度的腐殖酸(0;1‰;2‰;3‰;4‰;5‰)研究其对油菜幼苗生物量、株高、根系特征、叶绿素含量、MDA含量以及抗氧化酶活性等的影响。[结果]结果表明,1‰浓度腐殖酸时显著影响油菜幼苗的生物量(地上部干鲜重分别比对照增加18%和12.20%,地下部干鲜重分别比对照增加41.67%和54.70%),添加腐殖酸可以明显提高油菜幼苗根系活力;浓度为1‰时显著促进根系的生长(根长、总根长和根表面积分别比对照增加20.36%、70.49%、30.43%)。在1‰～5‰浓度范围内油菜细胞内抗氧化酶活性先减小后增大,叶绿素含量先增大后减小。因此,一定浓度的腐殖酸可以促进油菜的生长,且1‰～2‰浓度的腐殖酸是油菜苗期生长的适宜浓度,浓度为3‰～5‰时对油菜幼苗的生长具有胁迫作用。     

Molecular marker assisted tagging of morphological and physiological traits under two contrasting moisture regimes at peak vegetative stage in rice (Oryza sativa L.)

Root morphology under well-watered conditions sampled on two occasions and under low-moisture stress was studied in a randomly chosen subset of 56 doubled haploid lines derived from a cross between IR64 and Azucena at two growth stages during the vegetative stage. A molecular map of the same population served as the basis for locating QTLs controlling root morphology and associated traits. The region flanking the RFLP markers RZ730 and RZ801 on chromosome 1 were associated with plant height in all three sampling environments. This position corresponds to sd-1 a semi-dwarfing gene. A total of 15 QTL were detected at the two developmental stages, of which only three QTL were common. Region flanked by RG157 and RZ318 (chromosome 2) contained QTL for root thickness under two different developmental stages. In total, 21 QTL for different traits were detected under low-moisture stress condition. While two QTL for plant height on chromosomes 1 and 3 were common, none of the loci for root morphological traits was common between the two different moisture regimes. The chromosomal segment between RG171 and RG157 contained QTL controlling tiller number per plant, total root length, root volume and total root number per plant. Absence of common QTL for root traits between two developmental stages and two moisture regimes suggests the existence of parallel genetic pathways operating at different growth stages and moisture regimes. Root volume and total root number per plant decreased significantly under stress, whereas maximum root length and plant height exhibited non-significant increases under stress. This revised version was published online in July 2006 with corrections to the Cover Date.     

施磷量对黑木相思苗木生长的影响

为探究黒木相思苗木生长变化对磷肥的反映机制,本研究对1a生黑木相思(Acacia melanoxylon)苗木采用随机区组设计,设置了7个不同施肥量处理(0、50、75、100、125、150、200 mg P/株),测定并分析其苗高、地径、生物量及根系形态指标。结果表明：不同施磷量对苗木高生长、地径、生物量(地上部分、地下部分生物量)以及根系的生长都起促进作用,随时间和施磷量的增加,黑木相思根长、根平均直径、根表面积、根体积、苗高、地径、生物量总体表现均有所增加,总量为100 mg/株的等量施磷量对苗木生长促进作用效果最佳,试验结束时(即施肥第12 wk),该处理的根长、根表面积、根平均直径、根体积、苗高、地径、生物量(地上、地下部分)分别为417.09 cm、35.16 cm2、0.46cm、0.48cm3、36.2mm、2.30mm、1.236g(地上部分)、0.227g(地下部分),其中根长、根表面积、根平均直径、根体积分别比对照增加了81.2%、110.7%、61.2%和127.1%。