栎属4个树种秋冬叶色与生理变化的关系

为了研究栎类树种秋冬转色期叶色变化的生理机制,以栎属4个树种——鲜红栎(Quercus coccinea)、纳塔栎(Quercus nuttallii)、沈氏栎(Quercus shumardi)、针栎(Quercus palustris)为试材,测定其秋冬转色期叶绿素、类胡萝卜素、花色素苷3种色素和可溶性糖、可溶性蛋白质含量变化。结果表明:叶绿素a、叶绿素b、总叶绿素含量均呈先快后慢的下降趋势;类胡萝卜素含量鲜红栎和沈氏栎呈现下降-上升-下降的趋势,其他2个树种呈平缓下降的趋势;花色素苷含量呈波动上升趋势;叶绿素a与叶绿素b的比值变化趋势前中期较为平缓,后期迅速下降;鲜红栎的可溶性糖含量为单峰曲线,其他3个树种呈双峰曲线,与花色素苷相关性不显著;蛋白质含量与花色素苷含量呈正相关。     

叉斑狗母鱼形态性状的相关性及通径分析

为了研究叉斑狗母鱼(Synodus macrops)各形态性状的相关性及对体重的影响,随机选取叉斑狗母鱼150尾,测定体长(X₁)、体宽(X₂)、体高(X₃)、头长(X₄)和体重(Y)共5个性状。通过相关分析和通径分析方法对所测数据进行分析。结果表明：叉斑狗母鱼4个性状与体重的相关关系达到极显著水平(P< 0.01);体长、体宽和体高对体重的通径系数达到了极显著的水平,它们是影响体重的主要指标,其中体长对体重的直接作用最大,其次为体高、体宽;头长通过间接作用影响体重;决定系数分析结果与通径分析结果基本一致。剔除对体重直接作用不显著的性状,建立体长(X₁)、体宽(X₂)、体高(X₃)对体重的多元回归方程：Y=-50.198+0.299X₁+0.695X₂+1.238X₃(R²=0.930)。     

基于通径分析和灰色关联分析舟山近海中国鱚形态性状对体质量的影响

为了研究中国鱚(Sillago sinica)形态参数与体质量的关系,随机选取107尾舟山近海分布的中国鱚为研究对象,测量其体质量(X₀)和11个形态性状：吻长(X₁)、头长(X₂)、体长(X₃)、全长(X₄)、尾柄长(X₅)、尾柄高(X₆)、体厚(X₇)、眼径(X₈)、眼间隔(X₉)、眼后头长(X₁₀)、体高(X₁₁),并进行了相关性分析、多元回归分析、通径分析和灰色关联分析。测定的形态指标和体质量的相关性都达到了极显著水平(P<0.01),其中体长与体质量的相关性最大;剔除存在严重共线性的形态指标后,分别设置与体质量显著线性相关的体长和尾柄高为自变量、并将体质量设为因变量,构建了最优多元线性方程为Y=-87.734+6.174X₃+24.398X₆;通径分析结果显示,对体质...     

秋季不同色泽五叶地锦叶片生理生化特性的研究

为明确秋季不同叶色五叶地锦叶片的生理差异,以秋季同一植株上红色、中间色、绿色三种颜色的五叶地锦叶片为试材,测定了叶片中色素物质含量、酶活性以及叶片可溶性内含物的含量,结果表明:在红色叶片中,叶绿素含量较低,PAL、POD酶活性较高,花青素苷/叶绿素的比值较大,从而使R/G的值增大,叶色显现红色;而在绿色叶片中,叶绿素含量较高,PAL、POD酶活性较小,花青紊苷/叶绿素的比值较低,R/G的值降低,叶片显现绿色.通过可溶性内含物测定可知,在红色叶片中的可溶性糖和蛋白质含量相对较高,与花青素苷/叶绿素的比值达到显著相关水平,表明这些内含物的积累有利于花色素苷的合成.     

播期、密度及施肥对寒地油用型紫苏产量的影响

以“SU-5”为研究对象,通过二次回归通用旋转组合设计,研究播期、密度、复合肥施用量3种因素对寒地油用型紫苏种子产量的影响。结果表明：3个参试因子对寒地紫苏产量的影响是密度>复合肥施用量>播期,寒地紫苏种子产量的二次回归通用旋转组合方程为Y=2214.74973+111.16360X₁+225.68963X₂+190.45268X₃-210.46885X₁ ²-212.67802X₂ ²-126.52061X₃ ²-196.87500X₂X₃。通过方差分析得出,寒地紫苏种子产量大于1 839.38kg/hm ²的理论上组合方案的播期为5月4日,最佳密度为5.0万株/hm ²,最佳复合肥施用量为507.7kg/hm ²。     

小豆缺铁突变体分离群体叶色及产量性状分析

为了鉴定小豆铁吸收代谢突变体作图群体叶色性状的变异及其对产量的影响,本研究调查了‘河北801’(耐缺铁野生型)×FMY011 (缺铁敏感突变体)和MY076 (耐缺铁突变体)×GM352 (缺铁敏感资源)的F₂分离群体的叶色分离情况,测定了叶绿素SPAD值,并分析了其与单株产量及其他农艺性状的相关性。F₂群体分离出新叶黄化和正常单株,其叶绿素SPAD值差异极显著。相关性分析显示SPAD值与单株产量、单株荚数、百粒重呈极显著正相关,缺铁引起的新叶黄化会降低小豆产量。缺铁胁迫验证田间叶色分离表型,结果显示‘河北801’×FMY011群体的叶色表型与田间叶色分离符合度高,新叶黄化F₂单株的F_2:3家系全部黄化,新叶绿色F₂单株胁迫下其96.62%F_2:3家系表现正常绿叶或呈杂合叶色分离,3.38%新叶绿色F2单株胁迫下其F_2:3家系新叶黄化,表型不符合。MY076×GM352分离群体,田间正常叶色与缺铁胁迫鉴定的叶色一致,但田间新叶黄化F<...     

基于高光谱的棉花叶片磷含量估测模型

研究不同施磷条件下棉花叶片叶绿素含量的变化规律，旨在建立基于高光谱的叶片磷含量估测模型，实现棉花叶片磷含量快速监测。在盆栽试验条件下，设置不同的磷肥量，测定棉花功能叶叶绿素含量与磷含量，并利用植被指数和叶绿素含量的相关性构建磷含量的光谱变量，从而实现利用高光谱对棉花叶片磷含量的定量监测。结果表明：(1)棉花播种后100天左右，叶片磷含量与叶绿素呈现显著关系(决定系数R²=0.96)。(2)利用多个植被指数(X)和叶绿素含量(I)的相关性构建倒一叶、倒二叶、倒三叶、倒四叶的磷含量光谱变量，其中各叶片相关性最优的模型：倒一叶(L₁)为I₁=2.6131X_RENDVI-0.4275,X_RENDV为红边归一化植被指数，R²=0.71,RMSE=0.2；倒二叶(L₂)为I₅=0.0142X_TVI+0.3274,X_TVI为三角植被指数，R²=0.76,RMSE...     

碱胁迫对水稻叶绿素及叶片脯氨酸和可溶性糖含量的影响

通过对沙培的4.5叶龄水稻幼苗进行5个浓度的Na₂CO₃+NaHCO₃碱胁迫处理,胁迫20d后,调查顶端叶片相对含水量、叶绿素、脯氨酸和可溶性糖含量。结果表明,随碱浓度增加叶片相对含水量先升后降;叶绿素a、b含量及叶绿素a/b为下降趋势;脯氨酸、可溶性糖含量先降后升;可溶性糖与脯氨酸含量二者具有显著相关性。碱胁迫后,对叶绿素a含量的影响较大,叶绿素b含量相对稳定;水稻通过可溶性糖含量的变化调节顶端叶片含水量及脯氨酸含量,以提高自身的抗逆性和保持新生叶片的活性。     

藜麦主要农艺性状与单株产量的相关和通径分析

为探究藜麦主要农艺性状对单株产量的作用,对10个藜麦新品系的7个主要农艺性状（生育期、株高、茎粗、主茎分枝数、主花序长、主花序分枝数、千粒重）与单株产量进行相关性、多元线性回归和通径分析。结果表明,株高和茎粗与藜麦单株产量呈极显著正偏相关;7个农艺性状可以解释51.60%藜麦单株产量的变异,株高（X₂）和茎粗（X₃）可以解释48.20%藜麦单株产量的变异,最优回归方程为Y=-102.340+1.040X₂+3.257X₃;株高和茎粗对藜麦单株产量的直接影响最大。因此,在适宜种植密度基础上,将适当提高株高和茎粗作为云南昆明及周边地区高产藜麦选育的方向。     

玉米F2群体轴部相关性状的数量遗传分析

本研究采用遗传模型预测的方法，探究玉米轴部性状的遗传机理，以期为育种家指明育种方向，提高育种效率。以FBHJ和MBUB两亲本组配的含390个家系的F₂群体为材料，利用植物数量分离分析软件包中的F₂单世代分析方法，对其穗轴长、粒长、穗轴粗、粒宽、穗轴重、百粒重、粒厚等7个轴部相关性状进行数量遗传分析、相关分析以及回归分析。结果表明，穗轴粗、粒长、粒宽3个性状最适遗传模型为A-0，即无主基因遗传；穗轴重和粒厚受2对主基因控制，主基因存在加性-显性-上位性，符合B-1模型；穗轴长和百粒重由1对主效基因控制，最适模型分别为A-1、A-3，各模型主基因遗传率介于28.37%～59.11%，其中百粒重性状的遗传率最大。各性状均与百粒重呈极显著正相关。百粒重(Y)对其他农艺性状的回归方程为Y=-57.126+0.176X₁+3.069X₂+2.890X₃+5.108X₄，拟合度为0.723。通径分析中粒宽的间接作用和粒长的直接作用表现最大。这一研究结果为玉米轴部性状的遗...     

紫叶加拿大紫荆叶色表达期相关物质的研究

以紫叶加拿大紫荆（Cercis canadensis ‘Forest pansy’）为试材,研究其在山东地区叶色表达期叶片中叶绿素、类胡萝卜素、花青苷与可溶性糖等叶色相关物质的变化。结果表明：在叶色表达期,随着天数的增加,花青苷含量总体呈下降的“M”型趋势,叶绿素和类胡萝卜素含量逐渐升高,可溶性糖含量的变化为无规律的多峰曲线;叶片中叶绿素（r=-0.681**）、类胡萝卜素（r=-0.757**）与花青苷含量均呈极显著负相关关系,可溶性糖与花青苷含量不相关;叶绿素和花青苷含量呈对数曲线关系,类胡萝卜素与花青苷含量呈指数曲线关系。     

红叶山茶(Camellia japonica)叶片色素含量与叶色参数的相关性分析

以3个红叶山茶品种‘红叶黑魔法’、‘黑魔法’和‘黑蛋石’为试验材料,分别测定叶片不同发育阶段叶绿素、类胡萝卜素、总花青苷含量及叶色参数L~*、a~*、b~*值,并通过相关性分析探讨叶色参数与叶片色素含量变化之间的关系。结果表明,首先,3个不同发育阶段叶片中叶绿素a、叶绿素b和类胡萝卜素含量呈上升趋势,不同品种同一发育阶段的色素含量相近。‘红叶黑魔法’和‘黑蛋石’叶片总花青苷含量在新叶展开10 d左右达到最大值,此后极显著下降,而‘黑魔法’叶片的花青苷含量则变化不大。其次,从色素比值来看,在新叶展开10 d时,花青苷的所占比值最大,‘红叶黑魔法’和‘黑蛋石’的花青苷比值分别达到87.88%和79.08%,极显著地高于叶绿素所占比值。到50 d时,花青苷比值下降至31.74%和23.68%,且3个品种花青苷含量相近,而叶绿素和类胡萝卜素比例则显著增加,这一结果较好地解释了这3个品种叶片的呈色变化,说明花青苷含量及其各种色素含量的比例变化是导致红叶山茶叶色变化的主要原因。最后,3个品种的a*值均与花青苷含量呈显著正相关,而与叶绿素a、叶绿素b、类胡萝卜素呈负相关,a~*值可作为描述红叶山茶品种叶色变化的代表性参数。     

花铃期增温对棉花干物重累积的影响及其生理机制

以遗传背景相近的棉花(Gossypium hirsutum L.)品种泗棉3号和泗杂3号为材料,于2010年在南京农业大学牌楼试验站(118º50′E, 32º02′N)模拟全球温室化气候,研究花铃期增温对棉花干物质累积的影响及其生理机制。结果显示,增温2~3℃(龄期日均温33.5~35.2℃)的条件下,主茎功能叶SPAD值降低,蒸腾速率(T_r)、气孔导度(G_s)、胞间CO₂浓度(C_i)上升,但净光合速率(P_n)下降;棉铃对位叶可溶性蛋白含量大幅上升(Δ%>50%)、可溶性糖及可溶性氨基酸含量小幅下降(P<0.05)、C/N值显著下降(P<0.05);叶片POD、CAT活性大幅下降、MDA含量显著上升;泗杂3号相关指标变化幅度较泗棉3号小。说明尽管2~3℃的增温幅度较小,但在花铃期日均温(33.5~35.2℃)的条件下,植株已处于显著的热胁迫状态,光合产物累积能力受到抑制,棉铃对位叶光合产物输出能力显著下降, 棉株总干物质累积量下降20%左右;增温条件下植株水分吸收能力下降并因此受到一定程度的水分胁迫,但此条件下光合能力下降主要由非气孔因子所致,与叶片膜结构的严重受损关系密切;泗杂3号抗高温能力高于泗棉3号。     

Quantitative trait loci mapping of seed colour,hairy leaf,seedling anthocyanin,leaf chlorosis and days to flowering in F2 population of Brassica rapa L.

A diversity arrays technology (DArT) map was constructed to identify quantitative trait loci (QTL) affecting seed colour, hairy leaf, seedling anthocyanin, leaf chlorosis and days to flowering in Brassica rapa using a F₂ population from a cross between two parents with contrasting traits. Two genes with dominant epistatic interaction were responsible for seed colour. One major dominant gene controls the hairy leaf trait. Seedling anthocyanin was controlled by a major single dominant gene. The parents did not exhibit leaf chlorosis; however, 32% F₂ plants showed leaf chlorosis in the population. A distorted segregation was observed for days to flowering in the F₂ population. A linkage map was constructed with 376 DArT markers distributed over 12 linkage groups covering 579.7 cM. The DArT markers were assigned on different chromosomes of B. rapa using B. rapa genome sequences and DArT consensus map of B. napus. Two QTL (RSC1‐2 and RSC12‐56) located on chromosome A8 and chromosome A9 were identified for seed colour, which explained 19.4% and 18.2% of the phenotypic variation, respectively. The seed colour marker located in the ortholog to Arabidopsis thaliana Transparent Testa2 (AtTT2). Two QTL RLH6‐0 and RLH9‐16 were identified for hairy leaf, which explained 31.6% and 20.7% phenotypic variation, respectively. A single QTL (RSAn‐12‐157) on chromosome A7, which explained 12.8% of phenotypic variation was detected for seedling anthocyanin. The seedling anthocyanin marker is found within the A. thaliana Transparent Testa12 (AtTT12) ortholog. A QTL (RLC6‐04) for leaf chlorosis was identified, which explained 55.3% of phenotypic variation. QTL for hairy leaf and leaf chlorosis were located 0–4 cM apart on the same chromosome A1. A single QTL (RDF‐10‐0) for days to flowering was identified, which explained 21.4% phenotypic variation.     

高温胁迫对水稻光合PSII系统伤害及其与叶绿体D1蛋白间关系

以水稻结实期的人工控温试验测定不同温度处理下水稻旗叶光合速率、叶绿素荧光参数的动态变化,并结合Western印迹与胶体金标记技术对叶肉细胞类囊体膜中D1蛋白的表达检测与活性定位,探讨了高温胁迫对D1蛋白存在形态与活性分布的影响,以及D1蛋白表达与叶片光合速率、PSII荧光参数的联系。结果表明,高温处理下叶片净光合速率下降、PSII潜在活性(F_v/F_o)和PSII光能转化效率(F_v/F_m)降低,且随着高温胁迫时间的持续和叶片功能的衰退,类囊体膜结构损伤越严重,光能转化效率越低;在D1蛋白的两类存在形态中,非磷酸化D1蛋白和磷酸化D1蛋白在高温胁迫下的表达量均有所下降,但前者下降更明显;高温处理下控制D1蛋白表达的叶绿体psbA基因在转录水平呈下调表达,使D1蛋白合成及周转过程受到抑制,进而类囊体膜PSII反应中心的功能受损与叶绿体光合效率下降,揭示高温胁迫对叶片PSII系统的伤害受D1蛋白磷酸化过程和psbA基因表达变化的共同作用,进而影响不同水稻品种在高温胁迫下的光合速率和耐热性。     

食用向日葵主要农艺性状与产量的多元分析

为选出适合新疆气候及种植模式的优质高产食葵新品种，以20 个山西作物所提供的食葵品种为材料，采用相关分析、灰色关联度、回归分析和主成分分析法，探讨食葵农艺性状与产量之间的关系。研究结果表明：（1）食葵主要农艺性状变异范围为3.41%~17.9%，食葵平均花盘重的变异系数较大，茎粗百粒重和花盘直径次之，叶片数等较小，生育期最小。（2）食葵产量与结实率呈极显著正相关，生育期与叶片数和茎粗呈显著正相关，株高与茎粗、平均花盘重和籽粒宽度呈显著正相关，百粒重和平均花盘重、籽粒长度及籽粒宽度呈显著正相关。（3）食葵品种各性状与产量间的关联度大小依次是叶片数＞生育期＞籽粒饱满度＞花盘直径和株高＞茎粗＞出仁率＞结实率＞籽粒长度＞百粒重＞籽粒宽度。（4）影响食葵产量的关键农艺性状以结实率、出仁率为主。     

A Crop–Weather Model for Prediction of Rice (Oryza sativa L.) Yield Using an Empirical-Statistical Technique

Rice is the staple food in many countries and is grown in varied climates from per‐humid to semiarid areas. Crop–weather models were used to predict rice yield in India. However, in spite of a significant influence of solar radiation on rice yield, none of these models used solar radiation as one of the predictors. In this paper, an attempt was made to predict the first season (June–September) rice yield at Coimbatore, Tamil Nadu, India by including solar radiation as one of the predictors. Ten years (1987/88–1996/97) data were used for the study. Seven predictors viz., percentage of rice area during first season (X₁), number of days with minimum temperature below 22 °C in August and September (X₂), average daily maximum temperature for three months (July, August and September; X₃), average daily minimum temperature for three months (July, August and September; X₄), total of average sunshine hours in August and September (X₅), and total rainfall of July, August and September (X₆) total average solar radiation of August and September (X₇) were selected based on earlier report. Full model and stepwise regression analysis were performed using MSTAT computer package. The full model regression without solar radiation as predictor (Model I) recorded comparatively less R² (0.6292). Inclusion of solar radiation (Model II) enhanced the R² value considerably (R²=0.9464). Seven variables were further subjected to stepwise regression analysis and only four predictors were retained in the final model (Model III) with an R² value of 0.9234. The model III with minimum parameters Y=22119.5758 + 19.6898, X₁ ? 150.9261, X₂ ? 1126.7501, X₄ + 0.7179 X7 can be used to predict the first season rice yield (Y) at Coimbatore, India.     

Agronomic and morphological characterization of Agrobacterium-transformed Bt rice plants

The agronomic and morphological characteristics of Agrobacterium-transformed rice plants carrying the synthetic cry1Ab or cry1Ac gene were investigated. Tremendous variations in plant height, seed fertility, grain size and other traits were seen in 80 T₁ lines, derived from 80 T₀ plants of 9 rice varieties. On average, about 33% T₁ lines had either morphological or agronomic variant plants. Most of the variations in T₁ plants had no significant correlation with transgene insertion and were proved heritable to their progenies. Genetic analysis in T₃ or T₄ generations showed some simple mutations such as chlorophyll deficiency and stunted plants were independent of transgene insertion and seemed to be controlled by a pair of single genes. However, in two independent transgenic progenies of Xiushui 11, all plants homozygous for transgenes showed dwarfism while all hemizygous and null segregants had normal plant heights. Two advanced homozygous Bt lines, KMD1 and KMD2, were developed from these two progenies. Comparison of the agronomic traits of KMD1 and KMD2 with their parent displayed marked differences among them in terms of seedling growth, tillering ability, yield components and yield potential. The genetic variation observed was generally not linked to the transgene locus and was ascribed to somaclonal variation, but other causes might also exist in particular cases. The results are discussed in the context of choosing appropriate transformation methodology for rice breeding programs. This revised version was published online in August 2006 with corrections to the Cover Date.     

Genomic characterization of drought tolerance-related traits in spring wheat

Drought tolerance was investigated in ‘C306’, one of the most drought tolerant wheat cultivars bred in India in the 1960’s. An intervarietal mapping population of recombinant inbred lines of the cross ‘C306’ × ‘HUW206’ was evaluated for drought tolerance components, namely potential quantum efficiency of photosystem (PS) II (F_v/F_m), chlorophyll content (Chl), flag leaf temperature (Lt), and grain yield per plant (Gyp) under stress. Three independent experiments were conducted under well-watered and water-stressed conditions in greenhouses and growth chambers at Kansas State University (USA). Five hundred and sixty microsatellite markers covering the entire genome were screened for polymorphism between the parents. A QTL (QLt.ksu-1D) for Lt (low flag leaf temperature under stress) on the short arm of chromosome 1D between markers Xbarc271 and Xgwm337 at LOD 3.5 explained 37% of the phenotypic variation. A QTL for F_v/F_m (QF _v /F _m .ksu-3B) and Chl (QChl.ksu-3B) controlling quantum efficiency of PS II and chlorophyll content under stress were co-localized on chromosome 3B in the marker interval Xbarc68–Xbarc101 and explained 35–40% of the phenotypic variation for each trait. A QTL (QGyp.ksu-4A) for Gyp on chromosome 4A at a LOD value of 3.2 explained 16.3% of the phenotypic variation. Inconsistent QTLs were observed for F_v/F_m on chromosomes 3A, 6A, 2B, 4B, and 4D; for Chl on 3A, 6A, 2B and 4B; and for Lt on 1A, 3A 6A, 3B and 5B. The identified QTLs give a first glimpse of the genetics of drought tolerance in C306 and need to be validated in field experiments using the marker-phenotype linkages reported here.     

Relationships between Grain Yield, Flag Leaf Morphology, Carbon Isotope Discrimination and Ash Content in Irrigated Wheat

The purpose of this study was to examine how differences in leaf angle, leaf rolling (LR) and glaucousness (GL) can modify yield components and leaf physiological traits in wheat. A set of 167 lines derived from a cross between two high‐yielding bread wheat cultivars differing for these traits was grown under flood irrigation and high evaporative demand in the north‐west of Mexico. Area, mass per unit area and chlorophyll content of the flag leaf were assessed. Carbon isotope discrimination (Δ) and ash content (m_a) were also measured. A significant correlation was found between grain yield (GY) and both Δ and m_a suggesting that, despite well‐watered conditions, leaf stomatal conductance was the main yield‐limiting factor. Leaf posture and LR did not significantly affect yield, Δ and m_a. Higher grain weight was noted, however, in lines with droopy flag leaves. Erect leaves had higher mass per unit area. GL was associated with a significant increase in GY and grain weight. Glaucous lines also had higher Δ and m_a, suggesting higher transpiration rate and lower transpiration efficiency. The study confirms that Δ and m_a represent promising criteria for GY in wheat and provides evidence that GL can contribute to higher yield, even under irrigated conditions.