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1.
亚洲玉米螟为害后玉米冠层光谱变化和产量损失研究   总被引:4,自引:0,他引:4  
2006年在河北农林科学院植保所农场夏播高感亚洲玉米螟的玉米品种郑单958上,于大喇叭口期人工接种2龄玉米螟幼虫以造成不同梯度为害,利用便携式遥感光谱仪(ASD FieldSpec UV/VNIR)在玉米不同生育期收集冠层光谱信息,调查食叶级别,并在收获时统计蛀孔率和产量。结果表明:(1)各生育期食叶级别和对应生育期内的冠层光谱反射率值呈显著负相关,且各个级别之间方差分析差异显著;(2)各波段冠层光谱反射率值和每株虫孔数量的相关性分析得到相关性曲线,750~900nm相关系数较高,可作为监测的敏感波段;(3)乳熟期光谱数据、平均每株虫孔数量和产量及产量损失率之间均可建立极显著回归方程。用光谱仪所测数据估测产量损失率的精确度比用传统查虫数据估测产量损失率的精确度高,且省时省工。  相似文献   

2.
Five chickpea cultivars, Chitoui, Neyer, Kasseb, Beja 1 and Bouchra, were planted on three sowing dates at two Experimental Stations in Tunisia: Bou Salem in the north and the more southerly Mornag, where the climate is drier. Severity of blight, caused by Ascochyta rabiei, was measured on a 1–9 scale (defined) on vegetative parts and on pods as percent infected and percent infected that were empty. At both locations, disease was essentially absent on plants sown on the third dates but present on plants sown on the two earlier dates. At Bou Salem, disease severity was highest for the second sowing date whereas at Mornag it was highest for the first sowing date; but for each sowing date, disease severity was lower at Mornag than at Bou Salem. Yield components were measured as number of pods per plant, number of seeds per plant, number of seeds per 100 pods, 100 seed weight and weight of seeds per plant. Both disease severity and yield differed significantly among sowing dates (differently at each location) and also among cultivars for each sowing date, these differences depending both on sowing date and location. A lower yield was always associated with a higher disease severity, although the quantitative relationship differed between cultivars and locations. Cultivar Beja 1 had the lowest vegetative disease scores at both locations and both sowing dates 1 and 2. Beja 1 also scored well for all yield components. Plants sown on the third (latest) date gave the highest yields for all cultivars at both locations (except for an unusually high yield of Neyer at Mornag on sowing date 2), in some instances being more than double those from the earlier sowing dates. Thus, in contrast to other studies, late sowing did not result in yield loss.  相似文献   

3.
冬小麦冠层温度及其生物学性状对施氮量的反映   总被引:2,自引:1,他引:1  
在大田试验下研究了0 kg/hm2(N0)、120 kg/hm2(N120)、240 kg/hm2(N240)、360 kg/hm2(N360)四个氮肥处理对冷型小麦陕229、暖型小麦NR9405、不稳定型小麦小偃22三个品种拔节至成熟期间的冠层温度、产量及其构成因素、灌浆结实期蒸腾速率的影响及关系。结果表明:各个生育期N0冠层温度皆高于氮肥处理,随着生育期后延差异有上升趋势,在灌浆结实后期达最大。拔节期各施氮量间差异不显著;孕穗-开花期总体表现为N240处理冠层温度最低,N120和N360差异不显著;灌浆结实前期为:N360N120N240,差异在0.1~0.6℃之间,中、后期总体为N120N240N360,差异在0.1~1.5℃之间。三品种间差异也在灌浆结实后期达最大,但小麦冷暖型不随着施氮肥的增加而发生根本变化。灌浆结实各个时期蒸腾速率与冠层温度呈极显著负相关;拔节至灌浆结实期的冠层温度同理论产量皆呈极显著负相关,在灌浆结实后期相关性达最大;产量构成因素中,穗粒数、成穗数与各个时期的冠层温度均呈显著负相关,分别在拔节期和灌浆结实后期相关性达最大,千粒重与拔节期冠层温度呈极显著正相关,与孕穗期和开花期冠层温度呈显著正相关。灌浆结实中后期的冠层温度在评价小麦产量上具有较高的可靠性,可作为指导田间施氮肥的一个指标应用。  相似文献   

4.
宁夏南部山区冬小麦抗旱指标鉴定研究   总被引:1,自引:0,他引:1  
为了更快速有效地利用现有资源,选育适宜宁南山区旱地种植的冬小麦新品种,本试验通过抗旱系数、主成分分析、相关分析及聚类分析等方法对8个品种12个性状进行研究。结果表明:8个品种根据抗旱系数不同,可分为抗旱性强、中、弱3个等级;12个性状的主要信息主要集中在4个主成分中,累积贡献率达93.40%,这4个主成分因子主要反映产量、抗旱系数、穗长、穗粒数、千粒重、单株粒重、株高、不实小穗数、颖花结实率9个性状。产量、穗下节长和株高与抗旱系数间为显著或极显著正相关。通过聚类分析将8个品种聚为3类,第一类包含3个品种,分别是Z0217-3,Z0231-3和对照中引6号,这三个品种的产量、抗旱系数、穗下节长、千粒重及株高等主要指标在第三类和第二类之间,但穗长、穗粒数及单株粒重在三类中平均值最低。第二类包含2个品种,分别是98-5808-1和Z0228-2-1,这两个品种的穗粒数、单株粒重和不实小穗数三个指标平均值最高,但产量、抗旱系数、穗下节长、千粒重等指标平均值最低。第三类包含3个品种,分别是Z0349-4,08AWS089和晋太0509,这三个品种平均产量高,抗旱系数高,平均穗长最大,平均穗下节长最长,平均结实小穗数最多,千粒重最大、株高最高。  相似文献   

5.
针对丘陵双季稻区易发生季节性干旱导致养分供应受阻、水稻生长发育受影响、产量下降等问题,研究了干旱条件下5种养分管理措施(即T1:增施钾肥+喷清水;T2:叶面喷施0.2%Zn SO4;T3:增施钾肥+叶面喷施肥0.2%Zn SO4;T4:提高后期施N比例+喷清水;CK:常规施肥+喷清水)对双季晚稻生长发育、产量形成以及产量的影响。结果表明,分蘖期干旱胁迫下,不同养分管理对双季晚稻生长发育和产量的影响具有明显的差异,其影响程度由强到弱依次为:T3T1T2T4CK。T3在分蘖期干旱胁迫下能有效促进水稻分蘖能力,提升苗峰值和有效分蘖数,最高分蘖数比CK高7.26%,并显著提高拔节期和齐穗期的叶片SPAD值、叶片光合速率和叶片蒸腾速率以及根系活力,同时还显著增加拔节期、齐穗期和成熟期地上部单株干物重,改善植株干物质的积累,其增幅分别在2.19%~25.22%,从而显著提高双季晚稻每公顷有效穗数、每穗实粒数、每穗总粒和结实率等产量构成因素,最终使双季晚稻在干旱胁迫条件下获得较高产量。T3的产量在所有处理中最高,达10.07 t·hm~(-2),分别比T1、T2、T4及CK高6.34%、7.70%、14.17%和25.56%。  相似文献   

6.
穗期玉米螟为害对夏玉米产量损失影响初报   总被引:3,自引:0,他引:3  
以人工接卵方法研究夏玉米小黄品种乳熟到完熟阶段玉米螟幼虫数量与产量的相关,得知虫口密度与产量损失呈直线相关。单株每增加幼虫1头,百株产量损失0.17斤,损失百分率为0.89%,影响极小。如按每亩2300株计,在上述玉米生育阶段内无虫时的产量436斤,单株平均有虫1头时,每亩损失约4斤。作者初步认为:北京地区夏玉米使用颗粒剂一次防治螟害,在玉米较早生育期(如心叶末期或开花授粉期)施药,效果应优于在卵高峯前后施药。  相似文献   

7.
对180份苦荞种质资源的12个主要农艺性状进行遗传多样性分析、主成分分析以及聚类分析。结果表明,180份苦荞种质间株粒重和株粒数的差异较大,变异系数均高于60%。根据苦荞种质性状间的遗传差异,对12个主要农艺性状进行主成分分析,得到的4个主成分因子累计贡献率达82.729%,第1主成分反映籽粒形状,第2主成分反映产量,第3、4主成分分别反映籽粒大小和株型。聚类分析把180份苦荞种质划分为3个类群,类群Ⅰ可以作为选育矮秆、特异粒形品种的优良亲本;类群Ⅱ可作为选育高秆品种的优良亲本;类群Ⅲ可作为选育高产、大粒品种的优良亲本。从矮秆、高产和大粒3个方面,筛选出矮秆材料灵石苦荞、安泽苦荞、苦荞60、苦荞62,高产材料二各苦荞、武乡苦荞、苦荞27、老鸭咀苦荞、苦荞34、苦荞35和大粒材料泸西苦荞、额角瓦齿、姚安苦荞1、苦荞61,共14份优异苦荞种质资源。  相似文献   

8.
Epidemics of faba bean rust (Uromyces viciae-fabae) differing in duration and final severity were induced by a point inoculation. Relationships between disease severity observed on three canopy layers (top, middle and bottom) at different assessment dates and yield components (grain weight per stem, average grain weight, number of grains per pod and number of pods per stem) were established. Epidemics occurring after the initiation of pod setting had no effect on yield components. Earlier epidemics significantly decreased the grain weight per stem, the average grain weight, and the number of pods per stem, but only marginally affected the number of grains per pod. The yield components generally decreased with increasing severity level, but a few parabolic relationships were observed at a late stage in crop development. The effect of rust on yield components could be predicted by a critical point model using disease severity assessed on the middle or bottom canopy layer in the mid-flowering stage. Rust severity greater than 5% during that critical stage would substantially decrease final yield, and fungicide spraying against rust would be advised.  相似文献   

9.
利用GGE双标图、变异系数法、相关性分析、多元回归和聚类分析等方法,分析了2003—2016年共14 a国家绿豆品种区域试验中来自内蒙古自治区、黑龙江省、吉林省、辽宁省、山西省等12个绿豆主产省(市、自治区)的29个育种单位提供的130个参试品种的生育天数、株高、主茎节数、主茎分枝数、荚长、单株荚数、荚粒数、千粒重以及产量在春播组和夏播组的变异,并比较了性状间的相关性以及不同育种单位选育的绿豆品种的性状差异。结果表明:2003—2016年春播组和夏播组绿豆产量分别增加14.0%和25.4%,年均增幅分别为1.0%和1.8%;主茎分支数分别减少12.0%和15.9%;其他性状变化不明显。春播组绿豆主要农艺性状的变异系数为5.14%~17.01%,均值为11.33%;遗传多样性指数为1.91~2.08,平均为1.99。夏播组绿豆主要农艺性状的变异系数为5.96%~19.99%,均值为12.52%;遗传多样性指数为1.98~2.17,平均为2.07。相关性和偏相关性分析表明,春播组中产量与荚长、单株荚数和荚粒数显著正相关,与其他性状的相关性不明显;夏播组中产量与单株荚数和荚粒数显著正相关,与株高、主茎分支数和荚长显著负相关。多元回归分析表明,春播组绿豆生育天数、株高、主茎分支数、荚长和单株荚数共同决定产量60.9%的变异;夏播组绿豆株高、主茎分枝数、单株荚数、荚粒数和千粒重共同决定产量87.7%的变异。依托品种选育区域的聚类分析表明,65个春播组品种被分为4类,在北京市、河北省、山西省、河南省、山东省、吉林省和陕西省综合表现较好;65个夏播组品种被分为6类,在河南省、河北省和山东省综合表现较好。2003—2016年,国家每轮区试的绿豆品种产量稳步提升,表明我国绿豆育种水平有了一定提升;但品种遗传基础狭窄,育种方法多样化程度较低,缺少突破性品种。  相似文献   

10.
在大田环境下,研究了5种旧膜处理方式对旱地胡麻生育进程中叶面积、干物质累积、净同化率(NAR)、相对增长率(RGR)及产量和产量构成因子的影响。结果表明:在花前营养生长期,播种前收除旧膜并覆盖新膜免耕播种(T4)与当年收除旧膜并整地覆盖新膜、翌年播种(T5)处理较当年全膜覆盖作物收获后收除旧膜、翌年整地播种(T6)(无覆膜对照)对提高胡麻叶面积影响最为显著,但花期及花后各处理与对照相比无显著差异。胡麻总干物质在花前T4、T5处理较T6积累量最多,其中分器官茎、叶干物质呈现相同趋势,花后T5处理跃居首位。NAR因处理和生育时期不同而有所差异,表现为生育前期T4高于其它处理,生育后期T5处理最优的结果;RGR在枞形期-现蕾期T4、T5处理较对照分别上升20.45%和16.12%,而花期T5处理表现最高,二者均呈现出与其干物质积累动态相一致的趋势。5种处理方式均提高了有效分枝数和千粒重,对蒴果数和每果籽粒数影响不大,其中T4、T5处理下胡麻籽粒产量分别达到了1 024.95 kg·hm-2和996.15 kg·hm-2,比对照显著增产120.91%、114.71%,旧膜留至翌年免耕播种(T1)、在旧膜上覆土免耕播种(T2)、当年作物收获后在旧膜上覆盖玉米秸秆、翌年去除秸秆免耕播种(T3)与对照T6产量差异不显著。可见,收获后留旧膜、翌年收旧膜覆新膜免耕播种的处理方式有利于提高生长速率和干物质累积,进而获得高产,而结合生产效益,收获后留旧膜翌年直接播种(T1)方式为干旱半干旱胡麻种植区旧膜再利用的最优选择。  相似文献   

11.
玉米纹枯病产量损失测定和发生规律   总被引:14,自引:0,他引:14  
不同地区玉米纹枯病产量损失测定结果表明,产量损失与病情严重度级别之间存在着显著的直线相关,严重度每提高一级,产量损失增加约10%左右,在产量损失的构成中,千粒重下降处于主导地位,粒数的减少其次;始病愈早,发病愈重,相应的产量损失也愈大。不同地区,播期不同,发病期亦不同。从生育期来看,却是基本一致的,玉米抽雄期为发病始盛期,乳熟期为发病高峰期。品种间发病差异明显,但未发现高抗品种,目前生产上广泛应用的掖单系统杂交组合,中抗至中感,其丰产性较好。增施钾肥112.5~262.5kg能显著地减轻病害和增加产量,可作为防病措施推广应用。另外,大田调查还发现,轮作、间作和控制种植密度能减轻病害发生。  相似文献   

12.
限量灌溉和施磷对冬小麦生长及水分利用的影响   总被引:4,自引:0,他引:4  
在大田条件下研究了不同灌水和施磷组合对冬小麦生长及水分利用的影响。结果表明:灌水和施磷均可提高冬小麦的株高、生物量、产量及其产量构成。在不同水分条件下,冬小麦的株高随灌水量的增加而增加,水分对冬小麦的产量和千粒重的影响达到显著水平,而不同水分条件对穗长、穗重和穗粒数没有显著影响。在不同施磷处理下,随着施磷量的增加,分蘖数、穗数、千粒重、产量及其灌溉水利用效率有显著增加,但施磷对株高没有显著影响。本试验条件下,施磷量120 kg/hm2时,株高、干物质及其产量达到最大,当施磷量超过120 kg/hm2时,相关物质生产指标呈下降的趋势;灌水量为180 mm与施磷肥量为120 kg/hm2是冬小麦干物质积累和产量的最优组合。  相似文献   

13.
Phoma stem canker of oilseed rape (Brassica napus), caused by Leptosphaeria maculans/L. biglobosa is a globally important disease. Severe phoma stem canker symptoms have been observed on winter oilseed rape in China but the seed yield loss caused by this disease remains unknown. In May 2012 and May 2013, 17 and 13 crops were surveyed, respectively, in seven counties of Hubei Province, central China. Stems with phoma stem canker disease symptoms were sampled for pathogen isolation and identification. Only L. biglobosa was identified by culture morphology and species-specific PCR; no L. maculans was found. To evaluate the yield losses, yield components (number of branches per plant, number of pods per plant, 1000-seed weight, number of seeds per pod) were assessed on healthy and diseased plants sampled from crops in four counties and on plants from inoculated pot experiments (plants of three cultivars were inoculated at the green bud stage by injecting L. biglobosa conidia into the stem between the first and second leaf scars). Results of the field surveys showed that diseased plants had 14–61% less branches and 32–83% less pods than healthy plants, respectively. The estimated seed yield loss varied from 10% to 21% and from 13% to 37% in 2012 and 2013, respectively. In the pot experiments, there were no differences in numbers of branches or pods but there were differences in number of seeds per pod between inoculated and control plants. For the three cultivars tested, the inoculated plants had yield losses of 29–56% compared with the control. This study indicates that L. biglobosa could cause substantial seed yield loss in China.  相似文献   

14.
Inoculation of winter barley plants in a glasshouse with Pyrenophora teres at three different growth stages (GS 11, 13 or 30) greatly decreased root and shoot dry matter production and the size of healthy leaves produced subsequently, but there was no significant yield loss with a single inoculation at GS 11 or 30. Inoculation at GS 13, GS 31 or GS 39 decreased grain yield by 12,17 and 20% respectively, and also straw yield. Larger yield losses resulted from repeated inoculations on five successive occasions (GS 11, 13, 30, 31 and 39) which caused much disease on all leaves throughout the life of the plant. All components of yield measured were decreased by the cumulative effect of successive inoculations; ear number by 15%), grain sites per ear by 20%, grain yield by 48% and straw yield by 32%.  相似文献   

15.
为预测芝麻青枯病造成的产量损失,以茎秆病斑长度为指标确定成熟期芝麻青枯病严重度的分级标准,测定4个芝麻品种在不同青枯病严重度下的农艺性状指标、产量构成因子以及产量,建立单株蒴果数、单蒴粒数、千粒重、单株产量与青枯病严重度的回归方程,在此基础上对芝麻青枯病严重度与单株产量损失率进行回归分析。结果表明:随着青枯病严重度上升,芝麻株高显著降低,空梢长度显著增长,始蒴高度显著增高;而芝麻单株蒴果数、单蒴粒数、千粒重均显著下降,其中芝麻单株蒴果数降低最显著,各级芝麻病株的单株蒴果数之间显著差异,且4个芝麻品种9级病株的单株蒴果数比0级病株降低71.24%~79.08%;各级病株的单株产量之间显著差异,4个芝麻品种的1、3、5、7和9级病株平均产量损失率分别为12.56%、29.53%、54.01%、72.57%和81.98%;青枯病严重度与单株蒴果数、单蒴粒数、千粒重3个产量构成因子呈极显著线性负相关;青枯病严重度x与产量损失率y的线性回归方程为y=2.5534+9.4132x(R~2=0.9867),说明青枯病严重度越高,损失率越大。  相似文献   

16.
不同氮水平下化学调控对旱地冬小麦生长及产量的影响   总被引:4,自引:0,他引:4  
通过田间试验研究了不同氮水平下分阶段采用多效唑及其与6-BA配合对小偃6号和小偃22两小麦品种生长及产量的影响.结果表明,多效唑浸种显著增加了小麦的单株分蘖,拔节初期喷施多效唑明显降低了两品种的株高.不同生长阶段使用生长调节物质均增加了两品种的叶面积和叶片叶绿素SPAD值,尤其以灌浆初期喷施6-BA后对成熟期叶片SPAD值的增加幅度最为突出,表明其具有延缓叶片衰老,延长叶片功能期的效果.采用多效唑及其与6-BA配合进行分阶段化学调控具有明显增产作用,其中多效唑与6-BA相结合处理较清水处理小麦产量提高了601.2 kg/hm2,增产幅度达显著水平;小麦穗粒数和千粒重的增加是其籽粒增产的主要原因.由此可见,在小麦生长的不同阶段采取不同的化控措施,可以有效地调节小麦生长发育,达到提高作物产量的目的.  相似文献   

17.
In an experiment conducted in a commercial glasshouse, tomato plants were grown in pots containing soils infested with a range of levels of Pyrenochaeta lycopersici in a randomized block design. There was found to be a negative correlation ( r = -0.93) between total yield in kg per plant (y) and % disease severity ( x ) recorded 8 weeks after planting when the disease data were exponentiated; the best fit was obtained by the equation v = 45.7–42.3 x 0.006 Fruit number was reduced by 0.2% for each 1% increase in the disease, but a stronger correlation was obtained by the equation y (fruit number) = 417–368 x 0.006
In a separate trial, the relationship between disease severity 8 weeks after planting and yield loss was shown to be affected by soil type. Early-season loss of potential yield was found to be lower in sandy soil than in peat and clay. By the end of the season, loss in total potential yield was greater in peat soil than in clay. The effect that soil conditions can have in modifying the relationship between disease severity and yield loss is discussed.  相似文献   

18.
花生褐斑病和网斑病田间混发流行过程及其产量损失研究   总被引:2,自引:1,他引:1  
 通过田间小区人工接种试验,分析比较了花生褐斑病和网斑病单独及混合发生的流行过程及对花生产量损失的影响。结果表明,在病害混发初期,病害间无明显的相关性,随着病情加重,病害间的负相关性逐渐增大并达到显著水平,说明病害间有明显的抑制作用。在不同生育期接种发病情况有所差异,在开花初期和盛花期接种,褐斑病和网斑病的病情较重,而在开花末期接种的病情较轻,但都能表现病害间的抑制作用。病害混发时造成的产量损失小于各病害单独造成损失之和,对白沙1016和四粒红接种2种病菌,病害混合发生所造成产量损失约为各病害单独引起损失之和的77.2% ~ 85.7%和76.1% ~ 79.6%。在不同生育期接种2种病菌,2个品种产量的损失均随着侵染时期的推迟而逐渐降低。  相似文献   

19.
通过田间试验初步研究采自上海市青浦区、浦东新区、嘉定区等地的籼型和偏籼型杂草稻以及采自崇明区的粳型杂草稻对水稻生长、产量构成因子和产量的影响。结果表明,在水稻营养生长期,不同籼型、偏籼型杂草稻密度对水稻基本苗、株高、单株鲜质量、分蘖数、倒二叶长、倒二叶宽均未有明显影响;而籼型和偏籼型杂草稻密度对产量构成因子有效穗数、穗长、一次枝梗数、穗粒数、千粒质量、结实率等均能产生一定影响,而粳型杂草稻只对水稻有效穗数、结实率、千粒质量等产生一定影响,实际产量等均随杂草稻密度的增加呈下降趋势。青浦区、浦东新区、嘉定区等地的籼型、偏籼型杂草稻和崇明区粳型杂草稻导致水稻产量损失50%时的密度分别为8.19、12.82、15.45、19.82株/m~2。  相似文献   

20.
黄淮冬麦区小麦品质性状与产量性状的关系研究   总被引:6,自引:0,他引:6  
以国家小麦区域试验参试品种为材料,研究了黄淮冬麦区小麦产量性状与品质性状的关系。研究表明:产量与容重、硬度、出粉率和面团流变学特性等品质性状无显著负相关性,因此,高产与上述品质性状可以较容易达到同步改良;产量与蛋白质含量和沉淀值多呈显著或极显著负相关性,提高产量可能会导致这些品质性状变劣,但在某些试验点和在某些品种中,它们无显著负相关性,甚至还表现出一定的正相关性;千粒重、穗粒数和穗粒重等产量性状与多数品质性状呈负相关,单株产量和单位面积穗数与多数品质性状呈正相关或极微弱的负相关,因此初步认为,在高产、优质育种中,侧重于单株产量和单位面积穗数的选择,有可能会协调高产与优质间的矛盾;面团流变学特性和产量性状间元显著矛盾性,较易同步改良。  相似文献   

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