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1.
为探讨基于无人机RGB影像实现对小麦叶面积指数(leaf area index, LAI)和产量估算的可行性,设置不同生态点、品种和氮素处理的小麦田间试验,应用大疆精灵4 Pro无人机获取小麦拔节期、抽穗期、扬花期和灌浆期4个主要生育时期的RGB高时空分辨率影像,并同测定小麦LAI。采用相关性分析筛选出不同生育时期对LAI敏感的光谱与纹理特征集,并借助随机森林(random forest, RF)、偏最小二乘回归法(partial least squares regression, PLSR)、BP神经网络(back propagation neural network, BPNN)和支持向量机(support vector machine, SVM)分析方法,筛选出小麦不同生育时期最优的LAI估测模型。基于不同生育时期的光谱与纹理特征以及时期特征集,进一步建立产量预测模型,并在不同生态点验证叶面积估算模型与产量预测模型的普适性。结果表明,基于RF的LAI估测模型的验证精度最高,4个生育时期的均方根误差(root mean square error, RMSE)分别为2.26、1.44...  相似文献   

2.
郭涛  颜安  耿洪伟 《麦类作物学报》2020,40(9):1129-1140
为快速、准确地估测不同生育时期小麦品种(系)株高与叶面积指数(LAI)表型性状,基于各生育时期小麦品种(系)数字正射影像(digital orthophoto map,DOM)和数字表面模型(digital surface model,DSM),分别构建不同生育时期株高估测模型和光谱指数LAI估测模型。借助一元线性回归、多元逐步回归(SMLR)和偏最小二乘回归(PLSR)分析方法,并采用决定系数(r)、均方根误差(RMSE)和归一化均方根误差(nRMSE)综合性评价指标,筛选出小麦不同生育时期最优的株高和LAI估测模型。结果表明,(1)全生育期株高估测效果最好,模型预测值与实测值高度拟合(r、RMSE、nRMSE分别为0.87、5.90 cm、9.29%);在各生育时期中,灌浆期模型预测精度较好,成熟期预测精度最差,r分别为0.79和0.69。(2)所选的18种光谱指数与LAI相关性均较好,其中BGRI、RGBVI、NRI和NGRDI的相关系数达到极显著水平,且各时期三种回归估测模型均表现出较高的稳定性和拟合效果,其中SMLR回归模型对各生育时期LAI预测精度最好,其拔节期、孕穗期、扬花期、灌浆期和成熟期的预测集r分别为0.68、0.57、0.61、0.68和0.53。这说明,基于无人机获取的不同生育时期小麦DSM影像提取株高,并运用18种光谱指数构建LAI估测模型方法是可行的。  相似文献   

3.
通过哈尔滨地区15个无限结荚习性大豆品种顶荚形成初期的不同冠层叶面积指数(LAI)、不同冠层光截获(RLI)、全冠层光合生产率(RDMP)等光合生理生态性状对株荚数(NPP)、株粒数(NSP)、株粒重(SWP)、粒茎比(SSR)、主茎荚数(PMS)及主茎荚/节(PNMS)等产量性状多元回归方程集合的分析,明确该光合生理生态性状对此等产量性状形成效应及其对株型改良的影响。进而,在哈尔滨地区大豆生育期、结荚习性、叶形、种粒大小、化学品质及抗病虫性等生态类型的基础上,初步建立了哈尔滨地区亩产450斤左右的无限结荚习性大豆顶荚形成初期的理想株型优良冠层模式。试图为大豆理想株型育种提供一定科学依据。  相似文献   

4.
大豆叶面积指数的高光谱估算模型研究   总被引:1,自引:0,他引:1  
通过测试大豆4个生育阶段350~2500nm波段的冠层高光谱数据,用近红外波段760nm-850nm及红光波段650nm-670nm的2个范围内的波段反射率,组成了高光谱比值植被指数(RVI)和800nm和670nm2个波段反射率组成修改型二次土壤调节植被指数(MSAVI2);基于RVI和MSAVI2植被指数,建立了大豆叶面积指数(LAI)的6种单变量线性与非线性函数模型,经检验均达到1%极显著水平。其中,以RVI所构建洲的幂函数、MSAVI2所构建LAI的指数函数、对数函数估测模型的相关系数相对较高;用MSAVI2所构建的LAI精度较高的对数函数模型反演大豆叶面积指数,实测LAI与估测LAI呈极显著线性相关(R=0.9098^**,n=46),模型方程的估算精度达84.9%,实测值与估算值的RMSE=0.2420,平均相对误差为0.1510。表明采用高光谱植被指数,能够实时、无损、动态、定量提取大豆叶面积指数,为设计理想的大豆群体和大豆遥感估产提供了科学的依据。  相似文献   

5.
基于不同分析模型的大豆叶片SPAD值和LAI光谱估算比较   总被引:1,自引:0,他引:1  
为探讨在大豆鼓粒期采用光谱技术估算叶片SPAD值和LAI的有效分析模型和方法,本研究以大田鼓粒期大豆为试验材料,在3个不同时段9:45~10:15(10AM)、11:45~12:15(12PM)和13:45~14:15(2PM)测量冠层全波段光谱反射率,并分别使用极限学习机(ELM)、偏最小二乘回归(PLSR)、支持向量机(SVM)和随机森林(RF)构建大豆叶片SPAD值和LAI估算模型,并对比不同模型分析结果的估算精度。结果表明:在各模型中,12PM和2PM测定的光谱反射率与大豆叶片SPAD值和LAI的拟合精度均高于10AM。基于RF的大豆叶片SPAD值估算模型验证集的R2为0.910,RMSE为2.006,MRE为3.684;基于RF的大豆LAI估算模型验证集的R2为0.916,RMSE为0.209,MRE为4.383,与ELM、PLSR和SVM相比,有更高的估算精度。综上结果说明大豆鼓粒期在11:45~12:15和13:45~14:15采用RF模型,运用全波段的光谱反射率估算大豆叶片SPAD值和LAI可得到较准确的结果。  相似文献   

6.
为了建立冬油菜光合性状监测模型,实现油菜无损获取农作物信息,方便油菜生产过程中实时诊断、精确管理和估产,以甘蓝型冬油菜为试材,分析不同施肥量和密度条件下油菜冠层光谱与油菜净光合速率(Pn)、叶片叶绿素含量(SPAD)、叶面积指数(LAI)的定量关系,以获取最佳敏感波段的光谱指数;以最佳光谱指数为基础,建立冬油菜光合性状...  相似文献   

7.
为了对大豆全生育期光合特性进行系统研究,选用两个早期光合速率差异较大的大豆品种,测定真叶期(VC),三节期(V3)、五节期(V5)、始花期(R1)、初荚期(R3)、始粒期(R5)、鼓粒盛期(R6)、鼓粒盛期至始熟期中期(R6.5)、始熟期(R7)等9个生长时期大豆光合气体交换参数(光合速率Pn、气孔导度Gs、胞间CO2浓度Ci、蒸腾速率Tr和叶绿素含量等,测定了20份大豆材料V3和V9两个生育时期大豆光合气体交换参数,分析不同材料光合气体交换参数间变化关系。结果表明,在整个生育过程中,大豆于V3~R6时期间保持较高光合能力,且R6和R5期Pn值最高,SPAD值最大。R6期之后大豆Pn、Gs、Tr、SPAD迅速下降。20份大豆材料V3和V9期的Pn和Tr无显著相关性;Gs和Ci显著相关,相关系数分别为0.583和0.523。大豆产量同V3和V9期Pn值相关性均不显著,但同两个生育时期Pn值与全生育期乘积值显著相关,相关系数分别为0.561、0.612;同两生育时期Pn值均值与全生育期乘积(Pt)也呈显著正相关,相关系数为0.676。  相似文献   

8.
采用模拟试验方法,研究了棉田生态系统中有机无机肥配施对棉花产量及其构成因素、干物质积累和分配的影响。结果证明:(1)施用N肥能促进各生育时期拂株和各器官干物质积累、增加LAI、改善棉株农艺性状、极显著提高单位面积总铃数和棉花产量;(2)在等N、P、K条件下,与单施无机N相比,绿肥 沼肥 化肥配施对于提高棉花单位面积总铃数和产量、增加棉株和各器官干物量、促进不同生育时期棉株各器官干物量合理分配、使棉花生育后期保持最后LAI并降低LAI衰减速度效果较好,绿肥 化肥配施次之,单施无机N肥较差。  相似文献   

9.
盆栽试验条件下,以辽豆18为材料,分别在V2~R1,R1~R5,R5~R7期设置3个控水处理,控水结束后取样测定根系性状,成熟后测定产量。结果表明:干旱影响大豆产量的形成,干旱(W1)胁迫引起产量下降的程度要高于轻度干旱(W2)。不同时期干旱(W1)引起产量下降程度为:鼓粒期>花荚期>营养生长期。干旱胁迫(W1)主要通过降低大豆的单株荚数从而降低单株产量。大豆的根长比例和根表面积比例主要为根系直径为0~1.0 mm的细根,分别约占总根长的90%和总根表面积的60%。大豆根体积的分配比例主要是根系直径大于4.5 mm的粗根,其根体积所占比例在48%以上。R1~R5和R5~R7控水大豆细根(根系直径为0~1.0 mm)的根长和根表面积分配比例较V2~R1控水时增加。干旱降低了植株中直径大于4.5 mm粗根的根长比例、根表面积比例和根体积比例。随着生育进程的推进,根生物量密度逐渐增加,土壤干旱胁迫降低了根生物量密度。  相似文献   

10.
为实现基于可见光透射微分光谱的小麦植株含水量监测,通过三年田间试验,测定自拔节期以后小麦关键生育时期冠层透射光谱和植株含水量,确立了透射光谱微分参数与植株含水量间定量关系。结果表明,与小麦冠层原始透光率相比,一阶微分光谱能够很好地减轻生育时期的影响。将不同生育时期数据综合,不同波段的透射率与植株含水量相关性均较差,而微分光谱在439、735、823及950 nm处与植株含水量相关性较好(|r| 0.57),以735 nm处相关性最高。基于蓝光、黄光和红光波段筛选了21个光谱特征参数,其中红边振幅(Dr)、红蓝振幅归一化指数(Dr-Db)/(Dr+Db)、红边面积(SDr)、右峰面积(RSDR)、双峰面积比(RIDA)及双峰面积归一化指数(NDDA)6个光谱特征参数与植株含水量间相关性较好(r0.70)。在以上优选的光谱参数中,红边双峰面积比值(RIDA)及归一化指数(NDDA)与植株含水量的回归关系表现最好,拟合精度r~2大于0.69,均方根误差RMSE低于4.87,模型具有很好的稳定性,可以实时精确估测小麦植株含水量。这表明利用冠层透射微分光谱可对小麦植株含水量进行精确监测,对指导作物精确灌溉管理具有较大的应用潜力。  相似文献   

11.
随着早熟晚粳、中熟晚粳广泛种植,水稻轻型省力栽培方式旱直播的推广,病虫也发生了变化,成熟期显著推迟,下茬无法在适宜播期种植,影响粮食丰产稳产。提出筛选早熟当家品种、大力推广机插秧、加大粮食烘干设备的投入、合理施肥、精准植保等对策。  相似文献   

12.
概述了海峡两岸农业交流与合作的现状,提出了应该共同呼吁尽快实现两岸“三通”,开放农业生物技术图书期刊资料交流以及开放生物学科方面网络的思路,以便为农业交流与合作的顺畅开展打好基础,并寄希望能够就糖蔗、果蔗以及甘蔗笋等方面的研究与开发到台湾学习取经,开展学术交流或与台湾同行共同开展研究,为我省甘蔗业的发展作出贡献。  相似文献   

13.
Sorghum is a good source of phenolic compounds with a variety of genetically dependent types and levels including phenolic acids, flavonoids, and condensed tannins. Most sorghums do not contain condensed tannins, but all contain phenolic acids. Pigmented sorghums contain unique anthocyanins that could be potential food colorants. Some sorghums have a prominent pigmented testa that contains condensed tannins composed of flavan-3-ols with variable length. Flavan-3-ols of up to 8–10 units have been separated and quantitatively analyzed. These tannin sorghums are excellent antioxidants, which slow hydrolysis in foods, produce naturally dark-colored products and increase the dietary fiber levels of food products. Sorghums have high concentration of 3-deoxyanthocyanins (i.e. luteolinidin and apigenidin) that give stable pigments at high pH. Pigmented and tannin sorghum varieties have high antioxidant levels that are comparable to fruits and vegetables. Finger millet has tannins in some varieties that contain a red testa. There are limited data on the phenolic compounds in millets; only phenolic acids and flavones have been identified.  相似文献   

14.
Sorghum and millet phenols and antioxidants   总被引:5,自引:2,他引:5  
Sorghum is a good source of phenolic compounds with a variety of genetically dependent types and levels including phenolic acids, flavonoids, and condensed tannins. Most sorghums do not contain condensed tannins, but all contain phenolic acids. Pigmented sorghums contain unique anthocyanins that could be potential food colorants. Some sorghums have a prominent pigmented testa that contains condensed tannins composed of flavan-3-ols with variable length. Flavan-3-ols of up to 8–10 units have been separated and quantitatively analyzed. These tannin sorghums are excellent antioxidants, which slow hydrolysis in foods, produce naturally dark-colored products and increase the dietary fiber levels of food products. Sorghums have high concentration of 3-deoxyanthocyanins (i.e. luteolinidin and apigenidin) that give stable pigments at high pH. Pigmented and tannin sorghum varieties have high antioxidant levels that are comparable to fruits and vegetables. Finger millet has tannins in some varieties that contain a red testa. There are limited data on the phenolic compounds in millets; only phenolic acids and flavones have been identified.  相似文献   

15.
1大豆花叶病毒病 大豆病毒病(Soybean Mosaic Virus,SMV)是世界性病害之一。我国东北地区已鉴定的有5种,即大豆花叶病、顶枯病、蚕豆萎蔫病、南方菜豆花叶病、花生条纹病毒。其中大豆花叶病在全国大豆主要产区都有发生,十分常见。  相似文献   

16.
蔡红 《大豆科技》2001,(3):15-15
近年来,随着大豆播种面积的增长,受病虫危害日趋严重。特别是大豆根潜蝇(又名根明)与根腐病共同发生危害,严重影响大豆的生产。综合防治技术主要手段是三年以上轮作,适时播种及种衣剂拌种等措施。  相似文献   

17.
Summary Between 1993 and 1998 205 different potato cultivars and 1220 accessions/genotypes of wild and cultivated potato species from the IPK Genebank Gatersleben were evaluated. Parameters interesting for starch isolation and especially for the use of starch were determined. Altogether, there was a higher variability in wild potato species than in cultivated potatoes for all characteristics investigated: dry matter content, starch content, protein content, amylose content and mean particle diameter of starch granules.  相似文献   

18.
Yield and quality of winter and spring triticales for forage and grain   总被引:2,自引:0,他引:2  
In field experiments conducted over 2 years in Mediterranean conditions, five winter and five spring triticales were evaluated for forage and grain production in the same cropping season. The experiments had two treatments, namely harvesting for grain only, and dual-purpose forage and grain production. In the latter treatment, forage was cut when the first node was detectable (Zadoks' stage 31), without removing the apical meristems. Grain was harvested when ripe (Zadoks' stage 92) in both cut and uncut plots.
Environmental conditions affected grain production and protein content more than forage yield and quality. Winter triticales yielded about 43% more forage than spring types, but after forage removal the spring types yielded about 36% more grain than winter triticales.
Reductions in grain yield after clipping were more pronounced in winter (32%) than in spring (19%) types. Forage crude protein content was significantly higher in the spring types studied (24.6%) than in the winter types (23.5%), the opposite being true for fibre content (20.7 and 21.6% respectively). Grain crude protein content did not differ between grain and dual-purpose treatments, but was higher in the spring triticales (12.8%) than in the winter types (11.9%). There was more variability for the measured traits within the winter triticales studied than within the spring types.  相似文献   

19.
种子加工、检验理论与技术现状及思考   总被引:3,自引:0,他引:3  
种子加工及检验是种子向市场流通的关键,是商业化育种中赋予种子商品属性不可或缺的环节。种子加工、检验理论与技术的研究是完善种业产业链、实现规模化商业育种、夯实“育繁推一体化”种业科学的重要一环。中国的种业科学技术体系正在形成与完善之中,受制于行业发展水平,种子加工及检验理论与技术相对薄弱。本文回顾了种子加工及检验理论与技术研究发展历程,提出了完善中国种业科学发展的策略与建议。围绕种业发展的需要,在做好品种优质化繁育的基础上,分析种子加工及检验理论与技术的新方向和新需求,加强种业应用性研究,建立先进的种子质量检验体系,研制适合现代种业发展需求的种子加工设备,打造种子加工产业标准化生产体系,完善种业科学技术学科建设,促进种业产业持续健康发展。  相似文献   

20.
Summary

Arbuscular mycorrhizae were inoculated into phosphorus-deficient soil fertilized with either organic or chemical fertilizer with cucumber (Cucumis sativus L.) as the first crop and lettuce (Lactu-ca sativa L.) as the second crop but without additional fertilization and AM inoculation. AM increased dry matter and fruit yield of cucumber significantly in the unfertilized, organic-fertilized and P-deficient plants compared with the fully chemical-fertilized plants. AM inoculation increased the available phosphorus in plant and soil by around 30% for all treatments except for those chemically-fertilized. The rate of AM infection did not differ significantly among the fertilization treatments, but the infection intensity was higher in unfertilized, organic-fertilized and phosphorus-deficient treatments than chemical-fertilized treatment. The residual effects of AM-inoculated to cucumber were evident for lettuce in all pre-treatments that were unfertilized and un-inoculated for the second cropping. Without P-fertilization, neither crop could grow optimally even when the soil was inoculated with AM, suggesting that AM could not serve as a substitute for phosphorus fertilizer. However, the other beneficial effects of AM on crop growth and yield could not be fulfilled with phosphorus fertilizer.  相似文献   

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