The potential of using spectral reflectance indices to estimate yield in wheat grown under reduced irrigation
The potential of using spectral reflectance indices to estimate yield in wheat grown under reduced irrigation
复制标题
DOI：
10.1007/s10681-006-9104-9
复制
发表时间：
2006-07-01
期刊：
影响因子：
1.9
通讯作者：
Reynolds, M. P.
中科院分区：
文献类型：
--
作者：
Babar, M. A.;van Ginkel, M.;Reynolds, M. P.
本研究的目的是研究面包小麦的光谱反射指数（SRI）和籽粒产量之间的关联，估计其遗传力，并在减少灌溉条件下从SRI估计籽粒产量的相关选择反应（CR）。在孕穗期、抽穗期和灌浆期测量了小麦的反射率，并计算了归一化植被指数（NDVI）、简单比（SR）、水分指数（WI）、归一化水分指数-1（NWI-1）和归一化水分指数-2（NWI-2）。在三个不同的年份进行了三个田间试验（每个试验有30个先进品系）。建立了两种减少灌溉的环境：（1）一个灌溉水平（种植前），和（2）两个灌溉水平（种植前和孕穗期），两者都代表水分减少的水平。试验区灌水4-6次，一般可获得最高产量。所有SRI的基因型变异都是显著的。三个NIR（近红外辐射）为基础的指数（WI，NWI-1，和NWI-2）给出了最高水平的关联（表型和基因型）与粮食产量在两个减少灌溉环境。使用的平均SRI值平均在生长阶段和SRI从孕穗到灌浆的逐步整合增加了解释这些减少灌溉条件下的产量基因型之间的变化的能力。两次灌溉的广义遗传力（0.80）高于一次灌溉的广义遗传力（0.63）。总体而言，当NWI-2指数用作间接选择工具时，选择了50%至75%的12.5%最高产量基因型和50%至87%的25%最高产量基因型。强的遗传相关性，中度到高度的遗传力，相关的响应接近直接选择的粮食产量，和一个非常高的效率选择上级基因型表明，在育种计划中使用这三个SRI选择增加的遗传增益在减少灌溉条件下的粮食产量的潜力。
The objectives of this research were to study the association in bread wheat between spectral reflectance indices (SRIs) and grain yield, estimate their heritability, and correlated response to selection (CR) for grain yield estimated from SRIs under reduced irrigation conditions. Reflectance was measured at three different growth stages (booting, heading and grainfilling) and five SRIs were calculated, namely normalized difference vegetation index (NDVI), simple ratio (SR), water index (WI), normalized water index-1 (NWI-1), and normalized water index-2 (NWI-2). Three field experiments were conducted (each with 30 advanced lines) in three different years. Two reduced irrigation environments were created: (1) one-irrigation level (pre-planting), and (2) two-irrigation level (pre-planting and at booting stage), both representing levels of reduced moisture. Maximum yield levels in the experimental zone were generally obtained with 4-6 irrigations. Genotypic variations for all SRIs were significant. Three NIR (near infrared radiation) based indices (WI, NWI-1, and NWI-2) gave the highest level of association (both phenotypic and genotypic) with grain yield under both reduced irrigation environments. Use of the mean SRI values averaged over growth stages and the progressive integration of SRIs from booting to grainfilling increased the capacity to explain variation among genotypes for yield under these reduced irrigation conditions. A higher level of broad-sense heritability was found with the two-irrigation environment (0.80) than with the one-irrigation environment (0.63). Overall, 50% to 75% of the 12.5% highest yielding genotypes, and 50% to 87% of the 25% highest yielding genotypes were selected when the NWI-2 index was applied as an indirect selection tool. Strong genetic correlations, moderate to high heritability, a correlated response for grain yield close to direct selection for grain yield, and a very high efficiency of selecting superior genotypes indicate the potential of using these three SRIs in breeding programs for selecting increased genetic gains in grain yield under reduced irrigation conditions.