Overhead supplemental far-red light stimulates tomato growth under intra-canopy lighting with LEDs

Far-red(FR) light regulates phytochrome-mediated morphological and physiological plant responses.This study aims to investigate how greenhouse tomato morphology and production response to different durations of FR light during daytime and at the end of day(EOD).High-wire tomato plants were grown under intra-canopy lighting consisting of red(peak wavelength at 640 nm) and blue(peak wavelength at 450 nm) light-emitting diodes(LEDs) with photosynthetic photon flux density(PPFD) of 144 μmol m–2 s–1 at 10 cm away from the lamps,and combined with overhead supplemental FR light(peak wavelength at 735 nm) with PPFD of 43 μmol m–2 s–1 at 20 cm below the lamps.Plants were exposed to three durations of FR supplemental lighting including: 06:00–18:00(FR12),18:00–19:30(EOD-FR1.5),18:00–18:30(EOD-FR0.5),and control that without supplemental FR light.The results showed that supplemental FR light significantly stimulated stem elongation thereby resulting in longer plants compared with the control.Moreover,FR light altered leaf morphology toward higher leaf length/width ratio and larger leaf area.The altered plant architecture in FR supplemented plants led to a more homogeneous light distribution inside the canopy.Total plant biomass was increased by 9–16% under supplemental FR light in comparison with control,which led to 7–12% increase in ripe fruit yield.Soluble sugar content of the ripe tomato fruit was slightly decreased by longer exposure of the plants to FR light.Dry matter partitioning to different plant organs were not substantially affected by the FR light treatments.No significant differences were observed among the three FR light treatments in plant morphology as well as yield and biomass production.We conclude that under intra-canopy lighting,overhead supplemental FR light stimulates tomato growth and production.And supplementary of EOD-FR0.5 is more favorable,as it consumes less electricity but induces similar effects on plant morphology and yield.

Far-red light: A regulator of plant morphology and photosynthetic capacity

Plant photosynthetic capacity directly determines crop yield. Light quality regulates photosynthetic capacity. This review discusses plant responses to far-red light from the phenotypic to the molecular level, focusing specifically on the improvement of photosynthetic capacity by adjustment of photosynthetic electron transport and the path of light energy. Far-red light can also regulate leaf angle and increase plant height and leaf area, via expression of associated genes, to capture more light energy.Thus, far-red light regulates plant morphology and photosynthetic capacity. Identifying the mechanism of this regulation may lead to increased crop yields.

Novel Cr^(3+)-activated far-red emitting phosphors withβ-Ca_(3)(PO_(4))_(2)-type structure for indoor plant cultivation

Cr^(3+)-activated far-red and near-infrared phosphors have drawn considerable attention owing to their adjustable emission wavelengths and wide applications.Herein,we reported a series of Cr^(3+)-doped phosphors withβ-Ca_(3)(PO_(4))_(2)-type structure,of which Ca_(9)Ga(PO_(4))_(7):Cr^(3+) possessed the highest far-red emission intensity.At an excitation of 440 nm,the Ca_(9)Ga(PO_(4))_(7):Cr^(3+) phosphors exhibited a broad emission band ranging from 650 to 850 nm and peaking at 735 nm,and the broadband superimposed two sharp lines centering at 690 and 698 nm.The optimal sample Ca_(9)Ga_(0.97)(PO_(4))_(7):0.03 Cr^(3+) had an internal quantum efficiency of 55.7%.The luminescence intensity of the Ca_(9)Ga_(0.97)(PO_(4))_(7):0.03 Cr^(3+) phosphor obtained at 423 K could maintain 68.5%of that at room temperature,demonstrating its outstanding luminescence thermal stability.A phosphor-conversion light-emitting diode was fabricated,indicating that the Ca_(9)Ga(PO_(4))_(7):Cr^(3+) phosphor has potential applications in indoor plant cultivation.

<i>Pinus taeda</i>cDNA Microarray as a Tool for Candidate Gene Identification for Local Red/Far-Red Light Adaptive Response in <i>Pinus sylvestris</i>

Light quality response is a vital environmental cue regulating plant development. Conifers, like angiosperms, respond to the changes in light quality including the level of red (R) and far-red (FR) light, which follows a latitudinal cline. R and FR wavelengths form a significant component of the entire plant life cycle, including the initial developmental stages such as seed germination, cotyledon expansion and hypocotyl elongation. With an aim to identify differentially expressed candidate genes, which would provide a clue regarding genes involved in the local adaptive response in Scots pine (Pinus sylvestris) with reference to red/far-red light;we performed a global expression analysis of Scots pine hypocotyls grown under two light treatments, continuous R (cR) and continuous FR (cFR) light;using Pinus taeda cDNA microarrays on bulked hypocotyl tissues from different individuals, which represented different genotypes. This experiment was performed with the seeds collected from northern part of Sweden (Ylinen, 68?N). Interestingly, gene expression pattern with reference to cryptochrome1, a blue light photoreceptor, was relatively high under cFR as compared to cR light treatment. Additionally, the microarray data analysis also revealed expression of 405 genes which was enhanced under cR light treatment;while the expression of 239 genes was enhanced under the cFR light treatment. Differentially expressed genes were re-annotated using Blast2GO tool. These results indicated that cR light acts as promoting factor whereas cFR antagonises the effect in most of the processes like C/N metabolism, photosynthesis and cell wall metabolism which is in accordance with former findings in Arabidopsis. We propose cryptochrome1 as a strong candidate gene to study the adaptive cline response under R and FR light in Scots pine as it shows a differential expression under the two light conditions.

Low temperature-mediated repression and far-red light-mediated induction determine morning FLOWERING LOCUS T expression levels

In order to flower in the appropriate season,plants monitor light and temperature changes and alter downstream pathways that regulate florigen genes such as Arabidopsis(Arabidopsis thaliana)FLOWERING LOCUS T(FT).In Arabidopsis,FT messenger RNA levels peak in the morning and evening under natural long-day conditions(LDs).However,the regulatory mechanisms governing morning FT induction remain poorly understood.The morning FT peak is absent in typical laboratory LDs characterized by high red:far-red light(R:FR)ratios and constant temperatures.Here,we demonstrate that ZEITLUPE(ZTL)interacts with the FT repressors TARGET OF EATs(TOEs),thereby repressing morning FT expression in natural environments.Under LDs with simulated sunlight(R:FR=1.0)and daily temperature cycles,which are natural LD-mimicking environmental conditions,FT transcript levels in the ztl mutant were high specifically in the morning,a pattern that was mirrored in the toe1 toe2 double mutant.Low night-to-morning temperatures increased the inhibitory effect of ZTL on morning FT expression by increasing ZTL protein levels early in the morning.Far-red light counteracted ZTL activity by decreasing its abundance(possibly via phytochrome A(phyA))while increasing GIGANTEA(GI)levels and negatively affecting the formation of the ZTL-GI complex in the morning.Therefore,the phyA-mediated high-irradiance response and GI play pivotal roles in morning FT induction.Our findings suggest that the delicate balance between low temperature-mediated ZTL activity and the far-red light-mediated functions of phyA and GI offers plants flexibility in fine-tuning their flowering time by controlling FT expression in the morning.

Stress responsive gene CIPK14 is involved in phytochrome A-mediated far-red light inhibition of greening in Arabidopsis

In this study, we show that CIPK14,a stress responsive CBL-interacting protein kinase gene,is involved in phytochrome A-mediated far-red light inhibition of greening in Arabidopsis seedlings. The CIPK14-impairment mutant cipk14 grown in continuous far-red (FR) light did not show greening when exposed to white light illumination for 15 h. By contrast, the FR-grown phytochrome A null mutant phyA greened within 0.5 h of exposure to white light. Although greening of Col-4 (wild-type) was not completely abolished by FR, it exhibited a significantly decreased greening capacity compared with that of phyA. Further analyses demonstrated that the expression of protochlorophyllide reductase (POR) genes was correlated with the greening ability of the genotypes. In addition, CIPK14 appeared to be regulated by both the circadian clock and PhyA. Taken together, these results suggest that CIPK14 plays a role in PhyA-mediated FR inhibition of seedling greening, and that a Ca-related kinase may be involved in a previously undefined branch point in the phytochrome A signaling pathway.

Specific tracking of monoamine oxidase A in heart failure models by a far-red fluorescent probe with an ultra large Stokes shift

Monoamine oxidase A(MAO-A) is a prominent myocardial source of reactive oxygen species(ROS), and its expression and activity are strongly increased in failing hearts. Therefore, accurate evaluation of MAOA activity in cardiomyocytes is of great importance for understanding its biological functions and early diagnosing the progression of heart failure. However, so far, there is no report on the fluorescent diagnosis of heart failure by a specific probe for MAO-A. In this work, two far-red emissive fluorescent turn-on probes(KXS-M1 and KXS-M2) for the highly selective and sensitive detection of MAO-A were fabricated.Both probes exhibit good response to MAO-A, one of which, KXS-M2, performs better than the other one in terms of a fluorescence increment and sensitivity. Using the pioneering probe KXS-M2, specific fluorescence imaging of MAO-A in glucose-deprived H9c2 cardiac cells, zebrafish and isoprenaline-induced failing heart tissues was achieved, proving that KXS-M2 can serve as a powerful tool for the diagnosis and treatment of heart failure.

远红光阶段辐照对水稻幼苗生长及水分利用效率的影响

以水稻“绿旱639”为研究对象,在水稻种期(T_(1)处理)、芽期(T_(2)处理)和苗期(T_(3)处理)分别进行远红光辐照,并设置对照组(CK处理)。测算了水稻幼苗的生理指标、生长特性及水分利用效率,研究了阶段辐照下远红光对水稻幼苗生长及水分利用效率的影响。结果表明,种期进行辐照水稻幼苗的叶面积比芽期和苗期分别增加了15.82%和20.46%;芽期进行辐照水稻幼苗的相对生长速率比种期和苗期分别增加了23.10%和37.01%,根长、根冠比、净同化速率等指标的增长幅度均大于种期和苗期辐照;苗期进行辐照水稻幼苗的叶片水分利用效率与种期和芽期辐照相比,分别增加了16.60%和23.07%。综上,在水稻幼苗的芽期进行远红光辐照,可以有效促进水稻幼苗的生长;在水稻幼苗的苗期进行远红光辐照,可以显著提高水稻幼苗的水分利用效率。研究结果从光学农业角度为提高水稻及其他作物水分利用效率提供了参考。

不同光质对草莓叶片光合作用和叶绿素荧光的影响

不同光质下草莓叶片的叶绿素含量、Fv/Fm、Fm/Fo、PSⅡ无活性反应中心数量和QA的还原速率与不同光质中的红光/蓝光比值呈正相关,而叶绿素a/b比值与红光/蓝光比值呈负相关。不同光质下草莓叶片类胡萝卜素的含量蓝膜>绿膜>红膜、白色膜、黄膜,与红光/远红光(R/FR)呈负相关。不同光质对草莓叶片的表观量子效率、羧化效率及光呼吸速率影响较大。除绿膜下草莓叶片的净光合速率较低外,其它膜下草莓叶片的净光合速率均无明显差异。

不同光质对丰香草莓生长发育的影响

研究了相同光强下不同光质对丰香草莓生长发育的影响。结果表明,不同光质膜处理对草莓的生长结果、干物质分配和果实品质均有影响。与中性膜相比,绿膜和红膜下草莓植株的叶柄长度和叶面积显著增加,而蓝膜的叶柄长度和叶面积明显较低。光质不同也影响草莓干物质的分配,干物质向叶片和叶柄分配比例绿膜最高,蓝膜最低,其它膜之间相近。而干物质向果实、冠状茎和根系中的分配比例均以蓝膜最高,其次为红膜,绿膜最低,黄膜与中性膜相近。红膜下生长的草莓,产量最高、果实最大;蓝膜下可溶性固形物含量、抗坏血酸含量和固酸比最高;而绿膜下则产量最低、果实最小、可溶性固形物含量和固酸比最低。抗坏血酸含量的高低与不同膜中的紫外和蓝紫光的比例一致,与红光/蓝光比值相反。

暗前适宜LED远红光光照强度促进设施番茄种苗生长发育

为了研究LED光源在设施番茄育苗生产上的精准化利用。该试验以金鹏1号番茄植株为试材,研究了进入黑暗前LED远红光处理对番茄植株形态、激素含量、光合速率和矿质元素含量的影响。结果表明,当番茄植株进入黑暗前进行10 min远红光处理,番茄植株的株高及茎的鲜质量发生了明显变化,番茄植株的株高和茎的鲜质量随着远红光光照强度的增加而增加,当远红光的光照强度增加到10μmol/(m^2·s)时番茄植株的株高和茎的鲜质量也达到了最大值。与对照相比,进入黑暗前进行时长10 min,光照强度为10μmol/(m^2·s)的远红光处理后番茄植株叶片中的生长素和赤霉素3的含量显著上升;叶绿素和净光合速率显著降低;番茄植株茎中N含量显著降低,叶中P含量显著降低,K含量显著升高,根系中的N、P、K含量都显著增加。因此,可以通过调控黑暗前远红光的光照强度来精确调控番茄植株的株高,控制番茄的生长。

设施环境中红光与远红光比值调控的研究进展

该文详述了近年来国内外设施园艺环境中R/FR比值对植物形态、生长发育的影响以及实验、生产中R/FR比值调控方法的研究进展。介绍了几种人工光源及光质调控薄膜的R/FR特性,对进一步开展此项研究工作提出建议。

暗期红光、远红光间断处理对小麦叶片细胞壁成分的影响

在短日照长暗期条件下的暗期，对小麦华麦８号幼苗给予红光、远红光间断处理，研究不同光质对小麦细胞壁成分的影响，结果表明，红光间断处理细胞壁木质素含量增加，远红光处理的则下降；红光与远红光处理的叶片细胞壁纤维素含量虽无明显差异，但红光处理的细胞壁抗纤维素酶水解能力下降，远红光处理的抗纤维素酶水解能力则增强。

W6154s类型水稻在光敏、温敏分类问题上的商讨

光敏核不育水稻农垦５８ｓ的光敏不育基因转入籼稻遗传背景后产生的籼型不育系保持了明显的育性转换特性，但其育性转换对温度的变化变得非常敏感，Ｗ６１５４ｓ就是这类新不育系的典型代表。经数年研究证明：Ｗ６１５４ｓ存在一定的光敏温度范围，在此温度范围内具有明显的育性第二光周期反应，其育性变化温度敏感期与光敏感期有部分重叠，在长暗期进行红光闪光间断能有效地诱导花粉育性降低，并且这种效应能被远红光所逆转，温敏不育系的育性转换过程中则没有这些光周期诱导效应。籼型遗传背景只是影响了光敏不育性的表达条件，没有改变其对光周期反应的基本性质，Ｗ６１５４ｓ仍为一种育性感温性强的光敏不育系，不能简单地将之划分为温敏不育系。

特征远红外技术用于果蔬干制的研究

特征远红外装置是一种具有在50℃温度下工作的新型的脱水设备。本实验是利用此装置对大葱、菠菜、香菜、黄瓜、胡萝卜、苹果、梨、葡萄、哈蜜瓜等9种果蔬进行脱水干燥并研究其干燥特点。

远红光对生菜光合作用及叶绿素荧光特性的影响

以植物工厂中水培生菜为试验对象,白光LED光源处理作为对照,在对照基础上添加不同光照度的远红光设置FR1处理[添加10μmol/(m^(2)·s)远红光]和FR2处理[添加20μmol/(m^(2)·s)远红光],研究不同远红光光照度对生菜生长、光合作用及叶绿素荧光特性的影响。结果表明:与对照相比,FR1处理显著提高了生菜株高、最大叶面积、根系长度及干鲜质量;FR2处理的株高、根系长度与对照间差异不显著,且生菜干鲜质量随着远红光照度的增加呈增长变缓趋势。FR2、FR1处理均显著降低了叶片净光合速率,但同时提高了光饱和点及降低了暗呼吸速率,有利于生菜干物质的累积。远红光处理增加了单位面积活性反应中心数量,增加了吸收与捕获的光能;随着远红光强度的增加,FR2处理的PSⅡ供体侧放氧复合体(OEC)遭受严重破坏,用于电子传递的能量显著降低,即吸收的光能用于光化学反应的比例降低;且FR2处理用于热耗散的能量比例显著大于FR1处理。综上所述,在白光LED上添加10μmol/(m^(2)·s)远红光可提高生菜产量。

不同红光远红光配比对冰草生长发育、光合特性及品质的影响

为探明人工光植物工厂中红光远红光配比对水培冰草产量和品质的影响,本研究在光合有效辐射强度200μmol·m^(-2)·s^(-1)的条件下,以白光LED作为CK(R/FR=5.5),在CK基础上添加不同强度远红光,分别设置FR1(R/FR=1.2)和FR2(R/FR=0.8),研究不同光质组合处理下冰草的生长发育、光合特性及营养品质等指标的变化。结果表明,与CK相比,FR2和FR1的株高分别显著增加32.59%和20.70%,叶面积分别显著增加162.68%和47.33%;FR2的地上部鲜、干质量分别显著增加52.08%和63.66%。FR2和FR1降低了叶片叶绿素含量、叶绿素a/b值及净光合速率,但提高了冰草对弱光的利用能力。低R/FR值对冰草各品质指标有不同程度影响,FR2和FR1的叶片类胡萝卜素较CK分别显著下降27.08%和34.62%;FR2的叶片可溶性糖、可溶性蛋白及维生素C含量较CK分别显著增加23.86%、27.48%和17.73%。FR2和FR1显著增加了冰草中酮类及酯类挥发性物质含量,并显著降低了冰草叶片的硝酸盐含量。综上,植物工厂中白光LED基础上添加远红光设置R/FR值为0.8,可有效提高水培冰草的产量、维生素C、可溶性糖和挥发性酮类及酯类物质含量。本研究为远红光在植物工厂中的应用提供了参考。

红光和红外线辅助伤口治疗的照射时间与效果观察

目的近年来已有关于物理干预辅助治疗伤口以减轻疼痛与促进愈合的研究,但尚缺乏不同光源物理干预治疗的时间与效果研究。文中旨在比较红光（red light,RL）照射与远红外线（far infrared ray,FIR）照射2种物理干预辅助伤口治疗的效果及有效作用时间。方法将90例伤口患者按照随机数字表法分为3组（n=30）,3组伤口的处理方法除物理干预方法与时间外均相同,分别为RL治疗20 min（RL20组）、FIR治疗10 min（FIR组）和RL治疗10 min（RL10组）。治疗前后7、14、21和28 d分别测量伤口温度、疼痛计分、伤口面积并计算每组伤口的缩小率和治愈率,记录愈合时间。结果 3组伤口治愈率差异无统计学意义（χ2=0.71,P〉0.05）,平均愈合时间差异无统计学意义（F=0.31,P〉0.05）。治疗28 d后伤口缩小率均〉50%,提升伤口温度1~2℃。3组伤口患者治疗前后第7-28天疼痛计分减少均≥6分,组内比较差异有显著性统计学意义（P〈0.01）,但组间比较差异无统计学意义（P〉0.05）。RL20组治疗第28天伤口面积明显缩小（P〈0.01）,FIR组第14、28天伤口缩小明显（P〈0.05）。RL10组第21、28天缩小明显（P〈0.05）。结论 RL与FIR辅助伤口治疗效果相当,但RL治疗具有照射均匀、穿透深度深、操作方便、安全性强等优点;照射10 min和20 min的效果相近。建议RL辅助治疗伤口每次10 min、连续14 d为宜。FIR治疗以热辐射效应为主,照射时间10 min/次、疗程根据伤口可延长14 d以上。

红光与远红光对农垦58S花粉育性的逆转性

研究表明,农垦58S的育性主要受光周期控制:在暗期进行白光中断处理也能起到长日诱导不育的效应;光信号在体内不传导;朱英国等首先提出可能光敏色素参与了农垦58S的育性转换的调控。为了证实光敏色素在HPGMR育性转换过程中的作用,利用光敏色素具有红光/远红光逆转特性,我们在1987～1989年连续三年研究红光和远红光对农垦58S的花粉育性的诱导效应。本文将报道其主要结果。

远红外Hg^(2+)荧光探针的研制及其在生物成像中的应用

基于Hg^(2+)诱导罗丹明内硫酯"关-开"环原理,设计合成了一种简便的罗丹明101内硫酯(1)荧光探针分子并用于环境水样中汞离子的定量检测及活细胞内汞离子荧光成像检测.结果表明:在测试体系中加入汞离子,探针分子1(10μmol/L)溶液荧光显著增强,当加入等当量的汞离子时,溶液的荧光强度增强了68倍,溶液的颜色也从无色变为了粉红色;探针分子1(10μmol/L)对0.1~10μmol/L浓度范围内的汞离子响应呈线性关系,R2=0.994 9,检出限为0.04μmol/L.选择性和竞争性实验结果表明:探针分子1对汞离子有较高的选择性和较高的灵敏度;探针分子1可成功用于细胞内汞离子的荧光成像可视化检测.