单色光对小麦草生长速率的影响研究

通过LED光照实验,探究不同光质和光周期对小麦草生长速率的影响。采用大功率红、蓝LED灯,红光峰值波长为655 nm,蓝光峰值波长为438 nm。实验采用控制变量法,以光质和光周期为变量,其余生长环境保持一致。结果表明:红光照射下生长速率要明显优于蓝光,甚至超过室内日光。在红蓝复合光中,红光光强高于蓝光时,更利于小麦草生长;连续24 h的光照与间隔12 h的光照相比,略有生长优势。     

蓝光LED对台湾金线莲生长及生理指标的影响

以台湾金线莲Anoectochilus formosanus为材料,考察445、465、485 nm等3种波长蓝光LED对其生长及黄酮含量的影响。结果显示,445和465 nm处理显著提高台湾金线莲鲜质量、根系活力和叶绿素a/b比值,促进可溶性糖、可溶性蛋白及黄酮累积。其中,445 nm处理组的可溶性蛋白比对照组提高33.52%,465 nm处理组的可溶性糖比对照组提高12.77%,465 nm处理的黄酮含量为18.23 mg·g-1,比对照组提高34.54%。生产上可采用波长445或465 nm 的LED作为独立或组合光源,以提高金线莲种植品质。     

不同波长LED光源对韭菜迟眼蕈蚊生殖行为的影响

【目的】明确不同波长的LED光源对韭菜迟眼蕈蚊Bradysia odoriphaga Yang et Zhang求偶、交配及繁殖等生殖行为的影响。【方法】采用红(625~630 nm)、橙(600~605 nm)、黄(590~595nm)、绿(525~530 nm)、蓝(455~460 nm)和白(6 000~6 500 k)6种LED光源在韭菜迟眼蕈蚊成虫交配期进行照光处理,观察统计其求偶和交配行为以及单雌产卵量、卵孵化情况和有效后代数量。【结果】韭菜迟眼蕈蚊成虫求偶前期时长在橙光下最长,为28.48 min。求偶率在蓝光下最高,为86%;橙光下最低,为48%。交配期时长在蓝光下最长,为4.59 min;橙光下较短,为4.23 min。单雌产卵量在各波长光源下与对照均无显著差异。卵孵化率在蓝光下最低,仅为43.41%。有效后代数量在蓝光下最低,仅为27.00头;橙光下次之,为43.40头。【结论】LED光源的波长可影响韭菜迟眼蕈蚊的生殖行为,其中橙光(600~605 nm)不利于其求偶、交配和繁殖;蓝光(455~460nm)虽有利于其求偶和交配,但明显抑制其繁殖。     

单色光对小麦草营养成分的影响

以小麦草为研究对象,通过LED光照实验,探究不同光质对小麦草营养品质指标(叶绿素含量,可溶性蛋白含量,可溶性糖含量,超氧化物歧化酶(SOD)活性,总酸度,脯氨酸含量)的影响。采用与小麦草光合作用吸收光谱吻合的大功率红、蓝LED灯,红光峰值波长为655 nm,蓝光峰值波长为438 nm,带宽均为30 nm左右,对小麦萌发后幼苗进行为期10天的实验室光照培养箱培养,与日光培养对照,然后测定营养品质指标。除光质为变量外,保持其余生长环境一致,实验结果表明:红光有利于提高小麦草叶绿素含量、可溶性糖含量和SOD活性;蓝光有利于提高可溶性蛋白含量、总酸度含量和脯氨酸含量。通过红光和蓝光照射,有利于改善小麦草的营养品质。     

光照对螺旋藻生长速率的影响

螺旋藻是一种经济价值很高的微藻。针对螺旋藻的高光效性,在不同波长LED灯照射下,研究光照对螺旋藻生长速率的影响。结果表明,在螺旋藻的养殖中,经过红光(650-675 nm)、绿光(522-532 nm)和蓝光(465-475 nm)处理后,获得最大螺旋藻的干物质含量分别为1.232 g/L、1.195 g/L、0.742 g/L;红光处理过的螺旋藻生长速度最快,所得的干物质含量比对照样增加了66.04%。     

光质与补光对水稻幼苗生长及光合速率的影响

测定水稻成龄离体叶片在波长380～800nm下的透射率,推算其吸收光谱;在培养室内,观测水稻幼苗在蓝(475±5nm)、黄(585±5nm)、红(660±5nm)色的半导体(LED)和普通日光灯下的生长状况,每天照光12h;同时,在大棚中将刚萌发的水稻幼苗白天自然日照,每晚(18:00～24:00)人工补蓝、红、黄、白光各0、2、4、6h,定期观测其生长情况,在补光50d后测成龄叶片的光合曲线。结果发现:水稻叶片在波长400～500nm之间及680nm附近有较强吸收;在不同光质下进行培养,单波蓝光对水稻幼苗的生长最好;补光对水稻幼苗生长均有促进作用,其中补白光4h效果最明显,其次是补黄光2h;补蓝光2、4h和补白光4h提高植株的光合能力。     

荔枝蒂蛀虫成虫对LED光的趋性及其繁殖响应特征

为明确荔枝蒂蛀虫Conopomorpha sinensis成虫对不同LED光的趋性行为反应,初步筛选出该虫趋光性不同的光色并进一步研究其对成虫繁殖生物学特性的影响,以期为今后研发特异性强且绿色高效的荔枝蒂蛀虫灯光防控技术提供理论依据.本文采用对比实验法,测试了荔枝蒂蛀虫雌蛾对9种供试光源的趋性行为反应,并进一步研究夜间LED光照射对荔枝蒂蛀虫成虫交配率、繁殖力及寿命的影响.结果显示,荔枝蒂蛀虫雌成虫对不同LED光的趋光反应率由高到低为:蓝(445～450 nm)>紫(400～405 nm)>红(655～665 nm)>蓝绿(475～480 nm)>橙(600～605 nm)>绿(515～520 nm)>黄(570～575 nm)>白(400～700 nm)>黑暗>紫外(365 nm),试虫对紫外光表现出明显的避光性,对7种单色光表现为不同程度的趋光性,其中对黄光和白光的趋光率在50％以下.在繁殖生物学方面,夜间50 lx的LED黄光和白光持续照射能使荔枝蒂蛀虫成虫的交配率由93.75％降低至50％以下,且产卵前期延长,雌蛾产卵量显著降低.此外,夜间不同LED光源照射能抑制已交配荔枝蒂蛀虫雌蛾产卵活动,白光照射组的单雌日均产卵量降低程度最大,为50.71％,黄光次之(48.96％),蓝光最小,为38.06％.综上所述,荔枝蒂蛀虫雌蛾对LED白光和黄光的趋光性较弱,夜间适当的LED白光(400～700 nm)和黄光(570～575 nm)持续照射可有效降低成虫交配率和繁殖力,该结果对促进LED白光干扰防控荔枝蒂蛀虫技术的优化升级具有一定指导意义.     

不同光环境对粘虫生长发育的影响

【目的】研究不同光环境条件对粘虫Mythimna separata生长发育存活的影响,探讨影响粘虫生存的关键光环境因子,揭示昆虫对光环境的适应能力,为粘虫发生分布情况进行准确预测提供实验依据。【方法】选取特定波长和光强的LED灯作为供试光源,以不同发育阶段粘虫为供试昆虫,测定10种供试光源条件下粘虫各发育阶段的存活与发育情况。【结果】365nm波长光源照射能显著降低粘虫卵孵化率,比对照组卵孵化率降低了50.33%;420 nm波长光源照射能显著降低粘虫幼虫存活率、幼虫化蛹率和蛹羽化率,且能延长幼虫期和蛹期,比对照组幼虫存活率、化蛹率和蛹羽化率分别降低了72.00%、65.67%和72.87%,比对照组幼虫期和蛹期分别延长了12 d和11.4 d;420 nm和460 nm波长光源照射能显著降低粘虫成虫存活率,比对照组成虫存活率分别降低了44.44%%和40.00%。【结论】光强1000lx,波长365、420、460 nm的光环境能够抑制粘虫的生长发育,不利于粘虫生存。     

高产杂交稻两优培九旱育秧苗期抗氧化系统活性的研究

以汕优63为对照,研究了旱育条件下两优培九幼苗的体内抗氧化系统的特性。显示两优培九在旱育条件下其体内三大抗氧化酶SOD、POD和CAT活性都较水育条件下高,而体内超氧阴离子含量和MDA含量和水育秧相比却没有大的差异;旱育条件下秧苗叶片内积累的脯氨酸量显著高于水育秧。这不但能提高水稻苗期抗旱能力,同时也为移栽大田后具有明显的生长优势和抗胁迫能力打下了物质基础。另外,发现秧苗培育时间过长也不利于获得高质量的秧苗,时间以30 d左右为宜。和汕优63相比,相同条件下的两优培九幼苗抗氧化系统活性较高,这也可能是两优培九高产的生理基础之一。     

不同波长光源对新蚜虫疠霉产孢能力的影响及霉菌蓝光受体基因的克隆和表达分析

光在调控真菌的多种生理过程中发挥着重要作用。为探究光照对新蚜虫疠霉Pandora neoaphidis产孢的影响,本文研究了不同波长光源(蓝光、绿光、白光、红光、黄光)和无光黑暗条件对新蚜虫疠霉分生孢子弹射能力的影响,通过cDNA末端的快速扩增(RACE)对新蚜虫疠霉的蓝光受体蛋白基因pnwc-1进行克隆并对其进行生物信息学分析,利用qRT-PCR对蓝光光源不同照射时长下pnwc-1的表达量进行了定量分析。结果表明,蓝色光源(波长460–465nm)照射后的新蚜虫疠霉菌丝产生的分生孢子数量显著高于其他波长光源,排序为:蓝光>绿光>白光>红光>黄光>无光。另外,分析克隆获得的全长为2 423bp的pnwc-1基因发现,其编码的蛋白具有蓝光受体蛋白典型的保守结构域,同源比对结果显示新蚜虫疠霉与接合菌门真菌归为一类但相对独立。qRT-PCR的定量分析结果表明随着照射时长增加,蓝光处理能显著提高pnwc-1的表达量,而且pnwc-1的相对表达量与累积产孢量存在正相关(R2=0.9798)。本研究为后续蓝光及其受体基因功能的深入研究提供了实验基础,并促进以新蚜虫疠霉为代表的虫霉目真菌在害虫生物防治中的应用。     

不同比例红蓝光对番茄幼苗生长和光合作用的影响

为了探索番茄幼苗生长发育对红蓝组合光的响应机制,本试验采用发光二极管(LED)精量调制光源,以番茄品种‘SV0313TG’为试材,设红光(R)、蓝光(B)和红蓝组合光(9R1B、6R1B、3R1B、1R1B、1R3B)7个处理,以白光为对照,研究不同比例红蓝光质对番茄幼苗生长、光合色素含量、光合特性、叶绿素荧光参数及根系活力的影响.结果表明:不同比例红蓝光质处理对番茄幼苗生长的影响具有明显差异.红光显著促进幼苗株高增加,比叶面积增大,胞间CO₂浓度提高,但PSⅡ最大光化学效率(F_v/F_m)、PSⅡ实际光化学效率(Ф_PSⅡ)降低,根系生长受阻,根系活力下降,壮苗指数降低;蓝光下幼苗生长受到明显抑制,叶绿素含量降低,但叶绿素a/b 值升高;红蓝组合光有利于番茄幼苗的生长发育,3R1B处理下植株干物质量、叶绿素含量和光合性能均显著提高,幼苗生长健壮,壮苗指数最大.综上,红蓝组合光能够增加番茄幼苗叶片光合色素含量,提高光合效率,促进植株生长,尤以3R1B处理最佳.     

不同育秧方式和插植密度下华南双季晚籼稻根系活力的初步研究

本试验于1995年晚季初步研究了水、旱育秧方式和不同插植密度下根系活力的变化趋势及与地上部生长发育的关系。结果表明:(1)旱育秧苗根系活力明显高于水育秧,根系活力与白根数、地上部苗体干/鲜重比值呈显著正相关,与褐根数、苗高、叶龄和百苗干、鲜物重呈负相关。(2)旱育单苗移植处理的根系活力在水稻整个生育过程中均高于旱育多苗移植处理,水秧单苗和多苗移植处理。生育后期根系活力与主茎功能叶片叶绿素含量和叶面积系数分别呈极显著正相关和正相关,旱育秧苗的这些特性有利于移植后叶片与分蘖的快速形成及生育后期延缓叶片衰老,提高籽粒充实度。同时提出,在水肥管理上应适当加大后期穗肥比例,改善光照条件和土壤的通气排水状况,以便充分发挥旱育稀植秧苗的增产优势。     

LED光源对不同品种生菜生长和品质的影响

以自然光为对照(CK),探讨了LED红光(R)、蓝光(B)和红蓝组合光(RB)对不同品种生菜生长与品质的影响.结果显示:(1)不同光质处理的4个品种生菜的根长、株高及生物量积累等形态及生长指标具有相同的变化规律.(2)植株干鲜重、叶面积及根系活力在R和RB处理下都较大,而在B处理下较小;金祥、高华和永荣的B处理植株可溶性蛋白含量较高;联记、金祥和高华植株的淀粉含量在RB处理下较多,而永荣在R处理下较多;各品种植株可溶性糖含量在R和RB处理下较高,而永荣植株RB处理蔗糖含量较高,其余品种蔗糖含量在R处理下较高;金祥、高华和永荣VC含量在B和RB下较高,联记在RB下较高,各品种在R下均较低;植株总酚含量在各光质处理间无显著差异.(3)联记的硝态氮含量及亚硝酸还原酶对光质敏感,B处理能降低其硝态氮含量及亚硝酸还原酶活性,其他品种的硝态氮含量及亚硝酸还原酶活性在光质处理间无显著差异.研究表明,相同光质下品种间生长无显著差异,而各品种生菜植株在红光和红蓝组合光下生长较好,在红蓝光处理下品质较优,红蓝光是设施栽培生菜的良好光源.     

The Novel Approach to Enhance Seed Security: Dual Anti-Counterfeiting Methods Applied on Tobacco Pelleted Seeds

Seed security is of prime importance for agriculture. To protect true seeds from being faked, more secure dual anti-counterfeiting technologies for tobacco (Nicotiana tabacum L.) pelleted seed were developed in this paper. Fluorescein (FR), rhodamine B (RB), and magnetic powder (MP) were used as anti-counterfeiting labels. According to their different properties and the special seed pelleting process, four dual-labeling treatments were conducted for two tobacco varieties, MS Yunyan85 (MSYY85) and Honghua Dajinyuan (HHDJY). Then the seed germination and seedling growth status were investigated, and the fluorescence in cracked pellets and developing seedlings was observed under different excitation lights. The results showed that FR, RB, and MP had no negative effects on the germination, seedling growth, and MDA content of the pelleted seeds, and even some treatments significantly enhanced seedling dry weight, vigor index, and shoot height in MS YY85, and increased SOD activity and chlorophyll content in HHDJY as compared to the control. In addition, the cotyledon tip of seedlings treated with FR and MP together represented bright green fluorescence under illumination of blue light (478 nm). And the seedling cotyledon vein treated with RB and MP together showed red fluorescence under green light (546 nm). All seeds pelleted with magnetic powder of proper concentration could be attracted by a magnet. Thus, it indicated that those new dual-labeling methods that fluorescent compound and magnetic powder simultaneously applied in the same seed pellets definitely improved anti-counterfeiting technology and enhanced the seed security. This technology will ensure that high quality seed will be used in the crop production.     

Growth and photosynthesis of Chinese cabbage plants grown under light-emitting diode-based light source

We compared growth and the content of sugar, protein, and photosynthetic pigments, as well as chlorophyll fluorescence parameters in 15- and 27-day-old Chinese cabbage (Brassica chinensis L.) plants grown under a high-pressure sodium (HPS) lamps or a light source built on the basis of red (650 nm) and blue (470 nm) light-emitting diodes (LEDs) with a red to blue photon ratio of 7: 1. One group of plants was grown at a photosynthetic photon flux (PPF) level of 391 ± 24 μ mol/(m² s) (normal level); the other, at a PPF level of 107 ± 9 μ mol/(m² s) (low light). Plants of the third group were firstly grown at the low light and then (on the 12th day) transferred to the normal level. When grown at the normal PPF level, the plants grown under LEDs didn’t differ from plants grown under HPS lamps in shoot fresh weight, but they showed a lower root fresh and dry weights and the lower content of total sugar and sugar reserves in the leaves. No differences in the pigment content and photosystem II quantum yield were found; however, a higher Chl a/b ratio in plants grown under LEDs indicates a different proportion of functional complexes in thylakoid membranes. The response to low light conditions was mostly the same in plants grown under HPS lamps and LEDs; however, LED plants showed a lower growth rate and a higher nonphotochemical fluorescence quenching. In the case of the altered PPF level during growth, the plant photosynthetic apparatus adapted to new conditions of illumination within three days. Plants grown under HPS lamps at a constant normal PPF level and those transferred to the normal PPF level on the 12th day, on the 27th day didn’t differ in shoot fresh weight, but in plants grown under LEDs, the differences were considerable. Our results show that LED-based light sources can be used for plant growing. At the same time, some specific properties of plant photosynthesis and growth under these conditions of illumination were found.     

Tree seedling response to LED spectra: implications for forest restoration

We found that different spectra, provided by light-emitting diodes or a fluorescent lamp, caused different photomorphological responses depending on tree seedling type (coniferous or broad-leaved), species, seedling development stage, and seedling fraction (shoot or root). For two conifers (Picea abies and Pinus sylvestris) soon after germination (≤40 days), more seedling growth was related to a lower ratio of red-to-far-red (R:FR) light. As growth continued to 120 days, spectra with a greater complement of blue light yielded more growth. Roots showed more plasticity to light spectra than shoots. In general for the evergreen broad-leaved Quercus ilex, spectra with additional R:FR than for conifers yielded more growth in the first 57 days. Subsequently as seedlings grew, shoot growth appeared to be influenced less by light source than roots, with root length showing the greatest responses. Our results suggest that manipulating light spectra to foster desired seedling traits may be another tool for use in the production of high-quality seedlings as defined through the Target Plant Concept. Such seedlings are needed for restoration of the two billion hectares of degraded forestland, especially on harsh sites such as those found in the Mediterranean region, and to sequester carbon to mitigate climate change.     

不同光质对桑树幼苗生长和光合特性的影响

光质可影响植物光合特性、形态以及生理过程。本试验研究了不同光质(白光W、红光R、红蓝混合光RB、蓝光B)对桑树植株生长、形态和光合作用的影响。结果表明:与白光对照相比,红光、蓝光和红蓝混合光处理下植株的生长、干物质积累受到抑制;红光处理下植株的株高、叶面积显著高于白光、红蓝混合光、蓝光处理;而白光、红蓝混合光、蓝光处理下植株的LMA、叶绿素a/b比值、可溶性蛋白含量、蔗糖、淀粉含量和叶片总N含量显著高于红光处理;红蓝混合光处理下植株的Pn、Gs、ΦPSⅡ与白光处理相近,红光、蓝光处理下植株的Pn、ΦPSⅡ低于白光、红蓝混合光处理,同时红光、红蓝混合光、蓝光处理下植株的抗氧化酶活性高于白光处理,而MDA含量低于白光处理;红光处理下植株的叶片厚度、栅栏组织和海绵组织厚度显著小于白光处理。因此,一定比例的红蓝混合光可以使桑树植株的生长、光合特性、生理特征和叶片解剖结构与白光下生长植株相近,并减少单质红光、单质蓝光对植株生长发育的不利影响。     

Modified light spectral conditions prior to cryopreservation alter growth characteristics and cryopreservation success of potato (<Emphasis Type="Italic">Solanum tuberosum</Emphasis> L.) shoot tips in vitro

Light is one of the most important factors affecting growth and morphogenesis of plants. Light intensity, photoperiod and spectral composition greatly affect morphogenetic responses of in vitro plants. Modification of light spectra during recovery after cryopreservation improves survival and regeneration, but the effect of modified light conditions prior to cryopreservation are not known. Therefore, the aim of the present study was to follow the photomorphogenetic response of potato plants (Solanum tuberosum L.) under different light qualities i.e. cool white fluorescent (CW) used as control, warm white (HQI), white LEDs (W), blue LEDs (B), red LEDs (R) and a combination of red with 10?% of blue LEDs (RB) prior to cryopreservation, affecting recovery of cultivars Agrie Dzeltenie, Bintje, Maret, Anti and Désirée in vitro. Light spectral quality had a significant effect on growth characteristics of potato plants in vitro. Red light (R) promoted elongation growth but biomass accumulation remained low under monochromatic light treatments. Some of the pre-cryopreservation light treatments significantly affected post-cryopreservation success. Under blue LEDs, high early recovery was observed for all cultivars tested, whereas under red (R) or (HQI), lowest survival percentages were obtained 2–4 weeks after thawing. Specifically, during early recovery, blue light increased survival from 26 to 66?%, 4 to 31?% and 16 to 48?% for cultivars Agrie Dzeltenie, Anti, and Désirée, compared to illumination by red LEDs. Therefore, light spectral quality prior to cryopreservation can significantly affect the cryopreservation success of potato shoot tips.