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1.
Male Siamese fighting fish (Betta splendens) were conditioned to emit an instrumental response to obtain the visual image of another male of the species. The relative positive reinforcing effects of three visual stimuli capable of eliciting aggressive display were compared.  相似文献   

2.
The trillionfold concentration of sound energy by a trapped gas bubble, so as to emit picosecond flashes of ultraviolet light, is found to be extremely sensitive to doping with a noble gas. Increasing the noble gas content of a nitrogen bubble to about 1% dramatically stabilizes the bubble motion and increases the light emission by over an order of magnitude to a value that exceeds the sonoluminescence of either gas alone. The spectrum also strongly depends on the nature of the gas inside the bubble: Xenon yields a spectral peak at about 300 nanometers, whereas the helium spectrum is so strongly ultraviolet that its peak is obscured by the cutoff of water.  相似文献   

3.
Aerial visual acuity and underwater visual acuity were measured in two sea lions (Zalophus californianus) by training them to emit click bursts if they saw a striped target or to remain silent if they saw a gray target. The closest grating spacings that could be resolved both in air and under water subtended a visual angle of 5.5 minutes of arc at a distance of 5.5 meters.  相似文献   

4.
Relation of spectral types to oil droplets in cones of turtle retina   总被引:3,自引:0,他引:3  
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5.
Two-thirds of 258 fruit species from Peruvian tropical forest belong to one of two classes: large orange, yellow, brown, or green fruits with a husk; or small red, black, white, blue, purple, or mixed-color fruits without a husk. The characteristics of the two fruit classes match the size, visual ability, and jaw morphology of mammals and birds, respectively, and the animals also prefer to eat one class of fruits. Thus, most plants in this forest seem to be adapted to seed dispersal by either of two distinct broad arrays of animal taxa.  相似文献   

6.
The scarab beetle, Anomala corpulenta Motschulsky (Coleoptera: Scarabaeoidea), is a widespread and destructive pest in China. Vision is one of the most important means of acquiring information about the external environment. In order to contribute to the understanding of the perception of visual stimuli in this species, the light sensitivity and spectral responses of the scarab beetle, A. corpulenta, were measured by using an electroretinogram (ERG) technique. In total, 14 monochromatic light intensities, between 340 and 605 nm, were applied to the compound eyes of A. corpulenta under varying levels of adaptation to dark and light conditions. The results showed that all light stimuli induced an ERG response, with varied amplitudes. The spectral sensitivity curve of dark-adapted eyes showed one major peak (~400 nm; near-ultraviolet), a secondary peak (from 498 to 562 nm; yellow-green) and the third peakat 460 nm. By contrast, in light-adapted eyes, only a near-UV peak was observed. From these results, we conclude that the compound eye of A. corpulenta is likely to have at least three spectral types of photoreceptor. Significance of differences were also recorded in the responses of male and female compound eyes, as well as diurnally and nocturnally. The amplitude of ERG in response to white-light stimuli varied with the light intensity: The stronger the luminance, the higher the ERG value. This suggests that the compound eye of A. corpulenta adapts quickly to changing light conditions, enabling A. corpulenta to maintain nocturnal activities.  相似文献   

7.
采用直观分级及生物统计方法,分析了甘蓝型黄籽油菜粒色性状表现的不稳定性变化。基本规律是,粒色变化随贮藏物质的流向,由源头一端的深色向末稍一端的浅色变化。即由植株的主轴和上部分枝向基部分枝,由主轴及分枝的下部角果向主轴及分枝的上部角果,由角果的柄端籽粒向喙端籽粒方向,粒色由深变浅,千粒重也由大变小  相似文献   

8.
Under natural conditions, plants constantly encounter various biotic and abiotic factors, which can potentially restrict plant growth and development and even limit crop productivity. Among various abiotic factors affecting plant photosynthesis, light serves as an important factor that drives carbon metabolism in plants and supports life on earth. The two components of light(light quality and light intensity) greatly affect plant photosynthesis and other plant's morphological, physiological and biochemical parameters. The response of plants to different spectral radiations and intensities differs in various species and also depends on growing conditions. To date, much research has been conducted regarding how different spectral radiations of varying intensity can affect plant growth and development. This review is an effort to briefly summarize the available information on the effects of light components on various plant parameters such as stem and leaf morphology and anatomy, stomatal development, photosynthetic apparatus, pigment composition, reactive oxygen species(ROS) production, antioxidants, and hormone production.  相似文献   

9.
在不同温度条件下,烟蚜茧蜂成蜂胸部颜色可以由全部黄色变为全部黑色或黑褐色,而僵蚜壳颜色可由乳白或淡黄色变为黑褐色。此外,作者还对烟蚜茧蜂成蜂纯系后代一些常用的分类特征的变异进行了研究,结果表明其变异范围远较以往所描述者为大。  相似文献   

10.
【目的】对水稻lrd表达的光温诱导反应进行研究,明确水稻lrd表达光诱导波段和温度的抑制或促进作用。【方法】利用自有的6个水稻lrd突变体,用LED单色光源诱激和人工气候箱中不同温度梯度处理,观察类病斑的发生情况和统计病斑个数,比较诱导的效果。【结果】lrd31类病斑表达受紫外光诱导,lrd36的表达受黄光诱导,lrd37和lrd35的表达受蓝光诱导,而lrd32和lrd40在所有处理的光源下均表达类病斑;lrd32、lrd36和lrd37等3种温度下都正常产生病斑,低温明显促进病斑的发生。lrd35和lrd40在高温下不表达,在中温下可正常表达,低温下也表现促进作用,但lrd31只有在中温下正常表达,低温和高温抑制病斑出现。【结论】不同的lrd基因型所需的光诱导反应波段是不相同的。温度是抑制或促进lrd表达的另一个重要环境因子,一般是较低的温度促进lrd表达,高温抑制lrd表达。  相似文献   

11.
2个水稻黄叶突变体的遗传初步分析   总被引:5,自引:0,他引:5  
从粳稻品种中花11的转基因植株后代中,获得了2份黄叶突变体(Y-347和Y-427),经PCR等分析,表明这2个黄叶突变均与Ds转座子插入无关。通过突变体与正常中花11杂交和回交试验,证明这2个黄叶突变体均为单基因隐性突变。根据2个突变体间的杂交结果,初步表明,这2个突变体是由2个位点发生突变产生的。  相似文献   

12.
Weed Detection Using Canopy Reflection   总被引:1,自引:0,他引:1  
For site-specific application of herbicides, automatic detection and evaluation of weeds is desirable. Since reflectance of crop, weeds and soil differs in the visual and near infrared wavelengths, there is potential for using reflection measurements at different wavelengths to distinguish between them. Reflectance spectra of crop and weed canopies were used to evaluate the possibilities of weed detection with reflection measurements in laboratory circumstances. Sugarbeet and maize and 7 weed species were included in the measurements. Classification into crop and weeds was possible in laboratory tests, using a limited number of wavelength band ratios. Crop and weed spectra could be separated with more than 97% correct classification. Field measurements of crop and weed reflection were conducted for testing spectral weed detection. Canopy reflection was measured with a line spectrograph in the wavelength range from 480 to 820 nm (visual to near infrared) with ambient light. The discriminant model uses a limited number of narrow wavelength bands. Over 90% of crop and weed spectra can be identified correctly, when the discriminant model is specific to the prevailing light conditions.  相似文献   

13.
为探究斑马鱼(Danio rerio)在不同光照条件下的趋光行为差异,记录了6月龄的斑马鱼成鱼在紫外光(ultraviolet, UV)和可见光照射下的行为反应和在无光、紫光(420nm)、蓝光(460nm)、绿光(500nm)、黄光(585nm)和红光(620nm)6种光照条件下的趋光分布情况。结果表明,刺激光为UV时,斑马鱼优先游向黑暗环境一侧,刺激光为可见光时,斑马鱼优先游向可见光一侧;UV和可见光分别设置在试验区A和试验区B时,随着UV刺激强度增加,斑马鱼的偏好指数未呈现明显的增加趋势,UV和可见光同时设置在试验区B时,随着UV刺激强度增加,斑马鱼的偏好指数呈现出明显的下降趋势;5min和30min时斑马鱼的平均分布率均呈现红光区>紫光区>蓝光区>黄光区,绿光区的平均分布率在5min时高于红光区,在30min时介于紫光区和蓝光区之间。研究表明,斑马鱼趋向可见光而远离紫外光,表现出明显的避UV性和趋可见光性,且避UV性与趋可见光性之间存在显著的抑制作用,而无协同作用。此外,斑马鱼对红光、绿光和紫光的喜好程度较高,对黄光的喜好程度较低。研究结果可为斑马鱼视觉生态的...  相似文献   

14.
为分析LED集鱼灯是否适用于南海近海灯光罩网渔业,本研究进行了3种LED集鱼灯与1种传统金卤灯的生产对比试验。研究发现:(1)试验使用的LED白光灯的相对光谱功率分布有2个波峰,分别在蓝光波段,绿光、黄光波段,LED绿光灯有1个波峰为绿光波段,LED蓝光灯有1个波峰为蓝光波段,金卤灯有多个波峰,峰值波长主要在红光波段;(2) 3种LED集鱼灯的渔获率均高于金卤灯,其中LED白光灯渔获率优势明显;(3) 4种集鱼灯渔获的共同优势种为中国枪乌贼(Loligo chinensis),其中LED白光灯的渔获率明显高于其他灯具;(4)单因素方差分析结果表明LED白光灯与金卤灯捕获的中国枪乌贼的胴长、体质量均无显著性差异。研究认为LED灯尤其是LED白光灯适用于南海近海灯光罩网渔业。  相似文献   

15.
天蚕不同蛾色产卵与幼虫体色的调查   总被引:3,自引:0,他引:3  
对不同蛾色分离、产卵数量、幼虫体色、茧色和茧质调查结果表明:蛾色不同其造卵数和产卵数有差异,产卵数量最高的是黄色蛾早×黄色蛾6组合,平均为260粒,产卵净度达86.5%。浅灰色、黑色和暗黑色产卵量较低;幼虫体色可分为浅黄色和绿色2个类型,幼虫体色不同,其茧色也有差异,可分为黄色、浅黄色、浅绿色和绿色;不同茧色的茧层率差异不显著,雄茧高于雌茧的茧层率1%左右。  相似文献   

16.
研究了在室内自然光辐射下杨木和桦木染色单板的变褪色过程和影响因素.结果表明:光辐射过程中,染色单板发生了显著变褪色.经光辐射100d,各个试件色差值ΔE*均超过16,最大达44.36.染色单板光变色前期主要是由于染料及木材抽提物不饱和基团的劣化,后期主要是木材基质.染料结构及稳定性是影响其变褪色的主要因素,漂白预处理加...  相似文献   

17.
为探索不同光源对结球甘蓝(Brassica oleracea var.Capitatal)不定芽再生的影响,采用LED红光、LED黄光、LED蓝光及对照荧光灯光源,选用12-1、12-2、12-3三个结球甘蓝材料进行了研究。结果表明:在LED红、黄、蓝色光源下,外植体愈伤组织的诱导率达100%;在不定芽的诱导中,LED红光的诱导率显著大于LED黄光,与荧光灯没有显著差异,平均诱导率高低依次为:红光>荧光>蓝光>黄光;在继代过程中,从再生系数看,LED红光与LED黄光存在显著差异,与荧光灯存在较明显差异,再生系数高低依次为:红光>蓝光>荧光灯>黄光;在根的诱导中,平均诱导率高低依次为:荧光>红光>蓝光>黄光,培养期间观测发现,LED光源下诱导的根粗壮,须根多,LED红光最明显;但在LED光源培养下有明显的褪绿和瓶壁凝露现象,LED红光下凝露最重;LED光源下先长愈伤组织再长腋芽,叶片变小且易碎,生长势弱,蓝光光源下节间伸长有明显的徒长现象;而荧光灯光源愈伤组织少,腋芽生长正常,没有出现以上现象。  相似文献   

18.
光质对彩色甜椒幼苗生长及叶绿素荧光特性的影响   总被引:26,自引:0,他引:26       下载免费PDF全文
研究了不同光质 (白光、红光、黄光、绿光和蓝光 )对不同品种彩色甜椒幼苗生长及叶片叶绿素荧光动力学特性的影响。结果表明 ,白光和黄光培养壮苗的效果较好 ,其他光质依次为蓝光、红光和绿光。同一光质对不同品种彩色甜椒 Chla含量和 Chla/Chlb影响差异显著 ;采用不同光质处理 ,蓝光最高 ,白光和黄光次之 ,绿光下最低。光质对不同品种彩色甜椒的荧光参数有较大影响 ,在不同光质处理下 ,白光的 Fv/Fm、Fv/Fo、ΦPS 、qp最高 ,NPQ最小 ,表明白光为最有效光 ,其次分别为黄光、蓝光、红光及绿光  相似文献   

19.
亚洲玉米螟-近缘种云南新记录   总被引:4,自引:0,他引:4  
 在调查云南玉米螟种类的过程中,发现采自丽江县为害普通大麻 Cannabis sativa L.的玉米螟3种.其中,除亚洲玉米螟 O.furnacalis 和丽江麻螟 O.zealis lijiangensis 已报导外,于1990年11月所采的玉米螟为麻螟 O.narynensis,本种系云南省分布新记录种.  相似文献   

20.
描述了海南澳毒蛾属Orvasca Walker一新种,即异色澳毒蛾O.heterocolor sp.nov..新种与近似种的主要区别在于后翅基半部浅灰色,端半部淡黄色;抱器瓣深分叉,背侧一壁宽大,长方形,腹侧一壁相当小,三角形;阳茎直,近端部凹陷;阳茎端膜膨大,密被微刺.提供了成虫和雄性生殖器图片.  相似文献   

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