基于计算机视觉技术评价光照度对斜纹夜蛾幼虫体色的影响

【目的】为揭示光照度对斜纹夜蛾Prodenia litura(Fabricius)幼虫体色变化的影响,建立一套新的昆虫体色评价体系。【方法】采用计算机视觉检测技术,将斜纹夜蛾幼虫的颜色数值化,评价了斜纹夜蛾幼虫体色随日龄的变化规律及光照度对斜纹夜蛾幼虫体色变化的影响。【结果】随着日龄的增加,斜纹夜蛾幼虫的明度(B)和彩色指数(CI)逐渐减少,体色偏差系数(BDV)逐渐增加,色泽从开始的绿色占主导逐渐转变为红色占主导,不同日龄间主观色各颜色指标都差异显著(P<0.01);在低光照度(0~1 000 lx)下,明度(B)和体色偏差系数(BDV)主要受光照影响,而彩色指数(CI)和归一化RGB值主要受发育日龄的影响,在高光照度下(1 000 lx以上),所有颜色指标均受发育日龄影响较大,受光照处理相对较小,光照度对斜纹夜蛾幼虫体色影响的阈值为1 000 lx,在阈值下,明度(B)、彩色指数(CI)及体色分化系数(BDC)都随光照度的增加显著增加,体色偏差系数(BDV)、RGB色差则随光照度的增加而减少。【结论】光照度主要影响斜纹夜蛾幼虫体色的明暗程度,对色彩程度影响不大,且光照度的影响阈值大约为1 000 lx。     

基于计算机视觉技术的连翘果实性状变化研究

目的：探究连翘果实发育与性状之间的关系,建立基于计算机视觉技术的连翘“辨状论质”方法。方法：采用Python库LabelMe对连翘显微横切图片进行标注,获取连翘果实显微横切各部位的面积占比。采用自制软件Lq＿measure对连翘进行长度、宽度和单果面积的测量,同时称取连翘果皮（含隔膜）和种子的质量,并制作数据集。结果：连翘果实性状差异大,证实了计算机视觉技术筛选优质连翘具有工业化应用的前景,建立了一套以Lq＿measure软件为基础的连翘性状研究实验操作流程,为连翘性状数据库的建立提供了基本方法,为基于连翘果型的中药“辨状论质”理论研究提供可靠技术支撑。结论：连翘种心性状可用于鉴别连翘的果实成熟度,连翘长宽比系数和连翘果皮重占比相关性为0.74,为以后的连翘质量控制提供了理论依据。     

利用计算机视觉技术量化解析食物颜色与斜纹夜蛾幼虫体色变化的关系

【目的】为了明确食物颜色对不同日龄昆虫体色的影响,并推广利用计算机视觉研究昆虫体色的技术。【方法】本研究以斜纹夜蛾Prodenia litura幼虫为实验材料,采用计算机定量分析的方法,对取食不同颜色型人工饲料的斜纹夜蛾幼虫头部、胸部斑纹、胸腹部和背中线的红色(R)、绿色(G)、蓝色(B)和明度(L)值进行了定量化分析。【结果】结果表明:幼虫的斑纹、胸腹部背面及侧面主色和背中线的R,G,B和L值随日龄增加而下降;头部R,G,B和L值在1-3日龄增加,后随日龄的增加而下降。幼虫体色变化也受食物颜色的影响,以对1-7日龄的影响为最大;红色型食物r∶g∶b=(128~251)∶(3~129)∶(6~96)对幼虫各部位体色的影响大于黄色、绿色和紫色的食物;幼虫取食不同颜色型食物后,各部位的变异系数大小依次为:斑纹胸腹部头部背中线。最后,建立了幼虫体色与食物色彩r,g,b值及日龄的回归方程。【结论】斜纹夜蛾幼虫体色受到食物颜色的影响,且在低龄时更为显著。     

通过光谱与视觉模型研究动物体色

体色是动物进行种内和种间信息交流的重要性状特征。与人类的三基色视觉系统不同,许多动物都具有四面体颜色系统,包括人眼无法探测的紫外光区域。动物体色是动物生态学中的一项重要研究内容,以人类主观角度对动物体色进行描述和分类,可能会导致研究结果的偏差,甚至得出错误结论。该文以赤红山椒鸟(Pericrocotus flammeus)为实例,通过分段光谱分析,对动物体色的色调、色度、亮度以及各波段的亮度进行量化;通过构建先进的动物视觉模型以考虑环境光线的影响和动物视网膜对不同波段光线的敏感度和捕获能力,同时将颜色斑块直观投射在四面体颜色空间和罗宾逊投影中,以量化颜色跨度和空间容量等参数,真正实现从动物的视觉角度分析动物体色。     

影响尼罗罗非鱼视觉运动反应的因素

本文研究了环境照度、屏幕转速、水温、视野结构和体长等因素对尼罗罗非鱼视觉运动反应的影响,并描述了个体、群体及单眼鱼的反应特点。结果表明：在一定范围内,鱼的视觉运动反应随环境照度和水温的升高而增强,随屏幕转速和体长的增加而减弱。鱼对黑白垂直条纹的反应最好,对倾斜条纹的反应较差,水平条纹则不能引起明显的反应。就垂直条纹而言,在一定范围内,反应随条纹宽度和数量的增加而增强。个体和群体的反应无明显差异。单眼鱼反应明显弱于正常鱼,并有显著的方向性。     

基于计算机视觉的棉铃虫成虫雌雄自动判别研究

棉铃虫Helicoverpa armigera(Hübner)是棉花作物的主要寄主害虫,其性别的自动准确判别对区域性比、种群数量等方面的预测预报具有重要意义。本文通过CCD设备获取雌雄成虫的原始彩色图像,运用数学形态学和自适应图像增强法进行滤波分析,提高害虫RGB彩色图像及分通道图像的质量。针对RGB彩色图像提取害虫的颜色矩特征,针对B通道灰度图像提取基于灰度共生和差分统计矩阵的纹理、形态不变矩等特征,对提取的36个特征数据进行归一化处理。将惩罚因子和RBF核函数参数作为SVM分类器识别率的重要判断标准,利用K折交叉验证选取最优参数组合并建立模型,当C=4,g=0.0825,识别率达到最佳98.33%。证实了将计算机视觉应用于昆虫性别自动判别的可行性。     

计算机视觉技术在植物学中的应用

介绍计算机视觉技术的定义、组成系统和发展状况,总结其在植物学中的应用,指出目前存在的问题以及需要重点解决的关键技术,为今后的深入研究提出了一些建议和方向。     

计算机视觉在植物显微结构观测中的应用

植物显微结构计算机视觉技术的研究已得到人们的重视 ,本文综述了计算机视觉在植物显微结构中几个重要方面的研究进展 ,包括计算机视觉的形成和发展 ,计算机视觉在植物显微结构中的应用和目前植物显微结构计算机视觉系统的组成和原理。     

计算机视觉在植物显微结构观测中的应用

植物显微结构计算机视觉技术的研究已得到人们的重视,本文综述了计算机视觉在植物显微结构中几个重要方面的研究进展,包括计算机视觉的形成和发展,计算机视觉在植物显微结构中的应用和目前植物显微结构计算机视觉系统的组成和原理。     

车轮虫感染奥尼罗非鱼的白细胞分类百分比变化

车轮虫(Trichodina spp.)是奥尼罗非鱼(Oreochromis aureus×Oreochromis niloticus)养殖中最常见的一种原生动物寄生虫。实验测定了感染组和未感染组中奥尼罗非鱼的各类型白细胞的百分比。感染组该鱼血液中的淋巴细胞和嗜中性粒细胞百分比极显著高于未感染组;未感染组该鱼血液中的单核细胞百分比极显著高于感染组。发现嗜中性粒细胞和淋巴细胞可能在抵御车轮虫入侵中起着重要作用;单核细胞在抵御车轮虫起着一定的作用。表明奥尼罗非鱼感染车轮虫后,细胞免疫增强。     

A new record of Myxobolus brachysporus and M. israelensis in the tilapia (Oreochromis niloticus) collected from the Nile River,Egypt

The present study was carried out as part of an ongoing general survey for myxosporean parasites infecting tilapias in the River Nile, Egypt. In the present study, 77 Nile tilapia (Oreochromis niloticus) were collected from boat landing sites at Beni-Suef governorate, Egypt and examined for the myxosporean infection. The infection was encountered as a huge number of free spores in the kidney and the spleen. The infection showed a prevalence of 51.9% (40/77) for Myxobolus brachysporus while it was 25.9% (20/77) for Myxobolus israelensis. Mature spores of M. brachysporus were ellipsoidal and measured 8.6 × 13.2 μm. The polar capsules were subcircular with 5–6 filament turns and measured 4.7 × 3.6 μm. Spores of M. israelensis were ellipsoidal in the frontal view and fusiform in the lateral view. Spore measurements were 13.4 μm long and 8.7 μm wide. The polar capsules were elongated with 6–7 filament coils and measured 8.6 × 3.1 μm. The findings presented here proved that tilapia fishes in the Nile River are still suffering from infections with Myxobolus species. Therefore, further studies should be carried out to survey the Myxobolus infection among tilapias under culture conditions to clarify the pathological impacts of this parasite in tilapias aquaculture.     

Induction of vitellogenin production in male tilapia (Oreochromis mossambicus) by commercial fish diets

Mozambique tilapia, (Oreochromis mossambicus), are a euryhaline teleost and an important biological model species. Captive male tilapia frequently have high levels of the estrogen-induced yolk precursor protein vitellogenin (Vg), a common indicator of exposure to estrogenic compounds. Sex steroids are found in commercial fish diets, but relatively few studies have examined the relationship between commercial diets and Vg production. In a fasting experiment to ascertain a dietary role in male Vg production, plasma Vg was reduced to negligible levels after 2 weeks of fasting, while no change in estrogen receptor (ER) expression was seen. When male tilapia were fed a squid-based diet that replaced the commercial trout diet, plasma Vg was reduced to undetectable levels over 40 days, concomitant with significant reductions in hepatic expression of Vgs A, B, and C, and ERβ, compared with control fish fed commercial trout diet. Female tilapia fed the squid-based for 20 days had no change in these parameters. When male tilapia were fed a defined, soy-based diet, plasma Vg reduced to 20% of levels in fish given either commercial trout diet or a defined, fishmeal-based diet. Overall, results from these studies suggest that estrogens in a commercial trout diet induce vitellogenin production by increasing expression of Vg, but not ER genes in male tilapia.     

Spectral Test Instrument for Color Vision Measurement

Common displays such as CRT or LCD screens have hmlted capabilities in displaying most color spectra correctly. The main disadvantage of these devices is that they work with three primaries and the colors displayed are the mixture of these three colours. Consequently these devices can be confusing in testing human color identification, because the spectral distribution of the colors displayed is the combined spectrum of the three primaries. We have developed a new instrument for spectrally correct color vision measurement. This instrument uses light emitting diodes (LEDs) and is capable of producing all spectra of perceivable colors, thus with appropriate test methods this instrument can be a reliable and useful tool in testing human color vision and in verifying color vision correction.     

Orexin-B-like immunoreactivity localized in both luteinizing hormone- and thyroid-stimulating hormone-containing cells in the Nile tilapia (Oreochromis niloticus) pituitary

Immunohistochemical techniques were employed to examine orexin-like immunoreactivities in the pituitary of the Nile tilapia (Oreochromis niloticus). Rabbit anti-orexin-A serum and mouse anti-orexin-B monoclonal antibodies were used as primary antibodies. Orexin-B immunoreactive cells corresponded to luteinizing hormone (LH)- or thyroid-stimulating hormone (TSH)-containing cells, and all LH- and TSH-containing cells were immunoreactive for orexin-B. However, we found no orexin-A immunoreactive cells in the pituitary. In the Nile tilapia, an orexin-B-like substance may be secreted from LH- or TSH-containing cells and may regulate pituitary function, rather than the orexin-A-like substance in the pituitaries of Japanese seaperch and medaka.     

Preference for the presence of substrate in male cichlid fish: Effects of social dominance and context

Many cichlid species dig spawning pits or nests in soft bottoms and exhibit many substrate oriented activities. Despite this fact being of general knowledge, captive cichlids in laboratory and aquaculture set-ups are often kept in the absence of a soft substrate that they can manipulate. This raises a potential welfare issue, depending on how the substrate is valued by cichlid fish. The aim of this study is to assess the importance of substrate for male Mozambique tilapia (Oreochromis mossambicus) in social and non-social contexts. Preferences were established as a measure of time spent in two choice compartments, before and after the presence of a female. Locomotory activity, social interactions and substrate-related behaviours were recorded. Results show that dominant males prefer the area with substrate regardless of social context, and that female's presence strengthens this preference. The same preference is not apparent in the subordinate males, except for foraging. To draw conclusions on the importance of substrate to subordinates, preferences should also be assessed in agonistic contexts, during which substrate may serve to displace aggression. These results, together with related previous studies, show that the lack of substrate is particularly deleterious in a reproductive context, and thus it is likely to decrease the welfare state of breeding males of Mozambique tilapia.     

长江水系鱼体氟元素背景值特征研究

本文通过测定鱼骨氟研究了氟在鱼体中的存在特征以及氟元素背景值的地域分异特征。鱼骨氟用离子选择电极法测定。样品采集涉及长江水系１８６个江段、１２个环境单元,１２种鱼１６００余尾,分析样品１１５４个,同时分析了黄河源鄂陵湖,以及青海湖等地区几种鱼骨氟作为参考。给出了３８个环境统计单元的背景值。鱼骨氟数据以服从对数正态为主。比较了同一水环境不同鱼种鱼骨氟的差异,部分鱼种鱼骨氟差异显著,而部分鱼种两两间无显著性差异。用方差分析和多重范围分析方法分析了芜湖以上长江水系鱼体氟元素背景值,结果表明,不同环境单元同一鱼种鱼骨氟差异显著。从环境和生物因素讨论了以上统计分析结果。     

Effects of acclimation salinity on the expression of selenoproteins in the tilapia,Oreochromis mossambicus

Selenoproteins are ubiquitously expressed, act on a variety of physiological redox-related processes, and are mostly regulated by selenium levels in animals. To date, the expression of most selenoproteins has not been verified in euryhaline fish models. The Mozambique tilapia, Oreochromis mossambicus, a euryhaline cichlid fish, has a high tolerance for changes in salinity and survives in fresh water (FW) and seawater (SW) environments which differ greatly in selenium availability. In the present study, we searched EST databases for cichlid selenoprotein mRNAs and screened for their differential expression in FW and SW-acclimated tilapia. The expression of mRNAs encoding iodothyronine deiodinases 1, 2 and 3 (Dio1, Dio2, Dio3), Fep15, glutathione peroxidase 2, selenoproteins J, K, L, M, P, S, and W, was measured in the brain, eye, gill, kidney, liver, pituitary, muscle, and intraperitoneal white adipose tissue. Gene expression of selenophosphate synthetase 1, Secp43, and selenocysteine lyase, factors involved in selenoprotein synthesis or in selenium metabolism, were also measured. The highest variation in selenoprotein and synthesis factor mRNA expression between FW- and SW-acclimated fish was found in gill and kidney. While the branchial expression of Dio3 was increased upon transferring tilapia from SW to FW, the inverse effect was observed when fish were transferred from FW to SW. Protein content of Dio3 was higher in fish acclimated to FW than in those acclimated to SW. Together, these results outline tissue distribution of selenoproteins in FW and SW-acclimated tilapia, and indicate that at least Dio3 expression is regulated by environmental salinity.