Use of PCR for assessment of development in the fields of strains of Pseudocercosporella herpotrichoides, the cereal eyespot fungus
0
Citation
0
Reference
10
Related Paper
Keywords:
Eyespot
Cite
Abstract The fine structure of the eyespot of the cryptomonad Chroomonas mesostigmatica is examined. A number of unusual features are demonstrated, including the internal position of the eyespot itself, the position of the thylakoids behind it and the presence of a pair of vacuoles between the eyespot and the cell membrane. This additional information on the eyespot is discussed with reference to similar structures in other flagellated algae and the possible role it may play in phototactic responses.
Eyespot
Cite
Citations (19)
Euphorbia motuogensis M. T. Li, X. Z. Lan, H. P. Deng & W. L. Zheng, sp. nov., a new species from Motuo, Tibet, China, is described and illustrated here. It is closely similar to Euphorbia sikkimensis in having terete root, alternate leaves, well-developed pseudoumbellate inflorescence, cyathium, smooth and glaborus capsule, but Euphorbia motuogensis is clealy distinguishable by its pilose stems, involucral leaves color, secondary involucral leaves absent, cyathophylls number and color, and five similar glands. Furthermore, molecular phylogenetic analyses of sequences from both nuclear ribosomal ITS confirm that this species is distinct from morphologically similar species in this subgenus.
Euphorbiaceae
Subgenus
Euphorbia
Cite
Citations (0)
Butterfly eyespot color patterns have been studied using several different approaches, including applications of physical damage to the forewing. Here, damage and distortion experiments were performed, focusing on the hindwing eyespots of the blue pansy butterfly Junonia orithya. Physical puncture damage with a needle at the center of the eyespot reduced the eyespot size. Damage at the eyespot outer rings not only deformed the entire eyespot, but also diminished the eyespot core disk size, despite the distance from the damage site to the core disk. When damage was inflicted near the eyespot, the eyespot was drawn toward the damage site. The induction of an ectopic eyespot-like structure and its fusion with the innate eyespots were observed when damage was inflicted in the background area. When a small stainless ball was placed in close proximity to the eyespot using the forewing-lift method, the eyespot deformed toward the ball. Taken together, physical damage and distortion elicited long-range inhibitory, drawing (attracting), and inducing effects, suggesting that the innate and induced morphogenic signals travel long distances and interact with each other. These results are consistent with the distortion hypothesis, positing that physical distortions of wing tissue contribute to color pattern determination in butterfly wings.
Eyespot
Cite
Citations (9)
Electron microscopy of the eyespot of the coenobic yolvocacean Eudorina illinoiensis (Kofoid) Pascher shows that besides the well-documented anterior-posterior decrease in size, congruity of structure is involved in eyespot differentiation. In the anterior cells the eyespot lies adjacent to the plasmalemma with the thylakoid underlayers parallel to it, while in the posterior cells eyespot placement and orientation may vary considerably. Deep-sited eyespots of congruent organisation probably represent the mother-cell eyespot; discongruent ones are typical of posterior cells, but the smallest ones may be random associations of osmiophilic globules. Eyespot structure is discussed in relation to photoreception and phototaxis.
Eyespot
Phototaxis
Cite
Citations (13)
Eyespot
Divergence (linguistics)
Cite
Citations (8)
The occurrence of wheat sharp eyespot is becoming more and more serious with the change of cultivation way and the variation of climate.There were lots of research about the outbreak and the losses caused by this disease,the control techniques to this disease,and so on.However,the problems on current sharp eyespot research were the lacks of information on the inheritance,mechanism and breeding of resistance to sharp eyespot in wheat.The research strategies on breeding new varieties(lines) with high resistance or immune to sharp eyespot were reinforcing researches on inheritance and mechanism of resistance to sharp eyespot,and identifying valid resistance resources to sharp eyespot,and using biotechniques such as molecular marker,and so on.
Eyespot
Inheritance
Cite
Citations (0)
SUMMARY Developing organisms are thought to be modular in organization so that traits in different modules evolve independently whereas traits within a module change in a concerted manner. The eyespot pattern in Bicyclus anynana butterflies provides an ideal system where morphological modularity can be dissected and different levels of genetic integration analyzed. Several lines of evidence show that all eyespots in an individual butterfly are genetically integrated, suggesting that the whole pattern, rather than the separate eyespots, should be considered as a single character. However, despite the strong genetic correlations between the two eyespots on the dorsal forewing of B. anynana , there is great potential for independent changes. Here we use laboratory lines selected in different directions for the size of those eyespots to study correlated responses in the whole eyespot pattern. We show clear changes in eyespot size across all wing surfaces, which depend on eyespot position along the anterior–posterior axis. There are also changes in the number of extra eyespots and in eyespot color composition but no changes in eyespot position relative to wing margin. Our analysis of eyespot pattern modularity is discussed in the light of what is known about the cellular and genetic mechanisms of eyespot formation and the great potential for evolutionary diversification in butterfly wing patterns.
Eyespot
Modularity
Cite
Citations (61)
Abstract Numerous organisms display conspicuous eyespots. These eye‐like patterns have been shown to effectively reduce predation by either deflecting strikes away from nonvital organs or by intimidating potential predators. While investigated extensively in terrestrial systems, determining what factors shape eyespot form in colorful coral reef fishes remains less well known. Using a broadscale approach we ask: How does the size of the eyespot relate to the actual eye, and at what size during ontogeny are eyespots acquired or lost? We utilized publicly available images to generate a dataset of 167 eyespot‐bearing reef fish species. We measured multiple features relating to the size of the fish, its eye, and the size of its eyespot. In reef fishes, the area of the eyespot closely matches that of the real eye; however, the eyespots “pupil” is nearly four times larger than the real pupil. Eyespots appear at about 20 mm standard length. However, there is a marked decrease in the presence of eyespots in fishes above 48 mm standard length; a size which is tightly correlated with significant decreases in documented mortality rates. Above 75–85 mm, the cost of eyespots appears to outweigh their benefit. Our results identify a “size window” for eyespots in coral reef fishes, which suggests that eyespot use is strictly body size‐dependent within this group.
Eyespot
Cite
Citations (9)
There are fewer eyespots on the forewings versus hindwings of nymphalids but the reasons for this uneven distribution remain unclear. One possibility is that, in many butterflies, the hindwing covers part of the ventral forewing at rest and there are fewer forewing sectors to display eyespots (covered eyespots are not continuously visible and are less likely to be under positive selection). A second explanation is that having fewer forewing eyespots confers a selective advantage against predators. We analysed wing overlap at rest in 275 nymphalid species with eyespots and found that many have exposed forewing sectors without eyespots: i.e. wing overlap does not constrain the forewing from having the same number or more eyespots than the hindwing. We performed two predation experiments with mantids to compare the relative fitness of and attack damage patterns on two forms of Bicyclus anynana butterflies, both with seven hindwing eyespots, but with two (in wild-type) or four (in Spotty) ventral forewing eyespots. Spotty experienced more intense predation on the forewings, were shorter-lived and laid fewer eggs. These results suggest that predation pressure limits forewing eyespot number in B. anynana . This may occur if attacks on forewing eyespots have more detrimental consequences for flight than attacks on hindwing eyespots.
Eyespot
Cite
Citations (20)