EFFECT OF FLORAL AGING ON THE GROWTH OF COMPATIBLE AND INCOMPATIBLE POLLEN TUBES IN LILIUM LONGIFLORUM

Compatible and incompatible pollen tube growth in detached styles of three Lilium longiflorum cultivare varies with the physiological age of the style. Before anthesis both compatible and incompatible pollen tubes grow, in 48 hr, only a fraction of the distance compatible tubes grow after anthesis. Incompatible pollen tubes are restricted to about half the distance of compatible tubes in the four days postanthesis, but thereafter increase up to or three-fourths or more the length of compatible tubes at the time of floral senescence. About 10 days after anthesis, growth of both types of pollen tubes decreases. The detached style method of pollen-tube cultivation is validated in the cultivar ‘Ace’ by seed set obtained following self-pollination in the 6- to 9-day interval and failure of seed set after either self- or cross-pollination after 9 days following anthesis. Also, in agreement with detached style data, self-pollination fails to produce seeds when attempted in bud stages or the five days following anthesis. Cross-pollinations are successful in this period. This material and technique appear well suited for study of the nature of the self-incompatibility reaction.     

Nostalgia

This article describes an experimental attempt to detect differences in the cognitive styles of two-to-three-year-old children. It was demonstrated that even such young children have quite distinct behavioral styles. It was found that their cognitive styles differ in terms of whether a synthetic style or an analytic style predominates. Methods for evaluating these indices are indicated.     

Split support and split conflict randomization tests in phylogenetic inference

Randomization tests allow the formulation and statistical testing of null hypotheses about the quality of entire data sets or the quality of fit between the data and particular phylogenetic hypotheses. Randomization tests of phylogenetic hypotheses based on the concepts of split support and split conflict are described here, as are tests where splits, rather than the data, are randomly permuted. These tree-independent randomization tests are explored through their application to phylogenetic data for caecilian amphibians. Of these tests, split support randomization tests appear to be the most promising tools for phylogeneticists. These tests seem quite conservative, are applicable to nonpolar data and unordered multistate characters, and do not have the problems of nonindependence that affect split conflict and hierarchy tests. Unlike split conflict tests, their power does not appear to be correlated with split size. However, all tests are sensitive to taxonomic scope. Split support tests may help discern data that are likely to be affected by the problems of long-branches effects. Comparison of test results for mutually incompatible splits may help identify the presence of strong misleading signals in phylogenetic data. Significant split support could be a prerequisite for considering phylogenetic hypotheses to be well supported by the data, and split support randomization tests might be usefully applied prior to or as part of tree construction.     

STUDIES ON THE SELF-INCOMPATIBILITY RESPONSE OF LILIUM LONGIFLORUM

Removal of substances loosely associated with the wall of Lilium longiflorum pollen did not affect in vitro germination and tube growth, tube growth within compatible styles, or production of viable seeds. Nor was growth of pollen tubes within incompatible styles enhanced by prior removal of the loosely bound materials. Hence, these materials appear not to be recognition factors in the gametophytic self-incompatibility system of Lilium and to have no role in pollen germination. Heat treatment of selected portions of lily pistils prior to pollination indicated that the incompatibility factor(s) was located in the lower half of the style, and that the stigma plays no role in incompatibility.     

Intertwined Refractions: The Mutual Constitution of Gender Style and Class Fraction in a De-Industrializing Australian Town

Based on fieldwork among urban working-class Australians, I divide the dominated class into two fractions, dominated and dominant, and use this as a basis for analysis of the multiple gender styles which have been observed in working-class Australia. I argue that masculine style and class-fraction location are mutually constitutive. I also explain why feminine style is not as diverse as masculine style, nor is the location of women within working-class fractions as definite as that of men. Finally, I suggest that not only within the working class, but also between classes, gender style and class location are mutually constitutive.     

Analysis of stylar self-incompatibility competence by use of heat induced inactivation

Summary Immersion of Lilium longiflorum pistils in 49 °C water for increasing durations of 1,2,3, or 4 minutes immediately prior to incompatible pollination resulted in a correspondingly progressive decrease in the stylar self-incompatibility competence, as determined from the lengths attained by pollen tubes during 48 hours growth in the styles at 24 °C. Neither pistils remaining on the plant nor those detached from the plant which were immersed after anthesis in 49 °C water for 5 minutes regained self-incompatibility competence during a 48 hour incubation at 24 °C prior to incompatible pollination. Heat treatment of detached pistils as early as 39 hours prior to bud anthesis also resulted in an inactivation of stylar self-incompatibility competence when incompatible pollination was made at 24 hours after anthesis. Experiments utilizing heat treatment of partial lengths of detached whole styles revealed that pollen tubes which have grown through as much at 45 millimeters of either a physiologically incompatible or compatible portion of the style are still capable of shifting to either a higher growth rate or lower growth rate upon entry into respectively either a physiologically compatible or incompatible portion of the style.     

Symbiotic incompatibility between two forage species of Hedysarum, grown in Morocco, and their homologous rhizobia

Abstract Symbiotic experiments in the glasshouse demonstrated that two species of sulla, Hedysarum coronarium and Hedysarum flexuosum , grown in Morocco were mutually incompatible in their requirements for effectively nitrogen-fixing strains of rhizobia: nitrogen-fixing Rhizobium strains isolated from H. coronarium nodulated H. flexuosum but did not fix nitrogen, conversely strains from H. flexuosum were ineffective for H. coronarium . The agronic implications are discussed.     

Observations of pollen tube growth in Nicotiana alata and their implications for the mechanism of self-incompatibility

 Style squashes and stylar grafts were used to examine the growth of Nicotiana alata pollen tubes in self-compatible and self-incompatible styles. Compatible tubes typically showed a uniform layer of callose deposition in the walls and in small plugs spaced at regular intervals within the tube. Incompatible tubes were characterised by the variability of callose deposition in the walls and by larger, closer and more irregularly spaced plugs. There was no difference in the growth rate of compatible and incompatible tubes during growth through the stigma, but within the style most compatible tubes grew 20–25 mm day^-1 (maximum 30 mm day^–1), whereas incompatible tubes grew 1.0–1.5 mm day^-1 (maximum 5 mm day^–1). Many incompatible tubes continued to grow until flowers senesced, and only a small proportion died as a consequence of tip bursting. Grafting compatibly pollinated styles onto incompatible styles showed that the incompatible reaction could occur in pollen tubes between 2 and 50 mm long, and that inhibition of pollen tube growth occurred in both the upper and lower parts of the transmitting tract. Grafting incompatibly pollinated styles onto compatible styles showed that the incompatible reaction was fully reversible in at least a proportion of the pollen tubes. The findings are not consistent with the cytotoxic model of inhibition of self-pollen tubes in solanaceous plants, which assumes that the incompatible response results from the degradation of a finite amount of rRNA present in the pollen tube. However, if pollen tubes do in fact synthesise rRNA, the findings become consistent with this model. Received: 23 May 1996 / Revision accepted: 22 August 1996     

Social conflict models: can they inform us about human psychopathology?

Social conflict models have been proposed as a powerful way to investigate basic questions of how brain and behavior are altered by social experience. Social defeat, in particular, appears to be a major stressor for most species, and in humans, this stressor is thought to play an important role in the onset of a variety of psychiatric disorders including depression and post-traumatic stress disorder. Aggressive experience, on the other hand, may promote disorders involving inappropriate aggression and violence. Current research using animal models of social conflict involves multiple levels of analysis from genetic and molecular to systems and overt behavior. This review briefly examines a variety of these animal models of social conflict in order to assess whether they are useful for advancing our understanding of how experience can shape brain and behavior and for translating this information so that we have the potential to improve the quality of life of individuals with mental illness and behavioral disorders.     

The genetics of self-incompatibility inOenothera rhombipetala

Pollen tubes were grown under controlled temperatures in stigmas and styles which had been cut from the flowers at the point of juncture of the style with the ovary. At constant temperatures the tubes compatible with the styles grew rapidly at uniform rates. They showed accelerated growth with increase in temperature within the range 10°–30°C. Growth of incompatible tubes was irregular and slow and was neither measurably accelerated nor depressed within this range of temperatures. Routine tests for compatibility were conducted at 27°C; at this temperature compatible tubes grew through the entire length of the styles (ca. 58 mm) in 9 hours. Much of the incompatible pollen failed to germinate; that which did, grew to a maximum length ofca. 2 mm inca. 4 hours. The incompatible tubes did not even enter the styles but remained confined to the stigmas. ThreeS alleles were involved and conformed in their behavior to the gametophytic system of incompatibility. Colchicine-induced tetraploid derivatives of these plants showed no increase in compatibility.     

Growth of Trifolium pratense L. Pollen tubes in compatible and incompatible styles of excised pistils

Summary The excised pistil technique was used to study effects of pollen treatments on self-incompatibility in red clover. Pollen was treated directly with infrared or ultraviolet radiation, and indirectly with chemicals that were applied to the stigmas before pollination. The chemicals (boric acid, calcium nitrate, colchicine, cyclohexamide, gibberellic acid, glycine, and indole butyric acid) were each used at five concentrations. High dosage rates of most treatments inhibited pollen growth in styles that were genetically compatible, but none of the treatments had a specific effect on the self-incompatibility mechanism.The effects of growth of compatible or incompatible pollen tubes in a style on subsequent growth of both types of pollen tubes in the same style were studied in an experiment with 6 hr between pollinations. The passage of some compatible pollen tubes through the style did not influence either self- or cross-compatibility in the style after the second pollination. The passage of some self-incompatible tubes into the styles caused a slightly higher number of incompatible tubes to penetrate the style after the second pollination. Each pollen tube appeared to traverse the style independently of other tubes.Cooperative research by Crops Research Division, Agricultural Research Service, U.S. Department of Agriculture, and the Kentucky Agricultural Experiment Station. This article (70-3-163) is published with approval of the Director of the Kentucky Agr. Exp. Sta.     

Sexual Conflict,Life Span,and Aging

The potential for sexual conflict to influence the evolution of life span and aging has been recognized for more than a decade, and recent work also suggests that variation in life span and aging can influence sexually antagonistic coevolution. However, empirical exploration of these ideas is only beginning. Here, we provide an overview of the ideas and evidence linking inter- and intralocus sexual conflicts with life span and aging. We aim to clarify the conceptual basis of this research program, examine the current state of knowledge, and suggest key questions for further investigation.Sexual conflict arises because the sexes maximize their fitness via different, and often mutually incompatible, strategies, and its signature has been detected across a wide range of morphological, physiological, behavioral, and life-history traits in many species. A number of investigators have suggested that sexual conflict could play an important role in the evolution of two particularly interesting life-history traits: life span and aging (Svensson and Sheldon 1998; Promislow 2003; Bonduriansky et al. 2008; Maklakov and Lummaa 2013). Sexual conflict can affect life span and aging rate at both proximate (within-generation) and ultimate (evolutionary) scales. Sexually antagonistic behavioral or physiological interactions that increase mortality rate in one or both sexes (interlocus sexual conflict) could drive the evolution of faster life histories. Moreover, sex-specific optimization of reproductive strategies may often result in sex differences in life span and aging rates, and sexually antagonistic selection on shared genetic architecture can displace one or both sexes from their sex-specific optima for these traits (intralocus sexual conflict). Conversely, a change in life histories because of environmental fluctuations could affect the degree of sexual conflict in a population and influence sexual coevolution. Although evidence for sexual conflict is rapidly accumulating, our understanding of its relationship to life span and aging remains rudimentary. In this review, we provide a critical review of recent literature and highlight areas that require further investigation.     

The Dimensions, Characteristics and Functions of the Crystalline Style of Molluscs

Recent findings concerning the crystalline style dimensions in different species of bivalves under normal or unfavorable life conditions, which lead to the partial or total dissolution of the crystalline style, were analyzed. The rate of the crystalline style total dissolution in media with different pH values and under different conditions was assessed. A variety of functions and the main physical and chemical characteristics of the crystalline styles, as well as the role and contents of digestive enzymes in them, are discussed.     

Variation in singing style use in the reed bunting Emberiza schoeniclus: influencing factors and possible functions

The two main functions of bird song are territory defence and mate attraction. Considerable progress has been made in understanding how species adjust the use of songs to serve these and other (presumed) functions of bird song, but the striking variety of singing behavior observable in wild birds remains enigmatic. Some species make do with simple songs and small repertoires, while others show large, complex repertoires and still others have evolved several distinct singing styles. In most species with distinct singing styles, however, the functions of singing styles are poorly understood. Two distinct singing styles (type I and II, respectively) have long been known in the reed bunting Emberiza schoeniclus, while a new third one has recently been reported to exist. We first quantitatively investigated the evidence for the existence of three singing styles. Then, we tested predictions of the mate attraction hypothesis, the mate guarding hypothesis and the territory defence hypothesis by examining the relations between singing style use with social and temporal factors. Cluster and discriminant analyses supported the existence of three (instead of two) singing styles, which could be differentiated based on four variables referring to song structure and complexity. Use of singing styles was related to male mating status (consistent with the mate attraction hypothesis), but not to female breeding stage (no support for the mate guarding hypothesis). Finally, use of singing styles differed in relation to time of day, with the dawn chorus of paired reed buntings consisting almost exclusively of songs of the recently discovered type III singing style and daytime singing primarily consisting of songs of long‐known type I (in unpaired males) or II singing styles (in paired males). Our findings suggest that one singing style (type I) primarily serves to attract a social mate, although an additional territorial function of this singing style cannot be dismissed. The function(s) of the other two singing styles, both only sung by paired males, are not related to attraction of a social mate or to the own female's fertility, but appear to be important in the context of territory defence and extra‐pair matings.     

‘Stone is stone’: engagement and detachment in the craft of conservation masonry

Since the mid‐nineteenth century, craft has been characterized by relations of engagement, resonating with broader romantic discourses that idealize craftsmen in explicit contrast to forms of alienation linked to capitalist production. In recent work on craft, the analytic lens of engagement usefully highlights the dynamic interplay of human and non‐human agencies. Our own account builds on these ideas but suggests that the conceptual privileging of engagement creates interpretative problems, precluding ethnographic attention to the role of detachment in craft. Focusing on the skilled practices of conservation stonemasons, we describe the specific constellations of ideology and practice involved in cutting and fixing stone. Through elucidating masons’ own understandings of their work, we highlight their commitment to the ‘disciplined’ embodiment of tradition as a means of separating personal subjectivity from the stones they carve. Our analysis of the skilled practices required to work stone questions the primacy of engagement, suggesting instead that detachment and engagement are mutually implicated relational forms. This finding sheds new light on craft practice and offers a position from which to reconsider broader anthropological commitments to concepts of engagement.     

Active viewing: An Ethnography of the Indian film audience

Audiences of popular Hindi cinema¹ present a strategic site for study of the active audience as they adopt a viewing style that is participatory and interactive. In cinema theaters viewers applaud and whistle loudly, sing along with the soundtrack, shout out comments and throw coins at the screen. Viewers transform the meaning of the film and shape the collective experience of viewing. Plural audiences encounter varying interpretations of the film arising from a diversity of world views and from life‐worlds different from their own. Rather than homogenising viewers, mass produced Hindi films appear to differentiate them. The intersubjectivity of the viewing experience becomes an achievement, rather than a taken‐for‐granted. The film is seen to become a resource both for the formation of community and for the generation of conflict and the theater, a public forum and arena for situated culture wars.     

梨远缘花粉原位萌发及生长特性

应用荧光标记方法对梨远缘花粉在‘丰水’和‘噢嗄二十世纪’柱头上萌发及花粉管生长特性进行观察,结果表明:(1)梨远缘花粉均能在柱头上萌发,但其萌发率不同,授粉后24 h,在‘丰水’柱头上‘红叶桃’花粉萌发率最高,达62.8%,而‘盖县大李’花粉萌发率仅为12.0%,各种远缘花粉在‘丰水’柱头萌发率均高于‘噢嗄二十世纪’柱头。(2)各种远缘花粉管在梨柱头或花柱内生长情况也有差异,‘红叶桃’等核果类花粉管在梨柱头上均表现为扭曲、盘绕等现象,不能穿过柱头;‘红星’和‘红富士’花粉管虽然有少量穿过柱头,但不能进一步在花柱内生长,表现为扭曲变形、先端膨大等不亲和性现象。因此,梨与远缘果树杂交不亲和在柱头上就已发生,这与梨自交不亲和反应发生在花柱内的现象不同。     

Instrumentational Complexity of Music Genres and Why Simplicity Sells

Listening habits are strongly influenced by two opposing aspects, the desire for variety and the demand for uniformity in music. In this work we quantify these two notions in terms of instrumentation and production technologies that are typically involved in crafting popular music. We assign an ‘instrumentational complexity value’ to each music style. Styles of low instrumentational complexity tend to have generic instrumentations that can also be found in many other styles. Styles of high complexity, on the other hand, are characterized by a large variety of instruments that can only be found in a small number of other styles. To model these results we propose a simple stochastic model that explicitly takes the capabilities of artists into account. We find empirical evidence that individual styles show dramatic changes in their instrumentational complexity over the last fifty years. ‘New wave’ or ‘disco’ quickly climbed towards higher complexity in the 70s and fell back to low complexity levels shortly afterwards, whereas styles like ‘folk rock’ remained at constant high instrumentational complexity levels. We show that changes in the instrumentational complexity of a style are related to its number of sales and to the number of artists contributing to that style. As a style attracts a growing number of artists, its instrumentational variety usually increases. At the same time the instrumentational uniformity of a style decreases, i.e. a unique stylistic and increasingly complex expression pattern emerges. In contrast, album sales of a given style typically increase with decreasing instrumentational complexity. This can be interpreted as music becoming increasingly formulaic in terms of instrumentation once commercial or mainstream success sets in.     

Social structure, robustness, and policing cost in a cognitively sophisticated species

Conflict management is one of the primary requirements for social complexity. Of the many forms of conflict management, one of the rarest and most interesting is third-party policing, or intervening impartially to control conflict. Third-party policing should be hard to evolve because policers personally pay a cost for intervening, while the benefits are diffused over the whole group. In this study we investigate the incidence and costs of policing in a primate society. We report quantitative evidence of non-kin policing in the nonhuman primate, the pigtailed macaque. We find that policing is effective at reducing the intensity of or terminating conflict when performed by the most powerful individuals. We define a measure, social power consensus, that predicts effective low-cost interventions by powerful individuals and ineffective, relatively costly interventions by low-power individuals. Finally, we develop a simple probabilistic model to explore whether the degree to which policing can effectively reduce the societal cost of conflict is dependent on variance in the distribution of power. Our data and simple model suggest that third-party policing effectiveness and cost are dependent on power structure and might emerge only in societies with high variance in power.