HighScore with the Plus option (HighScore Plus) is the commercial powder diffraction analysis software from PANalytical. It has been in constant development over the last 13 years and has evolved into a very complete and mature product. In this paper, we present a brief overview of the suite focusing on the latest additions and its user-friendliness. The introduction briefly touches some basic ideas behind HighScore and the Plus option.
Maize plants (Zea mays) attacked by caterpillars release a mixture of odorous compounds that attract parasitic wasps, natural enemies of the herbivores. We assessed the genetic variability of these induced volatile emissions among 31 maize inbred lines representing a broad range of genetic diversity used by breeders in Europe and North America. Odors were collected from young plants that had been induced by injecting them with caterpillar regurgitant. Significant variation among lines was found for all 23 volatile compounds included in the analysis: the lines differed enormously in the total amount of volatiles emitted and showed highly variable odor profiles distinctive of each genotype. Principal component analysis performed on the relative quantities of particular compounds within the blend revealed clusters of highly correlated volatiles, which may share common metabolic pathways. European and American lines belonging to established heterotic groups were loosely separated from each other, with the most clear-cut difference in the typical release of (E)-b-caryophyllene by European lines. There was no correlation between the distances among the lines based on their odor profiles and their respective genetic distances previously assessed by neutral RFLP markers. This most comprehensive study to date on intraspecific variation in induced odor emission by maize plants provides a further example of the remarkably high genetic diversity conserved within this important crop plant. A better understanding of the genetic control of induced odor emissions may help in the development of maize varieties particularly attractive to parasitoids and other biological control agents and perhaps more repellent for herbivores.The release of odorous compounds by plants in response to herbivore attack and the subsequent use of these odorous signals by natural enemies to locate the herbivores is a widespread phenomenon observed in various tritrophic systems, e.g. predatory mites and spider mites on Lima bean (Dicke and Sabelis, 1988), parasitic wasps and lepidopteran caterpillars on cabbage (Mattiacci et al., 1994) and cotton (Loughrin et al., 1995), and anthocorid predators and psyllids on pear trees (Scutareanu et al., 1997). We are currently studying this kind of interaction in a system that comprises maize (Zea mays), folivorous caterpillars in the genus Spodoptera, and the associated endoparasitic wasps (Turlings et al., 1990). Odor release by maize plants is a rapid systemic response (Turlings and Tumlinson, 1992) induced by elicitors present in the oral secretions of the herbivores, such as volicitin, a compound isolated from regurgitant of Spodoptera exigua Hü bner caterpillars (Alborn et al., 1997;Turlings et al., 2000).Plants belonging to various species and families differ in their odor profiles (Turlings et al., 1993b). Nonetheless, the odor patterns of different plant taxa exhibit considerable overlap, and certain compounds like the terpenoids linalool, (3E)-4,8-dimethyl-1,3,7-nonatriene, and (E)-b-ocimene seem to be qu...
Summary. Maize plants respond to caterpillar feeding with the release of relatively large amounts of specific volatiles, which are known to serve as cues for parasitoids to locate their host. Little is known about the genetic variability in such herbivore-induced plant signals and about how the emissions in cultivated plants compare to those of their wild relatives. For this reason we compared the total quantity and the qualitative composition of the odour blend among eleven maize cultivars and five wild Zea (Poaceae) species (teosinte), as well as among the offspring of eight Zea mays mexicana plants from a single population. Young plants were induced to release volatiles by mechanically damaging the leaves and applying oral secretions of Spodoptera littoralis (Lepidoptera: Noctuidae) caterpillars to the wounded sites. Volatiles were collected 7 h after treatment and subsequently analysed by gas chromatography. The total amounts of volatiles released were significantly different among maize cultivars as well as among the teosintes. Moreover, striking differences were found in the composition of the induced odour blends. Caryophyllene, for instance, was released by some, but not all varieties and teosintes, and the ratios among monoterpenes and sesquiterpenes varied considerably. The offspring of different mother plants of the Z. m. mexicana population showed some variation in the total amounts that they released, but the composition of the odour blend was very consistent within the population of this teosinte species. We discuss the ecological significance of these findings in terms of specificity and reliability of induced plant signals for parasitoids.
Summary1. This account presents information on all aspects of the biology of Fagus sylvatica L. that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation. 2. Fagus sylvatica (Beech) is a large usually single-stemmed deciduous tree native to south-east England but now growing over almost the whole of the British Isles, often planted as a forestry tree on all but the wettest soils. It forms extensive woodlands, where it is dominant over a large altitudinal range, competing primarily with Quercus robur. The outcome of this competition is determined by local soil and climatic conditions leading to a gradation into oak woodlands. It is monoecious, wind-pollinated and notable for its periodic large seed numbers (mast years); seed is dispersed by birds and mammals but mostly drops below the parent tree. 3. Fagus sylvatica is hardy, very shade tolerant, casts a deep shade and is fairly resistant to browsing but susceptible to spring frosts. 4. Due to its shallow rooting and intensive rather than extensive mode of soil water exploitation, it is also susceptible to drought, and this is likely to be the main factor controlling its expected response to climate change. 5. Fagus sylvatica is facing few conservation problems, and indeed, its range is currently expanding into central Europe. However, in the face of climate change, its range is likely to contract from its extremes in all but the north, and Phytophthora diseases may become more serious.
All representatives of an inorganic crystal structure type can be found systematically in the new database SICS (Standardized Inorganic Crystal Structures). It is derived from the Inorganic Crystal Structure Database (ICSD) by selecting the best determination of each phase. In addition, each entry is given in a standardized description and complemented by searchable descriptors Delta, which give the difference between all structures of an isopointal set. Because of the large number of structures the full information on relationships present can only be found by means of the new database itself. Some examples are given here in printed form. The limitations and the possibilities of expansion of SICS in terms of the concept of 'structure types' are demonstrated.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.