CABI

About: CABI is a nonprofit organization based out in Wallingford, United Kingdom. It is known for research contribution in the topics: Population & Introduced species. The organization has 789 authors who have published 1759 publications receiving 73843 citations. The organization is also known as: Centre for Biosciences and Agriculture International.

Cryopreservation and freeze-drying of fungi employing centrifugal and shelf freeze-drying.

Abstract: The aim of preserving a fungus is to maintain it in a viable state without change to its genetic, physiological, or anatomical characters. There are numerous methodologies available to preserve a fungus, but the two methods widely used by culture collections (biological or genetic resource centers) to achieve successful preservation are cryopreservation with liquid nitrogen using controlled-rate freezing and centrifugal freeze-drying. Generic methods are often used, but specific variations of a method may be required in order to achieve optimal stability. No single method can be applied to all fungi. More recently, techniques such as vitrification and encapsulation cryopreservation have been used to preserve recalcitrant fungi. The protocols described within this chapter have been developed over many years at one of the world's largest culture collections of filamentous fungi.

Establishment of Peristenus digoneutis and P. relictus (Hymenoptera: Braconidae) in California for the control of Lygus spp. (Heteroptera: Miridae)

Abstract: Lygus hesperus Knight is native to the western United States and is a perennial pest of numerous crops in California. It is responsible for triggering the early season application of insecticides on cotton, Gossypium hirsutum L., and strawberries, Fragaria L. Despite several surveys conducted in alfalfa (Medicago sativa L.) grown in central California, nymphal parasitoids associated with L. hesperus and L. elisus have not been found. Two exotic parasitoids were released into California beginning in 1998. Peristenus relictus (Ruhte), formerly P. stygicus Loan, and P. digoneutis Loan were collected from several locations in southern Europe and released at up to six locations over a 6-year period. At the original release site in Sacramento, a 0.25-ha plot of alfalfa, parasitism by P. digoneutis and P. relictus combined increased from zero to 90%, 3 years after the last releases were made. Parasitoids have been recovered from vacant fields of weedy annuals within 2 km of this site. Recoveries at more...

Farmers' knowledge, perceptions and management of the gall-forming wasp, Leptocybe invasa (Hymenoptera: Eulophidae), on Eucalyptus species in Uganda

Abstract: Farmers growing Eucalyptus species in Uganda were interviewed using a pre-tested questionnaire to investigate their knowledge, perceptions and management of the Eucalyptus gall-forming wasp, Leptocybe invasa Fisher & LaSalle, with the aim of developing integrated management programme for the pest. Farmers were aware of, and concerned about, the gall problem on Eucalyptus, but the vast majority of them did not know the cause. Most farmers did not attempt to control the infestation because they did not know of suitable control methods and/or the cause of the problem. Farmers' control decisions were not influenced by their experience in cultivating Eucalyptus or their education level. Only 20% of 59 farmers interviewed had received advice on L. invasa, suggesting poor flow of information on tree pests to farmers. Nearly all farmers interviewed still wanted to plant Eucalyptus, and they saw the trees as a source of several products and services. Problems relating to the increasing emergence of alien ...

DNA barcoding, phylogeny and phylogeography of the cyst nematode species from the genus Globodera (Tylenchida: Heteroderidae)

Abstract: Globodera presently contains 13 valid and three as yet undescribed species. Three species, G. rostochiensis, G. pallida and G. ellingtonae, the potato cyst nematodes (PCN), cause significant economic losses on potatoes around the world. In our study we provide comprehensive phylogenetic analyses of 455 ITS rRNA, 219 COI and 164 cytb gene sequences of 11 valid and two undescribed species of Globodera using Bayesian inference, maximum likelihood and statistical parsimony. New 205 COI, 116 cytb and 21 ITS rRNA gene sequences were obtained from 148 populations of these species collected from 23 countries. The phylogenetic analysis revealed that Globodera displayed two main clades in the trees: i) Globodera from South and North America parasitising plants from Solanaceae; and ii) Globodera from Africa, Europe, Asia and New Zealand parasitising plants from Asteraceae and other families. Based on the results of phylogeographical analysis and age estimation of clades with a molecular clock approach, it is hypothesised that Globodera species originated and diversified from several centres of speciation located in mountain regions and then dispersed across the world from these regions during the Pleistocene. High genetic diversity of Bolivian populations of G. rostochiensis was observed for both mtDNA genes. Analysis of phylogenetic relationships of G. pallida and G. rostochiensis populations revealed incongruence in topology between networks inferred from mtDNA genes, which might be an indication of possible recombination and selective introgression events through gene flow between previously isolated populations. This puts some limitations on the use of the mtDNA marker as universal DNA barcoding identifier for PCN. Globodera bravoae syn. n. is proposed as a junior synonym of G. mexicana.

Do alien plants escape from natural enemies of congeneric residents? Yes but not from all

Abstract: As predicted by the enemy release hypothesis, plants are supposedly less attacked by herbivores in their introduced range than in their native range. However, the nature of the natural enemies, in particular their degree of specificity may also affect the level of enemy escape. It is therefore expected that ectophagous invertebrate species, being generally considered as more generalists than endophagous species, are more prompt to colonise alien plants. In Swiss, Siberian and Russian Far East arboreta, we tested whether alien woody plants are less attacked by native herbivorous insects than native congeneric woody plant species. We also tested the hypothesis that leaf miners and gall makers show stronger preference for native woody plants than external leaf chewers. In all investigated regions, leaf miners and gall makers were more abundant and showed higher species richness on native woody plants than on congeneric alien plants. In contrast, external leaf chewers did not cause more damage to native plants than to alien plants, possibly because leaf chewers are, in general, less species specific than leaf miners and gall makers. These results, obtained over a very large number of plant-enemy systems, generally support the hypothesis that alien plants partly escape from phytophagous invertebrates but also show that different feeding guilds may react differently to the introduction of alien plants.