Forest loss has caused fragmentation and destruction of habitats, and thereby presents serious extinction risk to many endemic species in Madagascar. Among many other arthropod groups, carabid beetles are poorly known in Madagascar as regards their distribution, habitat requirements and taxonomy. The aim of this study is to document community composition, distribution patterns and habitat preferences of carabids in the forest-dominated Ranomafana National Park, south-eastern Madagascar. Carabids were collected by hand and trunk traps from secondary forest, primary forest and nearby village areas. In total, 4314 individuals representing 125 species, including 38 new species, were collected. Almost 70% of the species were recorded in very low abundances. Furthermore, there were only a few species in intermediate abundance classes, while the three most abundant species represented ~36% of the total catch. The carabid community seems to be very species rich, consisting mostly of species in low abundances. A positive correlation was found between abundance and occupancy despite high variation among species distribution patterns. Small population sizes of endemic species with nearby habitat destruction make the species especially vulnerable to extinction and increase the importance of protecting Ranomafana National Park.

Root-knot nematodes (RKN) are serious pests of tomato production in Kenya. Accurate identification of the plant parasitic nematodes is important for their effective management. A study conducted to assess their prevalence and identify RKN occurring on tomatoes in Central Kenya showed infestation of the crop in all the three districts. Of the total sampled plants (N = 900), the RKN infestation level ranged from 28 to 62%. RKN disease severity ranged from 2.5 to 5.3 in all the locations. Meloidogyne incognita,M. javanica and M. arenaria were the only species found infesting tomatoes in these areas. Female nematodes sampled from the symptomatic root system that had root galls characteristic of RKN were analysed by isozyme phenotypes of esterase (EST) and malate dehydrogenase (MDH). EST phenotype was polymorphic and enabled identification of the three different species, while MDH was monomorphic. Polymerase chain reaction-restriction fragment length polymorphism with region between mitochondrial cytochrome oxidase subunit II and large subunit ribosomal RNA (mtDNA COII-LSUrRNA) using HinfI showed that all isolates of M. incognita could be digested into three restriction fragments of about 1300, 400 and 100 bp, except for one species that showed an additional restriction site, giving four fragments of 900, 420, 380 and 100 bp. The 1800 bp PCR product of M. javanica was not digested by HinfI. Meloidogyne arenaria (EST phenotype A1) PCR product was digested into two restriction fragments of about 1700 and 100 bp, while M. arenaria (EST phenotype A2) had two restriction fragments at 1100 and 100 bp.

Despite the continuous use of synthetic insecticides during the last two decades, the tea mosquito bug Helopeltis theivora Waterhouse still exists as the most destructive pest of tea in North East India. The susceptibility levels of the female sucking bug collected from conventional (synthetic insecticide treated: Terai and Dooars plain regions) and organic (synthetic insecticide untreated: low-altitude Darjeeling region) tea plantations of the northern part of West Bengal to two synthetic insecticides, quinalphos and cypermethrin, and the activity of three principal detoxifying enzymes were assayed. Compared with the susceptible Darjeeling population, the Terai and Dooars populations showed a resistance factor at the lethal concentrations for 50% level ranging from 547- to 2680.87-fold and from 3810- to 7480-fold for quinalphos and cypermethrin, respectively. General esterases (GEs), glutathione S-transferases (GSTs) and cytochrome P450-mediated mono-oxygenases (CYPs) also showed an increased activity in the Terai and Dooars populations compared with those from Darjeeling. Defence enzyme activity was enhanced by 15.4- and 17.6-fold for GEs, 1.8- and 1.9-fold for GSTs and 2.1- and 2.4-fold for CYPs in the synthetic insecticide-treated H. theivora populations when compared with the untreated Darjeeling populations. Electrophoretic analysis for GEs showed a higher level of expression for esterase I–VI isozymes in the Terai and Dooars populations when compared with that in the Darjeeling populations. This study reveals a reduced efficacy of quinalphos and cypermethrin against field populations of H. theivora, possibly due to enhanced activities of GEs, GSTs and CYPs. The findings may be used in developing integrated resistance management strategies that can help in the effective control of this major tea pest.

Powdered maize cobs were tested as an alternative for pesticide use in stored maize. Five doses (2, 4, 6, 8 and 10 g/250 g seed) of powdered maize cobs applied at particle sizes of 1.4 and 0.4 mm diameter were compared with actellic powder against Sitophilus zeamais Motschulsky for 120 days. Mortality and survival data showed that cob powders did not act as fumigant but exerted a potent inhibition of progeny on direct contact with S. zeamais adults. The particle size of powdered cobs had no effect on maize damage and losses. At doses equal to or higher than 6 g powdered maize cobs/250 g grain maize, i.e. 2.4% (w/w), damage to grain was < 5% and weight losses < 1%. The protection offered at the highest dose was comparable to the pesticide control. The use of powdered maize cobs is discussed as a natural alternative to synthetic pesticides for protection of maize against S. zeamais.

A new genus and a new species of the parasitoid wasp, Napo townsendi (Hymenoptera: Braconidae: Euphorinae: Dinocampini), is described from the Yanayacu Biological Station in Napo Province, Ecuador. The new genus and species is diagnosed and compared with the most closely related genus Betelgeuse Shaw and other Dinocampini. While first discovered by yellow bowl and Malaise trapping, it has more recently been discovered that males of N. townsendi can be found preferentially perching on the leaves of seedlings of the asteraceous tree Dendrophorbium lloense (Hieron) C. Jeffrey.

Red palm weevil Rhynchophorus ferrugineus Olivier is a key pest of date palm in the Kingdom of Saudi Arabia. Since 1994, the Ministry of Agriculture has implemented a pheromone-based integrated pest management (IPM) strategy to control R. ferrugineus in the Kingdom. Geographic information system (GIS) technology can serve as a valuable tool to assess insect activity and in addition the impact of the control strategy. We used GIS-based techniques to ascertain the spatial and temporal spread of R. ferrugineus in 234 ha of date plantation in Al-Sohemia-1 in the Al-Ahsa region of Saudi Arabia. One hundred and fifty six pheromone (Ferrolure™) traps in Al-Sohemia-1 were logged using the Trimble global positioning system to determine the east longitude and north latitude of each pheromone trap and transformed to the GIS as a shape file. The spatial and temporal variations for R. ferrugineus activity based on captures in pheromone traps were studied for each of the four seasons of the year and also year-wise during 2009 and 2010. Results revealed that during both 2009 and 2010, maximum weevil activity was recorded during late spring and early summer, with captures declining during autumn and winter. Spatial variations in the activity of R. ferrugineus indicated that in general 2009 registered lower weevil activity compared with 2010. Furthermore, most of the area exhibited medium to very high weevil activity in spring and summer during both 2009 and 2010, while most of the area recorded very low to low weevil activity during the autumn and winter seasons of both the years. The ongoing R. ferrugineus-IPM programme in Al-Ahsa needs to be strengthened in areas showing high to very high weevil activity.

Ant–acacia mutualisms are conspicuous biotic associations in Savannah and neotropical ecosystems; however, the effects of tree size and forest structure on ant behaviour and tree traits are rarely examined. We tested two hypotheses related to these effects: (1) ant responses to disturbance are influenced by tree size and forest basal area; and (2) tree traits important to ants are predictable by tree size and forest basal area. We investigated these hypotheses in a dry tropical forest (Ometepe Island, Nicaragua) with the myrmecophytic Collins acacia (Vachellia collinsii Saff.) and the ant Pseudomyrmex spinicola (Emery 1890). We measured trees from three size classes and three basal area classes and quantified resources that are important for ants, including food resources (nectaries and Beltian bodies) and domiciles (thorns), as well as a measure of potential tree reproductive fitness (seedpods). We also evaluated ant responses to experimental disturbances. Three important findings emerged: (1) on average, 1140–1173% more ants responded to experimental disturbances of large trees than small- or intermediate-sized trees, respectively; (2) forest basal area did not affect ant responses to disturbance; and (3) neither tree size nor forest basal area was correlated with branch-level mean numbers of nectaries, food bodies or thorns. Our studies support the hypothesis that tree size is an important factor regarding ant behavioural responses to disturbance, but not forest basal area. Our work suggests that future studies of ant behaviour on myrmecophytes should consider tree size.