The responses of adult females of Hypothenemus hampei (Ferrari) from New Caledonia, which were either resistant or susceptible to endosulfan, were compared to a range of insecticides. High levels of cross resistance were present to organochlorines (aldrin, dieldrin and lindane). No cross resistance was evident to carbaryl or organophosphates (descending order of toxicity: fenitrothion > pirimiphos-methyl > chlorpyrifos > diazinon=malathion). Carbaryl, a carbamate, was the least toxic, and avermectin, a macrocyclic lactone, was the most toxic insecticide tested on H. hampei. No evidence of synergy from esterase (DEF) or microsomal oxidase (piperonyl butoxide) inhibitors was present.

Larvae of Arenipses sabella Hmps., a serious pest of date palm trees in Israel, developed normally on inflorescences, immature or ripe rates and on green fruits of Phoenix canariensis, and their development at 30°C. took 34–45 days. Survival of males and fertilised famales was 10.8–12.0 days at 25°C. and 7.0–8.2 days at 27°C. No difference was found between survival of males and females, but unfertilised females lived rather longer than fertilised famales. The total production of eggs per female was 285 eggs at 25°C. and 328 at 27°C. At 25°C. 825 per cent. of the eggs were laid during the sixth and seventh nights of the female’s life, at 27°C. 74 per cent. were laid during the third and fourth nights. The total number of eggs laid by unfertilised females was lower than that of fertilised ones. The number of females fertilised was dependent on the number of males present in the rearing cage.

In Israel, only two generations of A. sabella— those in the spring and in the late autumn—become sufficiently large to be of economic importance. Damage occurs during only a short period in spring, when inflorescences, toung fruits and fruit stalks are attacked. In autumn and winter most larvae enter diapause. In the laboratory, the moth passes through four generations a year and even at the relatively high temperatures maintained during the winter the larvae entered a diapause.

Cadra figulilella (Gregson) is a serious pest of ripening dates in Israel and damages fruit still on the tree and also after it has been picked, if it is not then fumigated.

The time taken for development at 30°C. was 54–65 days. At this temperature adults lived for 4–6 days and the average number of eggs laid per fertilised female was 160. Unfertilised females laid fewer eggs. Most of the eggs were laid during the second and third nights after emergence of the female. The number of fertilised females depended on the number of males present in the rearing cage.

A few larvae were observed in the plantation in dropped, decaying dates throughout the year, but attack on the bunches started only when the fruit began to ripen.

Azinophos-methyl (E.C.20%) 0.5 per cent. and diazinon (E.C.25%) 0.5 per cent. were the most effective of the compounds tested. Application when the colour of the fruit began to change and again three or four weeks later resulted in excellent control of the pset.

The effects of Bt transgenic cottons (Bt-I expressing cry1Ac and Bt-II expressing cry1Ab and cry2Ab or cry1Ab and cry1Fa) and non-Bt cottons on feeding, oviposition and longevity of adults, and development and survival of Liriomyza trifolii larvae were studied under laboratory conditions; and infestation on four Bt and two non-Bt cotton traits were investigated under field conditions. Laboratory choice and no-choice tests showed that L. trifolii adults were capable of distinguishing between Bt cottons and non-Bt cottons. In a choice test on younger plants (4–5 leaves), the adults were found more often and made more feeding punctures (FP) on non-Bt cottons than on Bt cottons. On older plants (8–9 leaves), adults made the most FP on non-Bt cotton followed by those on Bt-II cottons and the least on Bt-I cotton. The females oviposited more eggs (6.7 eggs per leaf) on non-Bt cotton than on Bt-I (1.7 eggs per leaf) and Bt-II (0.8 eggs per leaf) cottons on younger plants and oviposited similar numbers of eggs (0.7–1.3 eggs per leaf) on non-Bt and Bt cottons on older plants. In a no-choice test, the females also fed more FP on non-Bt cottons than on Bt cottons on both younger and older plants. The females oviposited more eggs (15.6 eggs per leaf) on non-Bt cotton than on Bt-I (8.2 eggs per leaf) and Bt-II (6.5 eggs per leaf) cottons on younger plants and similar numbers of eggs (2.5–3.3 eggs per leaf) on non-Bt and Bt cottons on older plants. Larval and puparial survivals were not different among Bt and non-Bt cottons. The occurrence and damage of leafminers on cottons in the field showed that L. trifolii infested more plants and leaves and had more mines on non-Bt cotton than on Bt cottons.

The lesser date moth (LDM) Batrachedra amydraula is a significant pest of date palm fruits. Previously, detection and monitoring of the pest was inaccurate due to high costs of sampling with lifting machines. We report a practical system for detection and monitoring of LDM based on pheromone traps and relevant models. Dose–response experiments with LDM pheromone traps indicated a 1 mg lure is optimal for monitoring. Delta traps with adhesive covering their entire inner surface gave the highest captures while trap colour was unimportant. Sampling pheromone traps throughout the night indicated male flight began at 1:00–2:00 and reached a peak 2 h before sunrise. Monitoring traps exposed all year long in Israel revealed three generations with different abundance. Trapping transects in a date plantation indicated interference from a monitoring trap became minimal at distances >27 m away. Inter-trap distances closer than this may lower efficiency of monitoring and mass trapping in control programs. Our estimate of the circular effective attraction radius (EARc) of a 1 mg delta trap for LDM (3.43 m) shows this bait is among the most attractive compared with baits for other insects. We developed encounter-rate equations with the pheromone trap EARc to model the interplay between population levels, trap density and captures that are useful for detection of invasive LDM and its control by mass trapping. The integrated methodologies are applicable to many pest species.

We assess the genetic history and population structure of Cicada barbara in Morocco and the Iberian Peninsula, based on analysis of the mitochondrial cytochrome b gene. The divergence between Morocco and the Iberian Peninsula populations was strongly corroborated by the molecular data, suggesting genetically isolated populations with a low level of gene flow. The Ceuta population from Spanish North Africa was more similar to the Iberian populations than the surrounding Moroccan populations, suggesting that the Strait of Gibraltar has not been acting as a strict barrier to dispersal while the Rif Mountains have. The Iberian Peninsula specimens showed a signature of demographic expansion before that which occurred in Morocco, but some of the assumptions related to the demographic parameters should be considered with caution due to the small genetic variation found. The high haplotype diversity found in Morocco implies higher demographic stability than in the Iberian Peninsula populations. These results do not, however, suggest a Moroccan origin for Iberian cicadas; but the most northwest region in Africa, such as Ceuta, might have acted as a southern refuge for Iberian cicadas during the most severe climatic conditions, from where they could expand north when climate improved. The separation of two subspecies within C. barbara (C. barbara lusitanica and C. barbara barbara) finds support with these results.

Third-instar larvae of Rhopaea morbillosa Blkb. (Melolonthinae) were maintained at fixed depths between wire-mesh screens in earthenware pots during a 12-week factorial experiment designed to study the relationship between depths of feeding and damage to roots and foliage yield of Lolium perenne and Trifolium repens under two soil-moisture treatments (10% and 20%), with and without fertilisers.

Depth of feeding had a highly significant effect on relative root damage and foliage yield, and at all depths (18, 14, 12, 1, 2, and 4 in.) significantly greater root damage occurred under conditions more favourable for pasture growth.

Ryegrass was deeper rooted and suffered more damage than clover. The degree of non-linearity of root distribution with depth affected damage to roots at all depths so that species in mixed swards should suffer damage in proportion to their deep-rootedness.

It is clear that depth of feeding can confound experimental studies of damage by scarab larvae, and in the field it will influence the damage caused to pastures.

Investigation of 16 Scottish clones of Myzus persicae (Sulzer) and four of Aulacorthum solani (Kaltenbach) indicated that anholo-and androcyclic clones were predominant. A high incidence of organophosphorus resistance was found in androcyclic clones of M. persicae, but there was no indication of such resistance in A. solani. At 5°C as compared to 20°C, reproduction was decreased and development of nymphs was slower in both species. In addition, the pre-reproductive period and nymphal development time of A. solani were longer than those of M. persicae. Clonal differences in M. persicae at 5°C could not be related to origin, annual cycle or level of organophosphorus resistance, however A. solani clones from the west of Scotland may have been less affected by this temperature than those from the east. The lower limit of reproduction and development in both species was near 2°C. Neither adult survival nor fecundity of clones at this temperature were related to annual cycle, origin or organophosphorus resistance, but anholocyclic M. persicae nymphs survived longer at 2°C than holo- or androcyclic nymphs. A. solani adults survived significantly longer than those of M. persicae. M. persicae survived sub-zero temperatures better than A. solani. In neither species could percentage survival be related to stage of development, gut contents, presence or absence of wings, annual cycle, origin or organophosphorus resistance. Acclimation did, however, increase percentage survival.

The green spruce aphid Elatobium abietinum (Walker) is an introduced pest in the United Kingdom and more recently in New Zealand. In outbreak years this aphid can cause severe defoliation and sometimes death of spruce trees (Picea spp.). As chemical control is not financially viable, other options including host-plant resistance and biological control are currently being investigated. An understanding of the genetic variation of this pest is imperative in fully utilizing these control strategies. To examine this, E. abietinum was collected from Sitka spruce Picea sitchensis from four locations in the UK that were up to 240 km apart. Of these, 40 aphids were analysed via two alternative polymerase chain reaction (PCR) analyses using primer pairs. The first analysis used 10-mer random primers, whilst the second analysis used primers designed to amplify across the intergenic spacer region of rDNA. Combining results from the two analyses allowed the 40 UK aphids to be separated into 28 different genotypes. The genetic variation was also high within each UK site, with 77 to 89% of the aphids sampled being of a different genotype. The two PCR analyses were subsequently used to examine 40 aphids across six sites in New Zealand up to 1200 km apart. No genetic variation was identified. Further analysis of several of these New Zealand aphids with 87 individual 10-mer primers and two polymerase enzymes, still did not detect any genetic variation. The high degree of genotypic diversity in the UK populations was presumably due to a longer period of establishment, multiple introductions and/or sexual reproduction. The contrasting lack of genetic variation in New Zealand populations was probably due to a very limited founder population, continued isolation and lack of sexual reproduction. Reduced genetic diversity can seriously decrease the ability of a population to adapt to control strategies. Therefore the durability of certain control methods may be more readily maintained in such an isolated population in New Zealand.

Sturmiopsis parasitica (Curr.), an important larval pupal parasite of graminaceous borers in Africa south of the Sahara, was collected from Sesamia spp. and Eldana saccharina Wlk. in Ghana. Puparia were shipped to the CIBC station at Bangalore, where a rearing technique, using field-collected borers as hosts, was devised. At 26°C the larval period was 12–14 days, prepupal period 12 h, and the pupal period 12–19 days. In its 3–4 week life span a male could successfully inseminate 4–5 females, which each produced 500–900 maggots after a gestation period of 18–19 days. In the laboratory Sturmiopsis parasitica successfully parasitised Chilo auricilius Dudgn., C. partellus (Swinh.), C. infuscatellus Sn., C. sacchariphagus indicus (Kapur) and Sesamia inferens (Wlk.); it did not parasitise Tryporyza nivella (F.) or Corcyra cephalonica (Stnt.) and was only once recovered from Galleria mellonella (L.). Its potential as a biocontrol agent against graminaceous borers in the tropics is considered high.

Baseline toxicity measurements established discriminating concentrations of pirimicarb and demeton-S-methyl guaranteed to kill susceptible examples of Aphis fabae Scop., Sitobion avenae (F.), Metopolophium dirhodum (Wlk.) and Rhopalosiphum padi (L.) in the dip-test, the FAO-recommended method for detecting resistance in aphids. There was no evidence for resistance to either insecticide in field-collected populations of aphids from various parts of the UK or amongst variants of S. avenae characterised by staining their esterases after electrophoresis. New, simple techniques for rearing large numbers of colonies of cereal aphids are described.

Laboratory-bred males of Spodoptera exempta (Wlk.) required at least 48 h after emergence before responding to females, whereas wild-caught males matured in 24 to 36 h; laboratory-bred females took 60 h, whereas wild-caught females were sexually attractive to males 48 h after emergence. Mating only occurred between 00.30 and 03.00 h. Females exhibited a courtship behaviour involving ‘calling’, and the males exhibited a series of pre-mating behavioural responses, probably characteristic of physiological levels of excitement by the female's ‘calling’. Experiments showed that a male can mate with and inseminate only one female each night. The number of females inseminated by any male was related to the male's life-span and was very variable. The fertility of eggs laid by a female was not affected by the age of the male she mated with. A single mating was sufficient for the fertilisation of a life-time's production of eggs by a female.

The extent of the dependence of the foreign grain beetle, Ahasverus advena (Waltl), upon moulds in its diet was investigated.

Using a simple technique, the insect was cultured axenically at controlled temperature and relative humidity on an autoclaved mixture of rolled oats, wheatfeed and dried yeast. After the mixture was sterilised by exposure to propylene oxide vapour, virtually no larvae completed development on it in the absence of living micro-organisms, and this effect was unchanged by the addition of a mixture of B-vitamins followed by autoclaving. However, when fungi were grown on the food previously sterilised with propylene oxide, it again permitted the complete development of the insect.

Autoelaved wheat germ was not a suitable diet for A. advena unless a small proportion of dried yeast was added before autoclaving. It is concluded that living fungi are not essential in the diet of the insect, but that they may supplement an otherwise inadequate diet.

The minimum development time from egg to adult on a complete food at 80 per cent. E.H. and 30°C. varied from 18 to 25 days.

This paper brings together all the species of Microphanurus from the Ethiopian and Indo-Malayan regions that I have written about during the last eight years. I have found that the fauna of neither region could be studied in isolation if a proper understanding of the taxonomic relationships and host-preferences of the genus were aimed at.

The key contains all the species from the regions concerned of which the types or at least authentically named specimens are in the British Museum. Two new African species are described.

For the identification of the Hemipteron, Atelocera stictica, Westwood, and for other information I am much indebted to Mr. W. E. China.

An account is given of a survey of the sandfly fauna of Iraq made in 1949 and 1950. Two new species, one of which has been previously misidentified, and two new varieties are described, and brief notes are given on all the 12 species of Phlebotomus and Sergentomyia taken in the survey. A description is given of a male of P. palestinensis taken in Baghdad, as it differs from the male described from Jericho. Keys to the Phlebotominae in Iraq and neighbouring territories are included, together with a Table showing their distribution.

Relationship between distribution of human dermal leishmaniasis and the species of Phlebotomus is shown on a map, supporting the belief that P. sergenti is the principal, if not the sole, vector of oriental sore in Iraq.

The distribution of Sergentomyia is given in another map indicating that, in contrast to Phlebotomus, the individual species of Sergentomyia are confined to one or other side of the boundary between the Saharo-Sindian and the Irano-Turanian zoogeographical regions.

A rapid visual field screening technique for resistance of cowpea (Vigna unguiculata) to the legume pod borer Maruca testulalis (Geyer) was developed. The methodology involved measurement of two damage parameters: field examination of flowers for signs of M. testulalis injury or larval presence (i.e. rapid visual technique - flowers) and/or a pod evaluation index, from the ratio of pod load to pod damage (i.e. rapid visual technique - pods). Highly significant (P <0.01) correlations were obtained between the rapid visual field screening technique and the existing field screening technique. The latter is recommended as a fast and precise method for initial screening large collections of genotypes while the former should be used for more detailed selection and other resistance studies. The technique described here uses fewer variables than the previous method and thereby reduces costs while improving efficiency and precision.

A variety of host and non-host meals were tested for their potential in triggering oogenesis and oviposition in females of Cephalonomia stephanoderis Betrem, a synovigenic parasitoid of the coffee berry borer, Hypothenemus hampei (Ferrari). The consumption of non-host meals or meals composed of honey and crushed host eggs or pupae was insufficient to initiate oogenesis. The presence of suitable hosts for oviposition appeared essential for inducing oogenesis and oviposition in this parasitoid. Whereas females may host-feed on all developmental stages of H. hampei, these were not equally suitable in stimulating oogenesis and oviposition. In no-choice tests, oogenesis and oviposition were observed only in females supplied with fully-developed larvae, prepupae and pupae. Direct contact with hosts apparently stimulated egg maturation and egg-laying. Delaying the allocation of energy to egg production until suitable hosts are available for oviposition may be an adaptive attribute of a parasitoid of a concealed and patchily distributed host such as H. hampei.

Cosmopolites sordidus (Germar) is an important pest on bananas and plantains. Population build-up is slow and damage becomes increasingly important in successive crop cycles (ratoons). Yield loss results from plant loss, mat disappearance and reduced bunch size. Damage assessment requires destructive sampling and is most often done on corms of recently harvested plants. A wide range of damage assessment methods exist and there are no agreed protocols. It is critical to know what types of damage best reflect C. sordidus pest status through their relationships with yield loss. Multiple damage assessment parameters (i.e. for the corm periphery, cortex and central cylinder) were employed in two yield loss trials and a cultivar-screening trial in Uganda. Damage to the central cylinder had a greater effect on plant size and yield loss than damage to the cortex or corm periphery. In some cases, a combined assessment of damage to the central cylinder and cortex showed a better relationship with yield loss than an assessment of the central cylinder alone. Correlation, logistic and linear regression analyses showed weak to modest correlations between damage to the corm periphery and damage to the central cylinder. Thus, damage to the corm periphery is not a strong predictor of the more important damage to the central cylinder. Therefore, C. sordidus damage assessment should target the central cylinder and cortex.

Infestations of the rice gall midge Pachydiplosis oryzae (Wood-Mason) in Ceylon were studied in 1968. The three larval instars, the prepupa and pupa are described. Total development time is 18–22 days. Dissection of infested rice seedlings showed that first-instar larvae move in 6–12 h from the leaves where they hatch to the shoot apices to which they are specifically attracted, without boring into plant tissues. Larvae feed at the base of the growth cone throughout their development; if more than one larva reaches a shoot apex only one individual survives to maturity. Gall formation results from suppression of the growth cone, development of radial ridges from the innermost leaf primordium just above the level of the posterior end of the larva, and then an elongation of the leaf sheath. Death of the larva, achieved experimentally by means of diazinon or fenitrothion applied to the soil, up to and including instar 2 was followed by renewed activity of the growth cone, but after the same treatment during instar 3 the growth cone was not re-activated. The development of the gall is seen as being due to diversion of nutrients from the growth cone to the midge larva, and possibly by substances produced by the first-instar larva and prepupa which stimulate growth of the radial ridges and gall elongation, respectively. Firstinstar larvae develop only in active shoot apices; thus development proceeds normally in the terminal apex, but is inhibited in the inactive axillary shoot apices. Under high population pressure all shoot apices become infested, but larval dormancy results in staggered gall formation and adult emergence. Larval dormancy in inactive axillary shoot apices may explain seasonal carry-over of the pest.

Field and laboratory studies have shown that the several root-infesting Anthomyiid flies differ greatly in the number of generations composing their annual cycle and in the minimum temperature conditions necessary for full activity.

Onion flies (Delia antiqua (Mg.) ) were mainly univoltine in laboratory cultures. Of 369 first-generation pupae studied in 1953, only 141 (about 40 per cent.) gave rise to flies in July-August and 228 (about 60 per cent.) entered a diapause, in which 196 (about 85 per cent, of those entering diapause) remained until the following spring. In 1954, 99 per cent, of the first-generation pupae from univoltine flies and 97 per cent, of those from bivoltine flies entered the overwintering diapause in July. It then appeared that exposure to low temperatures during the development of the first-generation larvae had induced diapause in the pupae. This was confirmed by the unexpectedly high proportion (49 per cent.) of wild first-generation pupae which entered the overwintering diapause in July in the cool summer of 1954. It was also established that the spring oviposition period for D. antiqua began about the end of May, and it appeared that, in the field, air temperatures of approximately 70°F. were necessary to stimulate egg-laying. First-generation flies emerged in the second and third weeks of July, their numbers depending on the temperature in June. A few second-generation flies, together with late first-generation flies, may emerge in September, but the temperature is then too low for oviposition and there seem to be no third-generation larvae.

This is the first of a series of papers based on results of breeding experiments and on observations in the field. It is hoped that a full inventigation of the biology of this species will be of value in elucidating the many difficult biological problems of the Aphididae.