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AbstractEight potato (Solanum tuberosum)cultivars were transformed with a modified cry1Ac9 gene under the transcriptional control of the CaMV 35S promoter using Agrobacterium‐mediatedtransformation with a nptII gene conferring kanamycin resistance as a selectable marker. Initially the transformation efficiency of two Agrobacteriumstrains (LBA4404 and AGL1) were compared using the potato cultivars ‘Iwa’ and ‘Ilam Hardy’. Both strains resulted in similar numbers of regenerated shoots, but there was a higher proportion of off‐types among plants transformed using the AGL1 strain. Subsequently, the cultivars ‘Karaka’, ‘Pacific’, ‘Red Rascal’, ‘Rua’, ‘Russet Burbank’, and ‘White Delight’ were transformed with strain LBA4404. Putatively transformed lines with kanamycin resistance were assayed using multiplex polymerase chain reaction (PCR) with an endogenous potato actin as an internal control. From a total of 116 lines, 105 were confirmed as being PCR‐positive for the nptII gene, of which 93 were also PCR‐positive for the presence of the cry1Ac9 gene. The amount of Cry protein in all transgenic lines tested was less than 60 ng/g fresh leaf tissue. The growth of potato tuber moth (Phthorimaea operculella)larvae was inhibited by foliage from greenhouse‐grown plants of 77 of the transgenic lines (P <0.05). Fifty‐five of these resistant transgenic lines were described as having a phenotypic appearance comparable to the corresponding parental cultivars, when grown in the greenhouse. Southern analysis on four highly resistant lines revealed they contained two to five copies of the cry1Ac9 gene. Several transgenic lines severely reduced larval growth while exhibiting a phenotype similar to their parent cultivar. These lines warrant further investigation in the field.

The density and species composition of ground-dwelling spiders were assessed using suction sampling from August 1994 to July 1995 at various distances from a field edge into a single grazed pasture, and from March 1996 to March 1997 in the same and three additional grazed pastures and adjacent fenced shelterbelts on the Canterbury Plains, New Zealand. Spider density declined rapidly with distance from the shelterbelt (mean 241 m-2) into the pasture (means 72.5 m-2 at 2.5 m, and 10.3 m-2 at 5 m). Mean spider densities in the four pastures were 53.0 m-2 while in the shelterbelts they reached 316 m-2. The fauna in both habitats was dominated by the European linyphiid, Tenuiphantes tenuis (Blackwall). An unidentified theridiid was common only in the shelterbelt, while unidentified immature linyphiids and theridiids were common in both habitats. Of the c. 28 species collected, 25 were found in shelterbelts, and 13 in pasture. Thirteen endemic, one native, and one introduced species were found only in shelterbelts, while from pasture all but two endemic species were also recognised from shelterbelts. There was little evidence that the shelterbelts acted as refuges for spiders which could subsequently disperse to the adjacent paddocks.

Nothofagusspecies from Chile and New Zealand were surveyed in the field for invertebrate abundance and leaf feeding damage and in the laboratory for antifeedant activity against leafrollers (Ctenopsteustis obliquana, Epiphyas postvittana), deterrent activity against pea aphid (Acyrthosiphon pisum), insect growth regulatory activity (Oncopeltus fasciatus), nematicidal activity (Caenorhabditis elegans), antibiotic activity (Pseudomonas solanaciarium), and general toxicity. A data matrix indicated that N. alessandriand N. pumiliomost likely have a chemical barrier to insect attack as leaves showed low faunal abundance, low herbivory, and activity in the leafroller antifeedant, aphid deterrent, and nematicidal assays. A chemical examination of N. alessandrithat used the leafroller antifeedant test to guide the separation yielded an active fraction containing the flavonoid, galangin, and the stilbene, pinosylvin, which appear to act in concert to deter leafroller feeding. The discovery of the phytoalexin, pinosylvin, in the leaves, raises the possibility that Nothofagusin general, and N. alessandriin particular, may have induced chemical defense mechanisms.

Experiments were conducted in lucerne to determine the efficiency of vacuum sampling of insects and whether this was affected by the height of vegetation sampled. Three insects of significance as predators of pests in Australian lucerne were studied: transverse ladybird beetle (Coccinella transversalisFabricius), pollen beetle (Dicranolaius bellulus(Guérin-Méneville)), and spined predatory shield bug (Oechalia schellembergii(Guérin-Méneville)). In a preliminary experiment comparing a commercially harvested area of lucerne with an unharvested area within the same crop, the proportions of released insects recaptured from unharvested lucerne were significantly lower than recoveries from the shorter, harvested lucerne. Resampling the tall lucerne after it was cut by hand gave cumulative recapture proportions which did not differ from those observed for the harvested lucerne. A second experiment with a randomised replicated design re-tested the hypotheses of the preliminary experiment for two insect species. Very similar results were obtained. This verification showed that recapture efficiencies from tall lucerne ranged between 0.60 and 0.74 but that resampling after hand cutting gave cumulative recapture proportions in excess of 0.86 which did not differ from recapture proportions from short lucerne.

This paper investigates the hypothesis that a rapidly induced phytochemical response to grazing damage, such as that seen in tomato, serves to deflect insect herbivores away from leaves soon after damaging them (the grazing dispersal hypothesis). As a result, grazing damage is more dispersed than it otherwise would be, and young leaves, which may be of particular importance to a plant in competition for light, are not damaged excessively. In the first experiment, artificial removal of c. 15% of leaf area led to a significant reduction in plant performance compared with undamaged controls, but only when the plants were grown together in competition for light. The second experiment demonstrated that the distribution of grazing damage within the plant was an important factor in the outcome of competition; in those plants in which grazing was applied to the lower leaves there was no effect of damage upon performance compared with undamaged controls, whereas grazing to the upper leaves significantly reduced plant performance. A third experiment provided some insight into how this interaction between damage and competition comes about. It was shown that damage to leaves led to a rapid drop in the rate of extension growth of the main shoot, especially when the upper leaves were damaged, and normal rates of growth were not resumed for at least 3 days. It is argued that in a rapidly growing canopy, such an effect may mean that a damaged plant loses its position in the height hierarchy. The final experiment showed that previous damage to plants can affect the distribution of subsequent grazing by larvae of Spodoptera littoralis, apparently through a wound-induced reduction in leaf palatability. Plants which had been artificially damaged 48 h previously were grazed significantly less than controls, and the avoidance effect was greatest in the young leaves. These results are consistent with the grazing dispersal hypothesis, and suggest that rapid wound-induced responses may be of greatest significance in species characteristic of fertile environments where competition for light is particularly intense.

Leaves of soybean (Glycine max (L.) Merr.) and cotton (Gossypium hirsutum L.) were mechanically damaged with a single hole and offered to Spodoptera littoralis Boisd (Lep., Noctuidae) larvae in laboratory bioassays at intervals of between 0 and 7 days from damage. The subsequent within-leaf grazing patterns of damaged and undamaged areas were compared using an image-analysing computer, and estimations were made by eye of percentage, areas grazed at three spatial scales. Reduction in palatability of damaged areas of both plant species was detected, at time intervals ranging from 0 to 7 days after damage. This effect was strongest for the longer time intervals and the effect became weaker with increasing distance from the site of damage. These results are discussed in relation to possible defensive roles of wound-induced changes.

Undamaged foliage of sixteen species of broadleaved trees was assessed for background (constitutive) palatability using larvae of Spodoptera littoralis (Lepidoptera) in laboratory bioassays. Palatability (dry weight consumed in 48 h) varied significantly between species and exhibited a four-fold range. Leaves of fifteen species were damaged artificially in the field and offered with control (undamaged) leaves to Spodoptera after 48 h and two weeks on the tree. Leaves adjacent to the damaged ones were similarly tested. Ten species exhibited significant (P<0.02) wound induced declines in palatability; damaged and adjacent foliage was involved. Although there was no significant relationship between the trees' constitutive palatability and the number of invertebrate herbivore species they support, this previously-demonstrated relationship closely approached significance when the species showing wound-induced effects were excluded from the regression. These results are discussed within the limitations of laboratory bioassays and the possible field consequences are briefly considered.

Abstract. 1. Small arenas in the field were used for observing adult Agonum dorsale (Pont.) foraging in a wheat crop. 2. The carabid showed no significant change in behaviour between low and high aphid density arenas. 3. Individuals foraged nocturnally and spent most of their time on the ground searching for prey. They climbed infrequently and then not high enough to reach aphid aggregations on the ears and flag leaves of wheat. 4. Gut dissection showed that more individuals had eaten aphids in the high aphid density arena than the low. Recording of aphid distribution within the arenas showed that this increase in aphid consumption could be explained by A.dorsale capturing aphids on the ground. Prey availability per unit area was in fact higher on the ground than on the wheat. 5. The contribution of ground‐zone predators such as A.dorsale to the control of cereal aphids will be determined by the frequency with which aphids arrive on the ground and the proportion of these which reclimb the wheat and reproduce in the absence of predation.

Abstract. 1. Leaves of tomato (cv. Moneymaker) were artificially damaged and offered to Spodoptera larvae at a range of intervals following damage. Grazing levels on these leaves were compared with those on undamaged leaves on the same or different plants. 2. In separate experiments, three leaves in a middle position on the main stem were clipped and after 48 h grazing levels on undamaged leaves above and below those damaged were compared with similar leaves from control plants. 3. Within 8 h, grazing levels on damaged leaves were significantly lower than those on control leaves, and within 24 h, leaves adjacent to damaged ones were similarly affected. These effects persisted for at least 7 days and leaves above and below those damaged were affected. There was up to nine‐fold reduction in area consumed. 4. The possible ecological consequences of reduced palatability at these levels are discussed.

Experiments were conducted in 1989 and 1990 to investigate the mechanism underlying patterns of invertebrate population recovery in winter wheat following treatment with the broad‐spectrum insecticide dimethoate. Predation of Drosophilapupae and artificially induced aphid populations was monitored at different distances into plots treated with dimethoate. An initial drop in predation was recorded in all positions following treatment. Predation rate then showed a period of recovery, which progressed from the edge to the centre of the treated plots. This pattern of recovery corresponded to the numerical pattern of recovery of the predatory invertebrate groups; Carabidae, Staphylinidae and Linyphiidae. The results are discussed in terms of mechanisms to explain observed patterns of recovery of invertebrate ‘prey’ groups such as aphids. It is concluded that the ranking of pesticides by their toxicity alone would fail to take into account ecological processes that determine the different patterns of population change following treatment.

Tasmanian blackwood (Acacia melanoxylon) trees of six geographic provenances were tested for susceptibility to insect attack. In one group of trees insects were excluded using insecticide, while trees in a similar group were untreated. Psyllids (Psylla acaciaeand P. uncatoides) significantly reduced growth rates of unprotected trees. Leaf miner (Acrocercops alysidota) did not cause leaf abscission but influenced tree development through shoot abscission, which lead to multi-leadering. The rate of mature foliage (phyllode) development was not influenced by insect infestation; it is more likely to be determined by genetic and environmental conditions.

AbstractPitfall trapping (November 1993 to April 1994) and Malaise trapping (January to June 1995) were carried out to study the predatory arthropod fauna in carrot fields at four sites in Canterbury, New Zealand. Staphylinidae (rove beetles), Linyphiidae (money spiders), Lycosidae (wolf spiders), Phalangiidae (harvestmen), and Carabidae (ground beetles) were the most abundant predators. At Lincoln, spiders, staphylinids, harvestmen, and carabids comprised 68, 13, 11, and 2.6 percent, respectively, of all total predaceous arthropods in pitfall traps. At Killinchy (30 km from Lincoln) these four taxa constituted 77, 8.5, 0.7, and 6.5 percent of the pitfall trap catches. Overall, a total of 33 staphylinid species was recorded, including one, Ocypus ater(Gravenhorst), which was new to New Zealand. The total number of predators caught in pitfall traps declined in March and April.In pitfall traps the abundant species were the staphylinids Amischa analis(Grav.), A. nigrofusca(Step.), Atheta fungi(Grav.), A. amicula(Step.), and Xantholinus linearis(Oliver); the carabids Meta‐glymma moniliferBates and Holcaspis angustulaChaudoir; the spiders Lepthyphantes tenuis(Blackwall), Erigonespp. and ’Lycosa’ hilarisKoch; and the harvestman Phalangium opilioL. In Malaise traps, abundant staphylinid species were Tachyporus nitidulus(Fab.), Amischa decipiens(Sharp), and Atheta fungi(Grav.). The seasonal activity and abundance of the dominant species are described, and their potential importance in control of carrot rust fly (Psila rosaeF.) and pests in other crops is discussed.

Many insects which are useful as biocontrol agents feed on pollen and nectar as adults. Nectar and pollen sources (as “companion plants") can be grown around or within crops to increase the density and diversity of predators and parasites. Plants vary in their suitability for such uses, however, and in this work, three cultivars of Coriandrum, two of Phacelia, and one each of Anethum and Fagopyrum were compared with respect to their sowing-to-flowering times, and susceptibility to low temperatures in Canterbury, New Zealand. There were large differences between cultivars with respect to sowing-to-flowering times. The time to flowering was the greatest with autumn sowings and Anethum was the most noticeably delayed. Fagopyrum failed to flower from March to July sowings, indicating a sensitivity to low temperatures or frosts; however, it had the shortest sowing-to-flowering period of all plants tested. The possibility of assessing other Fagopyrum cultivars for their tolerance to low temperatures and their ability to flower in early summer is discussed.

Flight activity of Psila rosae F. (Psilidae) was monitored with yellow sticky traps (Rebell®) in the North and South Islands of New Zealand over a 13-month period in 1993/94. Three distinct periods of adult flight activity were observed, indicating three generations per year. At Lincoln (the South Island site), the first flies were caught in early October 1993 and the first flight peaked in mid-late October, followed by a second peak in mid-late January, and a third peak in mid March-mid April. At Feilding (the North Island site), the peak catches of second and third generation flies were 10 and 22 days earlier than at Lincoln, respectively. In both islands, more female than male flies were captured in the first and second generation flight periods whereas more males than females were captured in the third generation.

The effects of manipulating sowing and harvest dates on the degree of carrot rust fly (Psila rosae) damage on carrots (Daucus carota) was investigated at Lincoln University, Canterbury, New Zealand in 1994-95. The proportion of damaged carrots resulting from late sowings (mid November-late December) and harvested before the third carrot rust fly generation was lower than those sown earlier (early-late October). However, a reduction in growing time for later sowing dates resulted in roots which were not of a marketable size. There were low numbers of first-generation flies caught from early November to late December, and very high numbers of third-generation flies caught from late March to late June. An early sowing (October) in combination with a harvest before the peak of third-generation flight activity (mid April-early May) resulted in a higher proportion of marketable carrots.

DIMBOA glucoside (2-O-/gb-D-glucopyranosyl-4-hydroxy-7-meth-oxy-1,4-benzoxazin-3-one), the main hydroxamic acid (Hx) in intact wheat plants, was detected in the honey dew ofRhopalosiphum padi feeding on seedlings of six wheat cultivars that differed in their concentration of Hx, suggesting that the chemical circulates in the phloem. Neither the aglucone (DIMBOA) nor its main breakdown product were found in any of the honeydew samples. Honey dew production by aphids caged on seedlings of the wheat cultivars and DIMBOA glucoside concentrations in the honeydew followed biphasic curves when plotted against Hx concentration, suggesting passive ingestion of the chemical from the phloem at low Hx concentrations and limited ingestion due to feeding deterrency by Hx in mesophyll cells at high Hx concentrations. The presence of plant toxins such as Hx glucosides in the phloem sap, the main ingesta of aphids, and in the mesophyll cells, has major implications for plant defense, through a feeding deterrent effect during stylet penetration, and deterrency (antixenosis) along with antibiosis during feeding.

From a previous worldwide screen of wheat cultivars as seedings, five were selected to encompass a wide concentraiton range of the hydroxaminc acid DIMBOA (0.99-8.07 mmol Kg -1fr. wt). Compared with those in seedings, the concentrations of DIMBOA in flag leaves of the same cultivars were relatively low (0.06-0.87 mmol kg-1fr. wt). Concentraions of hydroxamic acids in whole ears at anthesis and the early milk stage were even lower, ranging from undetectable to 0.05 mmol kg-1fr. wt. The three-day mean relaive growth rate (MRGR) was determined for nymphs of Sitobion avenace on the flag leaf (GS 39) and on the ear (GS 60-60) of the five cultivars. No significant differences in MRGR were found between cultivatrs at the same growth stage, although MRGR was higher on ears on than on flag leaces. The results are discussed in realtion to the potential of hydroxamic acids in programmses aimed at breeding mature-plant aphid resistance into wheat cultivars.

The abundance and ecological diversity of selected groups of beneficial arthropods were compared between 16 organic and 17 conventional carrot (Daucus carota L.) fields in the Manawatu (North Island) and Canterbury and Nelson (South Island) areas of New Zealand using a suction sampler. Organic fields had significantly higher numbers of Hymenoptera: Parasitica, Staphylinidae (Coleoptera), and Neuroptera (Hemerobiidae) compared with conventional fields. Organic fields also had a significantly more diverse predatory and parasitic community than did conventional fields, as measured by the “Sequential Comparison Index”. The implications of these results for biological control of pests in conventional and organic crops are discussed.

Three scales of wound-induced chemical responses in plants are identified: (1) highly localised chemical changes associated with disruption of cell compartmentation; (2) changes induced in cells surrounding the damaged area, forming a kind of halo around the damage, and (3) more widely-dispersed changes which may affect an entire organ, branch or plant. A brief review of the literature reveals that such chemical responses are very widespread in plants, and many of the substances formed are known to affect adversely the growth, development, or reproduction of insects. It is argued that wound-induced changes in plant chemistry represent for insects a powerful selective pressure for the dispersal of grazing. Levels and patterns of invertebrate grazing in a range of herbaceous and deciduous woody plants sampled at the end of the growing seasons were examined. Leaves of many species exhibited a strikingly evident over-dispersion of grazing initiations, and in some cases the arrangement of holes appeared close to regularity. The pattern of damage between leaves was, in most cases, heavily biased towards a large proportion of leaves receiving a low level of grazing. These highly dispersed patterns of grazing damage are consistent with the hypothesis that wound-induced responses play an important role in determining patterns of insect feeding. They have important implications for the expected levels of insect exploitation of host plants and for the advantages to the plant of distributing grazing damage evenly through the canopy.

Leaves of Betula were damaged artificially in April, June and August 1982. Palatability of damaged and adjacent undamaged leaves was assessed against controls in bioassays using the polyphagous Lepidoptera Spodoptera littoralis and Orgyia antiqua. Assessments were carried out at intervals from six hours to five months following each damage date. Palatability (relative proportions of leaves consumed) was significantly lower than controls in damaged and adjacent leaves after six hours and remained detectable for up to two months but this was less clear in the June-damaged samples and undetectable in the August group. Adjacent leaves were significantly affected whether distal or proximal to the damaged leaves. Marked and significant changes occurred in levels of soluble tannins in the damaged and adjacent leaves but the relationship between crude tannin levels and changed palatability was not simple cause and effect. No significant effects of damage on aphid (Euceraphis punctipennis) reproduction could be detected among birches in a growth room experiment in which half the trees were artificially damaged and half were controls. The results are discussed in the light of earlier work on induced defence in birch and five areas of significant new information represented by the results in this paper are identified.

Several studies have shown changes in the patterns of damage from feeding insects associated with changes in palatability and overall consumption as a result of wound-induced chemical changes in plants. This paper describes how the pattern of feeding damage made by the larvae of Spodoptera littoralis Boisd. (Lepidoptera: Noctuidae) on tomato is affected by changes in palatability of the leaves. Two sorts of responses to leaves from plants that had received prior damage were observed. Larvae offered a choice of leaves tended to take fewer meals on leaves from previously-wounded plants than on control leaves, frequently rejecting the former after sampling them. On wounded plants this rejection behaviour was associated with a shift in feeding site towards the base of the plant. However, starved larvae offered only a single excised leaf readily ate leaves from wounded plants but took shorter meals on these leaves than on controls. Although it was not directly tested it is possible that this difference in response reflected changes in food selectivity with a differing level of satiation. The results are considered in relation to the adaptive significance of the plant of changes in within-plant distributions of herbivore damage.

The phenology and sex ratios of three hover fly species on Canterbury farmland, New Zealand were recorded weekly from five yellow water-traps from October 15, 1993 to January 31, 1997. Gut fullness, egg number and pollen content were recorded weekly from September 8, 1994 to July 25, 1996. Catches of Melanostoma fasciatum (Mac-quart) and Melangyna novaezelandiae (Macquart) were higher during the summer months, with maximum male M. fasciatum catches at 0.7 per trap/day in January, 1997. Catches of female Eristalis tenax L. peaked at 0.24 in August, 1994. Gut fullness and egg number in M. novaezelandiae and M. fasciatum were low from June to September, 1995, a pattern opposite to that of E. tenax. For all species combined, gut fullness was significantly higher in gravid females compared with non-gravid females, and males. Thirty-nine different pollen types were recorded from all hover fly classes. Male E. tenax (the largest of the three species) consumed the widest range of pollen in summer and autumn whereas females consumed the widest range in winter and spring, a pattern opposite to that of M. novaezelandiae. The value of the work in possible population enhancement programmes for hover flies in crops is discussed.

Populations of the endangered weevil Hadramphus spinipennis (Coleoptera: Curculionidae), endemic to the New Zealand Chatham Is, were sampled five times from December 1993 to January 1997. All stages of its life cycle were closely associated with its host plant, the Chatham Is. endemic Aciphylla dieffenbachii (Apiaceae). Adult weevils were found throughout the year, predominantly on male A. dieffenbachii plants where they fed on foliage and flowers. Copulation took place from September to March, mostly on male flowers. Eggs were laid in the soil under host plants from September to April/May. The five larval instars fed on the roots, and pupation took place in the soil. In shadehouse studies, the shortest period from neonate to pupa was 147 days and pupation took less than 30 days. Field and laboratory data suggested that eggs laid early in spring developed into adults by early autumn, but that those laid in late summer overwintered as larvae and pupated the following spring. There is one extended generation a year. Occasionally, adult weevils could also be found on Pseudopanax chathamicum, but clearly preferred A. dieffenbachia in 'choice feeding tests'. No larvae were found on the roots of P. chathamicum. To secure the long-term survival of H. spinipennis, a third viable population is considered necessary. We suggest a survey of other islands for Hadramphus and/or the establishment of a third population.

Extracts of the marine spongeAxinella polycapellacontain 1,2,4-trihydroxybenzene (1) and 2,2′,4,4′,5,5′-hexahydroxybiphenyl (3) as antimicrobial constituents. Methods of synthesizing3by, oxidative dimerization of1were examined.

By applying insecticides at lower rates of active ingredients per unit area, survival rates of the pests’ natural enemies can be enhanced, whereas pest mortality can remain high. The effects of reduced application rates of the insecticides lambda-cyhalothrin and dimethoate on the mortality of bird cherry-oat aphid, Rhopalosiphon padi (L.), and lacewing Micromus tasmaniae Walker were determined in the laboratory and field. Cholinesterase (ChE) and glutathione S-transferase (GST) activities in survivors provided a measure of sublethal effects and general fitness. In the laboratory, lacewings were less sensitive than aphids to both insecticides, and dimethoate was more toxic than lambda-cyhalothrin. However, these results could not be recreated in the field, in part due to very low recapture rates. In summary, lambda-cyhalothrin seemed to have no effect on aphids, but it was toxic to lacewings. Dimethoate was far less toxic in the field, but aphids were still more sensitive than were lacewings. Cholinesterase activity was reduced by dimethoate exposure in the laboratory in both species, but there were species-specific differences. Dimethoate and lambda-cyhalothrin had no effects on GST activity in either species. The high mortality rate for lacewings and aphids exposed to dimethoate in the field suggests that the application rate could be reduced to as low as 10% of that recommended by manufacturers, and this should still be highly efficacious against aphids, while protecting the predatory lacewing. Measurement of enzyme activity could provide a useful indicator of “fitness” of survivors.

Modified cry1Ca5 and cry1Ba1 genes, under the transcriptional control of a CaMV 35S promoter, were individually transferred into potato (Solanum tuberosumL.) cv. Iwa using Agrobacterium-mediated transformation. Thirty-six and thirty-eight independently derived cry1Ca5- and cry1Ba1-transgenic plants were regenerated respectively. Multiplex-PCR confirmed the presence of the nptII selectable marker gene and the specific crygene in all regenerated lines. In greenhouse experiments, approximately 90% of each transgenic population produced phenotypically normal plants. More than 90% of the cry1Ca5-transgenic lines gave 100% larval mortality of potato tuber moth (PTM), Phthorimaea operculella(Zeller), on excised greenhouse-grown leaf and tuber bioassays. In contrast, only 40–50% of the cry1Ba1-transgenic lines gave 50 to 100% of larval mortality of PTM using the same bioassays, although all lines except one significantly inhibited larval growth. Southern blot analysis for eight selected cry1Ca5-transgenic lines revealed that they contained 1 to 6 copies of the crygene. The amount of Cry1C protein, quantified by ELISA, ranged from 0.26 to 8.42 μg per g of leaf tissue and from 0.23 to 1.02 μg per g of tuber tissue. No relationship was apparent between cry1Ca5 gene copy number and amount of Cry protein expressed in leaves and tubers. Southern blot analysis for seven selected cry1Ba1-transgenic lines revealed that they contained 2 to 8 copies of the cry1Ba1 gene. Both the cry1Ca5 and cry1Ba1 genes offer additional sources of resistance that can be deployed with other effective crygenes to control tuber moth in potatoes.

The use of insectary plants in agroecosystems to provide floral resources for enhancing natural enemy activity is an increasingly used practice, but candidate flowering plant species are not always screened for their attractiveness to key arthropods in the system being studied. In the work presented here, the relative attractiveness of four species of insectary plants to beneficial and pest insect species was assessed by observing the relative frequencies of flower visits to replicated blocks of the insectary flowers in two Oregon broccoli fields. The four plant species tested were alyssum (Lobularia maritima L. Desv.), coriander (Coriandrum sativa L.), buckwheat (Fagopyrum esculentum Moench), and phacelia (Phacelia tanacetifolia Benth.). Predatory hoverflies (Syrphidae) were identified to species, where possible, because of their previously observed importance as aphid predators in broccoli fields in the study area. The other beneficial insect groups observed were in the families Apidae, Coccinellidae, Tachinidae, and Vespidae, and the three main pest species were western tarnished plant bug (Lygus hesperus Knight), western spotted cucumber beetle (Diabrotica undecimpunctata undecimpunctata Mannerheim), and imported cabbageworm (Pieris rapae L.). The Syrphidae visited mostly coriander, but this “preference” was probably influenced by competition from other foragers. Bumblebees and the three pest species visited mostly phacelia, and other species groups were less consistent in their flower choices. The different insect preferences for flowers are discussed in terms of the key influencing factors that should be considered when assessing the relative attractiveness of insectary plants in the field.

Field Methods for the Study of Environmental Effects of Pesticides. Edited by M.P. Greaves, P.W. Greig-Smith & B.D. Smith, 1988. Monograph No. 40 of the British Crop Protection Council, Thornton Heath. 370 pp. Price £20.00 (overseas £25.00). S.D. WrattenForm and Function in Birds. Volume 4. Edited by A.S. King & J. McLelland, 1989. Academic Press, London. 591 pp. Price £89.00. Peter Lack