Ingestion of spinosad bait GF-120 and resulting impact on adult Chrysoperla carnea (Neuroptera: Chrysopidae)

The spinosad bait spray GF-120 Naturalyte F® (Dow AgroSciences LLC, Indianapolis, IN, USA) is widely used in commercial olives in California. Because of concern about its non-target effects on beneficial insects, we studied its impact on feeding behavior, mortality, and reproductive parameters of adult green lacewings, Chrysoperla carnea (Stephens), under laboratory conditions. Male and female feeding rate and quantity, and subsequent mortality, were compared over a 5-day period following a 24-h exposure to honey, GF-120, or the bait component (without spinosad) in two-choice and no-choice assays. All treatments were ingested equally when offered alone. Spinosad did not impart repellency or preference to GF-120 relative to the bait. Honey was preferred in choice tests with GF-120 or bait. Significant mortality occurred when GF-120 was offered alone, but was not significant when it was offered in choice with honey or bait. In a separate assay of female longevity and reproduction, mortality rate as a function of time was similar in all treatments, except for some significantly earlier mortality due to GF-120 compared with honey. GF-120 ingestion significantly reduced fecundity compared with bait during the first week after treatment. Egg hatch was not significantly affected. The preference of adult C. carnea for food should ameliorate the potential negative effect of GF-120 on adult C. carnea mortality in the field. The laboratory study finds that GF-120 is a potentially safer choice for C. carnea than an aqueous suspension of spinosad, and provides no new evidence for definitive risk to field populations.     

Resistance,its stability and reversion rate of resistance to imidacloprid,indoxacarb and chlorfenapyr in a field population of green lacewing Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae)

Abstract

Green lacewing, Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae) is a valuable bio-control agent that predates over various insect pests with high efficacy. It has developed considerable resistance to different classes of insecticides. This study was planned to investigate resistance level, stability and reversion rate against some new chemical insecticides using a field collected population of C. carnea. Field collected strain of C. carnea showed 313.44-fold, 216.50-fold and 276.83-fold resistance to imidacloprid, indoxacarb and chlorfenapyr compared to susceptible population, respectively. Baseline susceptibility values of C. carnea to imidacloprid, indoxacarb and chlorfenapyr were 2627.31, 502.10 and 581.89?ppm, while the insecticide resistance decrease rate was ?0.039, ?0.048 and ?0.040, respectively. Rotation of these insecticides requires quality measures maintaining survival of C. carnea in an intense environment where repeated applications are required to avoid economic damage by pests.     

Post-exposure temperature influence on the toxicity of conventional and new chemistry insecticides to green lacewing Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae)

Chrysoperla carnea (Stephens) is an important biological control agent currently being used in many integrated pest management (IPM) programs to control insect pests. The effect of post-treatment temperature on insecticide toxicity of a spinosyn (spinosad), pyrethroid (lambda cyhalothrin), organophosphate (chlorpyrifos) and new chemistry (acetamiprid) to C. carnea larvae was investigated under laboratory conditions. Temperature coefficients of each insecticide tested were evaluated. From 20 to 40 °C, toxicity of lambda cyhalothrin and spinosad decreased by 2.15- and 1.87-fold while toxicity of acetamiprid and chlorpyrifos increased by 2.00 and 1.79-fold, respectively. The study demonstrates that pesticide effectiveness may vary according to environmental conditions. In cropping systems where multiple insecticide products are used, attention should be given to temperature variation as a key factor in making pest management strategies safer for biological control agents. Insecticides with a negative temperature coefficient may play a constructive role to conserve C. carnea populations.     

Prey-mediated effects of Cry1Ab toxin and protoxin and Cry2A protoxin on the predator Chrysoperla carnea

Laboratory feeding experiments were carried out to study prey-mediated effects of artificial diet containing Bacillus thuringiensis proteins on immature Chrysoperla carnea. Activated Cry1Ab toxin and the protoxins of Cry1Ab and Cry2A were mixed into standard meridic diet for Spodoptera littoralis (Boisduval) larvae at the following concentrations; for Cry1Ab toxin, 25, 50, 100 g g^–1 diet were used; for Cry1Ab protoxin, the concentration was doubled (50 g g^–1 diet, 100 g g^–1 diet and 200 g g^–1 diet) to give relative comparable levels of toxin concentration. Cry2A protoxin was incorporated into the meridic diet at one concentration only (100 g g^–1 diet). For the untreated control, the equivalent amount of double distilled water was added to the meridic diet. Individual C. carnea larvae were raised on S. littoralis larvae fed with one of the respective treated meridic diets described above. The objectives were to quantify and compare the resulting effects on mortality and development time of C. carnea with those observed in two previous studies investigating prey-mediated effects of transgenic Cry1Ab toxin-producing corn plants and the other studying effects of Cry1Ab toxin fed directly to C. carnea larvae. Mean total immature mortality for chrysopid larvae reared on B. thuringiensis-fed prey was always significantly higher than in the control (26%). Total immature mortality of C. carnea reared on Cry1Ab toxin 100 g g^–1 diet-fed prey was highest (78%) and declined with decreasing toxin concentration. Cry1Ab protoxin-exposed C. carnea larvae did not exhibit a dose response. Prey-mediated total mortality of Cry1Ab protoxin-exposed chrysopid larvae was intermediate (46–62%) to Cry1Ab toxin exposed (55–78%) and Cry2A protoxin (47%) exposed C. carnea. In agreement with the previous studies, total development time of C. carnea was not consistently, significantly affected by the Bt-treatments except at the highest Cry1Ab toxin concentration. However, both highest mortality and delayed development of immature C. carnea raised on Cry1Ab toxin 100 g g^–1 diet – fed prey may have been confounded with an increased intoxication of S. littoralis larvae that was observed at that concentration. At all other B. thuringiensis protein concentrations S. littoralis was not lethally affected. Comparative analysis of the results of this study with those of the two previous studies revealed that in addition to prey/herbivore by B. thuringiensis interactions, also prey/herbivore by plant interactions exist that contribute to the observed toxicity of B. thuringiensis – fed S. littoralis larvae for C. carnea. These findings demonstrate that tritrophic level studies are necessary to assess the long-term compatibility of insecticidal plants with important natural enemies.     

Relative consumption of three aphid species by the lacewing, Chrysoperla rufilabris, and effects on its development and survival

Relative consumption of three aphid species, Aphis gossypii Glover, Myzus persicae (Sulzer) and Lipaphis erysimi (Kaltenbach) (Homoptera: Aphididae), by larvae of the lacewing, Chrysoperla rufilabris (Burmeister) (Neuroptera: Chrysopidae), was determined in the laboratory, together with effects on lacewing development and survival. Percentages of survival of C. rufilabris from first instar to adult eclosion were significantly different among lacewing larvae fed different aphid species. When larvae were fed A. gossypii and M. persicae, all larvae developed to adulthood. All larvae died prematurely when they were fed L. erysimi. Developmental duration of C. rufilabris larvae was significantly shorter when larvae were fed A. gossypii (18.0 d) than when larvae were fed M. persicae (19.2 d). The number of fourth instar aphids consumed during development by C. rufilabris larvae differed significantly among individuals fed different aphid species. Chrysoperla rufilabris consumed an average of 168 M. persicae, followed by 141.6 A. gossypii, and only 26.6 L. erysimi. The percentage of these total number of aphids consumed by each larval stadium of C. rufilabris varied significantly among aphid species. The percentage of A. gossypii consumed by each larval stadium was similar to that for M. persicae, 12.1 and 11.4% by the first instar, 15.7 and 13.1% by the second instar, and 72.2 and 75.5% by the third instar, respectively; whereas in the case of L. erysimi, 23.3% of the total number of aphids were consumed by the first instar, 30.1% by the second instar, and 46.6% by the third instar.     

The effects of different components of an artificial food on adult green lacewing (Chrysoperla carnea) fecundity and longevity

Artificial foods comprising yeast products, sugar and water are often sprayed in the field to increase numbers of naturally occurring lacewing populations. The relative importance of the components of these foods for green lacewing (Chrysoperla carnea Stephens) fecundity and longevity is investigated in this paper. In laboratory experiments insects receiving only sugar solution lived significantly longer than those receiving diets containing both sugar and yeast (P<0.05). The inclusion of yeast is required for egg production, but few eggs are produced on yeast solution alone. For maximum egg production, food containing yeast and sugar must be offered on more than one occasion. Compared with insects given a diet comprising yeast autolysate, sugar, and water in the ratios 4∶7∶10, small but significant reductions in egg production rate were noted when the amount of either the yeast, or both the yeast and the sugar, was halved. The implication of these findings for the field is that viscous foods must be offered on a regular basis for maximum effectivity.     

Sublethal effects of D-limonene on the cat flea,Ctenocephalides felis

Fleas (Ctenocephalides felis Bouché) that survived an LC 75 treatment with D-limonene had reduced fecundity. When put on hosts after exposure to D-limonene, they had higher mortality rates than control fleas and did not lay any eggs. D-limonene treated fleas also produced less feces and probably fed less while on their hosts.

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Effet sublétal du D-limonène surCtenocephalides felis

Résumé Les puces,C. felis Boucheé, qui ont survécu à 75% de la dose létale de D-limonène, ont présenté une fécondité reduite, lorsqu'elles ont été placées sur des chats. Le résultat a été observé en plaçant les puces traitées et les témoins dans des cages fixées par des angles sur les chats. Chaque 24 heures, le nombre d'oeufs, la quantité d'excréments, et le nombre de puces mortes ont été notés. Les puces traitées au D-limonène avaient une mortalité plus élevée que les témoins: au bout de 72 h, 98.3% des puces traitées étaient mortes contre 28.3% pour les témoins. Les puces traitées ont produit moins d'excréments et ont probablement consommé moins sur leurs hôtes; elles n'ont pas pondu. Ces données suggèrent que même si toutes les puces ne sont pas tuées par le traitement, avec le D-limonène, d'un chat contaminé, les survivantes ne peuvent pas se reproduire et ne doivent pas provoquer autant d'irritation, puisque leur alimentation est réduite.

     

Utility of mobile, field-based artificial streams for assessing effects of pulp mill effluents on fish in the Canadian environmental effects monitoring (EEM) program

Although the utility of artificial streams(mesocosms) as research tools for assessingeffects of contaminants on aquatic biota hasbeen recognized, their use in regulatoryprograms has been limited. We conducted threestudies to examine the utility of using mobile,field-based artificial streams to assess theeffects of pulp and paper effluents on fish asrequired in the Canadian Environmental EffectsMonitoring (EEM) program. When evaluatedagainst criteria of environmental relevance,interpretability, scientific defensibility, andcost-effectiveness, mesocosms satisfied allcriteria. Measured endpoints on fish survival,energy use (growth, gonad size) and energystorage (liver size, condition) were relevantto the detection and quantification of effluenteffects on fish. Response patterns were similarto those reported in the literature for fieldsurveys showing reduced gonad size andincreased liver size in adult mummichog (Fundulus heteroclitus) and decreased growth ofjuveniles. The flexibility of the systems tomeasure effects in multiple, replicatedtreatments under controlled effluent exposureand ambient conditions of water quality,temperature and photoperiod provided data thatcould not be obtained at these sites usingfield assessment approaches. The repeatabilityof using the same mobile, mesocosm system ofuniform design and operation at different millsites and for different receiving environmentswas unique and contributed to consistentscientific evaluation and interpretation. Thesestudies demonstrated that mesocosms producedgood quality data that fit within the requiredregulatory context of the Canadian EEM program.     

Phylogeny of the green lacewing Chrysoperla nipponensis species‐complex (Neuroptera: Chrysopidae) in China,based on mitochondrial sequences and AFLP data

Abstract Several studies have indicated that the green lacewing, Chrysoperla nipponensis (Neuroptera: Chrysopidae) may include more than one valid species. We investigated the phylogenetic status of Chrysoperla nipponensis s.l. in China and Japan using mitochondrial sequences and AFLP data. The molecular phylogenetic analyses based on mitochondrial genes showed that the C. nipponensis species‐complex comprises four clades, each having high support values. In addition, the phylogenetic tree based on AFLP data indicates that the species‐complex comprises three groups. These results confirm that C. nipponensis s.l. comprises at least three genetically distinct clades and suggests that two of these clades may be closely related to populations of C. nipponensis in Japan. However, these clades cannot be recognized as species until analysis of their courtship songs has been completed.     

Characterizing indirect prey-quality mediated effects of a Bt crop on predatory larvae of the green lacewing, Chrysoperla carnea

There is increasing evidence that insecticidal transgenic crops can indirectly cause detrimental effects on arthropod predators or parasitoids when they prey on or parasitize sublethally affected herbivores. Our studies revealed that Chrysoperla carnea is negatively affected when fed Bt-susceptible but not Cry1Ac-resistant Helicoverpa armigera larvae that had fed Bt-transgenic cotton expressing Cry1Ac. This despite the fact that the predators ingested 3.5 times more Cry1Ac when consuming the resistant caterpillars. In order to detect potential differences in the nutrient composition of prey larvae, we evaluated the glycogen and lipid content plus the sugar and free amino acid content and composition of caterpillars fed non-Bt and Bt cotton. The only change in susceptible H. armigera larvae attributable to Bt cotton feeding were changes in sugar concentration and composition. In case of the Cry1Ac-resistant H. armigera strain, feeding on Bt cotton resulted in a reduced glycogen content in the caterpillars. The predators, however, appeared to compensate for the reduced carbohydrate content of the prey by increasing biomass uptake which caused an excess intake of the other analyzed nutritional compounds. Our study clearly proves that nutritional prey-quality factors other then the Bt protein underlie the observed negative effects when C. carnea larvae are fed with Bt cotton-fed prey. Possible factors were an altered sugar composition or fitness costs associated with the excess intake of other nutrients.     

Resource limitation and the lethal and sublethal effects of a viral pathogen in the Indian meal moth, Plodia interpunctella

Abstract.

• 1 The effects of resource limitation and the lethal and sublethal effects of a granulosis virus on a lepidopteran host, the Indian meal moth, Plodia interpunctella, were examined.
• 2 The food quality was manipulated by the addition of an inert bulking agent (methyl cellulose) which caused the size, development rate and fecundity of the moths to be reduced.
• 3 The resource quality had no effect on the mortality due to the virus. In contrast, sublethal effects of the virus on pupal weight were more apparent under conditions of resource limitation.
• 4 Considerable variation between the sublethal effects after challenge with different doses of the virus was found. The balance between deleterious sublethal effects of the virus and the selection of more robust individuals by the bioassays is proposed as a mechanism to explain this variation.
• 5 Implications for the dynamics of insect hosts and their pathogens are discussed.

     

Sublethal effects of insecticides on the intrinsic rate of increase of cotton aphid

Insecticides are often implicated in causing outbreaks of the cotton aphid, Aphis gossypii (Glover) (Homoptera: Aphididae), through stimulation of reproduction. In this study we report the sublethal effects of dosages of bifenthrin, acephate, carbofuran or pyriproxifen on cotton aphid reproduction. We could not detect any increase or decrease in the intrinsic rate of increase of cotton aphids exposed to bifenthrin, acephate or carbofuran. However, we did detect some increases in the net reproductive rate of aphids treated with bifenthrin justifying further investigation of the effect on reproduction by this insecticide. Trends based on simple linear regression models suggest that sublethal dosages of bifenthrin or carbofuran have a negative impact on aphid population growth as dosages increase. These data suggest that stimulation of reproduction by these insecticides probably does not play a major role in cotton aphid outbreaks or resurgence. Pyriproxyfen is a juvenoid currently used for control of whiteflies in cotton. It demonstrated significant activity towards cotton aphid reared on treated cotton in our bioassays. Pyriproxyfen caused sterility in most aphids exposed to dosages exceeding 1 ppm, and reduced aphid longevity by approximately 50%. However, it did not appear to greatly influence the reproductive potential or longevity of reproductively mature aphids. A field study indicates that pyriproxyfen affects cotton aphid population structure and may have potential in managing cotton aphid outbreaks. Modifying aphid population structure and growth through the use of juvenoids such as pyriproxifen may prove to be an effective proactive approach to pest control without adversely impacting beneficial organisms or causing pest resurgence.     

Fluoride effects on leaf cell ultrastructure of olive trees growing in the vicinity of the Aluminium Factory of Greece

Summary Leaves of olive trees growing in the vicinity of the Aluminium Factory of Greece were ultrastructurally investigated in order to determine any malformations caused by environmental air pollutants, especially hydrogen fluoride, in comparison with control samples and normal seasonal senescence. Estimation of some elements accumulated by these leaves showed that they contained high amounts of F and Al attributable to the operation of the nearby factory. The most seriously effected cell components were found to be the mesophyll chloroplasts that show a dilation of the intrathylakoid space, increase of the number of plastoglobuli, discoloration of plastoglobuli, accumulation of large starch grains and an overall disorganized appearance of the organelle. The nuclear crystalloid inclusions have unusual shapes, while the vacuoles contain a fibrillar/granular material that increases their electron density. It is concluded that the ultrastructural malformations are caused by a combination of environmental stresses and air pollutants.This paper is dedicated to Professor Dr. Eberhard Schnepf on the occasion of his 60^th birthday.     

Irrigation effects on daily and seasonal variations of trunk sap flow and leaf water relations in olive trees

Irrigation effects on whole-plant sap flow and leaf-level water relations were characterised throughout a growing season in an experimental olive (Olea europaea L.) orchard. Atmospheric evaporative demand and soil moisture conditions for irrigated and non-irrigated olive trees were also monitored. Whole-plant water use in field-grown irrigated and rain fed olive trees was determined using a xylem sap flow method (compensation heat-pulse velocity). Foliage gas exchange and water potentials were determined throughout the experimental period. Physiological parameters responded diurnally and seasonally to variations in tree water status, soil moisture conditions and atmospheric evaporative demand. There was a considerable degree of agreement between daily transpiration deduced from heat-pulse velocity and that determined by calibration using the Penman–Monteith equation in the field. Summer drought caused decreasing leaf gas exchange and water potentials, and a progressive increase in hydraulic conductance (stronger in non-irrigated than irrigated trees), probably attributable to modifications in hydraulic properties at the soil-root interface. Negligible hysteresis, attributable to low plant capacitance, was observed in the relationship between leaf water potential and sap flow. A proportional decrease in maximum daily leaf conductance with increasing vapour pressure deficit was observed, while mean daytime canopy stomatal conductance decreased with the season. As a result, plant water use was limited and excessive drought stress prevented. Non-irrigated olive trees recovered after the summer drought, showing a physiological behaviour similar to that of irrigated trees. In addition to physiological and environmental factors, there are endogenous keys (chemical signals) influencing leaf level parameters. Olive trees are confirmed to be economical and sparing users of soil water, with an efficient xylem sap transport, maintenance of significant gas exchange and transpiration, even during drought stress.     

Sublethal insecticide effects on the probing responsiveness of tsetse flies and blowflies

ABSTRACT. Tethered Glossina austeni Newst. males and females were tested for daily and starvation-related changes in their probing responsiveness to a warmed sponge surface presented to their tarsi. The change in responsiveness of the two sexes was indistinguishable, both following a marked V-shape pattern across the photophase of LD 12:12 and an increase from a mean of c. 5% responding on day 3 after a blood-meal to over 60% doing so on day 6. Sublethal doses ( c. LD₁₅) of endosulfan had no detectable effect on this pattern, but of DDT caused a temporary doubling of responsiveness, and of permethrin caused a marked and long-lasting reduction in responsiveness. Tethered Protophormia terraenovae (R.-D.) tested similarly for changes in threshold to tarsal stimulation with sucrose solutions (assessed by whether or not they extended the proboscis), showed a marked threshold decrease following LD₁₅ diazinon treatment and, like the tsetse, no effect of LD₁₅ endosulfan treatment, though unlike tsetse they showed no increase in threshold following permethrin treatment. The results are discussed in relation to what is known of the mode of action of these four insecticides, and in relation to circadian rhythm physiology in insects.     

甲氧虫酰肼对棉铃虫生长发育的亚致死效应研究

以一个对甲氧虫酰肼具有18.5倍抗性的棉铃虫Helicoverpa armigera(Hübner)种群(R)和其同源对照种群(S)为对象,研究了甲氧虫酰肼对棉铃虫生长发育的亚致死效应。结果表明,甲氧虫酰肼亚致死剂量(LC25)处理R和S种群的3龄初幼虫,对S种群幼虫的生长抑制率(37.30%)显著大于R种群(21.20%)。与空白对照处理相比,致死剂量处理R和S种群后,均表现出生长发育延缓,蛹期延长,化蛹率、羽化率、卵孵化率降低,且对S种群的影响更明显。研究结果表明亚致死剂量的甲氧虫酰肼对棉铃虫存在一定的不利影响,但对甲氧虫酰肼具有一定抗性的棉铃虫种群能够减轻这种不利影响。     

Effect of relative humidity on development, survival and reproduction of the predatory lacewing Dichochrysa prasina (Neuroptera: Chrysopidae)

The effect of five constant relative humidity (RH) regimes (12%, 33%, 55%, 75% and 94%) on the preimaginal development and adult longevity and reproduction of Dichochrysa prasina Burmeister was studied at 26 ± 1 °C and a photoperiod of 16:8 (L:D) under laboratory conditions. For the experiments, larvae were fed individually on eggs of the flour moth Ephestia kuehniella (Zeller), whereas adults on a liquid diet consisting of water, yeast hydrolysate, sugar and honey. The experimental insects were maintained individually in sealed plastic containers with saturated water salt solutions at the base to control RH. Preimaginal developmental time from egg to adult for females and males was significantly shorter at 75% and 94% RHs than at other RHs in the range from 12% to 55%. Percentages of adult emergence were similar at all RHs tested and varied from 52.5% to 75.0%. Adult females that had no access to water and were maintained at 12%–75% RH lived on average less than two weeks and laid no eggs, whereas at 94% RH they lived longer and each laid on average 201 eggs. When the females had periodic access to a water source a significant increase in both longevity and egg production occurred and the estimated intrinsic rate of increase was high, irrespective of RH. These results could be useful for the mass-rearing of D. prasina and for better understanding its population dynamics under field conditions.     

Some effects of plant ash on the chemical properties of soils and aqueous suspensions

Summary Laboratory studies indicate that percolation of water through accretions of plant ash will markedly increase the pH of solutions entering the underlying soil. Ash derived from graminaceous straws raised the pH of an aqueous suspension (1 g ash: 500 ml H₂O) to 10.6, compared to 9.3 for a saturated solution of CaCO₃. However, on a weight basis these ashes possess only approximately 5–15% of the alkalising power of CaCO₃ in terms of their ability to neutralise acid or elevate soil pH. The effect of ash on soil pH, and pH dependent soil properties, is determined by the amount and composition of the ash deposited and on the buffering capacity of the soil.High field rates (2480–6750 kg ha^–1) of ash added to a podzolic soil increased the pH of the soil solution by up to 3 units. A pH rise of 1 unit is sufficient to increase the solubility of native soil organic carbon (O.C.) in water (i.e. mobilize readily metabolizable microbial substrate) and stimulate respiration rate.In more strongly buffered krasnozem soil, maximum rise in pH of the soil solution did not exceed 0.7 unit. However, even such small pH shifts significantly reduced the solubility of soil O.C. in water; probably by changing the character (and hence solubility) of organo-mineral chelation complexes. High rates of ash application also slightly decreased respiration rate in this soil type.The application of neutralized ash, which added metal ions to the soil solution, had a similar but smaller effect to unneutralized ash on the solubility of soil O.C. in podzolic soil, but little effect in krasnozem soil.     

Investigating the effects of crop type, fertility management and crop protection on the activity of beneficial invertebrates in an extensive farm management comparison trial

The activity of 11 groups of invertebrates, mainly predators and parasites, was investigated in 2005 and 2006 in a plot trial system on a farm in northern England, where the effects of organic and conventional fertility and crop protection management were separated within different crop types. Invertebrate activity was assessed using pitfall traps and suction sampling. Mixed effects models indicated that crop type significantly affected activity in all 11 groups. Crop protection applications had only a limited impact on activity but fertility management had considerable effects in some crops. Most differences were in barley, wheat and grass/clover, with less in vegetable and bean plots. Carabidae, Lycosidae, Staphylinidae, Linyphiidae and Braconidae gave consistent responses to fertility management, with more activity of the first two groups in organic plots and more of the other three in conventional plots. However, Coccinellidae and Ichneumonidae were not consistent in their activity between crops. After the effects of crop type had been partialled out, a constrained ordination showed that the novel combination of organic fertility and conventional crop protection had the most influence on group activity, with the combination of organic fertility and organic crop protection also significant. Maximising the activity of beneficial invertebrates in organic and sustainable farming systems requires a basic understanding of the effects of both crop type and fertility management, as well as crop protection.