Integrated Pest Management Plots Research Articles

Impact of IPM practices on microbial population and disease development in transplanted and direct-seeded rice.

Integrated pest management (IPM) is a comprehensive approach to managing diseases, focusing on combining various strategies to reduce pathogen populations effectively and in an environmentally conscious way. We investigated the effects of IPM on beneficial microbial populations and its relationship with pathogen populations in both direct-seeded rice (DSR) and transplanted rice (TR) systems. This study demonstrates that IPM practices have significantly higher populations of beneficial microbes, such as Trichoderma harzianum and Pseudomonas fluorescens, and lower level of the pathogen Fusarium verticillioides compared to non-IPM (farmer practices). The average mean population of T. harzianum was 6.38 × 103 CFU/g in IPM compared to 3.22 × 103 CFU/g in non-IPM during 2019 in TR at Bambawad. P. fluorescens mean population in 2019 was significantly higher in IPM (4.67 × 103 CFU/g) than in non-IPM (3.82 × 103 CFU/g) at the Karnal location in DSR. The F. verticillioides populations were significantly lower in IPM fields (9.46 × 103 CFU/g) compared to non-IPM fields (11.48 × 103 CFU/g) during 2017 at Haridwar in TR. Over three years, a significant increase in the populations of beneficial microbes in IPM plots was observed in all three locations of both TR and DSR, highlighting the sustainable impact of IPM practices. Disease dynamics analysis revealed that IPM effectively managed key diseases in both DSR and TR systems, with significant correlations between microbial density and disease severity. A significant positive correlation was recorded between F. verticillioides population and bakanae incidence at all three locations. Sheath blight incidence was negatively correlated with P. fluorescens population in both TR and DSR. In DSR, bacterial blight and brown spot diseases are reduced with the increased population of T. harzianum. Bioagents T. harzianum and P. fluorescens reduced disease incidence, underscoring the role of beneficial microbes in disease suppression and their importance for sustainable production using IPM practices.

Validation and implementation of principles of the Integrated Pest Management concept - sustainability and current challenges in pest endemic pulse bowl of India

Insect pests and vascular diseases are the major constraints to pigeonpea production in Karnataka and primarily responsible for lower productivity. There is no substantial host plant resistance to key insect pests in currently adopted cultivars, however effective utilization of other components of pest management led to development of various integrated pest management (IPM) to minimize yield losses and protect the environment. In present studies, it is a total “system approach” to sustainable pest management involving seed treatment with microbials, synchronized sowing, modification in landscape and application of need-based pesticide spray. Spray schedule was combined with online pest monitoring system for the plant protection related advisories for the target region. The resultant IPM package implemented through farmer-managed operational scale plots and compared with non-IPM (normal farmer practices) across 7 taluks of Gulbarga district for 4 years (2010–2013 seasons). A total of 2197 farmer-managed demonstrations were conducted, giving a 5–104% yield advantage (district means) of IPM over farmers’ practice. Pest incidence data in IPM vis-à-vis non-IPM clearly indicates that pest can be managed by adopting IPM technology. Number of spray of pesticides could be reduced from 6 to 4. Pesticide residue analysis for 102 chemical pesticides for representative soil, water and grain samples drawn from IPM as well as non-IPM (farmers’ practice) fields, indicates their presence within the prescribed limits. Grain yields in IPM plots were generally 15–20% higher than in FP. Even with all the available inputs, the production is subject to residual production risk due to abiotic constraints (rainfall), diseases and insect pests, which often large farmers are able to bear. Here in present studies it has been clearly demonstrated that strategies are friendly and adoptable by the small and marginal farmers. Effective implementation of IPM practices by participating farmers demonstrated that remunerative and reliable yields could be obtained in this pest-prone environment and helps mitigate climate induced threat to agricultural development having relevance to other pigeonpea growing regions prone to similar pest pests.

Economic Benefits from the Use of Mass Trapping in the Management of Diamondback Moth, Plutella xylostella, in Central America.

The diamondback moth, Plutella xylostella (L.), is a worldwide pest of brassica crops, resistant to a large number of insecticides. As an alternative, the use of pheromone-baited traps has been proposed but farmers are yet to be convinced. In the present study, we aimed to validate the benefits of the use of pheromone-baited traps for monitoring and mass trapping in cabbage production in Central America as means of Integrated Pest Management (IPM) in comparison to calendarized insecticide sprays, which are the farmers' current practices (FCP). Mass trapping was established in nine selected plots of cabbage in Costa Rica and Nicaragua. Average captures of males/trap/night, plant damage and net profits of these IPM plots were compared to simultaneously evaluated or historically reported FCP plots. The results indicate that in Costa Rica, trap captures did not justify the application of insecticides and average net profits increased by more than 11% when the trapping methods were implemented. In Nicaragua, IPM plots were able to reduce insecticide applications to one third of those in FCP plots. These results confirm the economic and environmental benefits of pheromone-based management of DBM in Central America.

Impact of integrated pest management (IPM) module on major insect-pests of wheat and their natural enemies in North-western plains of India

In order to sustain the wheat production in North-western plains of India, a study was conducted to test the integrated pest management (IPM) module with commonly used farmer’s practices for the management of insect pests during 2017-18 and 2018-19. It was observed that aphid population was significantly lower in IPM plot (2.48-2.60 aphids/tiller) as compared to farmer’s practices (13.93-16.46 aphids/tiller) at peak period of their activity. At the same time, the population of coccinellids predators was significantly higher in IPM plots (6.80 beetle/m2) as compared to non-IPM plots (1.26 beetles/m2) during 2017-18. The termite damage ranged from 2.48-2.96 per cent in farmer's practices while it was only 0.20-0.80 per cent in IPM fields. Similarly, greater pink stem borer (PSB) damage was recorded in farmer's practices (0.96-2.48 per cent) as compared to IPM fields (0.46-0.68 per cent). The incidence of brown wheat mite (BWM) was recorded on maturing wheat and it was 2-5 fold higher in farmer's practice (11.73-31.53 mites/10 cm2) as compared to IPM plots (4.20- 5.00 mites/10 cm2). Approximately 9 per cent increase in grain yield resulted in additional income of Rs. 9291/ha in IPM plot. Seed treatment, yellow sticky trap based monitoring of aphids and need based application of insecticide resulted in better control of insect. Doi.org/10.25174/2582-2675/2020/100185

Effects of barley yellow dwarf disease on wheat grain quality traits

AbstractBackground and objectivesBarley yellow dwarf (BYD) is an important aphid‐vectored viral disease of wheat. Grain samples were obtained from a previously reported integrated pest management (IPM) field plot experiment that was designed to test the effects of planting dates, cultivars, and insecticide treatments on BYD incidence and wheat yields over 4 years in Kansas, USA. In the current study, the effect of BYD on grain quality traits was estimated by comparing untreated plots that had varying levels of BYD to healthy control plots that received repeated insecticide treatments. Additional grain samples were compared from Tagged Tillers of visually healthy and symptomatic plants.FindingsFor IPM Plots, interactions between insecticide treatments and cultivars were not significant (α = 0.05). The effect of BYD on protein content (PC), starch content (SC), average kernel weight (AKW), and yield was a relative percent gain or loss of +3.7%, −1.0%, −6.4%, and −12.6%, respectively, averaged over all experimental factors and years. Linear critical point models were developed to estimate the percent gain or loss relative to healthy controls as a function of BYD incidence. For each percentage of BYD incidence, BYD increased PC by 0.284%, decreased SC by 0.063%, decreased AKW by 0.314%, and decreased grain yield by 0.664%. Similar magnitudes of effects of BYD were estimated from Tagged Tiller samples. There were distinct, non‐overlapping distributions for healthy versus symptomatic Tagged Tillers for PC and SC for four of six cultivars. However, two cultivars had overlapping distributions for healthy versus symptomatic samples, suggesting they had resistance or physiological tolerance to BYD.ConclusionsNatural infection with BYD significantly increased PC and decreased SC, AKW, and yields of wheat. The increase in PC was probably due to the concentrating effect of decreased SC and AKW. Critical point models were developed to predict the impact of varying levels of BYD on these parameters. Near‐infrared spectroscopy (NIRS) measurement of PC and SC of diseased versus healthy samples has potential to identify wheat lines with resistance or tolerance to BYD.Significance and noveltyThis is the first report of the effect of BYD on wheat starch content and confirms the effect on average kernel weight and protein content. This is the first report of simple models to predict grain quality changes as a function of BYD incidence. Near‐infrared spectroscopy (NIRS) measurement of grain PC and SC from plants with BYD may offer wheat breeding programs a rapid and objective selection method for improved resistance or physiological tolerance to BYD.

Validation of integrated pest management module against insect pests of pigeonpea, Cajanus cajan in Tarai region of Uttarakhand

Experiments on validation of integrated pest management (IPM) module against insect pest of pigeonpea in comparison with the Non-IPM (farmer’s practices) were conducted at N.E.B. Crop Research Centre, G. B. Pant University of Agriculture & Technology, Pantnagar during Kharif 2014 and 2015. Adopted IPM module contained Seed treatment with Trichoderma spp. @10g/kg of seed, Sole crop, Bird perches @ 50/ha, need based insecticides spray (Chlorantraniliprole 18.5SC @ 30 g a. i./ha; Neem soap@10g/lit; Acetamiprid 20SP @ 20 g a. i./ha). The results indicated that minimum population of pod borers (Helicoverpa armigera,Maruca vitrata and podfly) and sucking insects (aphids, jassids, pod bug) was reported in IPM plots and maximum population of insects was observed in Non-IPM plots. Percent insect control over non-IPM was 50.98 % for H. armigera, 44.69 % for M. vitrata and 19.17 % for Maruca webbing were recorded. While, for sucking pest complex, insect control over non-IPM was 51.59 %, 40.36 % and 36.17 % against jassids, aphids and tur pod bug, respectively. Similarly, minimum pod borer damage (6.48 and 7.71 %) was recorded in IPM plots as compared to maximum pod borer damage (8.37 and 8.22 %) in non-IPM plots, respectively during 2014 and 2015. Whereas, pooled grain yield for IPM plots was 1286.5 kg/ha for both seasons as against 888 kg/ha in non-IPM plots with 1:2.89 benefit cost ratio. Hence, It is apparent that studied IPM module was able to increase the yield of pigeonepea with lower cost of production as against non-IPM thus it would be benefiting the farmers.

Impact of Insecticide Applications on Arthropod Predators and Plant Feeders in Cambodian Rice Fields

Rice (Oryza sativa) is the staple crop of Cambodia. The heavy use of pesticides has caused significant financial losses to local farmers. This study examined the necessity and economic viability of insecticide use for rice cultivation, and the multiple interactions between the populations of both insect pests and natural enemies in dry-season rice fields. The outcomes of calendar-based insecticide-sprayed and non-sprayed rice fields were compared at three provincial research stations in Cambodia in terms of rice growth, economic returns, damage caused by insect pests, and population dynamics of insect pests and arthropod natural enemies. The results showed that rice fields without insecticide application did not suffer significant damage by insect pests or by diseases and had similar yields to those treated with insecticide application in two provinces. Although the occurrence of caseworm was observed in the third province, this was successfully controlled by an integrated pest management (IPM) treatment without using insecticides. Insufficient densities of natural enemies appeared to correlate with the caseworm outbreak in this location, whereas high densities of natural enemies relative to those of insect pests contributed to control potential pest expansion in the other two provinces. Natural enemy populations were significantly decreased by insecticide applications. Reduced insecticide input in the insecticide-free control and IPM plots resulted in higher net profits than those in insecticide-applied plots, except for plots in the region with a caseworm outbreak (insecticide-free). Overall, this study provides encouraging insight into cost effective and environmentally friendly pest management in Cambodian rice fields.

English

Participatory diagnostic farmer field fora (FFF) were conducted at two communities, Savelugu and Bukpomo, in northern Ghana to build the capacity of farmers on integrated pest management in cowpea production. The FFF involved a season-long comparative evaluation of farmers’ practices (FP) and integrated pest management (IPM). Farmers’ practices relied wholly on calendar insecticide sprays while IPM plots employed proven agronomic practices and treatment with neem (Azadirachta indica A. Juss) extract for insect pest control. Results showed that insect pest densities (Flower thrips, Megalurothrips sjostedti Trybom and pod-sucking bugs’ for example, Clavigralla tomentosicollis Stal.) and percent damaged pods as well as grain yield were similar in FP and IPM plots at both Savelugu and Bukpomo. Partial budget analysis showed positive returns to investment in IPM and a near loss in FP. Post training ballot box test showed that 80% of the farmer participants across locations showed improved knowledge and skills in IPM after the training compared with about 30% before the training. An ancillary study to the FFF was conducted to expose the farmers to different cowpea genotypes in a participatory variety selection trial. Results showed that some of the genotypes selected by farmers as their most preferred genotypes at the vegetative stage were also selected at the podding stage but there were no significant correlations between these farmer preferences and yield. These findings are discussed in the context of sustainable cowpea production through farmer empowerment and involvement in technology generation and dissemination. Key words: Farmer field fora, participatory variety selection, cowpea, Azadirachta indica.

MULTIPLE TACTICS OF INTEGRATED PEST MANAGEMENT FOR THRIPS ON STRAWBERRY PLANTATION

In management of thrips on strawberry, farmers usually use synthetic insecticides. Synthetic insecticide is not effective to control thrips and produce residual effect on crops. Insecticidal residue is dangerous for human, natural enemies and environment widely. Therefore, it is necessary to find an alternative thrips pest control on strawberries, through integrated pest manage-ment (IPM) implementation. Research was aimed to determine the effect of IPM technology for Thrips sp. on strawberry plantation. Research was conducted on strawberry plantation by comparing IPM and conventional plots, in Kusuma Agrowisata Batu from April to July 2009. Variables were used such as the number of larvae, adult population and damage intensity caused by Thrips sp., and fruit production. Data was analyzed by t-test on 5%. The results showed that the average larva and adult population of Thrips sp. on IPM plot were higher than conventional plot, 1.12 and 0.50 for larva and 0.87 and 0.27 for adults respectively. The damage intensity of strawberry crops on IPM plot was higher than conventional plot, 11.69 and 5.98% respectively. Based on average fruit production, IPM plot was higher than conventional plot, 48.32 g and 39.24 g respectively.

PENGARUH PERBEDAAN PENGELOLAAN AGROEKOSISTEM TANAMAN TERHADAP STRUKTUR KOMUNITAS SERANGGA PADA PERTANAMAN KEDELAI DI NGALE, KABUPATEN NGAWI, JAWA TIMUR

Effect of different agroecosystem management on community structure of insects in soybean crop in Ngale, Ngawi District, East Java. Insect community structures in agroecosystem may always change. Agroecosystem management techniques affect insect community structure. The aim of this study was to determine the diversity and composition of insects on soybean plants under different pest management systems and varieties. The experiment design was split plot with varieties (Anjasmoro and Wilis) as the main plots and pest management systems (Integrated Pest Management (IPM), Non-Chemical Management (P-NK), Chemical Management (P-K), and Control) as the sub plots. There were ten insect sampling sessions for each plot. Samplings were done in June until September 2013 using pitfall traps, sticky traps, sweep net, and yellow pan traps. Statistically the results of experiment showed that varieties and pest management had no significant differences to the insects diversity. Herbivore and beneficial insect in soybean crop had differences composition between varieties Anjasmoro and Wilis. In both soybean Anjasmoro and Wilis varieties, herbivore populations tend to be higher in the control plots compared to the IPM plots. Abundance of decomposers, parasitoids, and predators tend to be higher in the control and P-NK plots which were without the use of synthetic insecticides compared to the IPM and P-K plots which were given the treatment of synthetic pesticides. This indicates that the use of pesticides causes decrease in the beneficial insect populations such as pollinator, parasitoids, and predators.

An IPM Program for Managing Fungal Leaf Blight Diseases of Carrot in New York.

Fungal leaf blight diseases caused by Cercospora carotae and Alternaria dauci occur annually on processing carrot in New York, with growers applying up to eight fungicide sprays to manage these diseases. An integrated pest management (IPM) program involving the use of a 25% disease incidence threshold to prompt the first fungicide application and timing subsequent sprays by monitoring for increases in disease severity and weather forecasts in conjunction with a 10- to 14-day spray interval was evaluated in grower fields in 1997 and 1998. The IPM plots, compared with the grower plots, required two to six fewer fungicide applications but showed no yield reduction. From 1999 to 2004, the IPM program was validated and the effect of crop rotation and carrot cultivar susceptibility also were assessed. Carrot plants growing in fields with 2-year or longer crop rotation intervals reached the 25% disease incidence threshold later in the season and required fewer fungicide applications. The less-susceptible carrot cultivars also reached the 25% disease incidence threshold later, required fewer fungicide applications, and were less severely diseased than more susceptible cultivars. Validation of the IPM program in New York showed that both fungal leaf blights can be managed effectively using a 25% incidence threshold to prompt the first fungicide spray and making the subsequent fungicide applications based on increases in disease severity, weather forecasts, and a 10- to 14-day spray interval.

Development of mass trapping technique for control of brinjal shoot and fruit borer, Leucinodes orbonalis (Lepidoptera: Pyralidae)

Locally-produced clear plastic water traps (12 cm x 14 cm base and 21 cm height) were optimized for use in large-scale mass trapping trials for control of brinjal fruit and shoot borer, Leucinodes orbonalis Guenée. Changing the shape (square and triangular) and number (two and four) of entry holes in the water trap had no significant effect on trap catch. Significantly more male moths were caught in traps treated with water containing powdered detergent than liquid detergent, light gear oil or insecticide. All water traps tested caught significantly higher numbers of moths than sticky delta traps with open sides under farmers' field conditions. Trap catches per 100 m2 were found to increase with increasing number of traps from 3 to 6 but the difference in catch between 4 and 6 traps per 100 m2 was not significant. Two small-scale replicated integrated pest management (IPM) trials were conducted consisting of the optimized water trap placed out with 10 m spacing (4 per 100 m2) and infested shoots pruned and destroyed. The first season trial had two treatments, IPM and farmers' practice in which farmers applied insecticide every two days in the peak harvest period. Overall, the percentage of healthy fruit and yields in both treatments were comparable at 53.8 and 49.6% and 20 and 19.4 tonnes per ha in the IPM and farmers' practice plots respectively. However, the initial infestations in the IPM plots (68%) were significantly higher than in farmers' practice plots (16%) due to the proximity of the nurseries used for the IPM plots to stacks of brinjal crop residues from the previous season that acted as a source of infestation. The second season's trials contained a third treatment in which IPM and farmers' practice were combined. The percent total healthy fruits harvested were 46.1, 58.6 and 69.1% respectively for the farmers' practice, farmers' practice plus IPM and IPM alone. Averaged total fruit yields were approximately 12 tonnes per ha for the farmers' practice plots and 30 tonnes per ha for each of the IPM-treated plots. The IPM plot had significantly fewer infested fruit than the IPM plus farmers practice plots and this was attributed to the activity of the larval parasitoid Trathala flavo-orbitalis (Cameron) that was suppressed in trial plots treated with insecticides.

Evaluating a Wetness-based Warning System and Reduced-risk Fungicides to Manage Sooty Blotch and Flyspeck of Apple

The effectiveness of a disease-warning system and efficacy of reduced-risk fungicides for management of sooty blotch (Peltaster fructicola, Leptodontium elatius, Geastrumia polystigmatis) and flyspeck (Schizothyrium pomi) (SBFS) of apple (Malus × domestica) were evaluated in Illinois, Iowa, and Wisconsin in 2001 and 2002. Warning system-timed applications of the second-cover fungicide spray occurred when 175 h of leaf wetness had accumulated; wetness data were derived either from a sensor placed beneath the canopy of apple trees (on-site) or according to remotely sensed estimates. In replicated experiments, using sensor measurements as inputs to the warning system saved one to three (mean 1.8) and zero to four (mean 2.3) fungicide sprays per season in 2001 and 2002, respectively. Because remotely estimated wetness hours accumulated more rapidly than did on-site measurements, the warning system using remotely sensed wetness data saved only zero to one (mean 0.3) and zero to two (mean 0.7) sprays per season in 2001 and 2002, respectively. SBFS incidence in the integrated pest management (IPM) plots did not differ significantly from that of conventional calendar-based fungicide sprays plots in 11 of 12 site-years. When on-site wetness measurements were used in demonstration trials at 14 cooperating commercial orchards in 2001 and 2002, the SBFS warning system saved one to six (mean 2.6) and two to seven (mean 3.1) sprays per season, respectively. Incidence of SBFS in IPM plots did not differ significantly from trees managed with cooperating growers' conventional fungicide schedules in 16 of 28 siteyears. The on-site warning system was more consistently successful in Illinois and Iowa than it was in Wisconsin in both replicated experiments and in cooperating commercial orchards. The reduced-risk fungicides kresoximmethyl and trifloxystrobin provided control of SBFS equal to conventional fungicides (benomyl or thiophanatemethyl) in all trials. Potassium bicarbonate controlled SBFS less effectively than either conventional fungicides on a calendar-based or disease-warning schedule, or treatments incorporating reduced-risk fungicides.

Female sex pheromone of brinjal fruit and shoot borer, Leucinodes orbonalis (Lepidoptera: Pyralidae): trap optimization and application in IPM trials.

Delta and wing traps baited with synthetic female sex pheromone of Leucinodes orbonalis Guenée were found to catch and retain ten times more moths than either Spodoptera or uni-trap designs. Locally-produced water and funnel traps were as effective as delta traps, although 'windows' cut in the side panels of delta traps significantly increased trap catch from 0.4 to 2.3 moths per trap per night. Trap catch was found to be proportional to the radius of sticky disc traps in the range 5-20 cm radius, discs with a 2.5 cm radius caught no moths. Wing traps placed at crop height caught significantly more moths than traps placed 0.5 m above or below the crop canopy. Replicated integrated pest management (IPM) trials (3 x 0.5 ha per treatment) were conducted in farmers fields with young and mature eggplant crops. Farmers applied insecticides at least three times a week in all check and IPM plots. In addition pheromone traps were placed out at a density of 100 per ha and infested shoots removed weekly in the 0.5 ha IPM plots. Pheromone trap catches were reduced significantly from 2.0 to 0.4 moths per trap per night respectively in check and IPM plots in a young crop and 1.1 to 0.3 moths per trap per night in check and IPM plots respectively in a mature crop. Fruit damage was significantly reduced from an average of 41.8% and 51.2% in check plots of young and mature crops respectively to 22% and 26.4 respectively in the associated IPM plots. Significant differences in pheromone trap catches and fruit damage were attained four and two weeks respectively after IPM treatments began in the mature crop whereas in the immature crop significant differences were not observed for the first eight to nine weeks respectively. The relative impact of removing infested shoots and mass trapping on L. orbonalis larval populations was not established in these trials but in both cases there was an estimated increase of approximately 50% in marketable fruit obtained by the combination of control techniques compared to insecticide treatment alone.

The effect of integrated pest management practices in an apple orchard on Heteroptera community structure and population dynamics

Abstract: The community structure and population dynamics of Heteroptera was studied in an apple orchard in the Czech Republic, between 1992 and 1995. The study investigated the changes which occurred after introduction of integrated pest management (IPM) practices into an intensive apple orchard. The IPM consisted of establishing grass ground cover or planting six selected herb species in two wide belts along the rows of trees. The IPM areas were compared with areas where chemical control was continued. Seventy Heteroptera species were captured (22 predatory and 48 phytophagous). The diversity of heteropteran communities was always higher on IPM plots and six predatory species and 24 phytophagous species were only captured on the IPM plots. Annual variation of abundance of predatory species on IPM plots was smaller than in phytophagous species. Orius spp. were abundant on the chemical control areas due to abundant Tetranychus urticae C.L. Koch populations, which were probably a consequence of the application of pyrethroid insecticides. Other predatory species were more abundant in IPM areas due to higher prey availability. The abundance of phytophagous species was favoured by the herbaceous undergrowth of the IPM plots. The number of predatory Heteroptera species increased after the introduction of IPM practices. Vegetation cover diversity is enhanced due to cultivation of the plots with IPM regime and has not resulted in any additional increase in the abundance of predatory Heteroptera species.

Performance of a pyrethroid-resistant strain of the predator mite Typhlodromus pyri (Acari: Phytoseiidae) under different insecticide regimes.

An organophosphate pyrethroid-resistant strain of Typhlodromus pyri Scheuten imported from New Zealand was reared on potted apple trees in an outdoor insectary. From 1988 to 1995, the population was selected one to three times per year with a dilute solution (1.7 ppm) of the pyrethroid cypermethrin. Petri dish bioassays with cypermethrin in 1995 indicated that the insectary-reared T. pyri had an LC50 of 81 ppm versus 0.006 ppm for native T. pyri taken from a research orchard. The bioassays suggested that recommended orchard rates of cypermethrin would cause heavy mortality in native populations of T. pyri but only moderate losses in the imported New Zealand strain. Bioassays in 1996 with the organophosphate insecticide dimethoate indicated both New Zealand and native T. pyri were susceptible and that recommended orchard rates of dimethoate likely would cause high mortality of T. pyri in apple orchards. These findings from bioassays were supported by data from orchard trials. In June and July 1993, insectary-reared New Zealand T. pyri were placed on five apple trees in each of eight 38-tree plots in the research orchard. In late August 1994, New Zealand T. pyri from orchard trees that had been sprayed twice by airblast sprayer with the full recommended rate of 50 g (AI)/ha (83 ppm) cypermethrin were placed on the other 33 trees in each of six plots. In the summers of 1994-1996, plots were treated with one of the following insecticide regimes: (1) conventional integrated pest management (IPM) (registered neurotoxic insecticides considered harmless or slightly toxic to T. pyri); (2) advanced IPM (use of newer, more selective insecticides); (3) pyrethroid (at least one full-rate application of cypermethrin); (4) dimethoate; and (5) dimethoate plus pyrethroid. Densities of European red mite, Panonychus ulmi (Koch), were highest in all plots treated with dimethoate and in pyrethroid plots not yet inoculated with New Zealand T. pyri. Densities of apple rust mite, Aculus schlechtendali (Nalepa), and of the stigmaeid predator Zetzellia mali (Ewing) were highest in plots treated with dimethoate and were nearly absent in the IPM plots. Densities of T. pyri were high enough for effective biocontrol in the IPM plots and in the pyrethroid plots 1-2 yr after release of the New Zealand strain, provided pyrethroid was applied just before the resistant strain was released in the orchard. A recurring theme of this study was the generally negative association between densities of phytophagous mites and those of T. pyri, suggesting the ability of this predator to suppress their prey. In contrast, the positive association between phytophagous mites and Z. mali suggests the inability of this predator to regulate their prey at least under the conditions of this study.

Effect of IPM practices and conventional spraying on spider population dynamics in an apple orchard

Integrated pest management (IPM) is now practiced in commercial orchards in the Czech Republic. The effect of two IPM practices and conventional spraying on arboreal and understorey spider population dynamics was studied over four years. Conventional spraying included frequent applications of non-selective pesticides; IPM plots were treated with selective pesticides less frequently. IPM plots were undersown with various plantings or grass. The plot under conventional spraying, was grown by a naturally established weed stand. Conventional practice negatively influenced species diversity, particularly hunting spiders (Thomisidae and Philodromidae). A spraying programme applied on IPM plots reduced abundance of spiders less than the non-selective chemicals applied to the plot under conventional practice. Plantings on IPM plots increased overall species diversity, whereas undersowing of grass supported abundance of arboreal spiders. In general, IPM practice maintained the seasonal abundance of spiders at a balanced level, whereas conventional spraying caused violent fluctuations of late-summer spider populations. Late-summer abundances were determined by reproduction rather than aerial dispersal. Spring abundance of Theridion impressum was presumably influenced by winter predation by Philodromus cespitum.

Side‐effect of integrated pest management and conventional spraying on the composition of epigeic spiders and harvestmen in an apple orchard (Araneae, Opiliones)

The effect of two different integrated pest management (IPM) practices and conventional spraying (CHEM) on the composition of epigeic spiders and harvestmen in an apple orchard was investigated over 4 years. Conventional spraying included more frequent and nonselective pesticide applications, whilst IPM plots were treated with selective pesticides and less frequently. One of the IPM plots was undersown with various plantings, the other with grass, and the plot under conventional spraying was covered with weeds. In total, eight species of harvestmen and 65 species of spiders were recorded whose abundance peaked in spring and autumn. Arachnids were on average over the 4 years less abundant on both IPM plots than on CHEM which seems to be due to lower plant density of weed cover. Seasonal oscillations were only slightly different in particular seasons between plots, in particular during spraying. In 1992 the arachnids were a little more abundant on the conventional spraying plot, in 1993 on IPM plots and during subsequent 2 years the difference diminished. The seasonal abundance appeared to be influenced by herbicide applications. Species diversity of all plots were higher than in crop fields, but did not reveal disagreement between plots. The numerical hierarchical classification (TWINSPAN) detected that the composition of arachnids was influenced in particular by annual variation. The arachnid assemblages of the studied plots were not found to be markedly different during the whole study. The effect of IPM practices and conventional spraying on the composition of epigeic arachnids was far less apparent than it was in arboreal species. However, nearly 20% of spiders were found common with crown stratum. Some of them occupied both strata, a few occurred in epigeon only accidently, while others moved vertically during the season. Thus the epigeic fauna seems to support arboreal spiders.

Pesticide Effect on Faunal Composition, Abundance, and Body Length of Spiders (Araneae) in Apple Orchards

We studied differences in family and guild compositions, seasonal trends of abundance, and mean body length of spiders in Massachusetts commercial apple, Malus pumila (P. Mill), orchards under different pesticide regimes. The 4 guilds were active nocturnal hunters (Anyphaenidae), visual hunters (Oxyopidae and Salticidae), ambushers and runners (Thomisidae and Philodromidae), and web builders (mostly Araneidae and Theridiidae). In 11 orchard blocks in 1991 and 1992, we compared spider populations in 1st-level integrated pest management (IPM) plots (where insecticides were applied as needed through August) with those in 2nd-level IPM plots (where insecticides were applied only until early June). In a single orchard block in 1995, we compared spider populations in three 2nd-level IPM plots with those in plots that were not treated with pesticides. In all treatments, spider numbers increased over time. However, by the end of the growing season, spiders were 3 times more abundant in 1991 and 2 times more abundant in 1992 in 2nd-level than in 1st-level IPM plots. After treatment, the mean number of spiders collected in 2nd-level IPM plots in 1995 dropped to approximately 0, whereas it remained approximately the same in the unsprayed plots. Later in the season, spider numbers increased more rapidly in the unsprayed plots. We found no significant differences in family and guild compositions of spiders between 1st-level and 2nd-level IPM plots in 1992. In 1995, however, we found proportionately more philodromids and less theridiids in 2nd-level IPM plots than in the unsprayed plots. The mean body length of spiders did not differ between 1st-level and 2nd-level IPM plots in 1992. Following treatment, in 1995, mean body lengths of visual hunters and web builders were numerically smaller in 2nd-level IPM then in no pesticide plots. These differences were most probably caused by insecticide-caused mortality of resident adults in May in 2nd-level IPM plots. Because body lengths of spiders are related to the sizes and therefore the types of prey they consume, the negative effect of pesticides on mean body lengths of visual hunters and web builders may affect their role as predators of different types of arthropod pests. We conclude that insecticides, even if applied only early in the season, have a marked season-long negative effect on spider populations found on apple trees in commercial orchards in Massachusetts. This effect may differ depending on the spider species.

Development and economic evaluation of an IPM program for fresh market tomato production in Mexico

An integrated pest management (IPM) program based on intensive sampling, parasite releases, use of the mating disruption technique, and applications of microbial pesticides and abamectin was developed for the fresh market tomato industry in Sinaloa, Mexico. The IPM program for tomatoes was compared with conventional practices and an unmanaged control in each of three major agricultural valleys in autumn and winter crops, and in two valleys for spring plantings. The amount of marketable fruit production was similar for all treatments in the autumn plantings, but significantly higher in the IPM program during the winter and spring plantings. The densities of Liriomyza sativae Blanchard and Keiferia lycopersicella (Walsingham) eggs, larvae and adults were substantially reduced in the IPM treatment. Percent fruit damage by Spodoptera exigua (Hübner), Heliocoverpa zea (Boddie) and Heliothis virescens (Fabricius) was generally higher in the IPM treatment (4.2–10.9%) as compared with the conventional treatment (0.9–3.7%). However, the percent fruit damage by K. lycopersicella was significantly reduced in the IPM treatments (6.49–30.4%) vs. the conventional treatments (4.65–84.2%) in the winter and spring plantings. Net profits (value of fruit at harvest minus the cost of control) were substantially higher in the lower input IPM plots than in conventional treatments. In the autumn, net profits ranged from US$304 to US$579 ha −1 higher in the IPM treatment for carton values of US$5–US$11, respectively. In the winter and spring plantings, only the IPM approach was profitable. The IPM program offers substantial, long-term benefits in comparison with the conventional approach. Not only was the cost of the IPM program considerably less, but it: (1) reduced the potential for pesticide resistance development; (2) reduced the possibility of potential mammalian toxicity or non-target effects by using less toxic pesticides that are specific in activity; (3) provided less chance for fruit contamination or environmental damage.