共查询到20条相似文献，搜索用时 93 毫秒
1.
According to the new trend of insect pests control in fruit orchards, biological in addition to mechanical control were evaluated
for their efficiency on the reduction ofP. paradoxa population on fig trees during 1996, 1997 and 1998. Primary trials using the bacterial biopreparations of Delfin, Dipel and
Bactospeine at the concentration of 200g/100 l. w. resulted in 81.8, 75.8 and 72.3% reduction of pest infestation, respectively.
Pruning the infested branches, worming the larvae inside their tunnels and both mechanical treatments together along two successive
years, reduced the infestation by 17.5, 47.4 and 57.9%, respectively. A control programme ofP. paradoxa was conducted using the techniques of pruning and worming besides spraying with bacterial insecticides at a rate of 200g/100
l.w. The performed mechanical and biological treatments together for one year gave 79.2–94.5% reduction of infestation, that
reduction increased to 83.0–98.1% when these treatments were applied two years successively. 相似文献
2.
Field experiments were conducted using the biological agentBacillus thuringiensis to control the clearwing moth,Synanthedon myopaeformis (Lep. Aegeriidae) in apple orchards at Alexandria governorate during 1995, 1996 and 1997. Three bacterial varieties ofB. thuringiensis showed significant influence on the reduction of borer infestation. Four applications with the sporic concentration 12×107 spores/ml of each ofB. th. var.kurstaki, B. th. var.alesti andB. th. var.thuringiensis induced 82.5, 51.1 and 42.1% reduction of infestation, respectively. Methods of application showed highly significant effect
on infestation level. Sparying after scraping was the best method (80.0%, reduction) followed by painting after scraping (71.5%,
reduction) then spraying alone (59.7%, reduction) or painting alone (43.0%, reduction). A control programme was carried out
using three applications of the biomaterial, Delfin at the rate of 200 g/100 I.w. during mid-March, early June and mid-August
resulted in 88.5–91.4% reduction of infestation. 相似文献
3.
The efficacy of two commercial products of Bactospeine and Bio-fly onPrays citri of lime trees was studied under laboratory and field conditions throughout the two seasons of 1996 and 1997. Laboratory results
indicated that the pathogenic effect of Bactospeine,Bacillus thuringiensis (Berliner) was higher than that of Bio-fly,Beauveria bassiana in spite of the latter was applied with higher doses. Bactospeine at the rate (2 cc/1 l.w.) effected on the larvae more than
on the adults, that treatment reduced no. of eggs/female by 81.70% and decreased the larval infestation by 90.08%. Bio-fly
at the highest concentration (4 cc/1 l.w.) reduced the infestation with the eggs, the larvae and the pupae by 65.83%, 68.45%
and 72.55%, respectively. Advanced effects of bacterial and fungal treatments on the final reduction rates ofP. citri infestation were recorded. Field applications revealed that two sprays with Bactospeine or Bio-fly gave good control ofP. citri more than one spray. Bactospeine at the rate (2 cc/1 l.w.) and Biofly at the rate (4 cc/1 l.w.) reduced the infestation by
(89.82–93.43%) and (76.32–78.83%), respectively. In all cases, higher doses of bioinsecticides produced potentiation effects
of infestation reduction. It is recommended that two sprays of Bactospeine at a rate (2cc/1 l.w.) are adequate effective to
reduce the population of P. citri in lime orchards during the main flowering period of trees without need of chemical insecticides.
An erratum to this article is available at . 相似文献
4.
Diafenthiuron (CGA 106 ’630), a thiourea, was sprayed prior to a 48-h infestation by adult females of the sweetpotato whiteflyBemisia tabaci Gennadius, on cotton seedlings under greenhouse conditions; it subsequently suppressed strongly progeny formation of the
whitefly, resulting in approximately 50% progeny formation relative to control at 5 mg a.i./l. When the different development
stages were separately sprayed directly, the larval stage was the most susceptible, resulting in 50% and 90% mortality of
2nd instars at concentrations of 6.5 and 49.2 mg a.i./l, whereas the LC50 values of adults and pupae were 23 and 45 mg a.i./l,
respectively. A mild (30–35%) reduction of egg hatch was obtained at a range of 5–125 mg a.i./l. Thus the potency of diafenthiuron
against various stages was in the order larvae > adults > pupae > eggs. Diafenthiuron exhibited a low vapor phase toxicity
and had no translaminar effect when tested on first instars ofB. tabaci. The high potency of diafenthiuron against whiteflies described herein, against aphids and mites, as stated in the literature,
and against some lepidopterous pests, render this compound an important insect control agent for pests of cotton and other
crops. 相似文献
5.
The calculated percentage of droplets deposition ofBacillus thuringiensis var.kurstaki HD-1 Dipel 2X on the foliage of soybean plants in relation to the sensitive “Ciba Geigy” papers showed to be the highest
(92.4%) after ground spray application, compared to an average of 67.4, 85.8 and 89.3% following aerial application of the
same preparation in spray volumes of 10, 20 and 30 l/F, respectively.
Aerial application ofB. t. showed to be more effective during the first 3 days after spraying soybean cultivations and the mortality ofSpodoptera littoralis larvae varied between 36.9–67.2% in correlation to the spray volume. The volume achieving the highest and significant suppression
of infestation was 20 l/F. On the other hand, the yield of soybeans obtained from plots receiving a spray volume of 30 l/F
was higher compared to plots sprayed with a volume of 20 or 10 l/F, but with no significant difference when compared to those
plots receiving ground spray application. 相似文献
6.
Dry mycelium (DM) of killedPenicillium chrysogenum and its water extract (DME) were used to induce resistance in cotton plants againstFusarium oxysporum f.sp.vasinfectum (Fov). Results showed that the efficacy of either DM or DME in controlling the disease depends on both the concentration and the
mode of application. DM amended to the soil at 0.25–2% (w/w) provided 32–75% protection againstFov. Soil drench with 2–5% DME (w/v) and pre-sowing seed soakage with 5–10% DME provided 51–77% and 28–35% protection against
the wilt disease, respectively, whereas no protection was obtained with foliar sprays of 1–10% DME. DM and its water extract
had no direct antifungal activity on growth ofFov in vitro, suggesting that disease control with DM or DME resulted from the induction of natural defense mechanisms in the cotton plants.
Soil drench with 5% DME was as effective as 2% DM powder in inducing resistance againstFov, implying that the resistance-inducing substances were mostly water-soluble. Four cotton cultivars with various genetic resistance
levels againstFov were tested at the seedling stage: two resistant ‘Pima’ cultivars and two susceptible ‘Acala’ cultivars. The level of protection
achieved in the two susceptible cultivars with DME was equal to, or higher than, that of the two resistant cultivars treated
with water. Innate and induced peroxidase activity in cotyledons or hypocotyls and roots coincided with the level of genetic
resistance and DME-induced resistance, respectively. Based on our results, an integrated control strategy ofFov with both genetic resistance and induced resistance is suggested. 相似文献
7.
A study was conducted to determine the feasibility of using sclerotia ofSclerotinia sclerotiorum for producing conidia ofConiothyrium minitans in liquid culture. The medium (SST) was made of water containing 2.0, 1.5, 1.0 or 0.5% (w/v) ground sclerotia ofS. sclerotiorum and 100 μgl
−1 thiamine hydrochloride (HCl). One ml of conidial suspension (2 × 107 conidia ml−1) ofC. minitans LRC 2534 was inoculated into 100 ml of SST medium or control (thiamine HCl in water) and incubated at 20 ± 2°C on a shaker
at 200 rpm. Subsamples were removed periodically and examined under a compound microscope. Conidia in the SST media germinated
within 24 h, developed into branched hyphae within 48 h, produced pycnidia after 3–4 days, and the pycnidia released mature
conidia after 7 days. Production of conidia varied with the concentration of sclerotia in the SST medium. It was lower (3.6
× 106 conidia ml−1) at 0.5% but higher (1.2 × 108 conidia ml−1) at 2%. The new conidia were viable and the colonies developing from them showed the original morphological characteristics.
It was concluded that using SST liquid medium as a substrate for mass production of conidia ofC. minitans has potential for use in commercial development of this mycoparasite as a biocontrol product.
http:www.phytoparasitica.org posting Jan. 23, 2007. 相似文献
8.
Abstract Two field experiments were conducted in Cairo to determine if outdoor u.l.v. bioresmethrin would control a heavy housefly infestation. In the first trial, a 100 ha site surrounding a slaughterhouse was treated on five successive mornings with 10 g/ha of bioresmethrin in 470 ml of diesel oil. The mean daily outdoor reduction in the adult fly population, principally Musca domestica vicina Macquart, at 0900 h following application of the u.l.v. aerosol was 96%. In the second trial, the same procedure was adhered to and the site was treated on 14 successive mornings at the same dosage level using the same equipment in order to interrupt the life cycle. A mean daily density reduction of about 99% was obtained. This represents a reduction from 1,147 flies per grill count to only three. After the last consecutive treatment the fly population failed to rise appreciably and subsequently, two further treatments were carried out at weekly interva's. 相似文献
9.
Ten microorganisms of the epiphytic microflora of wheat leaves in Buenos Aires Province, Argentina, were evaluated under greenhouse
conditions as potential biocontrol agents of the pathogensAlternaria triticimaculans, Bipolaris sorokiniana, Drechslera tritici-repentis andSeptoria tritici in two application sequences (prior to or together with the pathogens). The antagonists significantly reduced the expression
of the diseases on wheat plants compared with control plants not inoculated with the antagonists. Maximum percentage of reduction
of the necrotic lesion area (NLA) (40–55%) ofS. tritici resulted whenCryptococcus sp.,Rhodotorula rubra andPenicillium lilacinwn were sprayed on leaves prior to inoculations with the pathogen.Bacillus sp.,Cryptococcus sp.,Fusarium moniliforme var.anthophylium,P. lilacinum andR. rubra reduced significantly (34–52%) the NLA ofB. sorokiniana in both of the application sequences. The best antagonistic effect againstA. triticimaculans was shown byAspergillus niger, Bacillus sp.,Chaetomium globosum, F. moniliforme var.anthophylium andNigrospora sphaerica, with a NLA reduction from 21% to 35% in the co-inoculation or in the sequential application. All microorganisms exceptN. sphaerica performed better than the control againstD. tritici-repentis. The area under disease progress curve (AUDPC) of the pathogens appeared to progress similarly, but at lower values, in treated
plants than in untreated controls. The two yeasts and the bacteria decreased AUDPC to 50–55% ofS. tritici andB. sorokiniana compared with the control in both application sequences, whereas the maximum efficacy againstA. triticimaculans was reached byN. sphaerica andA. niger for the sequential application and byF. moniliforme var.anthophylium for the co-inoculation. If the parasitism occurs also in nature, application of antagonists for biological control might
provide the opportunity to compete with the pathogens and regulate their colonization in wheat leaves. 相似文献
10.
The influence of different light regimes on the germination of Australian and English populations of Phalaris paradoxa L. (awned canary‐grass) seed was investigated to determine the impact of changing tillage practices on weed infestation. Seeds of all biotypes were highly viable, but differed in levels of innate dormancy (26–99%). In one experiment seed from a single Australian biotype, either enclosed in the spikelet glumes or having the spikelet glumes removed, were exposed to nine light treatments. Germination was stimulated by red and white light, but was inhibited by far‐red light. Time to 50% germination was less for seed enclosed in the spikelet glumes than for naked caryopses, although the final percentage of seed germinating when still enclosed in the spikelet glumes was significantly lower than for naked caryopses. In another experiment, six Australian and English biotypes with varying dormancy characteristics were exposed to eight light treatments. Red light did not stimulate germination in the deeply dormant biotype, however stimulated all other biotypes. Germination in darkness was below 20% in all biotypes except for one where germination was 51%. To overcome dormancy seeds were imbibed and placed in darkness at 16°C for either 7 or 14 days prior to exposure to red or white light for a single 15‐min period. Dormancy in all biotypes was overcome indicating that a period of burial may decrease the dormancy level and increase seed sensitivity to light. This increased light sensitivity suggests that exposure to light during tillage may stimulate germination in P. paradoxa seed. 相似文献
11.
Among 153 isolates ofRhizoctonia spp. obtained from 95 soil samples collected from different fields in the USA, 42 (27.5%) isolates were hypovirulent or non-pathogenic
on cabbage (tested on tap water agar plus 250 μg/ml chloramphenicol plates). Of these, 14 (33.3% of the np-R) isolates protected
>60% of the cabbage seedlings againstR. solani, and the best eight isolates protected 73–95% of the cucumber seedlings. The np-R isolates RU56-8 (AG-P) and RU89-1 [AG-B(o)]
induced the highest resistance against hypocotyl challenge inoculation with virulentR. solani (38.3–85.7%), whereas most of the challenged control seedlings (85–100%) collapsed. Similarly, isolates RU56-8 and RU89-1
induced the highest resistance (22.2–87.5%) against hypocotyl challenge inoculation withPythium aphanidermatum, whereas most of the challenged control seedlings collapsed (90–100%). Isolates RU56-8 and RU89-1 significantly reduced the
lesion numbers and area/leaf (to 8.9–42.0% of the control) caused by challenge inoculation of the first true leaves withPseudomonas syringae pv.lachrymans. No np-R isolate could be recovered from the upper hypocotyls or from the leaves, indicating that there was no contact between
the inducer and the pathogen. Root colonization with some np-R increased seedling tolerance to low soil moisture levels. 相似文献
12.
Imre J. Holb 《European journal of plant pathology / European Foundation for Plant Pathology》2006,115(3):293-307
A two-year study was conducted to determine the effect of six sanitation treatments on leaf litter density (LLD), relative ascospore production of Venturia inaequalis and scab incidence on spur-leaf clusters, leaves and harvested fruits, on two cultivars with low and high scab susceptibilities, in Hungarian integrated and organic apple orchards. The following sanitation treatments were used: sprays of lime sulphur in autumn, collecting fallen leaves in autumn, straw mulch cover in late winter, sprays of lime sulphur followed by mulch cover, collecting fallen leaves followed by mulch cover, collecting fallen leaves followed by covering the orchard floor with plastic foil, and non-sanitized control. LLD decreased continuously in all treatment plots by 0–23% by mid-May in both orchards and years; however, LLD reduction was 1.4–4.2 times higher in the organic orchard compared to the integrated one. All treatments, except for the lime sulphur treatment, resulted in significant (P < 0.05) reduction of LLD and ascospore production in both the integrated and organic apple orchards compared to non-sanitized plots. The most efficient treatment was leaf collection combined with plastic foil cover, followed by leaf collection combined with mulch cover, leaf collection alone, mulch cover alone, and lime sulphur spray combined with mulch cover, with a reduction in the ascospore production of >95, 72–92, 56–79, 24–38, and 27–46%, respectively, in the mean of both orchards and years. However, only treatments of leaf collection applied alone, or in combination with mulch or with plastic foil cover reduced significantly (P < 0.05) leaf and/or fruit scab incidence by 18–57% compared to non-sanitized plots. These three leaf collection treatments are recommended in both integrated and organic orchards and the possibilities of successfully incorporating these methods into orchard management practices are interpreted. 相似文献
13.
The potential of entomopathogenic nematodes for biological control of the European corn borer (ECB),Ostrinia nubilalis (Hübner), was evaluated under laboratory, screenhouse and field conditions. The ‘All’ and ‘Mexican’ strains ofSteinernema carpocapsae (Weiser) and the ‘HP88’ strain ofHeterorhabditis bacteriophora Poinar were compared in both dose response assays (5, 50 and 500 infective juveniles [IJ] per petri dish containing five
5th-instar ECB eggs; 72 h of incubation) and exposure time assays (3, 6 and 9 h of incubation). In the dose response assays
the highest rates of ECB killing resulted from infestation with the Mexican strain ofS. carpocapsae. In the exposure time assays there were no significant differences between the killing rates of the three nematode strains.
Sweet corn plants(Zea mays var.saccharata) grown in a screenhouse, were infested with ECB neonates and 4 days later sprayed with a suspension of the Mexican strain
ofS. carpocapsae (50,000 IJ per plant). The number of ECB larvae found on treated corn plants after one week was significantly (P=0.05) lower
(3- to 5-fold) than the number found on untreated plants. Similar treatment in the field significantly reduced the rate of
economic ear damage from 20% to 5%.
Contribution from the Agricultural Research Organization. No. 2260-E, 1997 series 相似文献
14.
The efficacy of a seed treatment of oilseed rape (OSR) (Brassica napus) with the rhizobacteria Serratia plymuthica (strain HRO-C48) and Pseudomonas chlororaphis (strain MA 342) applied alone or in combination against the blackleg disease caused by Leptosphaeria maculans was tested with different cultivars. Seeds were soaked in bacterial suspensions (bio-priming) to obtain log10 6–7 CFU seed−1. Cotyledons were inoculated with a 10 ul droplet of L. maculans spore suspension of log10 7 spores ml−1 and the disease index (size of lesions) was evaluated 14 days later. A mean disease reduction of 71.6% was recorded for S. plymuthica and of 54% for P. chlororaphis. The combined treatment was not superior to the treatment with S. plymuthica alone. The reduction of the disease caused by S. plymuthica was independent of the cultivar’s susceptibility, whereas the control effect recorded with P. chlororaphis increased with decreasing cultivar resistance to blackleg disease. The bacterial colonization of OSR was restricted to the
roots and hypocotyl. No significant difference in bacterial colonization of the rhizosphere was observed between different
cultivars, nor between single or combined bacterial seed treatments. 相似文献
15.
Better soil disinfestation methods, such as biological soil disinfestation (BSD), that are environmentally safe are increasingly
been developed and used because of rising concerns related to environmental risks. We evaluated the efficacy of soil disinfestation
using ethanol to control the fungus Fusarium
oxysporum f. sp. lycopersici, which causes fusarium wilt of tomato. Survival of bud cells and chlamydospores declined markedly in soil saturated with
diluted ethanol solution in the laboratory. In field trials, artificially added nonpathogenic Fusarium
oxysporum and indigenous F. oxysporum were both strongly suppressed in soil saturated with 1% ethanol solution; a wheat bran treatment was not as effective. The
artificially added fungus was not detected in three of four sites treated with ethanol but was detected in three of four sites
amended with wheat bran. Using ethanol in pre-autoclaved soil was not suppressive; thus native microorganisms are essential
for the suppression. This ethanol-mediated biological soil disinfestation (Et-BSD) temporarily increased the number of anaerobic
bacteria, but the number of fungi and aerobic bacteria was stable. Polymerase chain reaction–denaturing gradient gel electrophoresis
(PCR–DGGE) analysis revealed slight but apparent differences in bacterial community structures in the soil treated with Et-BSD
compared with the structure in soils after other treatments such as water irrigation and in the control soil, which received
neither organic amendment nor irrigation after 15 days. Et-BSD is a potentially effective and easy soil disinfestation method,
and its impact on native, beneficial microorganisms is moderate. 相似文献
16.
Joseli da Silva Tatagiba Luiz Antonio Maffia Roberto W. Barreto Acelino C. Alfenas John C. Sutton 《Phytoparasitica》1998,26(1):8-19
Microbial isolates from living petals, petal residues and leaf residues of rose, and from laboratory collections, were evaluated
for control ofBotrytis cinerea in rose. In leaf residues artificially infested withB. cinerea, isolates of the filamentous fungiGliocladium roseum, FR136 (unidentified) andTrichoderma inhamatum reduced sporulation of the pathogen by >90%, other filamentous fungi were 25–90% effective, and those of yeasts and bacteria
were <50% effective. In artificially inoculated petal residues, no microbe reduced sporulation ofB. cinerea by >75%, but isolates ofCladosporium oxysporum and four yeasts were 51–75% effective, and three filamentous fungi, eight yeasts andBacillus subtilis isolates were 26–50% effective. Isolates ofT. inhamatum, C. oxysporum andG. roseum performed best againstB. cinerea among isolates evaluated in leaf residues naturally infested with the pathogen and indigenous microorganisms. Totals of ten
isolates of filamentous fungi (includingC. oxysporum andC. cladosporioides), two of yeasts and five ofBacillus subtilis completely prevented lesion production byB. cinerea in detached petals, and a further six isolates of filamentous fungi (includingG. roseum) and six yeasts were 90–99% effective. Isolates ofC. oxysporum, C. cladosporioides andB. subtilis, the most effective microorganisms againstB. cinerea in flower buds, reduced number of lesions in the range of 42–65% compared with 59–89% for à standard fungicide (vinclozolin).
It is suggested that application of leading antagonists Jo living rose leaves and flowers should optimize control of inoculum
production byB. cinerea when the tissues die. Optimal biocontrol of lesion production in flower buds requires a better understanding of the microenvironment
of petals. 相似文献
17.
In a study of date fruit damage caused byOligonychus spp., we investigated whether the cultivar affects phenology, and on what hosts the mites over-winter. Samples were taken
from ‘Deglet Noor’, ‘Barhi’ and ‘Medjool’ trees from mid-April through mid-September during the years 1999–2002. In the ground-cover
mites were monitored by collecting Bermuda grass (Cynodon dactylon) under each sampling tree. Over 99% of the mites collected on Deglet Noor and Barhi fruit were identified asO. afrasiaticus. Mean population levels ofO. afrasiaticus reached ten mites or more (initiation of infestation) on Medjool in the second half of May, whereas on Deglet Noor this did
not occur before the first week of July. On Barhi the initiation of infestation varied between plots and years, ranging from
the second half of May to the beginning of July, but always occurred earlier than Deglet Noor. Mite populations on the pinnae
remained low from June through October, not exceeding seven mites per pinna, whereas on fruit strands they reached peak populations
of approximately 4000 mites per strand. The sex ratio (proportion of females) ofO. afrasiaticus on fruit of all three cultivars was highly female-biased, usually above 0.85. During winter,O. afrasiaticus was found on Bermuda grass in the orchard ground-cover as well as on fronds of all three cultivars.
http://www.phytoparasitica.org posting Jan. 30, 2003. 相似文献
18.
In a 2-year field study, the effects of four heating regimes established by varying temperature or duration of heating on
efficiency of on-farm wastes as soil amendments in controlling Fusarium oxysporum f.sp. cumini (Foc) causing wilt on cumin (Cuminum cyminum L.), were ascertained. Significant improvement in reduction of Foc propagules was achieved with the increase in duration and amount of heat. In 2000, mild heating under shade (heat level 4),
31.8–65.9% reduction in Foc propagules was estimated in all the amendments at 0–30 cm soil depth, which improved by 75.7–86.5% in the treatment where
Foc-infested soil brought from the laboratory was exposed to direct heat (heat level 3) and amendments and irrigation were applied.
Foc propagules were reduced by 76.6–88.3% when infested soil was exposed continuously to dry heat for 56 days (heat level 2),
improving efficiency of amendments by 0.9–13.5% compared with heat level 3. After 56 days of exposure to dry heat, elevating
the temperature by mulching amended soil with a transparent polyethylene film (50 μm thick) for 20 days (heat level 1) augmented
reduction by 80.2–95.5%. In the second season, combining 0.04% of onion, Verbisina encelioides or mustard oil-cake with mustard residues (0.18%) improved the reduction in Foc propagules at all heat levels even at the lower soil depth. Maximum reduction (94.9–100%) in Foc propagules at heat levels 1 to 3 was achieved when residues of Verbisina were supplemented with those of mustard. These results suggest a new approach to improve the control of Foc by combining prolonged heating with on-farm wastes such as Verbisina residues and one summer irrigation. 相似文献
19.
The pine processionary caterpillar,Thaumetopoea pityocampa is the most important defoliator of both native and introduced pines throughout Italy and is especially damaging in young
plantations and on ornamental trees. A number of microbial pathogens have been isolated from larvae and pupae over the last
30 years. Some of them have been evaluated as biological control agents, and have provided encouraging results. However, onlyBacillus thuringiensis var.kurstaki (Btk) has passed the experimental screening and is now available for routine treatments, although its application by air is subjected
to strict regulation by the government. The erratic performance of a single application ofBtk againstT. pityocampa that has been observed in the field (20–85% mortality) is related to a great variability in both the application dose and
some population parameters ofT. pityocampa. The emergence period of adults varies from July (Alps) to October (South) and its duration is related to the spreading of
the cohorts (individuals with different length of prolonged diapause) over time. In addition, embryonic development takes
from 20 to 45 days, depending strictly on the temperatures recorded in the egg masses. As a result, the most vulnerable larval
instars (L1 and L2) are never thoroughly reached by one application only, as the persistence of the bacteria on the needles
is usually limited. Two applications are requested to control the pest in stands where the egg hatching occurs over more than
one month. Another possibility consists of a single winter application against L3−L4 with a higher dose, to be performed where
a certain amount of damage is tolerated. 相似文献
20.
Systemic injection of neem (azadirachtin) was tested in the control of horse chestnut leafminer,Cameraria ohridella Deschka & Dimic (Lepidoptera: Gracillariidae), a pest of horse chestnut trees (Aesculus hippocastanum L.: Hippocastanaceae). Three concentrations, 0.08, 0.15 and 0.25 g of active ingredient (a.i.) per cm of diameter at breast
height (dbh), provided long-lasting insecticidal activity. The 0.15 and 0.25 g a.i. concentrations resulted in 100% pupae
reduction in all generations; the 0.08 g a.i. concentration was effective against the horse chestnut leafminer for at least
23 weeks and led to 70–80% pupae reduction. Treated trees did not lose their leaves before winter. Neem applicationvia injection is cheap, with no environmental hazards, and thus this treatment is recommended for the control ofC. ohridella in horse chestnut trees.
http://www.phytoparasitica.org posting Dec. 19, 2004. 相似文献