Managing apple scab (Venturia inaequalis) and powdery mildew (Podosphaera leucotricha) using Adem™

Current control of scab and mildew of apple in the UK requires the routine application of fungicides at 7 - 14-day intervals to achieve the blemish-free fruit required by the market. Such practices are generally effective, but with increased public concern about pesticides and rising costs to the grower, they are now less acceptable. The use of disease-warning systems offers scope for optimizing fungicide use by better timing of sprays. Adem^? is a PC-based system that warns of the risk of scab, mildew, Nectria fruit rot and canker and fireblight. In a 'key stage' strategy, warnings by Adem^? for scab and mildew integrated with practical pest and disease control resulted in similar or better control than a routine programme, with the additional benefit of reduced fungicide inputs and costs even in seasons exceptionally favourable for these diseases. Maximum savings in fungicide use were made by applying sprays curatively in response to scab warnings. However, this approach resulted in increased disease incidence to the crop and scab infection of fruit even in seasons unfavourable for scab attack.     

Effects of herbicides on rice resistance and on multiplication and feeding of brown planthopper (BPH), Nilaparvata lugens (StÅl) (Homoptera: Delphacidae)

Two-way effects of herbicide on rice resistance and multiplication and feeding of the rice brown planthopper (BPH), Nilaparvata lugens (Stål) were studied. Four of 11 herbicides tested, butachlor, metolachlor, oxadiazon and bentazone, had significantly stimulating effects on multiplication and feeding of BPH. Multiplication times (N ₁/N ₀) of BPH on the rice treated with the four herbicides were 674, 367, 322 and 311, respectively, while that of N. lugens on the untreated plants was 159. The results of measurements of honeydew production by BPH indicated that the feeding rates of the brown planthoppers increased when the insects fed on the plants treated with bentazone, quinclorac, oxadiazon and quinclorac. Survival rates of N. lugens first to third-instars rose on the rice plants treated with butachlor, bentazone, but that of the fourth and fifth instars were not affected. Furthermore, all of those herbicides tested led to a decline of rice resistance, i.e. the injury scales of the treated plants were larger than that of the control under the same pest stress. Based on their effects on rice resistance and on BPH, the herbicides tested can be divided into two categories, one affecting rice resistance and BPH multiplication, the other affecting rice resistance only.     

Effectiveness of two insect growth regulators against Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) and Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) and their impact on population densities of arthropod predators in cotton in Pakistan

Field efficacies of two insect growth regulators (IGRs) at two recommended application rates, buprofezin at 370 and 555 g AI ha(-1) and lufenuron at 37 and 49 g AI ha(-1), were determined against the sweet potato whitefly, Bemisia tabaci (Gennadius), and the cotton bollworm, Helicoverpa armigera (Hübner), in experimental plots of cotton at the Directorate of Cotton Research, Faisalabad, Pakistan. Adverse effects of the IGRs on populations of associated arthropod predators, namely geocorids, chrysopids, coccinellids, formicids and arachnids, were also assessed. Both IGRs significantly reduced populations of B. tabaci at each application rate 24, 48 and 72 h after treatment, and higher doses were more effective than lower doses. Buprofezin was not effective against H. armigera at any tested dose for any time of treatment in any spray. Lufenuron applied at 37 and 49 g AI ha(-1) effectively suppressed H. armigera populations, resulting in significant reductions in crop damage. At lower doses, both IGRs appeared safe to predator populations, which did not differ significantly in IGR-treated versus untreated control plots. Population densities of formicids and coccinellids were significantly lower at high concentrations of both IGRs in treatment plots, possibly as a result of reduced prey availability. The potential role of buprofezin and lufenuron for control of B. tabaci and H. armigera in a spray programme and the likelihood of direct toxic effects of IGRs on predatory fauna of cotton are discussed.     

Survey of two artichoke moths “Gortyna xanthenes (Germar) and Depressaria erinaceella (Staudinger)” in Tunisia

Journal of Plant Diseases and Protection - Gortyna xanthenes (Germar) and Depressaria erinaceella (Staudinger) are key pests of artichoke in Tunisia causing major losses. To this end, a 2-year...     

Phytogard® and DL-β-amino Butyric Acid (BABA) Induce Resistance to Downy Mildew (Bremia Lactucae) in Lettuce (Lactuca sativa L)

Downy mildew of lettuce (Bremia lactucae) is a serious disease. An alternative to chemicals is the application of disease resistance inducers. The aim of this study was to test whether DL--amino butyric acid (BABA) and Phytogard® (K₂HPO₃) could induce resistance in downy mildew susceptible plants. Aqueous solutions of BABA (0, 10, 20, 30, 50, 80, 100mM) and Phytogard® (0.0, 5.8, 29.0, 40.6, 58.0 and 87.0ppm) were sprayed on seven-day-old seedlings 0, 3, 7 and 15 days before or 1–3 days after inoculation with B. lactucae. Results obtained showed that Phytogard®- and BABA-induced resistance was dose-dependent. At 40.6ppm for Phytogard® and 10mM for BABA, complete protection was obtained. Both compounds had a curative effect and the induced resistance lasted for at least 15 days. It was also shown that both compounds induced systemic resistance in lettuce against downy mildew. Phytogard® at 40.6ppm completely inhibited spore germination while BABA at 20mM did not. Pathogenesis related (PR) protein analysis showed that BABA induced weak accumulation of PR-2, but not PR-1, PR-5 and PR-9. Phytogard® induced none of these proteins. The use of these two compounds to protect lettuce from B. lactucae is discussed.     

Important invasive species and its pest status in Turkey: Halyomorpha halys (Stål) (Heteroptera: Pentatomidae)

Journal of Plant Diseases and Protection - The brown marmorated stink bug, Halyomorpha halys (Stål), is a pest of many annual and perennial agricultural products. The species is native to...     

Deoxynivalenol, Nivalenol and Moniliformin in Wheat Samples with Head Blight (scab) Symptoms in Poland (1998–2000)

Fusarium head blight (scab) epidemics of wheat occurred in uawy (Northern Poland) during 1998 and in Wielkopolska (West) and in Southern regions of Poland in 1999. Four species were identified in wheat heads with scab symptoms: Fusarium culmorum, Fusarium graminearum, Fusarium avenaceum and Microdochium nivale. A significant increase in the frequency of F. graminearum (between 23% and 38%), was observed, compared to about 10% during the previous decade. The mycotoxins deoxynivalenol (DON), nivalenol (NIV) and moniliformin (MON) in amounts up to 24.3, 14.2 and 1.72mgkg^–1respectively, were identified in kernels samples.     

Identification and expression profiles of nine glutathione S-transferase genes from the important rice phloem sap-sucker and virus vector Laodelphax striatellus (Fallén) (Hemiptera: Delphacidae)

BACKGROUND: Glutathione S‐transferases (GSTs) have received considerable attention in insects for their roles in insecticide resistance. Laodelphax striatellus (Fallén) is a serious rice pest. L. striatellus outbreaks occur frequently throughout eastern Asia. A key problem in controlling this pest is its rapid adaptation to numerous insecticides. In this research, nine cDNAs encoding GSTs in L. striatellus were cloned and characterised. RESULTS: The cloned GSTs of L. striatellus belonged to six cytosolic classes and a microsomal subgroup. Exposure to sublethal concentrations of each of the six insecticides, DDT, chlorpyrifos, fipronil, imidacloprid, buprofezin and beta‐cypermethrin, quickly induced (6 h) up‐expression of LsGSTe1. The expression of LsGSTs2 was increased by chlorpyrifos, fipronil and beta‐cypermethrin. Furthermore, exposure of L. striatellus to fipronil, imidacloprid, buprofezin and beta‐cypermethrin increased the expression of the LsGSTm gene after 24 or 48 h. CONCLUSION: This work is the first identification of GST genes from different GST groups in Auchenorrhyncha species and their induction characteristics with insecticide types and time. The elevated expression of GST genes induced by insecticides might be related to the enhanced tolerance of this insect to insecticides and xenobiotics. Copyright © 2012 Society of Chemical Industry     

Correction to: Survey of two artichoke moths “Gortyna xanthenes (Germar) and Depressaria erinaceella (Staudinger)” in Tunisia

Journal of Plant Diseases and Protection - The names of the varieties cultivated in the two study regions were given wrongly in the Materials and Methods section. The correct names are as follows.     

Characterization of α-amylase and its activity from mustard aphid Lipaphis erysimi (Kalt.) (Hemiptera) and its inhibition by Rorippa indica defensin

Abstract

Lipaphis erysimi Kaltenbach is one of the economically important pests of Indian mustard Brassica juncea. Plant defense against these pests include impairing digestive processes in the insect gut. Thus, for an effective pest management, it is imperative to understand the digestive enzymes present in the pest. The present study involves the characterization of mustard aphid α-amylase and the efficacy of a potent insecticidal agent, RiD (Rorippa indica defensin) against it. The total protein of L. erysimi was analysed to determine the α-amylase activity present in it. The relative α-amylase activity in the total protein was assayed by the dinitrosalicylic acid (DNS) procedure, using 1% soluble starch as substrate and was observed to be 2.32?±?0.025?U/mL of the total protein. The optimum temperature for α-amylase activity was found to be 35?°C and optimum pH was recorded as 6.5. Presence of RiD showed a decrease in the α-amylase activity in a non-competitive way. Moreover, cryo-sections of the aphid midgut also revealed bound RiD in the confocal analysis.     

Effects of Cry1Ac toxin of Bacillus thuringiensis and nuclear polyhedrosis virus of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) on larval mortality and pupation

In the laboratory, the percentage mortality and pupation of Helicoverpa armigera (Hübner) were investigated when larvae were exposed to Cry1Ac of Bacillus thuringiensis Berliner, nuclear polyhedrosis virus of H. armigera (HaNPV) or Cry1Ac and HaNPV together. The results revealed that interactions between Cry1Ac and HaNPV varied with bioassay method and concentration of the suspension. When larvae were infected using a suspension containing both HaNPV and Cry1Ac, most combinations of Cry1Ac (62.5, 125 and 250 microg mL(-1)) and HaNPV (1.2 x 10(6), 6.0 x 10(6) and 3.0 x 10(7) PIB mL(-1)) showed an antagonistic effect. In the bioassay procedure where larvae were force fed diet containing Cry1Ac 48 h after being infected by HaNPV, interaction between Cry1Ac (0.5, 1, 2, 4 and 8 microg mL(-1)) and HaNPV (6.0 x 10(6) and 3.0 x 10(7) PIB mL(-1)) showed an additive effect, while combinations of Cry1Ac (0.5, 1, 2 and 4 microg mL(-1)) and HaNPV (1.2 x 10(6) PIB mL(-1)) showed an antagonistic effect. In the bioassay procedure where larvae being infected by HaNPV were fed on Cry1Ac diet from neonate to death or pupation, the results suggested that Cry1Ac and HaNPV showed an additive interaction. The percentage mortality was lower in the treatment of larvae infected by transgenic Bt cotton leaf discs containing HaNPV suspension than in the treatment of larvae by conventional cotton leaf discs containing HaNPV, while the pupation rate was higher. The combination of Bt cotton and HaNPV showed antagonism. The present results showed that a combination of Cry1Ac and HaNPV usually resulted in mortality levels greater than in the case of Cry1Ac but not greater than with the virus alone.     

Effects of nC24 and nC27 petroleum spray oils on oviposition and egg survival of Ostrinia nubilalis Hübner (Lepidoptera,Pyralidae) and Trichogramma brassicae Bezdenko (Hymenoptera,Trichogrammatidae) adults on maize plants

Abstract

The study determined the effectiveness of nC24 and nC27 petroleum spray oils (PSOs) to reduce oviposition of Ostrinia nubilalis and survival of O. nubilalis eggs and Trichogramma brassicae adults. Under choice and no-choice tests, maize treated with 3, 5 and 10% (v/v) of both oils deter O. nubilalis oviposition on maize. The study also showed that treatment of 1 – 3-day-old O. nubilalis eggs with 1 and 2% (v/v) nC24 oil caused 6% mortality compared with 99.5% when treated with 3, 5 and 10% (v/v) oil. In contrast, treatment with 1 – 10% (v/v) nC27 oil caused 99% mortality. Trichogramma brassicae is a major parasitoid of O. nubilalis. The mortality of T. brassicae 24 h after exposure to maize sprayed with 2% (v/v) nC24 and nC27 oils was 8.3 and 12.7%, respectively. At 5% (v/v), the mortalities were 24.9 and 23.5%, respectively. Therefore, application of 3% (v/v) PSO may deter O. nubilalis egg lay, egg mortality and survival of T. brassicae on maize.     

Males of Ichthyofilaria argentinensis Incorvaia, 1999 and I. bergensis (Wülker, 1930) (Dracunculoidea:Guyanemidae): new morphological aspects and emendation of the generic diagnosis

Abstract: The adult male of dracunculoid nematode Ichthyofilaria argentinensis Incorvaia, 1999 (Guyanemidae) is described for the first time based on specimens found in the swimbladder of its type host, Merluccius hubbsi Marini (Merlucciidae), caught off the coast of Buenos Aires, Argentina (western Atlantic Ocean). In addition, the males of Ichthyofilaria bergensis (Wülker, 1930) K?ie, 1993 are redescribed from specimens collected from the body cavity and visceral surface of Molva macrophthalma (Rafinesque) (Lotidae) caught in the western Mediterranean Sea, off the coast of Sardinia. Light and scanning electron microscopy examinations revealed some new morphological features for the genus, such as a pair of deirids located near the end of muscular oesophagus, the body wall conspicuously twisted immediately anterior to the cloaca, the presence of a copulatory plate, one pair of adcloacal papillae and a pair of phasmids situated on the posterior half of the tail. On the basis of this material, the generic diagnosis of Ichthyofilaria is modified to include some of these newly observed features, as well as to indicate the absence of spicules. The diagnosis of Guyanemidae is extended to include that a copulatory plate and/or two spicules may be present as characteristics for this family.     

《生物防治(一)～(四)》介绍

为适应国内生物防治工作的需要,自1977年以来,由中国科学技术情报研究所重庆分所编辑,科学技术文献出版社重庆分社出版了《生物防治》文集,至今已出版了四集,基本上每年一本。本书的特点之一是内容比较广泛。四集共有文章67篇,除有关生物防治的进展、动     

索引(一)

(按农药登记证号)LS 200019金都尔原药批准正式登记的国外农药产品 (包括变更登记)续展临时登记的国外农药产品PD 327一2000LS 93002PD 328一2000高特克5。%悬浮剂(重量/容量)农地乐52.25%乳油(重量/容量)高特克原药精禾草克原药LS 95001PD 329一2000PD 330一2000LS 95016LS 96