植保无人机施药对玉米草地贪夜蛾的防治效果

采用植保无人机和机动喷雾器2种施药方法,开展了氯虫苯甲酰胺、茚虫威2种农药对玉米草地贪夜蛾的田间防效试验。结果表明,采用2种施药械施药对2种农药的田间防效均没有显著差异。200g/L氯虫苯甲酰胺悬浮剂15mL/667m 2药后7d防效最高,植保无人机施药和机动喷雾器施药防效分别为89.0%、91.8%,叶片保护率分别为86.5%、88.3%。150g/L茚虫威乳油18mL/667m 2药后3d防效最高,植保无人机施药和机动喷雾器施药防效分别为85.5%、85.2%,叶片保护率分别为75.8%、76.4%。茚虫威表现出较好的速效性,氯虫苯甲酰胺表现出更长的持效性。     

Protective effect of vitamin C against chlorpyrifos oxidative stress in male mice

Pesticides may induce oxidative stress leading to generate free radicals and alternate antioxidant or oxygen free radical scavenging enzyme system. This study was conducted to investigate the acute toxicity of chlorpyrifos toward male mice and the oxidative stress of the sub-lethal dose (1/10 LD₅₀) on the lipid peroxidation level (LPO), reduced glutathione content (GSH) and antioxidant enzymes; catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glucose-6-phosphate dehydrogenase (G6PD), and glutathione-S-transferase (GST) activities. Also, the protective effects of vitamin C (200 mg/kg body weight, bw) 30 min before or after administration of chlorpyrifos were investigated. The results demonstrated that the LD₅₀ value of chlorpyrifos was 134.95 mg/kg bw. The oral administration of 13.495 mg/kg chlorpyrifos significantly caused elevation in LPO level and the activities of antioxidant enzymes including CAT, SOD and GST. However, GPx activity remained unchanged, while the level of GSH and G6PD activity were decreased. Vitamin C treatment to chlorpyrifos intoxicated mice decreased LPO level and GST activity, normalized CAT, SOD and G6PD activities, while GSH content was increased. We conclude that vitamin C significantly reduces chlorpyrifos-induced oxidative stress in mice liver and the protective effect of the pre-treatment with vitamin C is better than the post-treatment.     

Protection of susceptible potato cultivars against late blight in mixtures increases with decreasing disease pressure

ABSTRACT Cultivar mixtures can reduce potato late blight severity on susceptible cultivars. While alternating rows of susceptible and resistant cultivars would be more acceptable than random mixtures for commercial use, they increase the genotype unit area, which is an unfavorable factor for mixture efficiency, and have been minimally efficient when disease pressure is high. The effects of disease pressure on the performance of alternating rows of cultivars possessing various types and levels of resistance were investigated in 2000 and 2001 near Quito, Ecuador, where natural pressure of late blight is high. The experiments included the highly susceptible cvs. Cecilia in 2000 and LBr37 in 2001, as well as C114 (moderately resistant) and PAN (highly resistant), planted as pure stands and as the three possible two-way combinations. Different disease pressures were obtained with three spraying schedules of a contact fungicide: nontreated, one spray every second week, and one spray weekly. The area under the disease progress curve (AUDPC) on the susceptible cultivar was 0 to 20% less in mixed than in pure plots when no fungicide was applied, 13 to 26% less with a biweekly application of fungicide, and 32 to 53% less with a weekly application. These values are comparable to those obtained in previous experiments in smaller plots with designs maximizing the distance between susceptible plants. No significant differences in mixture performance were observed according to the resistant cultivar included. Effects on yield were minimal, because of the impact of factors other than late blight. Disease pressure therefore appears as a major factor conditioning the efficiency of potato cultivar mixtures against late blight.     

Protection of olive planting stocks against parasitism of root-knot nematodes by arbuscular mycorrhizal fungi

The effects were investigated, under controlled conditions, of single and joint inoculation of olive planting stocks cvs Arbequina and Picual with the arbuscular mycorrhizal fungi (AMF) Glomus intraradices , Glomus mosseae or Glomus viscosum , and the root-knot nematodes Meloidogyne incognita and Meloidogyne javanica , on plant performance and nematode infection. Establishment of the fungal symbiosis significantly increased growth of olive plants by 88·9% within a range of 11·9–214·0%, irrespective of olive cultivar, plant age and infection by M. incognita or M. javanica . In plants free from AMF, infection by Meloidogyne spp. significantly reduced the plant main stem diameter by 22·8–38·6%, irrespective of cultivar and plant age. Establishment of AMF in olive plants significantly reduced severity of root galling by 6·3–36·8% as well as reproduction of both Meloidogyne spp. by 11·8–35·7%, indicating a protective effect against parasitism by root-knot nematodes. Infection by the nematodes influenced root colonization by AMF, but the net effect depended on the AMF isolate–olive cultivar combination. It is concluded that prior inoculation of olive plants with AMF may contribute to improving the health status and vigour of cvs Arbequina and Picual planting stocks during nursery propagation.     

Protection against bacterial soft rot by olive extracts is related to general defence induction in potato tubers

Controlling bacterial plant diseases remains a challenge, as direct chemical control is usually not possible. Obtaining new biocontrol methods, in particular efficient biomolecules able to boost defence reactions and limit infection or symptom development, is therefore of major importance. This study screened extracts from leaves of two Mediterranean plants rich in bioactive phenolic compounds, olive and carob, for their ability to reduce soft rot severity and to trigger phenylalanine ammonia‐lyase (PAL) activity in potato tuber slices. Extracts from olive leaves significantly reduced disease severity caused by Pectobacterium atrosepticum or Pectobacterium carotovorum, whereas carob leaf extracts significantly increased it. Olive extracts and its main phenolic components, oleuropein and hydroxytyrosol, also significantly increased PAL activity 7.5 h after application. None of the extracts or purified molecules reduced bacterial growth in vitro. Furthermore, the effect of these extracts varied according to potato cultivars. These data therefore open new ways for the biological control of soft rot bacteria, but stress the importance of understanding the causes of response difference in different potato varieties in order to obtain optimal efficacy.     

Protection of cucumber against Pythium root rot by fluorescent pseudomonads: predominant role of induced resistance over siderophores and antibiosis

Four Pseudomonas strains were evaluated for their intrinsic properties conferring their ability to protect long English cucumber against Pythium aphanidermatum in hydroponic culture. Two of the strains, BTP1 and its siderophore-negative mutant M3, increased plant yield as compared with the non-inoculated control plants. Strain BTP7 was intermediate in its biocontrol activity while strain ATCC 17400 failed to reduce disease development. The role of pyoverdines could not be confirmed since treatment with either BTP1 or its siderophore-negative mutant M3 provided similar suppression of Pythium disease. In addition, no siderophores were detected in the nutrient solution. BTP1 did not inhibit pathogen growth in vitro on several media, suggesting that antibiosis was not a mechanism of suppression. Quantification of root bacterial populations did not indicate differences among the strains. On the other hand, roots treated with either BTP1 or its sid⁻ mutant M3 contained more antifungal phenolics than roots from any other treatments including controls. These results suggest that antifungal compounds induced by inoculation of cucumber roots with the fluorescent Pseudomonas strains BTP1 and M3 participate actively in the protection of cucumber plants against P. aphanidermatum     

Evaluation of aspect of some oxidative stress parameters using vitamin E, proanthocyanidin and N-acetylcysteine against exposure to cyfluthrin in mice

A hundred and sixty female white mice, each weighing 35-40 g, were used in this study. The animals were assigned into eight groups as one control group and 7 experimental groups. Groups 2, 3 and 4 were administered N-acetylcysteine (NAC), proanthocyanidin and vitamin E alone, at doses of 100 mg/kg/body weight/day by intra-peritoneal, oral route and, intramuscular, respectively. Group 5 was administered a single dose of cyfluthrin (100 mg g/kg/body weight ∼1/3LD₅₀) by oral, whereas Groups 6, 7 and 8 were given cyfluthrin+NAC, cyfluthrin+proanthocyanidin and cyfluthrin+vitamin E, at the same dose, respectively. The administration of the drugs was initiated following the administration of cyfluthrin, and continued until the end of the seventh day of the study. Blood samples were collected from each group, 24 h, and 3, 7 and 9 days after the administration of cyfluthrin for the assessment of blood malondialdehyde (MDA) levels and superoxide dismutase (SOD) and catalase (CAT) activities. According to the data obtained, compared to the control group, increase in the plasma MDA level of the group administered cyfluthrin alone, and decrease in erythrocyte SOD activities in some periods and CAT activities in all periods were determined. On the other hand, especially, MDA levels and CAT activities were observed to move closer to values of the control group, in the groups that were administered NAC, proanthocyanidin and vitamin E in addition to cyfluthrin. In other words, in most periods, decrease in plasma MDA levels, and increase in erythrocyte CAT and SOD activities were observed in comparison to the group administered cyfluthrin alone. Statistical analyses demonstrated significant differences to exist between the groups on the third, seventh and ninth days with respect to plasma MDA levels, and the third and ninth days with respect to erythrocyte SOD and CAT activities (P < 0.05). However no significant difference was demonstrated in any of the periods in the groups that were administered NAC, proanthocyanidin and vitamin E alone in comparison to the control group (P > 0.05). In view of the parameters examined, animals were concluded to be affected by cyfluthrin and the administration of the three compounds at the indicated doses and for the indicated periods were considered to alleviate the adverse effects of cyfluthrin partly throughout the study period.     

Plant Protection in India: Problems and Prospects

Abstract

Agricultural productivity in India has hardly increased in the past 25 years. Inefficient plant protection services are held responsible to some extent by the author. Suggestions for improvements in surveillance and diagnosis and emphasis on cultural control and safe storage are made with an example from the Saharanpur District.     

Plant Protection and Production in Modern Society1

Many currently existing agricultural production techniques have been developed in total reliance on effective chemical pest control. Today, however, it is becoming clear that chemical pest control has a number of limitations, and its ever increasing costs may well make it a limiting factor in agricultural production. This has already occurred in a number of cotton growing areas. The need for increased world food production will require improved pest control methods. If no special precautions are taken, we will undoubtedly end up in many other crops with a situation similar to that of cotton. In view of the reduced availability of new pesticides, those currently available should be used in the optimal way. At the present time, the integrated pest control approach is the best means of accomplishing this. The introduction of such programs will require official support through legislation or technical assistance. In the future, various new developments in pest control are to be expected. Greater reliance will be placed on the use of computer science. Further effort will be needed in areas such as crop loss assessment, stored product pests, technical assistance to farmers and pesticide selectivity. Closer international collaboration on plant quarantine matters and pesticide registration are essential for the future of pest control.     

新疆天鹅的分布和保护

新疆有三种天鹅,即大天鹅、小天鹅、疣鼻天鹅。大天鹅和疣鼻天鹅是夏侯鸟,小天鹅是迁栖期过客。春季,天鹅最多,估计有10000只,冬季不超过2000只。人类经济活动对天鹅数量影响极大,因而亟须进行保护。     

New Tendencies in Plant Protection

Concern about pesticide residues and the unprofitability of classical treatments through secondary complications has led to a new approach to plant protection problems. Applications must be based on the assessment of their necessity and full account must be taken of the advantages offered by various possibilities of biological control (introduction of parasites or predators, their mass-breeding, genetical control, use of attractants) and other procedures (breeding for resistance, cultural measures). Close co-operation between the various sectors of research involved is recommended.     

推广绿色植保技术是新世纪植保发展的方向

绿色植保技术，是指对农业环境和农产品质量无污染的生物灾害监测控制技术，即环保型的植保技术。推广绿色植保技术，在预防和治理农业生物灾害的同时确保农产品和农业环境不受污染，确保农民经济效益的提高，是传统的数量型自足农业向质量效益型市场农业转变后对植保防灾减灾工作提出的更迫切、更严格的要求，也是新形势下植保科技进步与创新的主攻方向。从河北省农业病虫灾害的发生状况、农民的防治效益和消费者对农产品质量要求看，推行绿色植保势在必行。１推进绿色植保是新世纪植保技术创新与推广的必然趋势１．１推行绿色植保是植保防…     

茶园蜘蛛的控害作用及其保护利用

蜘蛛是茶园害虫的重要天敌类群,具有分布广,数量大,持续时间长,捕食力与抗逆性强等特点.对害虫的自然控制作用大,在害虫防控中起着十分重要的作用.实际工作中应注意对茶园蜘蛛加以保护利用,充分发挥蜘蛛对害虫的控制作用.     

Plant Protection with and without Risks

Conventional plant protection procedures and integrated control are being compared in the light of their profitability. Control measures must be based on the density of pest populations. The fluctuations concerned can be usefully reproduced by means of a mathematic pendulum oscillating over a logarithmical scale of the densities. The model shows that better crop yields can be obtained through a reduced application of chemicals. Moreover, the expenditure incurred in integrated control is less and risks of failure are also lower.     

Research on Plant Protection in Indonesia

Abstract

A protocol for biological control of weeds is described. It consists of preintroductory studies on the distribution and ecology of the weed, the discovery of organisms adapted to it, the estimation of their effectiveness, the selection of the most damaging strain and the examination of their safety as biological control agents and post-introductory studies to obtain establishment of non-infected stocks and to observe their effect on the weed populations.

Recent biological control studies on weeds are shown to support the proposals and the biological basis underlying the proposals is discussed. It is shown that where these have been ignored biological control has not been successful whereas when the protocol has been fully applied the weed has been successfully controlled.     

Organization of Plant Protection in Norway and Research Orientation1

Research in the various crop protection disciplines is carried out at the Central Norwegian Plant Protection Institute near Oslo: it includes studies on pesticide efficacy, problems of uptake, breakdown and residues. This agency is further in charge of the extension of practical knowledge and has a supervising capacity for the Plant Inspection Service. Some of the various problems which are of major concern for Norway are reviewed and ways for a proper integration of chemical and alternative methods studied.