Biological control of Bemisia tabaci in Korea: Status and prospects

Hwang-Yong Kim,Jeong-Hwan Kim,Yong-Heon Kim,Yong-Hwi Lee 한국응용곤충학회 2008 한국응용곤충학회 학술대회논문집 Vol.2008 No.10

In 2005, the invasion of Bemisia tabaci Q-type was detected at first in the southern part of Korea. And then the pest has been spread rapidly over the nation, and it has attacked various fruit vegetables including yellow melon, tomato, sweet pepper, and so on. During three years since 2005, many kinds of predators and parasitoids have been applied to establish the biological control program to solve the Bemisia tabaci problem. Parasitoids were regarded as promising natural enemies, at first. However, Encarsia formosa famous for the parasitoid of greenhouse whitefly is not so effective to control Bemisia tabaci. Although other parasitoids, Eretmocerus eremicus and Eretmocerus mundus, were introduced successively, application results of them were not satisfactory. Owing to the difficulties in settling the parasitoids on crops, total cost of biological control program tends to be increased by the iterative periodic release. On the other hand, it was great that the application result of predatory mite, Amblyseius swirskii. Laboratory experiments show that the mite can consume large amount of Bemisia tabaci eggs. In addition, the mite can survive and reproduce without prey. Plant-associated materials such as pollens are sufficient for the development and reproduction of the mite. Field observations reveal that just onetime release after the first blossom is enough for the preventive treatment. The mite is especially so effective on the pollen-rich crops such as sweet pepper. Flowers and leaves are infested by the mite in a brief instant. While flower-dwelling mites take a role of natural enemy of thrips, leaf-dwelling mites effectively suppress the density of Bemisia tabaci. Anyway, curative treatment of the mite is not desirable, for it usually do not feed on other stage of Bemisia tabaci except fresh eggs within one or two days. It is also unfortunate that the mite seldom moves on tomato. It is even reluctant to go out from distribution box. When we put some mites on a leaf of tomato, they usually aggregated in a point. Sticky trichomes and semiochemicals might be engaged in such phenomena. In addition, the mite seems to be suffered by high temperature. So the density of Bemisia tabaci could be increased continuously in summer season, regardless of the presence of the predatory mite. In recent, we keep an eye on another predatory bug, Nesidiocoris tenuis, as a biological control agent against whiteflies on tomato. Nesidiocoris tenuis is an active and aggressive natural enemy. It likes to eat whitefly eggs, larvae and pupae. It can also feeds on aphids and mites. Once established in tomato greenhouse, whiteflies were overwhelmed by the predator. In our observation, Bemisia tabaci could be successfully controlled by the predator without any pesticide application, during about a half year from early spring to mid summer. However, we should take precaution against the side effects of Nesidiocoris tenuis, which is ironically known as a serious pest on tomato. From time to time, growing points of tomato could be disappeared by the damage of Nesidiocoris tenuis. So we need to control the density of the bug under the economic threshold. Owing to the bug, the production of sesame could be decreased remarkably. To avoid side effects, Nesidiocoris tenuis should be handled by the experts who know well about the ecological characteristics of it. In the case of yellow melon, biological control of any pest is not easy task. Without pesticide, yellow melon is frequently damaged destructively by aphids, mites and whiteflies. However, the temperature in greenhouse is too high to release and augment ordinary natural enemies. We just regard Nesidiocoris tenuis as a promising natural enemy of whiteflies on yellow melon, because it is resistant to high temperature. Many trials and errors might be required to establish reliable strategy to solve the problem caused by Bemisia tabaci. And it should be continued that the efforts for the integrated pest management based on biological control.

Farmers’ Knowledge and Practices in Controlling Mites and Their Attitude Towards Biological Control

Nguyen Duc Tung,Celia DR. Medina,Luis Rey I. Velasco,Josefina T. Dizon 한국국제농업개발학회 2011 韓國國際農業開發學會誌 Vol.23 No.1

The study was conducted to determine the knowledge and practices of vegetable farmers in Hanoi, Vietnam in controlling mites, and their attitude towards N. longispinosus as biological control agent against T. urticae on green bean. The field surveys conducted in Tang My and Son Du hamlets, two of the largest vegetable production areas in Dong Anh district, show that the respondents in Tang My who had training on the vegetable IPM program had higher knowledge on green bean pest management and knew better about natural enemies and biological control than the ones without training in Son Du. However, both groups of respondents did not have enough knowledge on spider mite control and most of them did not know or hear about predatory mite before. Hence, 40 percent of the respondents said they would not use predatory mites, and 33 percent were still uncertain whether they will adopt this biological control. The paper suggests some recommendations to enhance farmers’ use of biological control against mites on green beans.

Research Papers : Farmers` Knowledge and Practices in Controlling Mites and Their Attitude Towards Biological Control

( Nguyen Duc Tung ),( Celia Dr. Medina ),( Luis Rey I. Velasco ),( Josefina T. Dizon ) 한국국제농업개발학회 2011 韓國國際農業開發學會誌 Vol.23 No.1

The study was conducted to determine the knowledge and practices of vegetable farmers in Hanoi, Vietnam in controlling mites, and their attitude towards N. longispinosus as biological control agent against T. urticae on green bean. The field surveys conducted in Tang My and Son Du hamlets, two of the largest vegetable production areas in Dong Anh district, show that the respondents in Tang My who had training on the vegetable IPM program had higher knowledge on green bean pest management and knew better about natural enemies and biological control than the ones without training in Son Du. However, both groups of respondents did not have enough knowledge on spider mite control and most of them did not know or hear about predatory mite before. Hence, 40 percent of the respondents said they would not use predatory mites, and 33 percent were still uncertain whether they will adopt this biological control. The paper suggests some recommendations to enhance farmers` use of biological control against mites on green beans.

Study on the field propagation of Pteromalus sanjiangyuanicus Yang and its biological control of Gynaephora qinghaiensis

Wang Haizhen,Zhang Jianshuang 한국응용곤충학회 2023 Journal of Asia-Pacific Entomology Vol.26 No.4

Gynaephora qinghaiensis is an important pest that damages alpine meadow vegetation in Qinghai-Tibet Plateau (QTP) alpine pastoral areas. Pteromalus sanjiangyuanicus Yang is a parasitic natural enemy of pupal G. qinghaiensis. For biological control of G. qinghaiensis, local materials and G. qinghaiensis were used for P. sanjiangyuanicus propagation. Under natural field conditions, P. sanjiangyuanicus were propagated in artificial nests. Propagated P. sanjiangyuanicus were then released into the experimental area, where the G. qinghaiensis density was high, and the biological control effect was evaluated. In the propagation test plot (D), the average P. sanjiangyuanicus parasitism rate was 70.3% (46.3–87.0%). The P. sanjiangyuanicus parasitism rate in the experimental area was significantly higher than that in the control area, and the propagation effect was good. The P. sanjiangyuanicus parasitism rates in the biological control plots (A, B, and C) increased yearly from 2016 to 2019, indicating that the P. sanjiangyuanicus population size in the biological control area increased yearly and that the parasitoid population size effectively increased. From 2016 to 2019, the G. qinghaiensis population decline rates in the biological control plots (A, B and C) were 71.1%, 59.3% and 76.4%, respectively (average 68.9%). The control effects on G. qinghaiensis were 80.9%, 69.9% and 80.3%, respectively (average 77.0%). The results showed that P. sanjiangyuanicus was effective in controlling G. qinghaiensis. This study provides a reference for the large-scale propagation of P. sanjiangyuanicus and the further promotion and application of G. qinghaiensis biological control.

Biologically Inspired Controller for Planar Biped Robot Gait Based on Functional Model of Human Locomotion System

Hooman Homayouni,Fariba Bahrami,Caro Lucas 제어로봇시스템학회 2008 제어로봇시스템학회 국제학술대회 논문집 Vol.2008 No.10

Inspired by human locomotion system, we have proposed a gait controller for planar walking of a biped robot. On the basis of biomechanical and neurophysiologic studies of human gait, a two-layer controller is proposed. Lower layer of the controller consists of models of three neural mechanisms identified in the spinal cord: cutaneous reflex, stretch reflex, and central pattern generator (CPG). Upper layer controller maintains stability of the robot by employing fuzzy rule-based approach in applying two main strategies derived from biomechanical studies of human locomotion, that is ankle torque control and foot placement adjustment. Proposed controller does not require precise model of the mechanical system of the robot. Simulation results prove the capability of the proposed controller to generate a stable planar biped gait for the model robot. Stable limit-cycle for kinematic variables emerges from interaction of mechanical system with low-level mechanisms and high-level fuzzy controller. In facing disturbances, in form of a push from both front and behind, robot shows great ability to maintain its balance. This balance control is provided by the upper layer rule-based controller.

Efficacy of Chaetomium Species as Biological Control Agents against Phytophthora nicotianae Root Rot in Citrus

( Phung Manh Hung ),( Pongnak Wattanachai ),( Soytong Kasem ),( Supattra Poeaim ) 한국균학회 2015 Mycobiology Vol.43 No.3

Thailand is one of the largest citrus producers in Southeast Asia. Pathogenic infection by Phytophthora, however, has become one of major impediments to production. This study identified a pathogenic oomycete isolated from rotted roots of pomelo (Citrus maxima) in Thailand as Phytophthora nicotianae by the internal transcribed spacer ribosomal DNA sequence analysis. Then, we examined the in vitro and in vivo effects of Chaetomium globosum, Chaetomium lucknowense, Chaetomium cupreum and their crude extracts as biological control agents in controlling this P. nicotianae strain. Represent as antagonists in biculture test, the tested Chaetomium species inhibited mycelial growth by 50~56% and parasitized the hyphae, resulting in degradation of P. nicotianae mycelia after 30 days. The crude extracts of these Chaetomium species exhibited antifungal activities against mycelial growth of P. nicotianae, with effective doses of 2.6~101.4 μg/mL. Under greenhouse conditions, application of spores and methanol extracts of these Chaetomium species to pomelo seedlings inoculated with P. nicotianae reduced root rot by 66~71% and increased plant weight by 72~85% compared to that in the control. The method of application of antagonistic spores to control the disease was simple and economical, and it may thus be applicable for large-scale, highly effective biological control of this pathogen.

세포성 면역 알고리즘을 이용한 AGV의 조향 제어기 설계에 관한 연구

이영진,이진우,이권순,Lee, Yeong-Jin,Lee, Jin-U,Lee, Gwon-Sun 제어로봇시스템학회 2001 제어·로봇·시스템학회 논문지 Vol.7 No.10

The PID controller has been widely applied to the most control systems because of its simple structure and east designing. One of the important points to design the PID control system is to tune the approximate control parameters for the given target system. To find the PID parameters using Ziegler Nichols(ZN) method needs a lot of experience and experiments to ensure the optimal performance. In this paper, CMIA(Cell Mediated Immune Algorithm) controller is proposed to drive the autonomous guided vehicle (AGV) more effectively. The proposed controller is based on specific immune responses of the biological immune system which is the cell mediated immunity. To verify the performance of the proposed CMIA controller, some experiments for the control of steering and speed of that AGV are performed. The tracking error of the AGV is mainly investigated for this purpose. As a result, the capability of realization and reliableness are proved by comparing the response characteristics of the proposed CMIA controllers with those of the conventional PID and NNPID(Neural Network PID) controller.

Nonlinear Model-based Dissolved Oxygen Control in a Biological Wastewater Treatment Process

유창규,이종민,이인범 한국화학공학회 2004 Korean Journal of Chemical Engineering Vol.21 No.1

The dissolved oxygen (DO) concentration has been an important process parameter in the biological wastewater treatment process (WWTP). In this paper, we propose a nonlinear control scheme to maintain the dissolved oxygen level of an activated sludge system. Without any linearization or model reduction, it can directly incorporate the nonlinear DO process model with on-line estimation of the respiration rate (R) and the oxygen transfer rate (KLa). Simulation results show that it outperforms a control performance of the PID controller. Since it incorporates the process disturbance and nonlinearity in the controller design, the suggested method can efficiently deal with the operating condition changes that occur frequently in the wastewater treatment process.

Trichoderma harzianum ABGC-95를 이용한 골프그린에 발생하는 Pythium 마름병의 생물적 방제

염주립 한국잔디학회 1999 한국잔디학회지 Vol.13 No.4

Antibiotic activity of selected biocontrol agent Trichoderma harzianum ABGS-95 showed 59% to P. graminicola, 65% to P. aphanidermatum and 57% to Rhizoctonia solani compare to non-treated control. ABGC-95 showed resistant to major agrochemicals such as metalaxyl+mancozeb, etridiazole, propamocarb, toclofos methly, terbuconazole, pencycuron and flutolanil. The biocontrol agent T. harzianum ABGC-95 grew vigorously in low nutrient media and water agar. And sand mixture with wheat bran or mowing debris of zoysia grass also provided good growth of the organism. Application of sand mixture of Trichoderma spp. into aeration cores in golf showed most effective biocontrol of pythium blight. Top dressing application of T. harzianum ABGC-95 reached 83% control efficient while spray application of same biocontrol agent showed only 69% control. The biocontrol agent ABGC-95 successfully suppressed the population density of Pythium spp. in soil. The population density of total Pythium spp. in ABGC-95 treated soil was sustained almost same population at beginning(early May) up to end of August, while the population in untreated control plot was increased 5 times that of beginning and even 10 times in pathogen accumulated soil.

길항세균을 이용한 인삼병의 생물학적 방제

김선익,최봉규,김현호,양계진 中部大學校 自然科學硏究所 1999 自然科學硏究論文集 Vol.8 No.1

인삼 토양병의 생물학적 방제를 위하여 인삼 근권토양에서 길항세균을 분리. 선발 하였으며 선발된 길항세균을 인삼종자와 유묘에 처리한 다음 실내 및 포장시험을 통해 생물학적 방제의 가능성을 조사하였다. 인삼근권토양으로부터 56개의 길항세균을 분리하였는데, 고년근일수록 인삼근권토양에서 길항세균의 분리빈도는 적었다. 작물에 비병원성이며 저온, 저영양조건에서 Botrytis cinerea, Fusarium solani, Cylindrocarpon destructans, Alternaria panax, Rhizoctonia solani, Phyeophthora cactorum 그리고 Pythium sp. 균에 항균활성을 보이는 B2, B12, 17N6-1, S21, 16P5균주가 유용 길항세균으로 선발되었다. Rhizoc- tonia solani의 방제를 위한 포트시험 결과 S21균주와 16P5균주가 우수하였으며, S21균주는 Botrytis cinerea에 대한 방제가 46.4%로 가장 효과가 높았다. 인삼종자의 Bacterization 효과에 대한 포장 검정에서 S21, 16P5, 및 17N6-1균주가 인삼의 뿌리썩음병 방제에 매우 효과적이었고, 담체로는 Perlite와 Talc가 좋았다. Isolation and selection of antagonistic rhizobacteria were performed for biological control on soil-borne disease of ginseng in pot and field trials, and to analyse enchance conditions for antibiotic activity and colonization in rhizosphere, this study was conducted. 56 strains of antagonistic rhizobacteria were isolated from rhizosphere soils of ginseng fields. frequency of its occurrence was low with agd of ginseng. B2, B12, 17N6-1, S21 and 16P5 strain were selected as beneficial antagonistic bacteria based on results from pathogenicity test on ginseng and other crops, and test of antagonistic effect on major pathogens of ginseng. these strains could grow well under the low temperature and low nutrition condition. In pot trials for control of Rhizoctonia solani. S21 and 16P5 strain had much better antibiotic activity. in addition S21 strain also showed high control value on Botrytis cinerea. Three strains, S21, 16P5, 17N6-1, were very effect for root rot disease control by seed bacterization in field trials. Perlite and talc were better as a coating material for control.