http://103.7.193.12:8080/xmlui/handle/123456789/256 2026-04-17T15:36:34Z 2026-04-17T15:36:34Z TAJ, HASAN FUAD EL http://103.7.193.12:8080/xmlui/handle/123456789/1872 2022-05-18T07:43:14Z 2009-08-01T00:00:00Z

BIOLOGICAL CHARACTERS OF KOREAN NEOSEIULUS CALIFORNICUS MCGREGOR (ACARI: PHYTOSEITDAE) IN RELATION TO ENVIRONMENTAL PARAMETERS TAJ, HASAN FUAD EL Spider mite is one of the most important pests of apple in Korea. Two spotted spider mite and European red mite are the most common in apple and they are in competition. Recently European red mite is becoming dominant over two spotted spider mite in Korean apple orchards. As the acaricide application has been the most option employed to control spider mites and as wide range of acaricide resistances have been the concerns, alternative control options are in demand. Biological control of spider mites by predatory mites has been tried on a wide range of crops including apples. This study examined the feasibility of using a Korean isolate Neoseiulus californicus (Acari: Phytoseiidae) as a potential biological control agent in apple orchards in the mainland Korea. The distribution of this naturally occurring predatory mite is restricted only to the southern, warmer island, Jeju but not in the relatively cooler main domain of Korea. Scanty of information is available on the biological characters and overwintering phenology of this native predator. Temperature effect on life history parameters of N. californicus using Panonychus ulmi was experimented to evaluate the suitability of this predatory mite for controlling apple mites. The results specified that the developmental time is decreased with increasing temperature between 15 and 30°C. At 25°C, females laid maximum number of eggs. The highest net reproductive rate (Ry = 49.24) and the intrinsic rate of natural increase (r,, = 0.29) were found at 25 and 30°C, respectively. Environmental 126 tolerance of Neoseiulus californicus was compared to the native dominant phytoseiid, Neoseiulus womersleyi and the introduced, most widely used phytoseiid, Phytoseiulus persimilis (Phytoseiidae) by treating combination of temperatures and relative humidity for egg hatching, immature survival, and adult female performance. Korean N. californicus was most tolerant to high temperature and low humidity, N. womersleyi was more humid susceptible and P. persimilis showed high temperature susceptible with high reproductive ability. While food limited, cannibalism was higher in N. californicus and they may get benefit for their survival. Overwintering phenology was studied with a view to establish this predator in the lion cooler part of Korea. As a part of overwintering phenomena, diapause propensity of the native predator was measured and diapause induction was not found in N. californicus isolated from Korea. Cold tolerance of the Korean WN. californicus was also measured as the non-diapausing population can survive up to certain limit of cold temperatures for a certain period. The survivorship of this predator at all subzero temperatures could assume the possibility to establish in the main domain. A DISSERTATION FOR THE DEGREE OF DOCTOR OF PHILOSOPHY © — BIOLOGICAL CHARACTERS OF KOREAN NEOSEIULUS CALIFORNICUS MCGREGOR (ACARI: PHYTOSEITDAE) IN RELATION TO ENVIRONMENTAL PARAMETERS BY HASAN FUAD EL TAJ MAJOR IN APPLIED ENTOMOLOGY DEPARTMENT OF BIORESOURCE SCIENCES THE GRADUATE SCHOOL ANDONG NATIONAL UNIVERSITY AUGUST, 2009

2009-08-01T00:00:00Z DAS, AMAL KUMAR http://103.7.193.12:8080/xmlui/handle/123456789/1218 2022-04-27T08:24:59Z 2019-06-01T00:00:00Z

INSECT POPULATION DYNAMICS AND MANAGEMENT STRATEGIES OF STEMFLY, OPHIOMYIA PHASEOLI (TRYON) (DIPTERA: AGROMYZIDAE) IN SOYBEAN DAS, AMAL KUMAR The research work on population dynamics of insects and management strategies of stem fly Ophiomyia phaseoli (Tryon) (Diptera: Agromyzidae) in soybean was carried out at the Breeder Seed Production Center, BARI, Debiganj, Panchagarh, during August 2014 ˗ December 2017. Twenty four insect species were found in soybean field. Of them only eight species were considered as the major pests, while the rests were minor importance on the basis of population density per plant, % infested plant and stem tunneling. The succession of insect pests was found in an overlapping manner and the crop was under continuous attack by one or more pests. Most of the major and minor pests appeared during vegetative and flowering stages (35˗ 45 DAS). The stage of crop had greater influence on the incidence of the pest. Irrespective of sowing times, pest population was first detected from 2nd week after sowing. Cent percent plant became affected at three weeks of plant age. The stem fly infestation was significantly lower in protected plot as compared to unprotected plot. Plant growth, yield and yield contributing parameters were influenced significantly by the pest. The avoidable yield loss was estimated 24.04%. Twelve soybean variety/lines were evaluated to determine their performance for tolerant against stem fly. The lines Culombus and LG-92P-1825 showed the least infestation (47.44, 50.89% plant infestation and 13.33, 14.94% stem tunneling/plant, respectively). The experiment indicated that intercropping of soybean played a vital role against stem fly infestation and yield of soybean. Intercropped soybean with sesame, groundnut and coriander reducing 45.93, 40.42, 39.35% plant infestation and 56.55, 52.14, 44.27% stem tunneling over control, respectively. The highest benefit cost ratio (1.55) was achieved from sesame intercropped plot. The experiment was conducted to develop an effective management of stemfly in soybean using three insecticides and four botanical origins. The results revealed that Carbofuran + Nitro 505 EC (12.33% plant infestation and 5.27% stem tunneling) was the most effective control approach against stemfly. Regarding seed yield, significantly the highest yield (1.97 t/ha) was harvested when Carbofuran (Furadan 5 G) was applied as seed treatment and Nitro spraying but it gave statistically similar result to Nitro (1.92 t/ha) and seed treatment with Carbofuran (1.91 t/ha). A Thesis Submitted to The Department of Entomology Hajee Mohammad Danesh Science and Technology University Dinajpur in partial fulfillment of the requirement for the degree of DOCTOR OF PHILOSOPHY (Ph.D.) IN ENTOMOLOGY

2019-06-01T00:00:00Z