| dc.contributor.advisor | Dr. Md. Adnan Al Bachchu | |
| dc.contributor.author | RANA, MD. SHAHIN | |
| dc.date.accessioned | 2022-04-24T05:55:23Z | |
| dc.date.available | 2022-04-24T05:55:23Z | |
| dc.date.issued | 2014-12 | |
| dc.identifier.uri | http://localhost:8080/xmlui/handle/123456789/739 | |
| dc.description | Rice is the staple food for the 145 million people of Bangladesh (DAE 2011). Two
hundred sixty six insect species have been identified so far as pests of rice in Bangladesh
(Islam et al. 2003) and 42 species are considered as important. Insect pests that can cause
significant yield losses in rice are stem borers, leaf hoppers and plant hoppers etc.
Among the plant hoppers, brown plant hopper (Nilaparvata lugens Stal.)
(HOMOPTERA: DELPHACIDAE) is one of the serious problem to rice cultivation in
Bangladesh. This pest is now-a days a major rice pest in South and South-east Asia. It
was formerly a minor pest in most tropical countries of Asia. Widespread adoption of
high-yielding cultivars susceptible to N. Jugens, application of high levels of nitrogen
fertilizers, continuous cropping, and injudicious use of insecticides in the 1960's have
been reported as causes for increased brown plant hopper population and outbreak
(Chelliah and Heinrichs 1984). Nymphs and adults congregate at the base of the plant
and suck plant sap from stem and leaf sheath. BPH damages rice directly through
feeding and also by transmitting two viruses, rice ragged stunt virus and rice grassy stunt
virus. BPH infest the rice crop at all stages of plant growth. As a result of feeding plants
turn yellow and dry up rapidly. At early infestation, round, yellow patches appear, which
soon turn brownish due to the drying up of the plants. This condition is called 'hopper
burn’. Sometimes the damage may be so great that growers have to abandon the crop.
The loss in grain yield ranges from 10% in moderately affected fields to 70% in those
fields which are severely affected (Ghosh ef al. 2013). | en_US |
| dc.description.abstract | The investigation was made to evaluate the effectiveness of nonchemical management
practices against brown plant hopper (BPH), Nilaparvata lugens (Stal.). The treatments
of the cultural practices were three different levels of Urea fertilizer application and three
different seedling spacing. The experimental results showed that the number of BPH was
increased with the increased of days after transplanting in both treatments. The highest
number of nymphs and adults were recorded at maximum doses (225 kg/ha) of urea
fertilizer application and closer seedling spacing at 75 day after transplanting while the
lowest number was observed in minimum doses with maximum wider seedling spacing
at 30 days after transplanting in both locations. The methanol solvent extracts at 0.5, 1.0
and 1.5 % concentration of six plants were evaluated for their toxic effects against
nymph and adult of brown plant hopper. The results revealed that all six plant extracts
had different toxic effects against BPH. Chili plant extract showed the highest toxic
effect whereas castor showed the lowest toxic effect against both the nymphal and adult
stages. Mortality percentage was also found directly proportional to the level of
concentrations of plant extracts and to the exposure period. All the doses of six tested
plant extracts were found to be excellent mortality of both the nymph and adult at
different time intervals (30, 45, 60 and 75 DAT) and were effective at higher dose. The
lowest LDs value also indicated that the chili leaf extract is highly effective against the
nymph and adult of BPH. The results clearly indicate that the plant based pesticide
containing low lethal concentration can be used effectively to control the BPH. | en_US |
| dc.language.iso | en | en_US |
| dc.publisher | HAJEE MOHAMMOD DANESH SCIENCE AND TECHNOLOGY UNIVERSITY, DINAJPUR | en_US |
| dc.subject | Urea fertilizer | en_US |
| dc.subject | spacing | en_US |
| dc.subject | plant extract | en_US |
| dc.subject | methanol | en_US |
| dc.subject | mortality | en_US |
| dc.subject | BPH | en_US |
| dc.title | EVALUATION OF NONCHEMICAL MANAGEMENT PRACTICES AGAINST BROWN PLANT HOPPER, NILAPARVATA LUGENS (STAL.) (HOMOPTERA: DELPHACIDAE) | en_US |
| dc.type | Thesis | en_US |
