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Score: 18.00 |
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| Title: An aquatic light trap designed for live capture of predatory Tropisternus sp ( Coleoptera : Hydrophilidae ) larvae in Arkansas rice fields .
| | Author: Dennett JA Meisch MV .
| | Journal: J Am . Mosq . Control Assoc .
Citation: V : 17 ( 4 ) P : 268-71 Year: 2001 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11804467 Accession (PMID): 11804467 | | Abstract: Construction of an aquatic light trap developed for the live capture of 3rd-stage larvae of predatory Tropisternus sp . for use in laboratory bioassays against larvae of Anopheles quadrimaculatus and Psorophora columbiae is described .
On 10 occasions , an average of 5 . 2 traps was used per evening , resulting in 52 trap-nights that accumulated 106 . 7 h of trapping time , or an average of 10 . 6 h per trap .
Use of 2 heavy-duty alkaline D-sized batteries and appropriate in-circuit resistance effectively increased bulb life and trap operating time , ranging from 22 to 36 h .
During both seasons , approximately 3 wk after permanent flooding of large rice fields was the most productive period in which to capture larvae of Tropisternus sp .
Live trapping worked well and provided numerous larvae of Tropisternus sp . for use in laboratory predation bioassays with An . quadrimaculatus and Ps . columbiae larvae .
Six hundred fifteen 3rd-stage larvae of Tropisternus sp . and 740 adult Tropisternus lateralis were captured in aquatic light traps in 1999 and 2000 .
Of traps containing larval Tropisternus sp . and adult T lateralis , average numbers of 15 . 3 and 19 . 4 were captured per trap , respectively .
Among all traps , the largest nightly captures of larval Tropisternus sp . and adult T lateralis consisted of 263 and 404 specimens , respectively .
The largest single trap captures for larval Tropisternus sp . and adult T lateralis were 94 and 184 , respectively .
Additionally , 478 rice water weevils ( Lissorhoptrus oryzophilus ) also were captured .
Rice water weevils averaged 36 . 7 per trap , with the largest single trap capture of 102 weevils on an evening where 287 weevils were captured among all traps .
Other predatory insect species were captured infrequently , consisting primarily of 3rd-stage larvae of Hydrophilus triangularis and adult belostomatids , dytiscids , and notonectids .
Predatory larvae of H triangularis may have been attracted to the traps by the presence of larval Tropisternus sp .
Larval Tropisternus sp . may have been attracted by the light source and prey items that entered the trap , such as chironomid larvae . | Matching Sentences:
[ Sen. 1, subscore: 2.00 ]: Construction of an aquatic light trap developed for the live capture of 3rd-stage larvae of predatory Tropisternus sp . for use in laboratory bioassays against larvae of Anopheles quadrimaculatus and Psorophora columbiae is described .
[ Sen. 4, subscore: 2.00 ]: During both seasons , approximately 3 wk after permanent flooding of large rice fields was the most productive period in which to capture larvae of Tropisternus sp .
[ Sen. 5, subscore: 2.00 ]: Live trapping worked well and provided numerous larvae of Tropisternus sp . for use in laboratory predation bioassays with An . quadrimaculatus and Ps . columbiae larvae .
[ Sen. 8, subscore: 2.00 ]: Among all traps , the largest nightly captures of larval Tropisternus sp . and adult T lateralis consisted of 263 and 404 specimens , respectively .
[ Sen. 9, subscore: 2.00 ]: The largest single trap captures for larval Tropisternus sp . and adult T lateralis were 94 and 184 , respectively .
[ Sen. 13, subscore: 2.00 ]: Predatory larvae of H triangularis may have been attracted to the traps by the presence of larval Tropisternus sp .
[ Sen. 14, subscore: 2.00 ]: Larval Tropisternus sp . may have been attracted by the light source and prey items that entered the trap , such as chironomid larvae .
[ Sen. 6, subscore: 1.00 ]: Six hundred fifteen 3rd-stage larvae of Tropisternus sp . and 740 adult Tropisternus lateralis were captured in aquatic light traps in 1999 and 2000 .
[ Sen. 7, subscore: 1.00 ]: Of traps containing larval Tropisternus sp . and adult T lateralis , average numbers of 15 . 3 and 19 . 4 were captured per trap , respectively .
[ Sen. 11, subscore: 1.00 ]: Rice water weevils averaged 36 . 7 per trap , with the largest single trap capture of 102 weevils on an evening where 287 weevils were captured among all traps .
[ Sen. 12, subscore: 1.00 ]: Other predatory insect species were captured infrequently , consisting primarily of 3rd-stage larvae of Hydrophilus triangularis and adult belostomatids , dytiscids , and notonectids .
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Score: 17.00 |
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| Title: Efficacy of VectoLex WDG against Anopheles quadrimaculatus and Psorophora columbiae larvae in Arkansas and Mississippi rice .
| | Author: Dennett JA Meek CL Meisch MV .
| | Journal: J Am . Mosq . Control Assoc .
Citation: V : 17 ( 4 ) P : 231-7 Year: 2001 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub11804459 Accession (PMID): 11804459 | | Abstract: In 1999 , an aerial application of VectoLex WDG ( water-dispersible granules ) at 1 . 68 and 0 . 56 kg/ha , applied against sentinel 3rd-stage larvae of Psorophora columbiae installed in 0 . 42-ha rice plots 48 h after treatment , provided no control at 72 and 96 h after treatment .
Less than 10% reduction was obtained at both rates 8 and 9 days after treatment against larvae of Ps . columbiae installed at 7 days after treatment .
In a later test , VectoLex WDG manually applied at 5 . 04 and 1 . 68 kg/ha to small rice plots containing sentinel 3rd-stage larvae of Ps . columbiae and Anopheles quadrimaculatus obtained 90 and 97% control of Ps . columbiae at both rates , respectively , 24 h after treatment .
A 2nd installation of Ps . columbiae at 24 h after treatment resulted in 7% and no control at both rates , respectively , even in the presence of larval carcasses from the 1st installation .
VectoLex WDG was not effective against Ps . columbiae after 24 h atter treatment at either rate .
Poor control was obtained at both rates against An . quadrimaculatus 24 h and 48 h after treatment for both installations .
Two types of commercial rice fields containing native populations of larvae of An . quadrimaculatus were used for field tests in Cleveland , MS .
In 1999 , VectoLex WDG , aerially applied at 1 . 68 and 0 . 56 kg/ha to 0 . 2-ha plots in a contoured rice field , produced 81 and 85% reductions in early ( neonate and 1st and 2nd-stage ) larvae and 94 and 76% reductions in late ( 3rd and 4th-stage ) larvae 2 days after treatment , respectively .
At 2 days after treatment , means for all 4 developmental groupings ( early larvae , late larvae , pupae , and combined stages ) were significantly higher in untreated plots .
Both VectoLex WDG rates did not differ significantly from one another .
At 8 days after treatment , untreated plots contained significantly greater mean numbers of early larvae , late larvae , and combined stages , whereas both VectoLex WDG treatments were not significantly different .
In 2000 , VectoLex WDG applied at 1 . 68 kg/ha to two 0 . 40-ha plots in a precision-leveled field yielded 59 and 100% reductions of early and late larvae , respectively , 2 days after treatment .
Reduction of late larvae remained 100% at 8 days after treatment .
The numbers of late larvae , pupae , and combined stages were significantly greater in the untreated plot 2 days after treatment .
At 8 days after treatment , numbers of early larvae and combined stages were significantly higher in the VectoLex WDG plot , whereas numbers of late larvae were significantly higher in the untreated plot .
The differences in susceptibility of Ps . columbiae and An . quadrimaculatus to VectoLex WDG could be attributed to species differences in larval feeding behavior , body positioning in the water column , and developmental time .
In tests in Arkansas , Ps . columbiae were controlled more quickly , usually within 24 h of exposure , whereas the percent reduction for An . quadrimaculatus in both tests in Cleveland , MS , suggests that control of this species within the region tested required from 48 h up to 8 days of exposure . | Matching Sentences:
[ Sen. 8, subscore: 2.00 ]: In 1999 , VectoLex WDG , aerially applied at 1 . 68 and 0 . 56 kg/ha to 0 . 2-ha plots in a contoured rice field , produced 81 and 85% reductions in early ( neonate and 1st and 2nd-stage ) larvae and 94 and 76% reductions in late ( 3rd and 4th-stage ) larvae 2 days after treatment , respectively .
[ Sen. 9, subscore: 2.00 ]: At 2 days after treatment , means for all 4 developmental groupings ( early larvae , late larvae , pupae , and combined stages ) were significantly higher in untreated plots .
[ Sen. 11, subscore: 2.00 ]: At 8 days after treatment , untreated plots contained significantly greater mean numbers of early larvae , late larvae , and combined stages , whereas both VectoLex WDG treatments were not significantly different .
[ Sen. 15, subscore: 2.00 ]: At 8 days after treatment , numbers of early larvae and combined stages were significantly higher in the VectoLex WDG plot , whereas numbers of late larvae were significantly higher in the untreated plot .
[ Sen. 1, subscore: 1.00 ]: In 1999 , an aerial application of VectoLex WDG ( water-dispersible granules ) at 1 . 68 and 0 . 56 kg/ha , applied against sentinel 3rd-stage larvae of Psorophora columbiae installed in 0 . 42-ha rice plots 48 h after treatment , provided no control at 72 and 96 h after treatment .
[ Sen. 2, subscore: 1.00 ]: Less than 10% reduction was obtained at both rates 8 and 9 days after treatment against larvae of Ps . columbiae installed at 7 days after treatment .
[ Sen. 3, subscore: 1.00 ]: In a later test , VectoLex WDG manually applied at 5 . 04 and 1 . 68 kg/ha to small rice plots containing sentinel 3rd-stage larvae of Ps . columbiae and Anopheles quadrimaculatus obtained 90 and 97% control of Ps . columbiae at both rates , respectively , 24 h after treatment .
[ Sen. 4, subscore: 1.00 ]: A 2nd installation of Ps . columbiae at 24 h after treatment resulted in 7% and no control at both rates , respectively , even in the presence of larval carcasses from the 1st installation .
[ Sen. 7, subscore: 1.00 ]: Two types of commercial rice fields containing native populations of larvae of An . quadrimaculatus were used for field tests in Cleveland , MS .
[ Sen. 12, subscore: 1.00 ]: In 2000 , VectoLex WDG applied at 1 . 68 kg/ha to two 0 . 40-ha plots in a precision-leveled field yielded 59 and 100% reductions of early and late larvae , respectively , 2 days after treatment .
[ Sen. 13, subscore: 1.00 ]: Reduction of late larvae remained 100% at 8 days after treatment .
[ Sen. 14, subscore: 1.00 ]: The numbers of late larvae , pupae , and combined stages were significantly greater in the untreated plot 2 days after treatment .
[ Sen. 16, subscore: 1.00 ]: The differences in susceptibility of Ps . columbiae and An . quadrimaculatus to VectoLex WDG could be attributed to species differences in larval feeding behavior , body positioning in the water column , and developmental time .
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Score: 11.00 |
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| Title: Characterization of rice field mosquito habitats in Sharkia Governorate , Egypt .
| | Author: Kenawy MA Rashed SS Teleb SS .
| | Journal: Citation: V : 28 ( 2 ) P : 449-59 Year: 1998 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub9707674 Accession (PMID): 9707674 | | Abstract: The characteristics of the breeding water , interspecific association and seasonal abundance of 3 mosquito species within rice fields were examined in 6 districts .
Larvae of Cx . antennatus were dominant ( 83 . 71% collected larvae ) , of An pharoensis were common ( 12 . 29% ) and of Cx perexiguus were uncommon ( 4 . 0 = . 0% ) .
Breeding water has pH of 6-8 , salinity of 0 . 05-0 . 35 gm Cl/L and temperature of 21-29 degrees C Although the relation of larval density ( for each species ) was positive with pH and negative with salinity and temperature however , no interaction ( regression analysis ) was existed among the variables ( R = 0 . 26-0 . 40 , P > 0 . 05 ) .
Significant and complete associations ( CAB = 1 . 0 , P < 0 . 01 ) were detected for Cx . antennatus with other species .
During rice growing period ( June to October ) , Cx perexiguus larvae were quite short lasting ( June to August ) .
Larval abundance varied monthly in relation to the plant growth stage .
No larvae of any species were collected in short plant ( < 20 cm , beginning of June ) or in very long ones ( 130 cm in October ) .
Higher numbers of larvae were often associated with the moderate plant growth ( 50-80 cm ) with a peak in plants of 70 cm height in August ( 161 . 50 larvae/10 net dips for the 3 species ) .
The highest larval density for Cx antennatus ( 132 . 50 larvae ) and An pharoensis ( 22 . 25 larvae ) were during August ( 70 cm plant ) and for Cx . perexiguus ( 7 . 67 larvae ) was in July ( 60 cm plant ) .
So , rice fields are potential habitats for these disease vectors .
The plant height and irrigation scheme are major factors affecting the abundance of these species . | Matching Sentences:
[ Sen. 9, subscore: 4.00 ]: The highest larval density for Cx antennatus ( 132 . 50 larvae ) and An pharoensis ( 22 . 25 larvae ) were during August ( 70 cm plant ) and for Cx . perexiguus ( 7 . 67 larvae ) was in July ( 60 cm plant ) .
[ Sen. 2, subscore: 2.00 ]: Larvae of Cx . antennatus were dominant ( 83 . 71% collected larvae ) , of An pharoensis were common ( 12 . 29% ) and of Cx perexiguus were uncommon ( 4 . 0 = . 0% ) .
[ Sen. 3, subscore: 1.00 ]: Breeding water has pH of 6-8 , salinity of 0 . 05-0 . 35 gm Cl/L and temperature of 21-29 degrees C Although the relation of larval density ( for each species ) was positive with pH and negative with salinity and temperature however , no interaction ( regression analysis ) was existed among the variables ( R = 0 . 26-0 . 40 , P > 0 . 05 ) .
[ Sen. 5, subscore: 1.00 ]: During rice growing period ( June to October ) , Cx perexiguus larvae were quite short lasting ( June to August ) .
[ Sen. 6, subscore: 1.00 ]: Larval abundance varied monthly in relation to the plant growth stage .
[ Sen. 7, subscore: 1.00 ]: No larvae of any species were collected in short plant ( < 20 cm , beginning of June ) or in very long ones ( 130 cm in October ) .
[ Sen. 8, subscore: 1.00 ]: Higher numbers of larvae were often associated with the moderate plant growth ( 50-80 cm ) with a peak in plants of 70 cm height in August ( 161 . 50 larvae/10 net dips for the 3 species ) .
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Score: 10.00 |
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| Title: Diapause development and acclimation regulating enzymes associated with glycerol synthesis in the Shonai ecotype of the rice stem borer larva , Chilo suppressalis walker .
| | Author: Li YP Goto M Ding L Tsumuki H | | Journal: Citation: V : 48 ( 3 ) P : 303-310 Year: 2002 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub12770104 Accession (PMID): 12770104 | | Abstract: Overwintering larvae of the Shonai ecotype of the rice stem borer , Chilo suppressalis , enter diapause in early September and terminate diapause at the end of October .
Cold acclimation at 0 degrees C did not influence glycerol , trehalose or glycogen content in larvae collected on 22 September .
Acclimation at 0 degrees C increased the glycerol content and reduced the glycogen content significantly in larvae collected on 2 October and 22 November compared with acclimation at 15 degrees C These results indicate that overwintering larvae at different phases of diapause development respond differently to the low temperature stimulus for glycerol synthesis .
Thus , we evaluated the metabolic rearrangements associated with glycerol synthesis during diapause development and after temperature acclimation .
Larvae collected on 2 October were acclimated at 15 degrees C for 15 and 60 days .
Some of those acclimated at 15 degrees C were then moved to 0 degrees C for 15 days .
The larvae acclimated at 15 degrees C for 15 days were in deep diapause and accumulated little glycerol , while larvae acclimated at 15 degrees C for 60 days were nearly ready to emerge from diapause and accumulated glycerol at 155 . 5 &mgr ; mol/g .
When larvae acclimated to 15 degrees C for 15 days were transferred to 0 degrees C , glycerol accumulation was stimulated to the same extent ( ca 140 &mgr ; mol/g ) as it was in larvae that were acclimated to 15 degrees C for 60 days and then transferred to 0 degrees C These results indicate that low temperature has a cumulative effect on glycerol production in larvae at different phases of diapause development .
Glycerol accumulation was accomplished by activation of glycogen phosphorylase and inhibition of fructose-1 , 6-bisphosphatase , and activation of enzymes associated with glycerol synthesis , mainly glyceraldehyde-3-phosphatase and polyol dehydrogenase with glyceraldehyde activity .
| Matching Sentences:
[ Sen. 8, subscore: 3.00 ]: When larvae acclimated to 15 degrees C for 15 days were transferred to 0 degrees C , glycerol accumulation was stimulated to the same extent ( ca 140 &mgr ; mol/g ) as it was in larvae that were acclimated to 15 degrees C for 60 days and then transferred to 0 degrees C These results indicate that low temperature has a cumulative effect on glycerol production in larvae at different phases of diapause development .
[ Sen. 3, subscore: 2.00 ]: Acclimation at 0 degrees C increased the glycerol content and reduced the glycogen content significantly in larvae collected on 2 October and 22 November compared with acclimation at 15 degrees C These results indicate that overwintering larvae at different phases of diapause development respond differently to the low temperature stimulus for glycerol synthesis .
[ Sen. 7, subscore: 2.00 ]: The larvae acclimated at 15 degrees C for 15 days were in deep diapause and accumulated little glycerol , while larvae acclimated at 15 degrees C for 60 days were nearly ready to emerge from diapause and accumulated glycerol at 155 . 5 &mgr ; mol/g .
[ Sen. 1, subscore: 1.00 ]: Overwintering larvae of the Shonai ecotype of the rice stem borer , Chilo suppressalis , enter diapause in early September and terminate diapause at the end of October .
[ Sen. 2, subscore: 1.00 ]: Cold acclimation at 0 degrees C did not influence glycerol , trehalose or glycogen content in larvae collected on 22 September .
[ Sen. 5, subscore: 1.00 ]: Larvae collected on 2 October were acclimated at 15 degrees C for 15 and 60 days .
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Score: 10.00 |
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| Title: Factors affecting the toxicity of Bacillus thuringiensis var . israelensis and Bacillus sphaericus to fourth instar larvae of Chironomus tepperi ( Diptera : Chironomidae ) .
| | Author: Stevens MM Akhurst RJ Clifton MA Hughes PA .
| | Journal: J Invertebr . Pathol . Citation: V : 86 ( 3 ) P : 104-10 Year: 2004 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub15261774 Accession (PMID): 15261774 | | Abstract: Laboratory bioassays ( 48h duration , 25+/-1 degrees C ) were used to determine the toxicity of Bacillus thuringiensis var . israelensis ( Bt . i . ) and Bacillus sphaericus to fourth instar larvae of Chironomus tepperi , a major pest of rice in southern Australia .
Bioassays were conducted using different combinations of larval ages and densities to determine if these factors affected toxicity .
The effects of temperature and substrate type on Bt . i . toxicity were also investigated .
Tests were conducted using a commercial Bt . i . formulation ( VectoBac WDG , 3000ITU/mg ) , a spore/crystal mixture derived from the VectoBac WDG strain , and VectoLex WDG , a commercial B sphaericus formulation ( 650ITU/mg ) .
VectoBac WDG was highly toxic to fourth instar C tepperi in bioassays using a sand substrate ( LC ( 50 ) 0 . 46mg/L , older larvae ) ; younger fourth instar larvae were more susceptible ( LC ( 50 ) 0 . 20mg/L ) .
Increasing larval densities ( from 10 to 30 per bioassay cup ) increased LC ( 50 ) values for both age groups , significantly so in the case of older larvae ( higher density LC ( 50 ) 0 . 80mg/L ) .
Use of a soil substrate increased the LC ( 50 ) value ( older larvae , 10 per cup ) to 0 . 99mg/L Similar differences in toxicity relative to larval age and substrate type were found in bioassays using the Bt . i . spore/crystal mixture .
VectoBac WDG and the spore/crystal mixture both showed similar ( approximately 6-fold ) declines in activity between 30 and 17 . 5 degrees C At lower temperatures ( between 17 . 5 and 15 degrees C ) , activity of the spore/crystal mixture declined much more rapidly than that of VectoBac WDG .
VectoLex WDG showed very low toxicity to C tepperi larvae , and the overall impact of larval age and density was relatively minor ( LC ( 50 ) values 1062-1340mg/L ) .
Autoclaving VectoLex WDG did not substantially reduce its toxicity ( LC ( 50 ) 1426mg/L ) , suggesting that formulation additives ( ie , surfactants and other adjuvants ) are responsible for much of the toxicity occurring at the high product concentrations required to cause C tepperi mortality .
Whilst VectoLex WDG was ineffective against C tepperi , VectoBac WDG has the potential to provide selective control of this rice pest at economically viable application rates .
| Matching Sentences:
[ Sen. 5, subscore: 2.00 ]: VectoBac WDG was highly toxic to fourth instar C tepperi in bioassays using a sand substrate ( LC ( 50 ) 0 . 46mg/L , older larvae ) ; younger fourth instar larvae were more susceptible ( LC ( 50 ) 0 . 20mg/L ) .
[ Sen. 6, subscore: 2.00 ]: Increasing larval densities ( from 10 to 30 per bioassay cup ) increased LC ( 50 ) values for both age groups , significantly so in the case of older larvae ( higher density LC ( 50 ) 0 . 80mg/L ) .
[ Sen. 7, subscore: 2.00 ]: Use of a soil substrate increased the LC ( 50 ) value ( older larvae , 10 per cup ) to 0 . 99mg/L Similar differences in toxicity relative to larval age and substrate type were found in bioassays using the Bt . i . spore/crystal mixture .
[ Sen. 9, subscore: 2.00 ]: VectoLex WDG showed very low toxicity to C tepperi larvae , and the overall impact of larval age and density was relatively minor ( LC ( 50 ) values 1062-1340mg/L ) .
[ Sen. 1, subscore: 1.00 ]: Laboratory bioassays ( 48h duration , 25+/-1 degrees C ) were used to determine the toxicity of Bacillus thuringiensis var . israelensis ( Bt . i . ) and Bacillus sphaericus to fourth instar larvae of Chironomus tepperi , a major pest of rice in southern Australia .
[ Sen. 2, subscore: 1.00 ]: Bioassays were conducted using different combinations of larval ages and densities to determine if these factors affected toxicity .
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