Author
![]() |
Gouge, Dawn |
![]() |
SMITH, KIRK - BIOSYS, INC |
![]() |
PAYNE, CHARLIE - TEXAS A&M, EL PASO TX |
![]() |
Lee, Linda |
![]() |
Van Berkum, Jamie |
![]() |
ORTEGO, DANIEL - TEXAS A&M EL PASO TX |
![]() |
Henneberry, Thomas |
Submitted to: University of Arizona Agricultural Experiment Station
Publication Type: Proceedings Publication Acceptance Date: 6/1/1997 Publication Date: N/A Citation: N/A Interpretive Summary: At pre-sowing irrigation (mid-March), cotton fields were treated with two insect parasitic nematode species; Steinernema riobravis and S. carpocapsae for control of diapausing Pink bollworm larvae. Nematodes were applied with a spray rig, fixed winged aircraft, or in furrow irrigation via a constant flow, battery box. Fields were irrigated after ground application, prior to oaerial spraying and during furrow application. All application methods resulted in uniform distribution of nematodes over the treated fields. Larval mortality ranged from 53.26-79.14%. At pin-head square Frustrate PBW pheromone bands (Thermo trilogy Corp.) were applied at 100 bands per acre placement rate (16 g a.i./acre), giving a target release of 115 mg gossyplure/acre/day. Pink bollworm mating disruption was monitored. Delta 2 traps showed significantly larger numbers of moths recovered form untreated zones. Mating table data revealed significantly higher mating activity occurring in untreated fields. Green boll samples also indicated significantly higher infestation levels existing in untreated zones. At harvest (November), seed cotton yields were weighed using trailer scales. Higher yields were recovered from pheromone (1,864 lb/acre), and pheromone + nematode fields (1,712 lb/acre), than control fields (1,450 lb/acre). Technical Abstract: At presowing irrigation, cotton fields were treated with two entomopathogenic nematode species for control of dispausing pink bollworm larvae. Pima S-6 cotton fields were treated at a rate of one billion nematodes/acre. Application methods resulted in uniform distribution of nematodes over the treated fields. No significant differences in larval mortality between nematode species or application method could be determined. Larval mortality ranged from 53.26-79.14%. Both nematode species could be recovered 50 days post application. At pin-head square Frustrate(TM) PBW pheromone bands (biosys, Inc.) were applied at 100 bands per acre placement rate (16 g a.i./acre), giving a target release of 115 mg gossyplure/acre/day. Capillary gas chromatography was used to analyze bands throughout the growing season. A uniform release profile indicated sufficient release of pheromone for 144 days after placement. |