Chemical control of capsids and other insect pests in cocoa rehabilitation
For the rehabilitation of mature stands substantially degraded by capsids, extended spray trials were undertaken with gamma-BHC (Gammalin, 4 and 3 oz a.i./acre = 280 and 210 g/ha), arprocarb, (Baygon, 3 and 2 oz a.i./acre = 210 and 140 g/ha), DDT (Arkotine, 30 oz a.i./acre = 2100 g/ha), arprocarb-DDT mixture (2 plus 10 oz a.i./acre = 140 plus 700 g/ha) and fenitrothion (Agrothion, 10 oz a.i./acre = 700 g/ha). The more successful treatments, gamma-BHC and arprocarb, gave substantial canopy recovery and increased pod setting by a factor of over 2 compared with control plots. Monocrotophos (Azodrin) applied at 0.3 per cent a.i. by mistblower arrested severe degradation due to capsids and leaf-hoppers and resulted in particularly rapid canopy restoration, i.e. in a more than two-fold increase of foliage density after three sprays. However, because of the relatively high toxicity of monocrotophos, mistblowing is recommended only in special situations. Protection of young replants on cleared capsid pockets or sites adjacent to heavily infested mature cocoa was given by stem painting with systemic insecticides, Monocrotophos at 0.86 and 0.43 g a.i. per tree applied monthly to three-year old stands gave virtually complete control of both capsid species D. theobroma and S. singularis in addition to minor pests including aphids, T. aurantii, psyllids, T. tessmanni and thrips, S. rubrocinctus, with also some degree of control of leaf feeding lepidoptera; yield was increased by a factor of 3.5 compared with no treatment. On seedlings good control was given of leaf feeding beetles, A. umbrosus
Main Authors: | , , , |
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Format: | biblioteca |
Published: |
Tafo (Ghana)
1971
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Subjects: | THEOBROMA CACAO, REHABILITACION DE TIERRAS, SAHLBERGELLA SINGULARIS, DISTANTIELLA THEOBROMAE, TOXOPTERA AURANTII, TYORA TESSMANNI, SELENOTHRIPS RUBROCINCTUS, ADORETUS UMBROSUS, INSECTOS DAÑINOS, CONTROL QUIMICO, CAPSIDOS, GHANA, |
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Summary: | For the rehabilitation of mature stands substantially degraded by capsids, extended spray trials were undertaken with gamma-BHC (Gammalin, 4 and 3 oz a.i./acre = 280 and 210 g/ha), arprocarb, (Baygon, 3 and 2 oz a.i./acre = 210 and 140 g/ha), DDT (Arkotine, 30 oz a.i./acre = 2100 g/ha), arprocarb-DDT mixture (2 plus 10 oz a.i./acre = 140 plus 700 g/ha) and fenitrothion (Agrothion, 10 oz a.i./acre = 700 g/ha). The more successful treatments, gamma-BHC and arprocarb, gave substantial canopy recovery and increased pod setting by a factor of over 2 compared with control plots. Monocrotophos (Azodrin) applied at 0.3 per cent a.i. by mistblower arrested severe degradation due to capsids and leaf-hoppers and resulted in particularly rapid canopy restoration, i.e. in a more than two-fold increase of foliage density after three sprays. However, because of the relatively high toxicity of monocrotophos, mistblowing is recommended only in special situations. Protection of young replants on cleared capsid pockets or sites adjacent to heavily infested mature cocoa was given by stem painting with systemic insecticides, Monocrotophos at 0.86 and 0.43 g a.i. per tree applied monthly to three-year old stands gave virtually complete control of both capsid species D. theobroma and S. singularis in addition to minor pests including aphids, T. aurantii, psyllids, T. tessmanni and thrips, S. rubrocinctus, with also some degree of control of leaf feeding lepidoptera; yield was increased by a factor of 3.5 compared with no treatment. On seedlings good control was given of leaf feeding beetles, A. umbrosus |
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