We used regression analysis to quantify yield variations in cowpea due to major insect pests, i.e... more We used regression analysis to quantify yield variations in cowpea due to major insect pests, i.e., aphids (Aphis craccivora Koch), thrips (Megarulothrips sjostedti Trybom), Maruca pod borer (Maruca vitrata Fabricius) and a complex of pod-sucking bugs. Variability in pest infestation was created by growing Ebelat (an erect cowpea cultivar) in two locations over three seasons and under different insecticide spray
ABSTRACT Field studies were conducted during 2003 and 2004 for three consecutive growing seasons.... more ABSTRACT Field studies were conducted during 2003 and 2004 for three consecutive growing seasons. The treatments were (1) market crop wastes (MCW) compost incorporated in the soil, (2) un-composted MCW incorporated in the soil, (3) un-composted MCW applied as a surface mulch, (4) a conventional chemical fertilizer (NPK) incorporated in the soil, and (5) the untreated control. Response variables recorded included plant height and width, leaf area, tissue nitrogen content, nodulation; occurrence of Aphis fabae, Maruca vitrata and the associated natural enemies; and grain yield. Results indicated that significant differences in plant attributes and yield were only detected in the second and subsequent season of the crop or when weather conditions were stressful. For the insect pests, it was only A. fabae infestation that varied among treatments with MCW amended plants sustaining higher infestations than NPK and the untreated control, a trend that held for all the seasons. Natural enemy occurrence followed the trend of A. fabae infestation. After the first and subsequent harvests, more P, K, Ca, and Mg were extracted from the soil from MCW plots than NPK plots. The study indicated that yields accruing from MCW amended plots were comparable and sometimes even higher than those from NPK despite the higher A. fabae infestation of the former.
ABSTRACT The damage caused by the bean fly (Ophiomyia sp.), which is the major insect pest of bea... more ABSTRACT The damage caused by the bean fly (Ophiomyia sp.), which is the major insect pest of beans in Uganda, is more serious in poor soils and under drought conditions. There is, however, limited information on cause and effect. This study investigated the relationship between fertiliser and the influence of moisture conservation through mulching on bean fly infestation. Fertiliser application significantly increased bean fly oviposition per leaf, number of pupae per plant and plant mortality. Mulching also significantly reduced bean fly pupae density and bean plant mortality. Mulching increased soil moisture content and there was a significant negative relationship between soil moisture content and bean fly pupae density. The influence of fertiliser and mulching on bean fly damage is discussed based on nitrogen and water relationships in plant growth.
We used regression analysis to quantify yield variations in cowpea due to major insect pests, i.e... more We used regression analysis to quantify yield variations in cowpea due to major insect pests, i.e., aphids (Aphis craccivora Koch), thrips (Megarulothrips sjostedti Trybom), Maruca pod borer (Maruca vitrata Fabricius) and a complex of pod-sucking bugs. Variability in pest infestation was created by growing Ebelat (an erect cowpea cultivar) in two locations over three seasons and under different insecticide spray
ABSTRACT Field studies were conducted during 2003 and 2004 for three consecutive growing seasons.... more ABSTRACT Field studies were conducted during 2003 and 2004 for three consecutive growing seasons. The treatments were (1) market crop wastes (MCW) compost incorporated in the soil, (2) un-composted MCW incorporated in the soil, (3) un-composted MCW applied as a surface mulch, (4) a conventional chemical fertilizer (NPK) incorporated in the soil, and (5) the untreated control. Response variables recorded included plant height and width, leaf area, tissue nitrogen content, nodulation; occurrence of Aphis fabae, Maruca vitrata and the associated natural enemies; and grain yield. Results indicated that significant differences in plant attributes and yield were only detected in the second and subsequent season of the crop or when weather conditions were stressful. For the insect pests, it was only A. fabae infestation that varied among treatments with MCW amended plants sustaining higher infestations than NPK and the untreated control, a trend that held for all the seasons. Natural enemy occurrence followed the trend of A. fabae infestation. After the first and subsequent harvests, more P, K, Ca, and Mg were extracted from the soil from MCW plots than NPK plots. The study indicated that yields accruing from MCW amended plots were comparable and sometimes even higher than those from NPK despite the higher A. fabae infestation of the former.
ABSTRACT The damage caused by the bean fly (Ophiomyia sp.), which is the major insect pest of bea... more ABSTRACT The damage caused by the bean fly (Ophiomyia sp.), which is the major insect pest of beans in Uganda, is more serious in poor soils and under drought conditions. There is, however, limited information on cause and effect. This study investigated the relationship between fertiliser and the influence of moisture conservation through mulching on bean fly infestation. Fertiliser application significantly increased bean fly oviposition per leaf, number of pupae per plant and plant mortality. Mulching also significantly reduced bean fly pupae density and bean plant mortality. Mulching increased soil moisture content and there was a significant negative relationship between soil moisture content and bean fly pupae density. The influence of fertiliser and mulching on bean fly damage is discussed based on nitrogen and water relationships in plant growth.
Uploads
Papers by S. Kyamanywa