22182619
not annotated - annotated - LINNAEUS only
Dispersion Models and Sampling of Cacao Mirid Bug Sahlbergella singularis (Hemiptera: Miridae) on Theobroma Cacao in Southern Cameroon.
The spatio-temporal distribution of Sahlbergella singularis Haglung, a major pest of cacao trees (Theobroma cacao) (Malvaceae), was studied for 2 yr in traditional cacao forest gardens in the humid forest area of southern Cameroon. The first objective was to analyze the dispersion of this insect on cacao trees. The second objective was to develop sampling plans based on fixed levels of precision for estimating S. singularis populations. The following models were used to analyze the data: Taylor's power law, Iwao's patchiness regression, the Nachman model, and the negative binomial distribution. Our results document that Taylor's power law was a better fit for the data than the Iwao and Nachman models. Taylor's b and Iwao's Beta were both significantly >1, indicating that S. singularis aggregated on specific trees. This result was further supported by the calculated common k of 1.75444. Iwao's alpha was significantly <0, indicating that the basic distribution component of S. singularis was the individual insect. Comparison of negative binomial (NBD) and Nachman models indicated that the NBD model was appropriate for studying S. singularis distribution. Optimal sample sizes for fixed precision levels of 0.10, 0.15, and 0.25 were estimated with Taylor's regression coefficients. Required sample sizes increased dramatically with increasing levels of precision. This is the first study on S. singularis dispersion in cacao plantations. Sampling plans, presented here, should be a tool for research on population dynamics and pest management decisions of mirid bugs on cacao.
Ann file
T1 Species 98 113 Theobroma Cacao
N1 Reference T1 Taxonomy:3641
T2 Species 223 228 cacao
N2 Reference T2 Taxonomy:3641
T3 Species 236 251 Theobroma cacao
N3 Reference T3 Taxonomy:3641
T4 Species 302 307 cacao
N4 Reference T4 Taxonomy:3641
T5 Species 438 443 cacao
N5 Reference T5 Taxonomy:3641
T6 Species 1577 1582 cacao
N6 Reference T6 Taxonomy:3641
T7 Species 1728 1733 cacao
N7 Reference T7 Taxonomy:3641
T8 Species 50 73 Sahlbergella singularis
N8 Reference T8 Taxonomy:1188055 Sahlbergella singularis
T9 Species 174 197 Sahlbergella singularis
N9 Reference T9 Taxonomy:1188055 Sahlbergella singularis
T10 Species 552 565 S. singularis
N10 Reference T10 Taxonomy:1188055 Sahlbergella singularis
T11 Species 1130 1143 S. singularis
N11 Reference T11 Taxonomy:1188055 Sahlbergella singularis
T12 Species 923 936 S. singularis
N12 Reference T12 Taxonomy:1188055 Sahlbergella singularis
T13 Species 1286 1299 S. singularis
N13 Reference T13 Taxonomy:1188055 Sahlbergella singularis
T14 Species 1549 1562 S. singularis
N14 Reference T14 Taxonomy:1188055 Sahlbergella singularis