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Plant Sciences

Department of Entomology: Faculty Publications

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Oryza sativa L.

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Articles 1 - 4 of 4

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Response Of Lowland Rice Plants To Simulated Insect Defoliation In West Africa, I. O. Oyediran, E. A. Heinrichs Jan 2002

Response Of Lowland Rice Plants To Simulated Insect Defoliation In West Africa, I. O. Oyediran, E. A. Heinrichs

Department of Entomology: Faculty Publications

Field experiments were conducted to investigate the impact of simulated insect-caused defoliation on irrigated rice. Defoliation levels tested were 0% (control), 25% defoliation at 21 days after transplanting (dat), 25% defoliation at 41 dat, 25% defoliation at 21 and 42 dat, 50% defoliation at 21 dat, 50% defoliation at 42 dat, 75% defoliation at 21 dat, 75% defoliation at 42 dat, 75% defoliation at 21 and 42 dat, 100% defoliation at 21 dat, and 100% defoliation at 21 and 42 dat. Tiller height, total number of tillers, percent panicle-bearing tillers, weight of 100 grains, and grain yields were recorded. The …


Arthropod Populations And Rice Yields In Direct-Seeded And Transplanted Lowland Rice In West Africa, I. O. Oyediran, E. A. Heinrichs Jan 2001

Arthropod Populations And Rice Yields In Direct-Seeded And Transplanted Lowland Rice In West Africa, I. O. Oyediran, E. A. Heinrichs

Department of Entomology: Faculty Publications

Two methods for planting rice in irrigated lowland were evaluated during the wet seasons of 1994 and 1995 to determine their effect on rice arthropod numbers, insect-caused rice plant damage, and rice grain yield. The six treatments tested were: hand transplanting of seedlings at spacings of 14 cm × 14 cm, 20 cm × 20 cm, and 30 cm × 30 cm; and direct-seeding of rice at 60 kg seeds ha–1, 90 kg seeds ha–1, and 120 kg seeds ha–1. The most abundant arthropods in the study were the diopsid flies, Diopsis longicornis Maquart …


Strepsipteran Parasitism Of White Leafhoppers, Cofana Spp. (Hemiptera: Cicadellidae) In Lowland Rice In Côte D’Ivoire, I. O. Oyediran, A. Ndongidila, E. A. Heinrichs Jan 2000

Strepsipteran Parasitism Of White Leafhoppers, Cofana Spp. (Hemiptera: Cicadellidae) In Lowland Rice In Côte D’Ivoire, I. O. Oyediran, A. Ndongidila, E. A. Heinrichs

Department of Entomology: Faculty Publications

Three tests were conducted over a 2-year period in lowland irrigated rice fields on the WARDA Research Station at Bouaké, Côte d’Ivoire, to obtain information on the strepsipteran parasitism of white leafhoppers, Cofana spectra and C. unimaculata. Rice cultivars were sampled with a sweep net to collect leafhoppers for determination of the relative abundance of the two leafhopper species and the effect of rice cultivar and rice crop age on the leafhopper populations and percent strepsipteran parasitism. Dissections of the leafhoppers were made to determine the relative number of the various parasitic stages in the leafhoppers. Cofana unimaculata populations …


Seasonal Occurrence Of Rice Yellow Mottle Virus In Lowland Rice In Côte D’Ivoire, E. A. Heinrichs, A. A. Sy, S. K. Akator, I. Oyediran Jan 1997

Seasonal Occurrence Of Rice Yellow Mottle Virus In Lowland Rice In Côte D’Ivoire, E. A. Heinrichs, A. A. Sy, S. K. Akator, I. Oyediran

Department of Entomology: Faculty Publications

Monthly plantings of the rice variety Bouaké 189 were made under lowland irrigated conditions, to obtain information on the phenological and seasonal occurrence of pests and diseases on the West African Rice Development Association (WARDA) research farm near Bouaké, Côte d’Ivoire. Regular sampling of insect pests and observations on rice yellow mottle virus (RYMV) disease infection throughout the year provided information on the occurrence of RYMV and potential insect vectors. RYMV incidence and grain yields varied depending on planting date, and for a given planting date, varied from one year to another. There was no evidence that RYMV incidence increases …