GENOTYPIC AND SEASONAL INFLUENCE ON THE POPULATION DYNAMICS OF OKRA SUCKING PESTS

ABSTARCT: The study was carried out to record the genotypic and seasonal influence on the population dynamics of okra sucking pests viz., Aphid (Aphis gossypii), whitefly (Bemisia tabaci), jassid (Amrasca biguttula biguttula) and red spider mite (Tetranychus urticae) during two cropping seasons (rabi 2019-2020 and kharif 2020) at Entomology Research Field, SAU campus, Sylhet, Bangladesh. In both seasons, four Japanese okra genotypes (JO3, JO5, JO7 and JO9) and two local okra varieties (BARI Dherosh-1 and BARI Dherosh-2) were used as treatments of the study. The genotype JO5 was found less susceptible to insect and mite pests in both seasons but its fruit bearing capacity was very low. The highest yield was found in BARI Dherosh-2 and JO7 in both seasons. Okra sucking pests were found more prevalent during kharif 2020 than those of the rabi 2019-2020. Red spider mites were absent during rabi 2019-2020. Aphid, whitefly, jassid and red spider mite showed significant negative relationship with rainfall during kharif 2020. To control the okra sucking pests, effective management techniques need to be adopted at the beginning of kharif-1 (March - April) when the pest infestation f irst appears. 

Keywords: Accession, seasonality, weather parameter, correlation coefficient.