Abstract

The yellow mite, Polyphagotarsonemus latus Banks (Acari: Tarsonemidae) is one of the most serious pests of jute crop (Corchorus olitorius L.) in Bangladesh. Jute plants of tossa (C. olitorius) varieties were considered as treatments including, O-9897,O-72,OM-1 and O-795. The paired plot treatments (miticide treated and miticide untreated control) were laid out under net house condition. The impact of yellow mite, were studied on three stages of jute plants: 60, 90 and 120 DAS. The higher number of mite stages observed up to 90 DAS then declined afterward up to 120 DAS in var. OM-1 among four C. olitorius varieties. A damage index scale (0-5) was to assess yellow mite injury to jute plants. The percent infestation and damage index was also used to relate yellow mite injury to different yield contributing characters of plants infested at three different phenological stages. The yield contributing characters of untreated plots showed significant damage at 60, 90 and 120 DAS in C. olitorius varieties compared to treatment plots. The highest fibre yield losses due to mite infestation was found in the variety OM-1 (74.71%) followed by O-795 (72.98%), O-72 (68.14%) and the lowest was in O-9897 (50.11%); the highest stick yield losses in OM-1(57.18%) followed by O-795 (49.43%), O-9897 (49.35%), the lowest was in O-72(48.92%)and the highest seed yield losses in O-795(64.34%)followed by O-72(48.21%),OM-1(44.55%), he lowest was in O-9897(42.69%) under net house condition. High yellow mite population in the untreated check decreased plant growth and showed significant fibre and stick weight loss in the variety OM-1 and seed weight loss in the variety O-795.

Key words: Polyphagotarsonemus latus, Corchorus capsularis, abundance, yield.