BIO-EFFICACY OF CARBOFURAN 5G AGAINST BRINJAL SHOOT AND FRUIT BORER APPLIED AT DIFFERENT ROW COMBINATIONS

Abstract

An experiment was undertaken to determine the suitable pattern of carbofuran application for brinjal cultivation and minimize the application of carbofuran for maximum protection against brinjal shoot and fruit borer (BSFB). The experiment was conducted at the research field of Soil Science Department, Bangabandhu Sheikh Mujibur Rahman Agricultural University (BSMRAU), Gazipur during the period from September 2008 to March 2009. The experiment was laid out in RCBD with 4 treatments and 3 replications. Considering 6m x Sm plot size for each treatment and 60 cm x 7S cm plant spacing with 40 days old brinjal seedlings. The lowest percent of shoot infestation (1.24%) was recorded where carbofuran 30 kg/ha (furataf SG used @ 90g/ 30 m'; T,) was applied in every plant of every row. It was followed by carbofuran IS kg/ha (furatafSG used @4Sg/30m'; T,) was applied in every plant of every alternate row. But there was no significant difference of percent shoot infestation between where carbofuran was applied in every plant of every row and in every plant of every alternate row. However, the highest shoot infestation (3.02%) was recorded where carbofuran 7.50 kg/ha (furataf SG used @ 22.50g1 30 nr'; T4) was applied in every plant of three alternative rows and followed by earbofuran 11.25 kg/ha (furataf SG used @ 37.7Sg/30 m'; T3) was applied in every plant of two alternative rows. Fruit infestation both in terms of number and weight followed the same trend as in shoot infestation and having no significant difference between these two treatments. The highest percent fruit infestation (36.S3%) by number was recorded in where carbofuran was applied in every plant of three alternative rows followed by carbofuran was applied in every plant of two alternative rows. The highest yield (37.67 t/ha) was obtained from where carbofuran was applied in every plant of every row and the second highest yield (37.58 t/ha) was recorded where carbofuran was applied in every plant of every alternate row, although there was no significant difference between these treatments in respect to yield. Significantly, the lowest yield (33.S6 t/ha) was recorded where carbofuran was applied in every plant of three alternative rows in which the maximum distance was maintained in carbofuran application pattern. The highest net return (4,08,SOO Tk/ha) and cost benefit ratio (1.19) was found where earbofuran was applied in every plant of every alternate row. In view of different row combinations, the higher net return and cost benefit ratio may come from where carbofuran application in ring furrow to every plant of one alternate row would be the best option to be utilized in BSFB management programs.