Abstract

                                The top-borer Scirpophaga nivella Fabr. is a major pest of sugarcane which has assumed a serious form in the sugarcane areas in Madras state. Of late this pest has increased in alarming proportions in the Pugalur Factory Zone and is also increasing in intensity of attack in the South Arcot District. The very young canes affected by this pest die out and do not survive till harvest. The canes affected at later stages survive but give juice of varying quality. This varies according to the variety and the period of harvest. In this tract (South Arcot District) there are three popular varieties of sugarcane namely Co. 419, Co. 449 and Co. 527. The three varieties mature at different stages in the crushing period. The varieties Co. 449 and 527 mature early in the season while the variety Co. 419 matures late in the season. It has been observed that in the grown up canes the top-borer attack induces early maturing since the vegetative growth is arrested. This results in variations in the quality of the juice of the affected canes, depending on the time of attack of the borer.

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