Economics and loss of by-products of coconut due to eriophyid mite, Aceria guerreronis (Keifer) damage

Abstract

Coconut fiber is obtained from the fibrous husk (mesocarp) of the coconut (Cocos nucifera) and the coir

industry depends on this versatile natural fiber. Efforts were  made in this study to evaluate the effect of

eriophyid mite,  Aceria guerreronis (Keifer) damage on the out-turn and quality of coconut fiber. An out-turn of 100.5, 89.7, 81.0, 68.6 and 60.1 kg of white fiber was obtained from 1,000 nuts infested by

eriophyid mite belonging to grade 1, 2, 3, 4 and 5, respectively. A reduction in the out-turn of fiber could

be a consequence of nut malformation or cracks formed on the husk surface due to desapping by  A.

guerreronis  at the young button stage of the nuts. A significant negative correlation was observed

between the quantity of rope made out of the extracted fibers and the nut damage grade. A quantity of

90.8 and 49.7 kg of rope were obtained by using white fibers extracted from 1,000 nuts of grade 1 and 5,

respectively. Fibers extracted from nuts belonging to grade 1 and 5 had a tensile strength of 52.1 and 15.7

kg, respectively. A fiber length of 10.8 cm and a fiber diameter of 0.4 mm were noticed in the fibers

extracted from severely infested nuts (grade 5).

Key words: Coconut, Eriophyid mite,  Aceria guerreronis,  fiber out-turn, tensile strength