Effect of plant growth regulators on the quality of bast fibres in Abelmoschus esculentus (Linn.) Moench.

Abstract

Abelmoschus esculentus (Linn) Moench. vernacularly variously called okra, bhindi or ladies’ fingers, is a vegetable crop and a source of soft fibre which has not been commercially exploited. The use of its fibre as an admixture with jute and also in paper and cardboard manufacture is already documented. The present investigation highlights the effect of plant growth regulators like gibberelic acid (GA) and naphthalene acetic acid (NAA) on the quality of bast fibres in A. esculentus. The fibre quality was best in GA 100 + NAA 50 gm L –1 treatment. Fibre macerate studies showed an increase in fibre length and the slenderness ratio was also high. The Runkel ratio for the above treated fibre was between 1 and 2 rendering it suitable for the textile industry. Proximate analysis of retted fibres revealed a lower moisture and ash content and an increase in wax content. Fourier transform infra-red (FTIR) spectroscopy analysis registered a high crystallinity index. The physico-mechanical properties showed considerable improvement of fibre quality. Considering the above criteria, GA100 + NAA 50 gm L –1 treatment brought about advantageous changes for improving the quality of fibres. This study is significant in promoting the exploitation of a non-conventional bast fibre source for use in textile industry.