EFFECT OF POLYAMINES AND ALTERNATIVE OXIDASE INHIBITORS ON RIPENING AND SHELF LIFE OF BANANA (Musa spp.)

Loading...
Thumbnail Image
Date
2003
Journal Title
Journal ISSN
Volume Title
Publisher
ACHARYA N.G. RANGA AGRICULTURAL UNIVERSITY RAJENDRANAGAR, HYDERABAD
Abstract
Banana being a typical climacteric fruit is more prone for deterioration and has less shelf life. So far, no systematic effort has been made to study the effect of various post harvest application of polyamines and AOX inhibitors on prolonging shelf life in different varieties of banana. Hence, a set of four experiments were conducted to study the effects of post-harvest treatments with polyamines (putrescine, spermidine, spermine), AOX inhibitors (propyl gallate and salicyl hydroxamic acid) and their combination on the shelf life and ripening of banana varieties viz. Poovan, Robusta, Tella Chakkarakeli, Elakki Bale and KBS – 4 at Department of Horticulture, College of Agriculture, Rajendranagar, Hyderabad. The fruits were kept at ambient temperature. Ripening was delayed in the fruits treated with SPE 100 + PG 100 combination followed by both SPE 100 and PG 100 when treated individually. SPE 100 + PG 100 recorded lower rate of total respiration (144.20  moles\kg\hr in KBS–4; 158.92  moles\kg\hr in Robusta); low alternative respiration (38.51  moles\kg\hr in KBS – 4; 41.28  moles\kg\hr in Robusta); low lipoxygenase activity (0.973 U\mg protein in KBS – 4; 1.093 U\mg protein in Robusta); high catalase activity (0.135 U\mg protein in KBS – 4; 0.145 U\mg protein in Robusta) and high peroxidase activity (3.605 U\mg protein in KBS – 4; 3.552 U\mg protein in Robusta) compared to other treatments and hence delayed ripening with delayed ethylene outburst leading to increased shelf life. Lowest LOX activity in SPE 100 + PG 100 might be due to propyl gallate being a very effective inhibitor of the alternative pathway respiration and also an excellent inhibitor of LOX as well. Inhibition of LOX activity has been generally been associated with its ability as an antioxidant to remove free radicals formed during the course of the reaction. Shelf life increased with post-harvest application of polyamines (especially SPE 100) and alternative oxidase inhibitors (especially PG 100). In var. KBS – 4, maximum shelf life (18 days) was observed with both SPE 100 alone and PG 100 alone when compared to control (15 days); in var. Robusta, it was 15 days compared to control (12 days) in var. Poovan, it was 12 days compared to control (9 days); in var. Tella Chakkarakeli, it was 9 days compared to control (6 days) and in var. Elakki Bale, it was 9 days compared to control (6 days). But with combination treatment i.e., with SPE 100 + PG 100, an increase in shelf life by three more days was observed in both KBS – 4 (21 days) and Robusta (18 days) varieties. PLW was highest in control and least in SPE 100 and PG 100. Lowest PLW was recorded in KBS-4 followed by Robusta and highest PLW in Tella Chakkarakeli and Elakki Bale. Poovan was intermediate. The varieties having longer shelf life (KBS – 4 and Robusta comparatively) had slow and gradual increase in PLW whereas the PLW was significantly rapid in varieties having lower shelf life viz., Poovan, Tella Chakkarakeli and Elakki Bale. The treatments viz. SPE 100 and PG 100, which prolonged the shelf life had slow rate of PLW than other treatments and control. PLW was lowest in SPE 100 + PG 100 (7.25% in KBS – 4; 11.88% in Robusta) compared to control (9.86 %in KBS – 4; 14.42 in Robusta). TSS was lowest in SPE 100 + PG 100 (15.58 oBrix in KBS – 4; 14.30 oBrix in Robusta) compared to control (17.20 oBrix in KBS – 4; 16.35 oBrix in Robusta).Titrable acidity was highest in SPE 100 + PG 100 (0.25% in KBS –4; 0.23% in Robusta) compared to control (0.17% in KBS – 4; 0.19% in Robusta). Reducing sugars was lowest in SPE 100 + PG 100 (6.19% in KBS – 4; 6.19% in Robusta) compared to control (6.88% in KBS – 4; 6.83% in Robusta).Rate of ethylene production was highest in SPE 100 + PG 100 (8.42 l\kg\hr in KBS – 4; 8.31 l\kg\hr in Robusta) compared to control (7.48 l\kg\hr in KBS – 4; 7.70 l\kg\hr in Robusta). SPE followed by PG maintained low lipoxygenase activity, low total and alternative respirations but high ethylene production; high rates of catalase and peroxidase activity. The enhancement of alternative respiration was seen in all the treatments with a peak on a particular day but at reduced levels in SPE 100 + PG 100, SPE 100 and PG 100 compared to control. This peak was also synchronised with total respiration i.e., respiratory climacteric and commensurate with ethylene levels. Suppression and delayed respiratory climacteric with spermine and inhibition of alternative respiration by propyl gallate might be the cause for prolonged storage life in the combination treatment.
Description
Keywords
EFFECT, POLYAMINES, ALTERNATIVE, OXIDASE, INHIBITORS, RIPENING, SHELF LIFE, BANANA
Citation
Collections