Differential effects of postharvest application of ethylene inhibitors on guava stored under ambient conditions

Abstract

Aim: To assess the efficiency of ethylene synthesis and action inhibitors on postharvest shelf life of guava fruits under ambient conditions. Methodology: Mature green guava fruits (P. guajava L. cv. Arka Mridula) were harvested and treated with ethylene inhibitors. Various physiological, physical and nutritional changes of the treated fruits in comparison with untreated ones were monitored during ambient temperature storage. Multivariate analysis approach was used for interpreting the data on quality changes during storage. Results: Significant positive correlation (p<0.01) was observed among rates of ethylene production, respiration, ripening and Hunter’s a* value. Biplot from principal component analysis of eleven parameters showed that 1-MCP (500 ppb) treated fruits were grouped together with freshly harvested fruits throughout storage period, and proved superior over other treatments in delaying ripening and quality maintenance. Seven days stored 3.0 mM Salicylic acid and 1.5 mM Sodium nitroprusside treated fruits were grouped together with 5 days stored control fruits, suggesting their effectiveness in extending the shelf life by additional two days. Interpretation: Postharvest application of 1-MCP on guava fruits can extend the shelf life by four days when compared with control. Even PCA indicated that the study of major ripening attributes (L*, a*, b*, Hue, texture, acidity, ethylene rate and respiration rate) was quite sufficient to know the ripening status of the fruits.