Temperature, Field Protection and Bioplastic Biopesticide Treatments Shape Mango Postharvest Disease Dynamics: An Integrated Univariate and Multivariate Analysis

Abstract

Aims: This study evaluated the effects of storage temperature, field protection, and postharvest treatments on mango disease severity and incidence. Study Design: A factorial experiment was conducted using three treatments: water (T0), bioplastic (T1), and a bio‑bactericide combining bioplastic and essential oils (T2). Two field histories were considered, namely fruits that had been protected in the orchard (B1) and fruits that had not been protected (B2). Storage was carried out at two contrasting temperatures, 8 °C and 30 °C. Disease severity, scored on a 0–9 scale and converted to percentages, and incidence, expressed as the percentage of infected fruits, were monitored weekly from S0 to S8. Methodology: Lemongrass (Cymbopogon citratus) essential oil was extracted via steam distillation from plant material. Bioplastic matrices were synthesized from native potato starch. The essential oil was subsequently encapsulated within the bioplastic using mechanical agitation followed by extrusion processing to formulate the biopesticide The data were analyzed using descriptive statistics, factorial ANOVA, and principal component analysis (PCA). Tables and figures were prepared to illustrate temporal dynamics and treatment effects. Results: At 8 °C, the bio‑bactericide (T2) almost completely suppressed disease in B1 and substantially reduced severity and incidence in B2. At 30 °C, T2 delayed symptom onset but did not prevent convergence to high severity and incidence by week 8. The bioplastic film alone (T1) was largely ineffective, showing patterns similar to the water control (T0). PCA separated treatments along PC1, which represented overall disease burden, and PC2, which represented the timing of onset, highlighting the strong influence of temperature and field protection. Conclusion: Bio‑bactericides are highly effective under cool storage, especially when combined with field protection, but under warm conditions they primarily delay disease progression. Cold storage therefore remains indispensable for reliable postharvest control.