Effect of different ethylene concentrations on ripening behaviour of banana (CV. GRAND NAINE)

Introduction

Banana is an important fruit crop contributing substantially to human nutrition. Ripening is a complex genetically regulated process that results in changes in colour, flavour, aroma, texture, and nutritional quality. As ripening progresses, chlorophyll degradation and sugar accumulation lead to softer and sweeter fruits.

Materials and Methods

Banana fruits of cv. Grand Naine were harvested at the green mature stage and subjected to ethylene treatments using Ripylene canisters. The experiment followed a Factorial Completely Randomized Design with three replications. DA meter readings were recorded daily.

Results and Discussion

The data pertaining to DA meter readings of banana fruits Cv. Grand Naine at ambient temperature as influenced by postharvest Ethylene concentrations, and number of pulsings are presented in tables. It is evident from the data that, the DA reading showed significantly decreased as the ripening advanced during storage at ambient conditions. DA meter measures the chlorophyll content in a fruit and, as a consequence, its state of ripeness. The index of absorbance difference (IAD) decreases in value during ripening by absorbency properties of the fruit, until it reaches very low value (0.00), when ripening was complete. Each kind of fruit and cultivar has specific DA values according to the different phases of maturation. (Ziosi et al., 2008; Noferini et al., 2008) [1, 2] . It is evident from the data that, the DA meter reading showed decreasing trend as the ripening process advanced. Among different Ethylene concentrations on 1 st day (Table 1) maximum was recorded in ethylene @ 50 ppm (1.80) and ethylene @ 75 ppm (1.80) while minimum was recorded in ethylene @ 125 ppm (1.66). On 2 nd day (Table 2) highest was recorded in ethylene @ 100 ppm (1.65) and ethylene @ 50 ppm (1.64) while lowest was recorded in ethylene @ 75 ppm (1.44). On 3 rd day (Table 3) highest was recorded in ethylene @ 100 ppm (1.45) and lowest was recorded in ethylene @ 75 ppm (1.09). On 4 th day (Table 4) highest was recorded in ethylene @ 100 ppm (1.26) lowest was recorded in ethylene @ 75 ppm (0.95). Among different number of pulsings on 1 st day (Table 1) maximum was recorded in 6 pulsings in 24 hours @ 4 hrs. interval (1.85) while minimum was recorded in 1 pulsing in 24 hours @ 24 hrs. interval (1.72) and 2 pulsings in 24 hours @ 12 hrs. interval (1.72). On 2 nd day highest was recorded in 6 pulsings in 24 hours @ 4 hrs. interval (1.63) while lowest was recorded in 1 pulsing in 24 hours @ 24 hrs. interval (1.47). On 3 rd day (Table 3) highest was recorded in 6 pulsings in 24 hours @ 4 hrs. interval (1.42) while lowest was recorded in 2 pulsings in 24 hours @ 12 hrs. interval (1.18). On 4 th day (Table 4) highest was recorded in 6 pulsings in 24 hours @ 4 hrs. interval (1.26) and lowest was recorded in 2 pulsings in 24 hours @ 12 hrs. interval (1.00%). The interaction between Ethylene concentrations and number of pulsings showed significant variation (Table 1 to 5). Significantly high DA reading was recorded on 1 st day (Table 1) in 50ppm ethylene with 6 pulsings in 24 hours @ 4 hrs. interval (1.97) and 100 ppm ethylene with 4 pulsings in 24 hours interval @ 6 hrs. interval (1.97) while lowest was recorded in 100 ppm ethylene with 1 pulsing in 24 hours @ 24 hrs. interval (1.63).On 2 nd day (Table 2) highest was recorded in 100 ppm ethylene with 4 pulsings in 24 hours @ 6 hrs. interval (1.93) and lowest was recorded in 75 ppm ethylene with 2 pulsings in 24 hours @ 12 hrs. interval (1.38).On 3rd day (Table 3) highest was recorded in 100 ppm ethylene with 4 pulsings in 24 hours @ 6 hrs. interval (1.77) and lowest was recorded in 75 ppm ethylene with 2 pulsings in 24 hours @ 12 hrs. interval (0.93). On 4 th day (Table 4) highest was recorded in 100 ppm ethylene with 4 pulsings in 24 hours @ 6 hrs. interval (1.58) and lowest was recorded in 75 ppm ethylene with 2 pulsings in 24 hours @ 12 hrs. interval (0.87) which is on par with 75 ppm ethylene with 4 pulsings in 24 hours @ 6 hrs. interval (0.88) The mean values recorded among the bananas treated with ethylene concentrations and number of pulsings during 5 th day of storage tabulated at Table 5. The similar decreasing trend in respect of DA meter reading with advancement of ripening during storage was observed. Similar results were reported by Peter, (2011) [3] who noticed a decreasing trend in DA reading with degradation of chlorophyll content in Apple and in Mango Cv. Manila (Maria Soledad, 2014) [4] . The results reported by Lorenzo et al. (2012) [5] stated that the DA index allows separation of the fruits in different categories of maturation in Mango. Similar results were demonstrated by Noferini et al. (2008) [2] who reported that in Apple, the DA was found to be a reliable parameter for monitoring on tree apple ripening decreasing index ranges corresponded to increasingly advanced stages of ripening.

References

1. Ziosi V, Noferini M, Fiori G, Tadiello A, Trainotti L, Casadoro G, et al. A new index based on VIS spectroscopy to characterise the progression of ripening in peach fruit. Postharvest Biol Technol. 2008;49:319-329.
2. Noferini M, Fiori G, Ziosi V, Costa G. The index of absorbance difference (IAD) is a reliable marker for monitoring on-tree ripening evolution in apple fruit. Poster presented at: Isafruit General Assembly; 2008; Girona, Spain.
3. Peter T. Evaluation of non-destructive instruments for assessing apple maturity and quality. Agriculture and AgriFood Canada; 2011. p. 1-21.
4. Maria Soledad. Fruit ripening/scald relationship in apple. Bologna: Alma Mater Studiorum, University of Bologna; 2014.
5. Lorenzo S, Rizzolo A, Vanoli M, Grassi M, Eccher ZP, Meirelles, et al. Optical properties of pulp and skin in Brazilian mangoes in the 540-900 nm spectral range: implication for non-destructive maturity assessment by time-resolved reflectance spectroscopy. In: International Conference for Agricultural Engineering; 2012. 15(2):123127.