Search
Search Results
-
1-MCP and STS as ethylene inhibitors for prolonging the vase life of carnation and rose cut flowers
101-107.Views:495The effect of STS and 1-MCP on the postharvest quality of carnation and rose cut flowers was studied. Cut flowers of Dianthus c..aryophyllus L. cv. Asso and Rosa hybritia cv. Baroness were treated with silver thiosulfate (STS) at 0.4 mM with sucrose at 50 g 1-t and 1-methylcyclopropene ( I -MCP) at 0.5 g m-3 for 611.
Pretreatment with STS and 1-MCP significantly extended the vase life and minimized the % loss of initial weight of carnation and rose cut flowers comparing to the untreated control. The two chemicals applied inhibited the chlorophyll degradation and carbohydrate loss and hence, significantly improved the postharvest quality of carnation and rose cut flowers comparing to the control. Ethylene production by cut flowers was inhibited as a result of using these chemicals. In general, there were no differences between STS and (-MCP but the later does not have the heavy metal implications of STS treatment, and hence, using 1-MCP pretreatment for extending the vase life of carnation and rose cut flowers was recommended.
-
Skin colour and softening synchronization during ripening of three avocado cultivars
126-133.Views:0Skin colour-softening de-synchronization during the early season remains a major quality concern in ‘Hass’ avocado, leading to consumer dissatisfaction and market losses. This study evaluated whether Hass-type cultivars ‘Carmen’ and ‘Maluma’ exhibit de-synchronization between skin colour and mesocarp softening as compared to ‘Hass’ avocado. The study was conducted using fruit harvested from a ZZ2 Moeketsi commercial farm in Tzaneen, Limpopo, South Africa. The ‘Carmen’ and ‘Maluma’ cultivars were harvested in April 2024, while the ‘Hass’ cultivar was harvested in May 2024. The harvested fruits were stored at 5.5 °C for 28 days. After cold storage, fruit were held at ambient temperature to induce ripening. Firmness declined significantly in all cultivars (p < 0.001), with ‘Carmen’ softening earlier and ‘Maluma’ showing a gradual softening pattern. Skin colour changed from green to purple and black; however, colour development was more pronounced and closely aligned with softening in ‘Carmen’ and ‘Maluma’. Chlorophyll and carotenoids decreased, whereas anthocyanin increased during ripening, with a stronger correlation between colour, firmness, and pigment changes in ‘Carmen’ and ‘Maluma’. These results indicate better skin colour-softening synchronisation in ‘Carmen’ and ‘Maluma’, supporting their suitability for early season export programs.
-
Rhizogenesis in in vitro shoot cultures of passion fruit (Passiflora edulis f. flavicarpa Deg.) is affected by ethylene precursor and by inhibitors
47-54.Views:322The effects of the ethylene precursor ACC and two inhibitors, AgNO3 and AVG, on root formation were tested in in vitro shoots of passion fruit (Passiflora Midis f.flavicalpa Deg.). The organogenic response was assessed on the basis of percentage of shoot-forming. roots, root number and length. The time course of ethylene production was also monitored. ACC inhibited root formation by delaying root emergence and increasine, callus formation at the basis of the shoots. In addition, ACC caused a marked increase in ethylene production, coupled to leaf chlorosis and senescence with lower rooting frequencies, number and length of roots. IAA supplementation increased ethylene production. Both ethylene inhibitors, AgNO3 and AVG, at appropriate concentrations reduced callus formation at the basis of shoots. AVG increased the number of roots per shoot, but drastically reduced length of differentiated roots. Regarding to leaf pigments, ACC promoted a marked reduction on carotenoids and total chlorophyll, whereas AVG and AgNO3 delayed explant senescence and pigments degradation, not differing from IAA supplemented and non-supplemented control treatments. The results confirm previous reports on the beneficial effects of ethylene inhibitors on in vitro rooting and suggest its reliability to be used as an alternative approach to evaluate sensitivity of Passiflora species to ethylene.
