Search

Cycad is one of the most important cut foliage plants with several usages. This experiment was focused on increasing the vase life of cycad's cut foliage in normal storage condition. Experiment was based on a CRD with three replications. Treatments were conducted for four different levels of gibberellic acid (GA3) and benzyl adenine (BA) each one with 0, 50, 100 and 150 mg L-1, according to mentioned statistical design. In all treatments except control, silver nitrate (AgNO3) with 40 mg L-1 and 3% sucrose were used. The measured traits were; vase life, chlorophyll and carotenoid content, water loss and some external quality factors. Results showed that GA3 had significant and positive effects on increasing the vase life of cycad's cut foliage and kept the external quality in good condition. However, unlike the gibberellic acid, treatment with high concentration of BA decreased vase life of cycad's cut foliage. Also, relation between storage time, BA and GA3 on most of measured external factors like leaflet dryness and fragility, were significant. The best treatments were selected as 50 mg L-1 GA3 without BA which increased the vase life of cycad's leaves to 101 days in storage condition. [ABSTRACT FROM AUTHOR]

Danae racemosa (L.) Moench is an important cut foliage in the ornamental market. During postharvest, leaf senescence symptoms are leaf yellowing, weight loss and/or abscission of leaves. The aim of this work was to evaluate the effect of pre-treatments for 24 h with glycerol and Thidiazuron (TDZ) on Danae vase life before and after storage. Treatments were applied in vase water containing glycerol 0.1, 1 or 10 mM, 10 μM TDZ and a combined treatment of 10 μM TDZ plus 10 mM glycerol. The effect of treatments was evaluated through the determination of vase life, chlorophyll content, chlorophyll a fluorescence parameters, sucrose and total sugars content. The cut foliage were stored in sealed plastic bags and placed in a dark room at 4°C for two months. The vase life, before and after storage, was determined in a controlled chamber set to 20°C and RH 50-60% with a light intensity of 20 μmol m-2 s-1. Results demonstrated that 10 μM TDZ plus 10 mM glycerol was the most effective treatment in maintaining quality during vase life of stored and not stored cut foliage. [ABSTRACT FROM AUTHOR]

Abstract: Pelargonium (Pelargonium x hortorum) is grown as potted or bedding plants for their colourful, showy flowers and scented foliage. Absence of senescence symptoms in the leaves of Pelargonium cuttings, their capacity to initiate roots and continued growth of initiated roots is an important quality attribute. The effects of postharvest treatments with meta-topolin (mT) and thidiazuron (TDZ) to ‘Katinka’Pelargonium cuttings were investigated. Leaves treated with mT or TDZ for 5d had higher leaf chlorophyll contents than untreated controls. Exposing cuttings to mT had no effect on the rooting proportion (%) and average root diameter. Similarly, 0.05mMmT had no effect on number of roots per cutting. However, mT slightly reduced root length, root surface area and total volume of the roots. TDZ severely inhibited adventitious root formation, thus it reduced all the root parameters investigated. In conclusion, mT is very active in retarding leaf senescence, and combined with the observed ease of rooting of cuttings after mT treatment, this treatment is a suitable alternative to TDZ in delaying the onset of leaf yellowing in ornamental crops. [Copyright &y& Elsevier]

Abstract: The effects of 40, 70 or 100mgL−1 free chlorine neutral and acidic electrolyzed water (NEW and AEW) during the washing and disinfection step, on quality attribute changes during shelf life of fresh-cut mizuna baby leaves, were studied. Physiological, nutritional, enzymatic, sensory, and microbial changes throughout 11 days at 5°C were monitored. Results were compared to those reached with a conventional industrial treatment of 100mgL−1 NaClO at pH 6.5 and with a control washing with deionised water. Both NEW and AEW showed an inhibitory effect on natural microflora growth and retained the main quality attributes. Total chlorophyll content was preserved after shelf life. Initial total phenolic contents ranged between 1868 and 2518mgCAEkg−1 fw for AEW 40 and AEW 100 treatments respectively and slightly increased throughout shelf life. In contrast, after shelf life the total antioxidant activity recorded on the processing day decreased around 35%. Throughout shelf life EW induced an increase in catalase activity while superoxide dismutase activity decreased. Scanning electron microscopy of the leaves showed that neither NEW nor AEW affected their surface structure. To the best of our knowledge, the effects of NEW and AEW on bioactive quality parameters, as well as on antioxidant enzyme activities for fresh-cut baby leaves are first reported here. EW provides an alternative sanitizing technique to NaClO for maintaining the quality of fresh-cut mizuna baby leaves up to 11 days at 5°C. [ABSTRACT FROM AUTHOR]

Considering the results of these investigations from an ecological point of view, it must be stated that the chlorophyll factor does not have much bearing on the photosynthesis in plants with foliage leaves. In most of the species the chlorophyll concentration of the fully developed leaves exceeds the optimum value for the chlorophyll factor. Only in young leaves and in leaves of aurea varieties with chlorophyll concentratration lower than this value, can the chlorophyll factor be of importance for the rate of photosynthesis, but even then, only at weak light intensities which are seldom found in nature. [ABSTRACT FROM AUTHOR]