Effect of accel on the vase life and post harvest quality of alstroemeria (alstroemeria aurantiaca l.) cut flowers

Freshly cut flowering stems of Alstroemeria ‘Yellow King’ and ‘Marina’ were placed in glass jars containing solutions of Accel at 0, 25, 50, 75 and 100 mg/litre BA equivalent and arranged in a completely randomised design with 3 replicates. The effect of Accel on the vase life and qualityof Alstroemeria was investigated. Flowers held in Accel at 25 or 50 mg/litre BA equivalent consistently increased the number of days to full opening of primary florets and delayed the onset of flower senescence as measured by days to 50 % petal fall and days to 50 % leaf yellowing. Accel at 25mg/litre BA equivalent significantly increased the leaf nitrogen and chlorophyll content of Alstroemeria cut flowers. High Accel concentrations of 50, 75 and 100 mg/litre BA equivalent reduced significantly the leaf water content of Alstroemeria cut flowers. Accel at 75 and 100 mg/litre BA equivalentincreased leaf dry weight of Alstroemeria cut flowers. Our results indicate that Accel at 25 mg/litre BA equivalent has the potential to be used as a commercial cut flower preservative solution for delaying flower senescence, prolonging the vase life and enhancing post harvest quality of Alstroemeria cut flower

Effect of accel, sucrose and silver thiosulphate on substrate utilization in cut tuberose (Polianthes tuberosa L.) flowers

This study was undertaken to investigate the effect of Accel™, sucrose and silver thiosulphate (STS) on the dry weight, accumulation of sucrose and reducing sugars in cut tuberose (Polianthes tuberosa L) petals at various positions along the spike. Cut stems of Tuberose were held in optimum treatments that prolonged their vase life (Hutchinson et al., 2003): continuous holding in 25 mg/L BA equivalent of Accel; pulsing in 20% sucrose for 24 hrs and subsequently holding in either deionized water (DIW) or in 25 mg/L BA; pulsing in 2 mM STS for 1 hr and subsequent holding in DIW. The middle and bottom florets of cut flowers held in DIW were heavier than the top florets. Pulsing tuberose cut flowers in sucrose or in STS improved the dry weights of the middle and bottom florets in the 1st 3 days but up to 6 days of top florets. Florets of cut flowers pulsed in sucrose and subsequently held in Accel were heavier than those subsequently held in DIW or those held continuously in Accel. Sucrose, STS and Accel increased floret opening but had varied influence on the accumulation of sucrose and reducing sugars in petals of florets along the spike. Cut tuberose stems pulsed in sucrose and subsequently held in either DIW or 25 mg/L BA equivalent of Accel accumulated the largest amounts of sucrose and reducing sugars. Pulsing cut tuberose flowers in 10% sucrose and subsequently holding them in Accel or DIW or pulsing in STS, while having no influence on sucrose levels in bottom florets, significantly increased levels in top florets for the 1st 3 days before a sharp decline in petals pulsed in sucrose. The main difference was that while most of the sucrose accumulated in the middle florets, reducing sugars was concentrated on the bottom florets along the spike. Unexpectedly, pulsing stems in STS or holding them in Accel had no significant influence on levels of sucrose or reducing sugars within the 9 days of testing even though most florets had opened by this time. The results of the present study suggest that while sucrose had a direct influence on accumulating of sucrose and reducing sugars in florets, Accel and STS improved vase life and floret opening in cut tuberose stems either indirectly through substrate mobilization and increased metabolism or may have played another different role other than substrate mobilization

Effect of accel, sucrose and silver thiosulphate on the water relations and post harvest physiology of cut tuberose flowers

This study investigated the influence of cytokinins, gibberellins, sucrose and silver thiosulphate on water relations and post-harvest physiology of cut tuberose (Polianthes tuberosa L) flowers. Tuberose flowers held in de-ionised water (DIW) had a vase life of 13 days with 63% floret opening. Addition of gibberellins (GA4+7) in the vase solution had no effect on vase life or floret opening along the spike. Pulsing of the cut flowers with 10% sucrose for 24 hr before transfer to DIW improved their vase life by 4 days and improved the floret opening by 21% above DIW controls. Addition of Benzylaminopurine (BA) at low concentrations (25-50 mg L-1) improved vase life of the cut tuberose stems while higher concentrations (75-100 mg L-1) gave no improvement. A 24 hr pulse in 10% sucrose improved the vase-life by 3.6 days and floret opening by 13%. Pulsed stems transferred to holding solutions containing various concentrations of BA improved vase life by an extra 3 days at BA concentration of 25 mg L-1. Higher BA concentrations gave no significant (P>0.05) improvement over the pulsed stems. However, floret opening was greater at 25 and 50 mg L-1 BA (

Effect of levels and timing of application of gibberellic acid on growth and yield components of common beans

This study was conducted to determine the effect of levels and timing of application of gibberellic acid (GA3) on growth and yield components of common beans (Phaseolus vulgaris L.). Experiments were conducted at the Field Station Farm at the Faculty of Agriculture, University of Nairobi, Kenya during 1997 and 1998. "Mwezi moja" bean cultivar was used in study. Gibberellic acid (GA3) was sprayed at 0, 2.5, 5.0 and 7.5 mg l-1 to whole bean plants at 7, 14 or 28 days after emergence (DAE). The effect of GA3 and timing of application on growth, yield and yield components was significant (

Effects of Ethephon on the Growth, Yield and Yield Components of Beans (Phaseolus vulgaris L.)

Two experiments to determine the effects of timing and levels of application of ethephon on the growth and yield of common bean (Phaseolus vulgaris L). were conducted. Bean cultivar \'Mwezi moja\' was used. Four levels of ethephon (0, 100, 200 and 300 mg/l) were sprayed to the plants at 7, 14 or at 28 days after emergence (DAE). Application of ethephon at all the three timings led to reduced plant height. Application of ethephon at 28 DAE reduced the leaf area index (LAI), fractional solar radiation interception, shoot dry mass and total dry mass. Root dry mass was not affected by ethephon application. Application of ethephon particularly at 28 DAE reduced yield and number of pods per plant. Application at 7 and 14 DAE in experiment 1 and 28 DAE in both experiments increased the number of seeds per pod. Ethephon application at 14 DAE increased the 100-seed mass in experiment 1 but reduced it in experiment 2. Most reduction in 100-seed mass occurred with application at 28 DAE. The harvest indices were reduced by application of ethephon at 28 DAE in both experiments and 14 DAE in experiment 1. It was concluded that ethephon (ethylene) application did not have any beneficial effects in bean production. KEY WORDS: Beans; ethephon; growth; yield and yield components. J. agric. Sci. technol. Vol.5(1) 2003: 22-3