Influência do etileno e do 1-MCP na senescência e longevidade das inflorescências de esporinha

Abstract

A aplicação de etileno e do 1-metilciclopropeno (1-MCP) têm efeitos marcantes sobre a abscisão e a longevidade em vaso das inflorescências de esporinha (Consolida ajacis). O etileno acelerou a abscisão das flores em concentrações iguais ou superiores a 1,0 mg L -1 de Ethrel quando pulverizado por duas horas em intervalos de 30 minutos. As concentrações de 100 e 1.000 mg L -1 de Ethrel induziram imediata abscisão das flores, reduzindo a longevidade de 4,4 dias nas flores-controle para 1,8 e 1,2 dias respectivamente. O tratamento com 1-MCP (0,5 g m -3 de SmartFresh TM ) foi eficiente em retardar o início da abscisão das flores, mesmo quando 100 mg L -1 Ethrel foi pulverizado imediatamente após a aplicação do 1-MCP. Flores tratadas exclusivamente com 1-MCP ou tratadas antes do Ethrel tiveram a longevidade estendida em 33% em relação ao controle. Houve redução da eficiência do 1-MCP, em estender a longevidade, se aplicado após a pulverização com Ethrel, comparado com o tratamento de 1-MCP isoladamente ou 1-MCP seguido de Ethrel. Esse efeito demonstra que 1-MCP não foi capaz de bloquear completamente os receptores do etileno.Palavras-chave: abscisão, vida de vaso, Ethrel, SmartFresh TM . ABSTRACT INFLUENCE OF ETHYLENE AND 1-MCP ON SENESCENCE AND LONGEVITY OF CONSOLIDA AJACIS INFLORESCENCESEthylene and 1-methylcyclopropene (1-MCP) had strong influence on the Consolida ajacis flower abscission and longevity. Ethylene was able to induce abscission of the flowers in concentrations equal or above 1,0 mg L -1 Ethrel, when sprayed over two hours at 30 minutes interval. Concentrations of 100 and 1000 mg L -1 Ehtrel induced fast flower abscission, reducing the longevity from 4.4 days on the control flowers to 1.8 and 1.2 days, respectively. Treatment with 1-MCP (0.5 g m -3 SmartFresh TM ) was efficient in delaying the beginning of flower abscission, even when the inflorescences were sprayed with 100 mg L -1 Ethrel just after the 1-MCP treatment. Flowers treated exclusively with 1-MCP had the longevity extended in 33% as compared to the control treatment. Similar results were observed when the flowers were treated with 1-MCP followed by Etrhel. Compared to 1-MCP treatment alone or 1-MCP followed by Ethrel, there was a reduction of flower longevity when 1-MCP was applied after the Ethrel. This effect shows that 1-MCP was not able to completely block all the ethylene receptors, if Ehtrel was applied previously to 1-MCP.

Longevity ofEpidendrum ibaguenseflowers as affected by pre-loading treatments and vase solution

“…Such an effect persists within the plant tissues, even after the STS treatment is over. This is not true for 1-MCP-treatment (Blankenship and Dole, 2003), as can be observed in Consolida ajacis and Pelargonium peltatum flowers, where 1-MCP had a transitory effect in delaying flower wilting and abscission (Cameron and Reid, 2001;Santos et al, 2005). Since 1-MCP was more efficient than STS treatment (Table I), it is probable that E. ibaguense flowers do not develop new ethylene receptors after harvest.…”

Longevity of torch ginger inflorescences with 1-methylcyclopropene and preservative solutions

“…The abscission and senescence processes may be accelerated by the increase of the ethylene yield (SANTOS et al, 2005), which exerts influence upon the tissue turgidity, accelerating the flower wilt (MAYAK et al, 1977). According to Ciardi and Klee (2001), the sensitivity and response level to the ethylene are dependent on the developmental and perceptive stage of the plant's organ.…”

Postharvest physiology of cut flowers

“…Days for 50% of flower abscission or wilting. Means with the same letter are similar according to the Tukey's test at 5% probability(Santos et al, 2005).…”