長壽花貯運條件及增進貯後品質之方法

Abstract

本研究探討貯運溫度與花朵發育狀態對長壽花貯後品質之影響，與導致貯後下位葉黃化與花朵消蕾之原因，及蒸散抑制劑或生長調節劑於提昇貯後品質之效果。 將三寸盆長壽花依小花綻放率，依開花率分成stage 1(0%)、stage 2(10±5%)與stage 3 (35±5%)，3種花朵生育階段。重辦長壽花‘Mona’不論於何種生育狀態下分別以5、10或15℃暗貯7或14天後，皆以10℃暗貯7天後的開花率較高、消蕾率較低與下位葉黃化數較少，故貯後觀賞品質表現最佳；同一貯藏溫度則以stage 3之表現優於stage 1和stage 2。‘Naomi’於stage 2或stage 3，及‘Gabrielle’、‘Jodie’與‘Karen’在stage 3時，經5、10或15℃暗貯7或14天後的品質表現，亦以10℃暗貯7天者表現最佳；同一貯藏條件亦以stage 3之表現優於stage 2。綜合上述顯示10℃為長壽花最適當的貯運溫度，而7天為最適宜貯期。上述五品種長壽花皆於stage 3，經10℃暗貯7天後之觀賞表現最佳，其開花率可達84.2%以上，下位葉黃化數與消蕾率最低，故stage 3約35±5%的開花率時為長壽花最適貯運的花朵生育狀態。 比較五品種長壽花在stage 3的貯後品質，‘Karen’與‘Jodie’無葉片黃化情形，‘Naomi’及‘Gabrielle’則會在下位葉片尖端出現局部的黃化，而‘Mona’卻會發生嚴重的下位葉黃化現象。以袖套包裝暗貯後的品質皆比無袖套包裝者差，將‘Mona’、‘Gabrielle’與‘Naomi’噴施ethephon 100或300 ppm 於10℃暗貯藏7天後，皆會發生下位葉黃化與消蕾現象。另將‘Mona’處理ABA 50 μM後亦有下位葉黃化與花苞消蕾的情形，推論長壽花在暗貯後的下位葉黃化與花苞消蕾可能與乙烯及ABA有關，進而影響了貯後的開花率與觀賞品質。於貯前薰蒸0.2、0.4或0.8 ppm的1-MCP 與25或50 μM的Fluridone皆可延緩下位葉的黃化與花苞的消蕾，其中以1-MCP的抑制效果較佳，隨處理濃度的增加而提高，顯示下位葉的黃化與花苞消蕾受乙烯的影響較ABA大。 雖1-MCP與Fluridone皆能延緩貯後的黃化與消蕾，但貯後1-MCP處理組開花率約53.0%，Fluridone處理組約58.0%，皆低於60%；若於噴施蒸散抑制劑(協養旺-207) 4或8 mg•L-1雖可提高氣孔阻力，但無降低蒸散作用及減緩貯後下位葉黃化及消蕾的作用，對提高開花率與觀賞品質的效果不佳。 於貯前處理生長調節劑BA 25、50、100 μM與GA3 100 μM及GA4+7 25、50 μM或Promalin(為1.8% GA4+7 + 1.8% BA) 50、100 mg•L-1皆可有效降低貯後的葉片黃化數與花苞消蕾率。當BA 50 μM與GA3 50 μM混合處理時，可使黃葉數從16.5片降至2.8片、消蕾率從27.7%降至10.8%，比單獨處理BA 100 μM或GA3100 μM佳；可能因BA與GA3有協同之作用，因而只需單獨處理時的一半濃度即可達到抑制葉片黃化的效果。除GA3 100 μM處理組之78.3%開花率，高於對照組外，BA 100 μM及BA 50 μM + GA3 50 μM處理組，皆會導致花苞畸形及花朵展開度不佳，開花率僅有43.0~45.8%。而BA 25 μM或50 μM處理組貯後黃葉數為3.0~4.8開花率75.9~79.6%，消蕾率為20.4~24.1%，比Promalin或GA4+7處理組差。 對提高長壽花貯後品質之效果，以Promalin 50 mg•L-1及GA4+7 25 μM最佳，可使黃葉數降至2.3~2.5，消蕾率降至7.7%~11.9%外，並可使開花率達88.1%~92.3%，對提高貯後整體觀賞品質之效果最佳。故於長壽花的貯運使用上，可採用GA4+7 25 μM或Promalin 50 mg•L-1即可有效提高貯後品質。

The objectives of this study were to evaluate the effects of storage temperature and flowering stage on post storage quality of Kalanchoe blossfeldiana Pollen after simulated dark storage and causes of leaf chlorosis and flower abortioning after simulated dark storage. Subsequently, using antitranspirant or growth regulators to improve the poststorage quality. We defined three inch potted Kalanchoe with 0%, 10±5% and 35±5% flowering as stage 1, 2 and 3, respectively. Simulated dark storage of 5, 10 and 15℃ for 7 or 14 days were given to double Kalanchoe ‘Mona’. Leaf chlososis and flower abortion increased with lower temperature and extending duration. The quality of all stages were the best after 10℃ simulated dark storage for 7 days. Also, ‘Naomi’ at stage 2 or 3 and‘Gabrielle’, ‘Jodie’ and ‘Karen’ at stage 3 had the best poststorage quality after simulated dark storage. Thereby, 10℃ is the optimum storage temperature, and the period of simulated dark storage is 7 days at most. Plants with lower flower bud percentage more appropriate for low temperature dark storage, because five cutivars of Kalanchoe at stage 3 with high flowering percentage, can all reach 84.2% flowering rate after storage, and had less chlorosis and flower abortion. But at this stage, half of flowers had fully opened and some opened flowers began wilting and senescence, so postharvest longevity didn’t reach 6~8 weeks. However, plant at stage 1 or 2 had decreased flowering rate and increased abortion after storage, resulting in serious chlorosis ever with leaves dropping. Compare poststorage quality of ‘Mona’, ‘Naomi’, ‘Gabrielle’, ‘Karen’, and ‘Jodie’ after storage under 10℃, lower leaf chlorosis of ‘Mona’ is more serious than ‘Naomi’ and ‘Gabrielle’, which only partially chlorotic at leaf tip and ‘Jodie’ and ‘Karen’ did not chlorosis at all. ‘Mona’ is intolerant of dark storage due to the dramatic change of upper and lower leaf thickness and the leaves where thinner than other cultivar. ‘Mona’, ‘Gabrielle’, and ‘Naomi’ sprayed with ethephon 100 or 300 ppm lead to chlorosis and abortioing after dark storage. Among the five cutivars, ‘Mona’ is sensitive to ethylene and easily damaged, because it appears extremely chlorosis and abortioning ever with water-soak browning characteristic. Also ABA 25 μM induced the same symptom. Fumigating 1-MCP 0.2, 04, or 0.8 ppm and Fluridone 25 or 50 μM can delay quality descending. Although 1-MCP and Fluridone can delay chlorosis and abortion, post storage flowering percentage did not reach 60%. 1-MCP is more effective than Fluridone on both leaf chlorosis nad flower abortioning. Pretreatment spraying of antitransiprant 4 or 8 mg•L-1 increased stomatal resistance, but did not increase transpiration rate and can not retard the chlorosis of lower leaves and flower abortion. Treatment with BA 25, 50, 100 μM, GA3 100 μM, GA4+7 25, 50 μM or Promalin at 50, 100 mg•L-1 all decrease leaf chlorosis and flower abortion; combine of GA3 and BA with half of concentration (50 μM) is just as effectively as GA3 or BA alone at full concentration (100 μM) can decreased chlorosis from 16.5 to 2.8 and abortioning from 27.7% to 10.8%. Except 100 μM of GA3, 100 μM BA and 50 μM BA+50 μM GA3 induced flower malformation and incompletely explodding. Consequently diminishing BA concentration, the 25 μM or 50 μM of BA or GA4+7, and 50 or 100 mg•L-1 Promalin which is 1.8% gibberellin4+7 combination with 1.8% benzyladenine, all significantly decreased number of chlorotic leaves and make flowering over 75.9%. The poststorage quality of GA4+7 and Promalin treatment were the best among all growth regulators used. Therefore by using the GA4+7 25 μM or Promalin 50 mg•L-1 for improving the quality of Kalanchoe after simulated dark storage can promote ornamental value.