非洲鳳仙花、黃帝菊、百日草種子浸泡矮化劑Paclobutrazol、Uniconazole對其發芽及穴盤苗品質的影響

Germination, Plug Quality and Subsequent Growth of Impatiens, Melampodium and in Response to Seed Treatment with Paclobutrazol or Uniconazole

張祿堂(Lu-Tang Chang)

指導教授 ： 李哖

國立臺灣大學/生物資源暨農學院/園藝學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.02454

摘要

此研究以矮化劑paclobutrazol或uniconazole處理非洲鳳仙花’Accent Coral’、皇帝菊’Derby’、百日草’Profusion White’種子，可有效控制下胚軸及第1~3節間長度。二種類矮化劑比較之，uniconazole較paclobutrazol具有較強的控制效果。濃度增加效果遞增有限，且依作物種類不同反應不一。而種子浸泡uniconazole 處理能明顯控制植株高度，尤其當對照組在四週後(非洲鳳仙花) 、二週後(黃帝菊)株高快速增加，uniconazole仍然可有效控制株高。但是以不同濃度測試，顯示uniconazole 5 mg•L-1即有不錯的控制效果，而百日草因生長勢較強需處理uniconazole 20 mg•L-1才能有較佳的控制效果。種子浸泡paclobutrazol處理在穴盤苗生產過程中的五週內，均較對照組明顯的抑制植株高度。隨著濃度的增加，在前四週的株高並沒有顯著的差異。非洲鳳仙花、皇帝菊在第四周後，不同濃度處理間產生顯著性差異，此差異可能顯現出paclobutrazol的抑制效果已有減弱的趨勢。將穴盤苗移植至11cm盆6週後非洲鳳仙花、黃帝菊種子浸泡15或30 mg•L-1 uniconazole的處理，其植株仍有矮化的生長表現。
比較噴施paclobutrazol處理與種子處理paclobutrazol或uniconazole對於控制非洲鳳仙花穴盤苗株高的效果差異。在播種後5週，種子處理250 mg•L-1 paclobutrazol或5 mg•L-1 uniconazole相較於對照組，可分別減少穴盤苗株高55%及69%。在子葉展開後噴施paclobutrazol 5 mg•L-1則減少穴盤苗株高35%。在移植11cm盆6週後種子處理250 mg•L-1 paclobutrazol或5 mg•L-1 uniconazole仍可分別減少植株高度8%及22%，且不影響開花日數。
因此建議非洲鳳仙花種子可處理uniconazole 5 mg•L-1 或paclobutrazol 250 mg•L-1 12小時、黃帝菊種子處理paclobutrazol 250 mg•L-1或uniconazole 5 mg•L-1 8小時、百日草種子處理uniconazole 20 mg•L-1 8小時可在不降低發芽率的情況下，有效控制穴盤苗的生長。

關鍵字

種子處理 ； 生長抑制劑 ； 花壇植物

並列摘要

Height control is particularly important to produce the high quality seedlings of bedding plants in Taiwan, where environmental control is more costly for regulating plant height. Retardant application as spray is used commonly in commercial practice but non-uniform plant size can result from non-uniform application. The objectives of the thesis were to compare germination performance, seedling growth for three bedding plant species (impatiens, melampodium, zinnia) after soaking seeds in paclobutrazol or uniconazole.
Paclobutrazol at 250 to 200 mg•L-1 did not affect the germination percentage of impatiens while uniconazole treatment at 15, 30 mg•L-1 reduced the germination percentage for 95.2 and 92.5%. Seeds of melampodium presoaked with uniconazole at 15, 30 mg•L-1 for 12 hours would strongly affect seed germination, increasing paclobutrazol from 250 to 2000 mg•L-1 had no significant effect on final germination percentage, T0, T50, T90 and T90-T10 though germination percentage decreased slightly at higher concentration (1000 and 2000 mg•L-1). The effect of uniconazole on zinnia seeds was not significant in T0 and T50, yet it did have increased T90 for 2.3 days at higher concentration (20 mg•L-1). Soaking seeds of impatiens in 5 or 15 mg•L-1 uniconazole for 12 hours rather than 4 hours decreased germination percentage and increased T0, T50 and T90. Seeds of impatiens presoaked with uniconazole for 4 hours at different timescale during imbibition process on germination performance of impatiens ‘Accent Coral’. Germination percentage and T90-10 were not affected by the treatment while the T90 significantly increased by 1~1.3 days. Increasing uniconazole volume during 12-h soak had no effect on total germination percentage, although T0, T50 and T90 increased.
Seeds of ‘Accent Coral’ impatiens were soaked for 12 hours with various paclobutrazol or uniconazole. Seeds of ‘Derby’ melampodium and ‘Profusion White’ zinnia were soaked for 8 hours with various paclobutrazol or uniconazole. After the seed treatment, seeds were dried for 24 hours prior to sowing in 288plug tray. For the three species, plants were smaller the higher the concentration of the triazole-type retardant, and the efficacy of uniconazole at lower concentration was greater than that of paclobutrazol at higher concentration. At 11 weeks after sowing, excessive dwarfing occurred in impatiens that received from 15 to 10 mg•L-1 uniconazole. The single- spray of paclobutrazol compared the effect of seed treatment with paclobutrazol or uniconazole on growth of 288plugs impatiens ‘Accent Coral’. Soaking seeds with 5 mg•L-1 uniconazole or 250 mg•L-1 paclobutrazol resulted in 69% or 55% shorter seedling height, respectively, than those of nontreated plants at 5 weeks after sowing. Shoot application 5 mg•L-1 paclobutrazol reduced plant height by 35%. Soaking impatiens seeds with 250 mg•L-1 paclobutrazol or 5 mg•L-1 uniconazole resulted in plant height reduction by 8% and 22% 11 weeks after sowing, respectively.
These results indicate that retardants application to seeds may reasonably using a 12 hour soak in 250 mg•L-1 paclobutrazol or 5 mg•L-1 uniconazole for impatiens, 8 hour soak in 250 mg•L-1 paclobutrazol or 5 mg•L-1 uniconazole for melampodium and 8 hour soak in 20 mg•L-1 uniconazole for zinnia.

並列關鍵字

seed pretreatment ； growth retardant ； bedding plants

參考文獻

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