洋桔梗苗期溫度與植物生長調節劑對生育之影響

Abstract

本試驗使用洋桔梗 ''Royal White''(極早生種), ''Azuma no Nami''(早生 種), ''King of Blue''、''King of Pink Picotee''(中早生種),''Romio'' (中生種)和''紫苑''(中生種) 6個品種為材料,探討苗期施用Ethrel、ABA (Abscisic acid (±)cis - trans isomer)、矮化劑、夜間涼溫處理 (15C),及播種後高溫處理(33/28c)對生長與開花之影響。洋桔梗苗期施用 Ethrel會抑制''Royal White''、''King of Blue'' 和 ''紫苑''品種初期的生 長,且施用濃度愈高抑制作用愈強。而施用Ethrel 200ppm以上只會降低'' 紫苑''品種的抽苔率,對其他品種則不影響。施用Ethrel也會延後開花和增 加著花節位,且濃度愈高愈晚開花。''Royal White'' 品種以 Ethrel 200ppm 處理株高最高; ''King of Blue'' 品種則以Ethrel 400ppm株高最 高。施用ABA 300 和600ppm對抑制初期生長的作用不明顯,也不會降低抽 苔率。苗期施用矮化劑可抑制初期的抽苔,且以Sumi-7 20ppm 和 PP333 200ppm效果較持久。施用Sumi-7 20ppm會降低''Royal White''品種抽苔率; 而 B-9 5000ppm、Sumi-7 20ppm、A-Rest 50ppm和 PP333 200ppm 都會降 低''紫苑''品種之抽苔率。''Royal White''品種施用Sumi-7 20ppm 和PP333 50ppm會延後開花。而施用B-9 5000ppm;Sumi-7 5、20ppm;PP333 50、200 ppm 和 A-Rest 10ppm皆會延遲''紫苑''品種開花。''Royal White''品種施用 Sumi-7 5和20ppm反而可增加株高;而B-9 2000ppm和Sumi-7 5ppm也增加'' 紫苑''品種之株高。Sumi-7 5,20ppm和 PP333 50,200ppm會提高''紫苑''品 種之著花節位。苗期隨著涼溫(15C)處理的期間愈長愈慢開花, 且著花節 位愈高; 但節間縮短。夜間涼溫處理4週可使''Azuma no Nami''品種二個月 苗達最大株高,而三個月苗則以夜間涼溫處理2或4週最高。''Romio''品種二 個月苗以夜間涼溫處理6週最高；而三個月苗則以2和4週最高。於十月底 播種後予以高溫(33/28C)處理1-7週的植株,經冬季的低溫可打破簇生化。 雖然比對照組慢抽苔和開花,但較為整齊且抽苔節位和側枝數增加而株高 、著花節位和鮮重皆與對照組無顯著差異。

The growth activities of ''Royal White'',''King of Blue''and ''Si En'' in the early stage were inhibited by spraying Ethrel.This inhibitory effect increased when higher concentrations were applied. There was no difference in the bolting percentage of the cultivars except ''Si En'' by using Ethrel at more than 200ppm.It increased the node to the first flower but delayed flower.As the concentrations of Ethrel increased, the days to flower increased.The highest stem length of ''Royal White'' was at Ethrel 200 and 400ppm for ''King of Blue''.ABA 300 and 600ppm treatments did not reduce the early activity and bolting percentage.The effects of Sumi-7 20ppm and PP333 200ppm were constant. Sumi-7 20ppm application to ''Royal White''and B-9 5000ppm Sumi-7 20ppm, A-Rest 50ppm and PP333 200ppm to ''Si En'' decreased the bolting percentage. Treated ''Royal White''with Sumi-7 20ppm, PP333 50ppm, and ''Si En'' with B-9 5000ppm, Sumi-7 5 20ppm A-Rest 10 ppm and PP333 50, 200ppm delayed the flowering. The longer the cool night temperature treated during the seedling stage, the later the flowered. It also had the higher number of the first node to flower but shortened the internode.The highest stem lengths of the 2-month-old seedlings of ''Azuma no Nami'' were treated with 4 weeks cool night temperature,and the 3-month-old seedlings were 2 to 4 weeks. The highest stem length of the 2-month-old seedlings of ''Romio'' were treated with 6 weeks cool nigh temperature and the 3-month- old seedlings were 2 to 4 weeks. It could break rosette completely by cool temperature from November to March if the plants sown in the late October and treated with 1-7 weeks high temperature(33/28C). It bolted and flowered uniformly although later than the control. It also had higher number of node to bolting and branches. There was no significant difference in height, nodes to the first flower and the fresh weight.