包心芥菜及油菜心種子休眠性及打破休眠方法之研究

Studies on the Seed Dormancy and its Breaking Method for Heading Mustard and Late Edible Rape

一、包心芥菜種子有顯著之休眠性，休眠期間在二個月以內。激勃索、硫脲及激勃素與硫脲之等量混合液，對於打破休眠有效果。低溫處理對於打破休眠有效果。藥劑與低溫處理併用時，對於打破休眠之效果，比藥劑或低溫單獨處理時為高。激勃索及硝酸鉀對於種子發芽完全正常，且有促進幼莖伸長作用，硫脲對種子發芽易引起藥害。二、晚生油菜心種子有顯著休眠性，休眠期間約在二個月以內。打破休眠以激勃索、硫脲及激勃素加硫脲混合液效果較佳，硝酸鉀對晚生油菜心種子無打破休眠效果。低溫處理打破休眠之效果較藥劑處理為大，低溫處理與藥劑併用可以完全打破休眠。藥害情形與包心芥菜相似。

1. The purpose of this study is : (1) to detect the dormant characters of the seeds of Heading Mustard and Late Yu-Tsai-Hsin (Brassica chinensis), the length of dormant period are also investigated, (2) to compare the efficiency of Gibberellin, Thiourea, Potassium nitrate, which treated the seeds with each only, and then treated with a mixture of Gibberellin and Thiourea as well as treated with chemicals and prechilling (5 C for 5 days), in order to understand the effect of breaking the dormancy of seeds and elevate the germination percentage. 2. Heading Mustard: (1) The dormant character of Heading Mustard seed was significant,and its dormant period within two l}lOnths. (2) The effect of Gibberellin, Thiourea and Mixture of Gibberellin and Thiourea treatment on breaking the dormant seed was apparent, and potas­sium nitrate was no significant. (3) Treated the seed with prechilling under 5°C for 5 days, it has been shown the effect on breaking the dormancy. (4) Treated with the chemicair in available concentration and with prechilting, the effect on breaking the dormancy of seed was most significant. 3. Late Edible Rape (Yu-Tsia-Hsin): (1) The dormant character of Late Yu-Tsai-Hsin was significant and it's dormant period within two months. (2) The effect of Gibberellin, Thiourea and mixture of Gibberellin and Thiourea treatment on breaking the dormant seed was more significant, and potassium nitrate was no significant. (3) Treated the seed with prechilling under 5° C for 5 days, it has been shown the more effect on breaking the dormancy than with chemicals. (4) Treated with chemicals and prechilling. the effect on breaking the dormancy of seed was perfect.