龍葵(Solanum nigrum L.)種子發芽能力之週年變遷

侯金日 顏照軒

國立嘉義大學 農藝學系

摘 要

本研究報告主要探討台灣旱田常見之雜草龍葵種子發芽能力之季節性的週年變遷。在嘉義地區採收之龍葵種子，埋於10公分深土中，每個月取樣，在室內四種不同溫度下和田間地表下0.3公分土中進行發芽試驗，凡兩年。掩埋試驗顯示，出土龍葵種子，在照光處理下除了掩埋初期發芽率不高（30-66%）外，在30/25、25/20、20/15和23/13℃下兩年皆有很高之發芽率。黑暗處理中掩埋初期之休眠期較長約3個月，之後發芽率提高，顯示無休眠狀態，在夏天高溫（30/25、25/20和23/13℃）發芽率下降（38-60%），則略顯出制約休眠現象。出土種子田間萌芽平均分佈於全年。每月種子季節性之自然萌芽集中於前三月。田間每月耕犁之試驗顯示龍葵種子全年皆可發芽。

關鍵詞：制約休眠、溫度、龍葵、發芽、種子

Seasonal Changes in the Germinability of Buried Seeds of Nightshade (Solanum nigrum L.)

Chin Jin Hou and Tauh-Shang Yen

Department of Agronomy, National Chiayi University,

Taiwan, R. O. C.

Abstract

The purpose of this report was to study the annual changes in the germinability of the buried seeds of nightshade grown in the dry farmland of Taiwan. The seeds were collected in Chiayi and buried in the upland soil of 10 cm in depth and exhumed monthly, for up to two years. The exhumed seeds were then tested for germination under four different temperature regimes or field soil of 0.3 cm in depth. The germination of buried seeds incubated at 30/25, 25/20, 20/15, and 23/13℃ in light was high except short treatment of seed buried being 33-66% of seed germination. The seed buried in dark condition more than three months that appeared high germination, therefore the seed of nightshade exhibited an annual non-dormancy. However, these buried seeds incubated at 30/25, 25/20 and 23/13℃ in summer were low germination（38-60%）. This result is conjectured that the seed of nightshade exhibited a conditional dormancy. The emergent rates of exhumed seed were not different among seed sowed monthly. Two years measurement of nightshade seed emergence showed that the buried seeds mostly germinated at the beginning of three months after the burial treatment. These results of monthly plowing experiment indicated nightshade seed could germinate all year round.

Key words：conditional dormancy , temperature, nightshade, Solanum nigrum L., germination, seed.