- 期刊
利用根箱探討水稻根系生長之變化
Study on Root System of Rice by Root-Box Method
摘要
根系生長在土壤中，研究相對困難，相關測量方法也不盡相同，本試驗所利用的根箱是由5個獨立直式根槽（a，b，c，d，e根槽）和鋼提架所組合而成，材質不鏽鋼，根箱的長×寬×高為40×40×30公分，根槽的長×寬×高為40×8×30公分。每期作插秧前，將根箱埋入田間，並依分蘗盛期、抽穗期及乳熟期分別從土中取出根箱進行洗根作業並調查根系長度與乾重於土壤中之分布情形。水稻第二期作分蘗盛期、抽穗期及乳熟期的最高根乾重分別為0.10公克、0.30公克、0.16公克，第一期作的最高根乾重則分別為0.16公克、0.24公克、0.68公克，第2期作的最高根長分別為290公分、920公分、760公分，第1期作的最高根長則分別為320公分、350公分、1060公分，主要都集中於稻株附近的土塊單位，即在中間根槽（c槽）的位置範圍。觀察各時期根箱內不定根分布情形，分蘗盛期田間進行排水作業，因土壤乾燥可促進根系向下生長，有助於水稻後期養分吸收及抗倒伏之效果。抽穗時期根量明顯增加，且根箱中間c槽兩側的b、d槽分布之寬度及深度都有很密集的根量存在，呈現擴大範圍斜向生長，根系發展逐漸穩定。乳熟時期大多為細小之不定根，在根長分布上可以顯現出來，但在其根乾重分布上則無法測出其單位重量，可能稻根正逐漸萎凋。根箱內整體根系隨著不同生育時期主要呈現輻射狀向下生長。
並列摘要
It is hard to study about root development cause to grow in the soil. Besides, the measured methods have not been established. The root-box are made by steel, there are five straightly frame and barrow frame. The length × width × height of root-box is 40×40×30 cm, and the root frames sizes are 40×8×30 cm. The root-box buried into field in each crop season, then taken out root-box in tilling stage、heading stage and milky stage to examine rice roots. The highest root dry weight of second crop season in tilling stage、heading stage and milky stage are 0.10g、0.30g、0.16g. The highest root dry weight of first crop season in tilling stage、heading stage and milky stage are 0.16g、0.24g、0.68g. The highest root length of second crop season in tilling stage、heading stage and milky stage are 290cm、920cm、760cm. The highest root length of first crop season in tilling stage、heading stage and milky stage are 320cm、350cm、1060cm. They are mainly focused on the clods unit of rice vicinity, was c frame. The distributions of adventitious roots were observed during different stage in root box. The water drained in field during tilling stage can make root grow downward to help rice to absorption nutrient and non-lodging. The root increase width and deep in b、d frame during heading stage, that was developed stable. There are many little adventitious roots during milky stage, that root length can be emerged but root dry weight can not be measured, that may be rice root gradually wilt. Root system is mainly characterized by radial growth direction in different growth stage. This study was aimed at using root-box to explore root system with a view to provide an important tool for research.