Growth and Yield Respones of Maize (Zea mays L.) to Soil Water Deficits. Ⅱ. Effects of Water Deficit Timing and Strength

玉米(Zea mays L.)生長與產量對土壤缺水之反應（二）缺水時期及缺水程度之影響

楊純明(Chwen-Ming Yang) ； 范明仁(Ming-Jen Fan) ； 向為民(Wei-Min Hsiang)

《中華農業研究》 42卷2期 (1993/06) Pp. 173-186

https://doi.org/10.29951/JARC.199306.0008

摘要

水分為本省玉米生產之一項主要限制因子，因此殊有必要詳加探討各局地環境下玉米生長與產量和土壤水分之關係。本文研究係以玉米單交品種臺農一號為材料，在臺灣省農業試驗所農場進行田間試驗，評估玉米缺水時期及土壤缺水程度對玉米生產之影響。土壤缺水採人工斷水達成，即在自然狀況下實施停止灌水方式達到預先設定之土壤水分含量，土壤水分潛勢範圍介於－1/3（對照組）至－10bars之間。1991年秋作完成生殖生長期缺水處理，而在1992年則完成營養生長期缺水處理。根據試驗結果，玉米每株葉片數不因土壤缺水改變，而當土壤水分潛勢下降至－5bars（秋作）及－8bars（春作）時，葉面積明顯減少。營養生長時期13天斷水至－8bars時，影響玉米植株高度（於50%雌穗吐絲期測量），惟並未顯著延長或縮短雄穗開花及雌穗吐絲日期。生殖生長時期斷水達－5bars時，將造成植株乾重減少10%以上。每公頃穗重及籽粒產量在兩期作均因土壤缺水而降低，秋作在－10bars、春作在－8bars下，籽粒產量分別僅及對照區者之60及80%。本文結果亦發現，在試驗之缺水範圍內，土壤水分潛勢與玉米籽粒產量間呈現顯著直線相關，產量隨土壤水分潛勢下降而降低。

關鍵字

生長 ； 產量 ； 玉米 ； 土壤缺水 ； 缺水時期 ； 缺水程度

並列摘要

Water is a major limiting factor on maize production in Taiwan. It is very important, therefore, to study the relations of soil moisture stress and maize (Zea mays L.) yield under local conditions. This field work was conducted on the experimental farm of Taiwan Agricultural Research Insitiute (TARI) at Wufeng, Taiwan to evaluate the relative effects of water deficit timing and strength on the growth and yield of maize, cultivar Tainung No. 1. Water stress was imposed by the withholding of irrigation during reproductive growth phase (fall crop 1991) and vegtative growth phase (spring crop 1992), respectively, to cause soil water potentials to the range from -1/3 (control) to -10 bars. It was shown that leaf number per plant was not significantly affected by water stress in both seasons, whereas leaf area per plant was reduced when soil water potential lowered to-5 bars in the fall crop of 1991 and -8 bars in the spring crop of 1992. As indicated by plant height measured at the 50% silking, a 13-day period of water deficit to -8 bars in the vegetative growth phase of spring crop influenced plant growth in the long run. The heading and the silking dates were not dramatically changed by water deficits in both crops. But more than 10% reduction of plant weight was recorded as soil water potential decreased to below -5 bars in the reproductive phase. Ear weight and kernel yield were decreased by water stress below -2.5 bars in both crop seasons. Kernel yield was reduced to 60 and 80% of the control at -10 and -8 bars in fall crop and spring crop, respectively, which mainly associated with a lower kernel weight. It is suggested that soil water potential can be employed on predicting maize production by water deficit and kernel yield reduction depends on severity of soil water stress.

並列關鍵字

Growth ； Maize ； Soil water deficit ； Strength ； Timing ； Yieid