栽培密度對玉米生育及產量之影響Ⅰ.營養生長期

The Effects of Planting Density on the Growth and Yield of Corn Ⅰ. Vegetative Growth Phase

魏夢麗(Meng-Li Wei) ； 陳烈夫(Lit-Fu Chan) ； 姜義展(Yih-Jan Jiang) ； 劉大江(Dah-Jiang Liu)

《中華農業研究》 44卷1期 (1995/03) Pp. 26-36

https://doi.org/10.29951/JARC.199503.0004

摘要

玉米吐絲前的營養生長可能影響子粒產量表現，本試驗以玉米品種臺農一號為材料，調查營養生長期問植株物質與氮素的累積與分配性狀，同時探討栽培密度的作用，以對其產量生理有進一步的瞭解。於1991及1992年秋作進行試驗，行距均為75cm, 1991年採用株距11、22及44cm三種處理，1992年採用11與22cm兩種株距，又於雄穗分化始期將部份植株株距自11cm問拔為22cm；在播種至吐絲期間連續取樣，分析不同器官之乾物質與氮素累積性狀。自第十二葉齡以後，栽培密度對臺農一號單株乾物質及氮素累積能力的影響方較明顯，葉片乾物質與氮素含量佔全株總量的比值快速下降，而莖稈乾物質與氮素含量佔全株總量的比值相對快速升高。玉米植株在第十二葉期至吐絲期約一個月生育期間，具有極旺盛的同化作用，植株所累積的乾物質量佔吐絲期總乾物量的80~92%，所累積的氮素量佔吐絲期總含氮量的69~85%，於密度處理間比較，則以最密植處理之比值較低。玉米植株自播種至吐絲期，生長速率持續上升，尤以吐絲前約二週之速率最高，乾物質累積速率最高可達389kg/ha.day，氮素累積速率最高達6.4kg/ha,day，隨株距之增加而顯著降低。在營養生長全期，乾物質累積速率與氮素累積速率的比值有逐漸上升的趨勢，但在栽培密度處理間則多無顯著差異，顯示以單位氦素為基準的乾物質累積速率，在不同生育階段雖然有異，但在本試驗栽培密度條件下，並不受環境因子的環境。

關鍵字

玉米 ； 栽培密度 ； 營養生長 ； 乾物質累積 ； 氮素累積

並列摘要

Information pertaining to the growth characteristics of corn during vegetative growth is limited. The purpose of this experiment was to investigate the patterm of dry matter and N accumulation of corn hybrid Tainung 1 from sowing to silking and to study their responses to plant spacing treatments. Field experiments were conducted in the fall crops of 1991 and 1992 with a row spacing of 75cm. Within-row spacings were 11, 22, or 44cm in 1991, and 11 or 22cm in 1992. In 1992, the spacing was altered from 11cm to 22cm in part of the plots by thinning the stand at tassel initiation. The effects of plant spacing on dry matter and N accumulation were not significant until the 12th leaf stage. From the 12th leaf stage to silking, the proportion of dry matter and N accumulated by the leaf blade decreased while that by the stalk showed an increasing trend. During this period, the amounts of dry matter and N accumulation by the plants accounted for 80~92% and 69~85%, respectively, of the accumulation at silking stage. Dense planting resulted in lower ratios as compared to other treatments. The growth rate increased continuously and peaked as the plants approached silking. The highest accumulation rates were 389 kg/ha. day for dry matter and 6.4kg/ha. day for N, and decreased with decreasing population density. During the entire vegetative growth phase, the ratio of dry matter accumulation rate to N accumulation rate increased continuously, however, no significant difference was recorded among plant spacing treatments. This indicate that the amount of dry matter accumulated per unit of tissue N was different according to developmental stage but was less affected by environmental factors.

並列關鍵字

Zea mays ； plant spacing ； vegetative growth ； dry matter accumulation ； N accumulation