斯里兰卡的柽麻生长规律及水肥条件对产量的影响

本文是笔者在斯里兰卡连续五次种植柽麻的研究结果。结果表明,柽麻在苗高18厘米时是生长速度的转折点,在此之前是幼苗缓慢生长期,在此之后生长速度增加2—4倍,至初花期生长速度又明显减慢,生长曲线呈S形。因柽麻无论何时播种,从出苗至开花的总天数比较相近,所以缩短幼苗缓慢生长期是获得柽麻高产的关键。采取科学的水肥管理是缩短幼苗缓慢生长期的有效途径。 试验表明,出苗期、生长前期和开花期的适宜土壤含水量分别为不低于田间持水量的60％、40％和50％。在苗期施用磷肥和少量氮肥可促进幼苗生长。因此,只要在出苗后及时地加强水肥管理,就能确保柽麻的高产。

THE GROWING REGULARITY OF SUNN HEMP AND THE EFFECT OF THE CONDITION OF SOIL MOISTURE AND FERTILIZER ON ITS YIELD IN SRI LANKA

The results of planting sunn hemp five times on end show that the growing regularity of sunn hemp is the slow growth rate in seedling stage. The turning point in growth rate is at the seedling height of 18em. After that its growth rate increases 2 to 4 times. The total growth days of sunn hemp from the emergence of seedlings to first flowering are almost the same, so shortening the seedling slow growth stage is a key measure to get high yield of sunn hemp. Adopting scientific management of soil moisture and fertilizer is an available way to shorten the seedling slow growth stage.Experimental results indicate that suitable soil moisture content in the stage of emergence, early stage of growth and flowering stage is respectively not less than 60%, 40%, and 50% of field moisture capacity. Dressing phosphorus and a small amount of nitrogen can promote the seedling growth. Thus, with timely scientific management of soil moisture and fertilizer in seedling stage, high yield can be ensured.