硬水抑制一品红生长的主因子初探

A Preliminary Study on the Major Inhibitive Factor of Hard Water on Growth of Poinsettia

硬水显著抑制一品红生长。开花时浇硬水的植株株高、枝长、花径、冠幅显著小于浇反渗纯净水的植株，两者基质的pH值相似（硬水、纯水分别为7．16、7．11），但是电导率差异显著（硬水、纯水分别为2．2、1．1ms／cm）。基质起始pH值显著影响盆栽基质的pH值和一品红生长，在5．1～5．8范围内随着基质起始pH值的升高一品红生长量增加，基质pH值也增加到5．6～6．7。水源pH值调整对盆栽基质的pH值和一品红生长也有影响，但是幅度较小。初步推断，硬水主要通过盐分积累抑制一品红生长。

Hard water inhibited significantly the growth of poinsettia. The plants irrigated with hard water were shorter and smaller with shorter shoots and smaller bloom size than those irrigated with reverse osmosis purified water. Substrates irrigated with hard water showed higher EC than that irrigated with pure water, and the pH values were similar. Initial pH of substrate affected significantly root zone pH and growth of poinsettia. Among the range of 5. 1 ~ 5.8, poinsettia growth increased with initial pH of substrate and the substrate pH increased to 5.6~6.7. pH adjustment of irrigation water also affected root zone pH and the growth of poinsettia, but in a less extent. As a conclusion, salt accumulation around the root zone may be the major factor that hard water inhibited the growth of poinsettia.