不同供锌水平对苹果幼树干物质和锌积累及分配的影响

采用盆栽砂培试验,研究了低、中、高3个供锌水平(Zn 0.013、0.254和5.070 mg/L)对苹果幼树干物质和锌积累、分配动态的影响。结果表明,锌的过量及缺乏均对果树的生长及养分吸收产生影响。生长初期,苹果幼树根系活动较晚,枝叶的快速生长主要利用根茎中的养分,锌的积累量呈快速增加趋势,处理间差异显著;低锌处理,除根系明显增加外,其他器官变化较小,根系的锌分配比例明显高于中锌、高锌处理。说明生长后期,低锌、高锌抑制了树体的生长,且低锌处理的树体锌主要分布于地下,上运明显受阻;而中锌、高锌处理,地上部锌含量要高于根系。

Effects of zinc fertilization on the dynamics accumulation and distribution of dry matter and zinc in apple trees

A sand culture experiment was conducted to study the dynamic accumulation and distribution of dry matter and zinc in organs of apple trees under three zinc application levels, Zn 0.013, 0.254 and 5.07 mg/L. The results show that the growth and nutrient uptakes of apple trees are affected under both the deficiency and excess of Zn supplies. There are little effects on the accumulation and distribution of dry matter and nutrient under different zinc levels at the early growth stage, and the nutrients in roots and stems are utilized by branches and leaves for quickly growth. With the plant growth, the first peak of new roots turns up, the dry matter is accumulated quickly under different treatments, while the growth of roots is constrained by the deficiency and excess zinc supplies, and the zinc contents in each organs are significantly increased except branches and the order is Zn3 > Zn2 > Zn1. The dry matter accumulation is constrained by the deficiency and excess zinc supplies at the later growth stage, and zinc toxicity is happened under the excess zinc supply. The accumulation of zinc is increased quickly under the moderate and excess zinc supplies, however, the roots are increased under the deficiency treatment, and the distribution rate in root is significantly higher than that under the moderate and excess zinc supplies. These results indicates that at the later growth stage, the plant growth is constrained by the deficiency and excess zinc supplies; distribution rate of zinc in roots is higher than that in shoots under the lower zinc treatment, while the content of zinc in shoots is higher than that in roots under the moderate and excess zinc treatments.