不同施硼量对油菜叶片中不同形态硼含量的影响

Response of different B fractions in rape leaves to the amount of boron fertilizer

采用盆栽试验研究了不同施硼量对不同生育期不同部位叶片中水溶性硼和全硼含量的影响,并对以水溶性硼代替全硼作为植株营养诊断的方法进行了初步探讨。当施硼量达到5 1kg/hm2,油菜苗期、抽薹期的生物产量以及子粒产量均下降,但叶片中的全硼和水溶性硼含量仍随施硼量的增加而增加。不同生育期和不同部位叶片的全硼含量虽然与施硼量有较好的相关性,但是不同处理之间的差异,特别是过量差异过小,很难用于营养诊断。水溶性硼含量与施硼量也有较好的相关性,而且苗期未完全展开叶片和完全展开叶片的水溶性硼含量可以较敏感地反应油菜的硼营养差异,因此,可以用作硼的营养诊断方法,但是水溶性硼的诊断临界指标需要进一步的研究。

Pot trials were conducted to study the response of different fraction of B in rape leaves to different B fertilizer application levels in different growth stage and different position, and the possibility of using water extractable B in rape leaves as the diagnostic criterion was discussed.When B application level was higher than 5.1 kg/hm^2, both the biomass of rapes in seedling stage and shooting stage and the grain yield decreased, but the total B content and water extractable B content in leaves increased with the enhance of B application levels. Although there were good relationship between total B contents and B fertilizer application levels, the differences of total B contents among B fertilizer treatments were too narrow to be used as diagnoses;Good relationships was also appeared between water extractable B content in leaves and B fertilizer treatments, and the water extractable B content in both quickly-spreading leaves and well-spread leaves in seedling stage were sensitive to the B nutrient status, thus there was possibility to use water extractable B as the diagnostic criterion of B nutrition of rapes. But further research was needed for the setup of water extractable B level in leaves as the diagnosis criterion.