硝酸钾和硫酸钾对番茄幼苗生长、根系形态及钾素吸收和生理利用效率的影响

采用水培试验,研究不同钾肥种类(KNO3、K2SO4)、不同钾素水平(0、2.0、4.0和8.0mmol/L)对"天福冠露"和"毛粉802"2个番茄品种幼苗生长、根系特征及对钾素吸收、生理利用效率的影响。结果表明,随钾素水平提高,番茄鲜重、干重以及根长、根体积、根直径等根系特征显著提高。在钾素水平为4.0、8.0mmol/L时,硝酸钾处理的番茄株高、根长显著高于硫酸钾。钾素水平为8.0mmol/L时,硫酸钾根直径显著高于硝酸钾处理的;"天福冠露"施用硝酸钾的根尖数显著高于施用硫酸钾;"毛粉802"施用硫酸钾,植株的根直径、钾含量和钾素积累量显著高于硝酸钾处理。番茄水培适宜的钾素浓度为8.0mmol/L,硝酸钾有利于番茄生长发育,硫酸钾有利于番茄对钾素的吸收。在相同钾素水平条件下,2个番茄品种鲜重、干重均无显著差异。

EFFECT OF POTASSIUM NITRATE AND SULPHATE ON GROWTH ,ROOT MORPHOLOGICAL TRAITS ,POTASSIUM UPTAKE AND UTILIZATION EFFICIENCY OF TOMATO SEEDLINGS

Water culture experiments were conducted to investigate effect of potassium on seedling growth,root morphology traits and potassium uptake and physiological K use efficiency with different potash(KNO3,K2SO4),different K levels(0.0 mmol/L,2.0 mmol/L,4.0 mmol/L and 8.0 mmol/L) and two varieties("TFGL","MF802").After treated with the levels of 4.0 mmol/L and 8.0 mmol/L,root length and plant height of tomato plants were significantly higher than that treated with potassium sulphate.At the level of 8.0mmol/L,the number of tomato root tips with potassium nitrate was significantly higher than that with potassium sulphate in "TFGL".K content and the root diameter of plants treated with potassium sulphate was significantly higher than treatments with potassium nitrate in "MF802".Results showed that potassium treatment with 8.0mmol/L was the most suitable for tomatoes.Potassium nitrate is beneficial to the growth and development of tomato,and potassium sulfate is sensitive to potassium absorption.Under the treatment with the same potassium level,no significant difference was found in the fresh weight and dry weight of two different tomato varieties.