施钾方式对春玉米根系特征的影响

以金山27为供试品种,在150和300 kg/hm2两个施钾水平(K2O)下,研究施钾方式(一次性施入和钾肥后移)对春玉米根系特征的影响。结果表明,不同施钾水平下,根系干重随施钾量增加而增加,尤以吐丝后0~20 cm土层增加明显;同一施钾水平下,各生育时期0~40 cm土层均表现为钾肥后移方式根系干重减小。不同施钾水平下,0~20 cm土层根干重占总干重比例各生育时期均随钾肥用量增加而下降,21~60 cm土层根干重占总干重比例减小,尤以乳熟期更为明显;同一施钾水平下,钾肥后移方式0~20 cm土层根干重占总干重比例增加。不同施钾水平下,各土层根条数、最大根幅随施钾量的增加而增加,最大根幅下移;同一施钾水平下,钾肥后移方式最大根幅、根条数及最大根幅深度均减少,且随土层深度增加差异增大。

Effects of Potassium Fertilization Methods on Root Characteristics of Spring Maize

Jinshan27 was used as the test material to study the effects of different potassium levels(K₂O 0, 150 and 300 kg/ha) and application methods(all the basic fertilizer and postponing potassium application) on the root characteristics of spring maize. The results showed that under different k levels, root dry weight increased with the increase of the amount of k, especially in 0-20 cm before siking. Under the same level of k application, the root weight at 0-40 cm soil layer decreased with postponing potassium. Under different k levels, the percentage of root weight at 0-20 cm soil layer was lower with increase of k application in each growth period. The percentage of root weight at 21-60 cm was contrary, especially in the milking stage. Under the same level of k, the percentage of root weight at 0-20 cm soil layer was increase with postponing potassium. Under different k levels, each soil root number, the biggest root width increased with the increase of k application, the biggest roots width tended to be deeper. Under the same level of k, each soil root number, the biggest root width increased were decreased with postponing potassium, and the differences increased with the soil depth increased.