缓释肥不同施用深度对木薯生长的影响

Effects of fertilization depth of slow-release fertilizer on cassava growth

以‘南植199’为试验材料,选择8、10、15、20 cm 4个不同的施肥深度(种茎的种植深度与施肥深度相同),施用单膜小颗粒缓释肥(C1)和双膜小颗粒缓释肥(C2),以不施肥(C0)为对照,设置C0-8、C1-8、C1-10、C1-15、C1-20、C2-8、C2-10、C2-15等8个处理,通过测定木薯的农艺性状、产量、结薯深度、半幅宽以及肥料利用率,比较2种缓释肥不同施肥深度对木薯生长的影响。结果表明:在C1和C2肥料下,施肥深度15 cm处理的出苗率最高,分别比同种肥料施肥深度8 cm处理的高13.2%、18.0%;在块根形成期(植后79 d)和收获期,C1-15的株高显著高于C2-15的;收获期C1-8的茎粗显著大于C2-8的,C1-10的显著大于C2-10的;C1-10和C2-10的单薯质量、鲜薯产量、淀粉产量、淀粉含量分别为C1、C2肥料下的最高值,C1-10的鲜薯或淀粉产量比C1-8的增产约10%,C2-10比C2-8仅略有增产,差异均不显著;8个处理中,C1-20的氮肥利用率(40.6%)最高,C2-8的磷肥利用率(43.8%)最高,C1-10的钾肥利用率(59.4%)最高。综合分析比较,C1-10为本试验最优处理,推荐在木薯机械化作业时采用8~10 cm的种植深度和施肥深度,如遇干旱天气可适当增加播种深度。

To study effects of fertilization depth of two slow-release fertilizers and cassava stem depth on the growth on the cassava variety NZ199,we set up 8 treatments,including two slow-release fertilizers(single-film small granules C1 and double-film small granules C2),four fertilization depths and cassava stem depths(the traditional cultivation with about 8 cm and the tested 10,15,20 cm,labelled as CK-8、C1-8、C2-8 etc).Agronomic traits,fresh root yield,tuberous depth,half width of cassava and fertilizer utilization rate were collected to index the growth.The results showed that the germination rate of two fertilizers with 15 cm depth were the highest,which were13.2%and 18.0%higher than 8 cm depth on the same fertilizers.At the root formation stage(after planted 79 d)and harvest stage,the plant height of C1-15 was significantly higher than that of C2-15,and stem diameter of C1-8 was significantly higher than that C2-8 at harvest stage,and C1-10 was significantly higher than that of C2-10.The single root weights,fresh root yields,starch yields and starch contents of C1-10 and C2-10 were the highest under C1 fertilizers and C2 fertilizers.The fresh root or starch yield of C1-10 were about 10%higher than those of C1-8,while those of C2-10 only increased slightly compared with C2-8 and the difference was no significant.The highest of the N,P,K utilization rate was 40.6%,43.8%,59.4%for C1-20,C2-8,C-10,respectively.In summary,the C1-10 was the optimal treatment in this field experiment,recommending to adopt 8-10 cm cassava stem and fertilization depth in cassava mechanized operation.In case of dry weather,the cassava stem depth could be appropriately increased.