不同施钾水平对胡麻钾素营养转运分配及产量的影响

摘要

以胡麻“坝选3号”为材料，设置不施钾（K0）、低钾（K1，18．75 kg K2 O／hm2）、中钾（K2，37．5 kg K2 O／hm2）和高钾（K3，56．25 kg K2 O／hm2）4个施钾（K2 O）水平，于2011－2012年在河北省张家口市开展田间试验，研究了不同施钾量对胡麻钾素营养转运分配及其产量的影响。结果表明，胡麻根、茎、叶和籽粒等器官的钾素累积主要在生殖生长阶段，占全生育期累积量的41．28％～64．09％；与不施钾相比，施钾条件下胡麻根、茎和叶钾素转运量分别增加了35．60％，29．06％和43．75％。根、茎和叶中均有钾素转运到籽粒，转运率分别为17．78％～24．85％，14．82％～23．00％和39．40％～46．20％，对籽粒钾素的贡献率分别为6．71％～14．12％，11．24％～23．97％和17．26％～50．83％。较不施钾处理，低、中和高钾水平下籽粒产量分别增产14．90％～24．12％，29．93％～30．11％和15．65％～23．13％，且中钾处理下增产幅度最大。综合胡麻钾素积累、转运与分配规律以及籽粒产量，本试验区同等肥力土壤条件下，要实现胡麻高产高效以施钾量37．5 kg／hm2为宜。%This study aimed to identify the effect of different potassium supply levels on transportation and dis-tribution of potassium and on grain yield in oil flax.Using the oil flax cultivar “Baxuan No.3”,a field experi-ment was conducted with four potassium fertilizer application rates:control (K0 :0 kg K2 O/ha),low potassi-um (K1 :18.75 kg K2 O/ha),medium potassium (K2 :37.5 kg K2 O/ha)and high potassium (K3 :56.25 kg K2 O/ha)from 2011 to 2012 at Zhangjiakou,in Hebei Province,China.Significant differences in potassium ac-cumulation of different organs,including root,stem,leaf and grain,were observed.However,the changes in K content of each organ during the whole growing period were basically consistent and closely related to the rate of potassium fertilizer.The potassium accumulation in root,stem,leaf and grain was greatest during the reproductive stage of growth,and accounted for 41.28% - 64.09% of the accumulated potassium over all growth stages.Potassium uptake took place in all three organs:the root,stem and leaf.Compared with con-trol (K0 ),the potassium uptakes in root,stem and leaf under low potassium K1 (18.75 kg K2 O/ha),medium potassium K2 (37.50 kg K2 O/ha)and high potassium K3 (56.25 kg K2 O/ha)treatments were increased by 35.60%,29.06% and 43.75%,respectively.The potassium transportation rates from root,stem and leaf to grain were 17.78%-24.85%,14.82%-23.00% and 39.40%-46.20%,respectively,and the contribution of transported potassium to the total amount of grain potassium in oil flax was 6.71% -14.12%,11.24% -23.97% and 17.26%-50.83%,respectively.Meanwhile,compared with the control (K0 )treatment,grain yield increased by 14.90%-24.12%,29.93%-30.11% and 15.65%-23.13%,respectively,under the 3 po-tassium treatments,K1 ,K2 and K3 .Considering potassium accumulation,transportation,distribution and crop grain yield,the optimal potassium fertilizer fertilization for oil flax was 37.5 kg K2 O/ha (K2 )under the climatic conditions of the experimental area.