旱地小麦休闲期耕作施肥下氮磷对幼苗的影响

采用大田试验研究旱地小麦休闲期深松+深施有机肥条件下不同施氮量、不同氮磷配比对冬前幼苗抗旱性的影响。结果表明,施氮量为150kg.hm-2时,越冬期0～60cm土壤蓄水量以N、P比为1∶1显著最高,施氮量为225kg.hm-2时,以1∶0.75显著最高。增加施氮量,可增加越冬期幼苗的株高、分蘖数、主茎叶龄、单株叶面积、单株干物质量及叶片可溶性糖含量,可显著增加N、P比为1∶0.5和1∶0.75条件下丙二醛含量、脯氨酸含量,可显著降低POD活性,可显著降低N、P比为1∶0.5、1∶0.75条件下SOD活性。结果还表明,施氮量为150kg.hm-2时,增加施磷量,可增加分蘖数、单株干物质量、MDA含量,可降低POD活性、脯氨酸含量、可溶性糖含量;施氮量为225kg.hm-2时,株高、分蘖数、单株叶面积、单株干物质量及MDA含量均以N、P比为1∶0.75最高,POD活性、SOD活性、脯氨酸含量、可溶性糖含量均以N、P比为1∶0.75显著最低。因此,旱地小麦休闲期深松+深施有机肥条件下适当增加施氮量且N、P比为1∶0.75时有利于提高土壤蓄水量,增强旱地小麦的抗旱性。本研究可为旱地小麦的高产稳产提供理论依据。

Effect of Nitrogen and Phosphorus Fertilizer Management on Seedling under Tillage in Leisure Period

Field test was carried out to study the effect of nitrogen and phosphorus fertilizer management on dryland wheat seedling under the conditions of subsoiling and deep fertilization with organic fertilizer in leisure period.The results showed that water storage of the soil at depth of 0~60 cm was the highest with N/P ratio of 1∶1 for nitrogen application rate of 150 kg·hm-2,and N/P ratio of 1∶0.75 for nitrogen rate of 225 kg·hm-2.Increase of nitrogen fertilization could increase plant height,tiller number,leaf age of caulis,leaf areas per plant,plant dry weight and soluble sugar content in leaves.It could also increase the content of malondialdehyde and proline and decrease POD and SOD activities for the corresponding N/P ratios.With nitrogen application rate of 150 kg·hm-2,the tiller number,plant dry weight and the contents of MDA increased,the POD activity,contents of proline and soluble sugar decreased.With nitrogen rate of 225 kg·hm-2 and N/P ratio of 1∶ 0.75,plant height,tiller number,leaf area per plant,plant dry weight and content of malondialdehyde were the highest and POD and SOD activities,content of proline and soluble sugar were the lowest.So,it is favorable to improve the soil water storage capacity,and to enhance drought-resistance for dryland wheat by increasing nitrogen application and setting N/P ratio as 1∶0.75 after subsoiling and deep organic fertilization in the leisure period.This paper can provide theoretical foundations for improving yield of dryland wheat.