保水剂施用量对土壤水分利用及马铃薯生长的影响

Effects of super absorbent dosage on water use of soil and growth of potato

针对宁夏中部半干旱偏旱区,干旱少雨、土壤水分蒸发强烈、马铃薯低产等突出问题,采用2种土壤保水剂（沃特保水剂和微生物保水剂）,以不施用保水剂处理为对照,研究了保水剂不同施用量对旱作土壤水分、马铃薯生长、产量和水分利用效率的影响。结果表明：在马铃薯关键生育期,0-100cm土层土壤贮水量随保水剂施用量增加而增加,施用沃特保水剂60kg/hm^2和90kg/hm^2使土壤贮水量分别较对照（不施保水剂）显著提高55.1%和62.1%;施用微生物保水剂可保蓄马铃薯生育前期土壤水分含量,而施用沃特保水剂可提高马铃薯生育后期土壤水分含量;施用微生物保水剂不同量可明显促进马铃薯初花期植株的生长,进入块茎膨大期施用沃特保水剂不同量对马铃薯生长的促进作用效果显著。与对照相比,施用沃特保水剂90kg/hm^2的增产和提高作物水分利用效率效果最佳,分别较对照提高41.4%和86.5%;而施用沃特保水剂60kg/hm^2的商品薯率最高（87.5%）。穴施保水剂可有效改善马铃薯关键生育期土壤水分状况,促进作物生长发育,提高作物的产量和水分利用效率,以施用沃特保水剂60-90kg/hm^2的增产和提高作物水分利用效率效果最佳。

The semi-arid area in middle of Ningxia has suffered from dry climate,which causes intensive evaporation of soil and low yield of potato.Therefore,a field study was conducted to determine the effects of super absorbent dosage on water status of dryland soil,growth and yield of potato,and water use efficiency（WUE）,by comparing two different types of super absorbents（Wote and Microbe）.Two super absorbents were diluted in ratio of 1∶100before bunch planting at different application rates.Two super absorbents in different dosage in the experiments were set as follows：Wote super absorbent of 30kg/hm^2（M2）,Wote super absorbent of 60kg/hm^2（M4）,Wote super absorbent of 90kg/hm^2（M6）,Microbe super absorbent of 30kg/hm^2（N2）,Microbe super absorbent of 60kg/hm2（N4）,and Microbe super absorbent of 90kg/hm2（N6）.The treatment with no super absorbent applying was marked as the control.The results showed that,the application of Wote or Microbe super absorbent had greatly improved the water storage of soil layers at 0-100 cm from early florescence stage to maturity stage of potato,and the effects increased along with theapplying dosage.The M4 and M6treatments had better effect on water conservation,and water storage of soil layers at 0-100 cm were 55.1% and 62.1% higher than that of the control,respectively.The soil water contents of Microbe super absorbent treatments were significantly higher than that of the control in the early stage of potato.However,the Wote super absorbent treatments significantly improved soil water content at expansion-maturity stage.The application of Microbe super absorbent significantly promoted the growth in the early florescence stage of potato,with plant height,stem diameter and biomass of potato significantly higher than the control.In contrast,the application of Wote super absorbent significantly promoted the growth at expansion-maturity stage of potato,with plant height,stem diameter and biomass of potato significantly higher than the control.Higher yield and WUE were also achieved by the application of Wote and Microbe super absorbents,with optimum dosage of 90kg/hm^2 for Wote super absorbent,and the yield and WUE of potato were increased by41.4% and 86.5%,comparing with the control,respectively.Meanwhile,the commodity rate was the highest（87.5%）with optimum dosage of 60kg/hm^2 for Wote super absorbent.In conclusion,the soil super absorbents could not only improve the water status of soil and WUE,but also promote the growth and yield of potato.The potato yield,WUE and commodity rate were the highest in the treatments of Wote super absorbent of 60-90kg/hm^2.