CAJ | 학술논문

研究不同水分条件下分层施磷对冬小麦根长分布、水分利用效率（water use efficiency，WUE）及产量的影响，旨在找出旱地农业最佳水肥处理方式。试验设不施磷（CK）、表施磷（surface P, SP）、深施磷（deep P, DP）和侧深施磷（deep-band P, DBP）4种处理，每个施磷水平下设补充灌溉（W1）和干旱（整个生育期无补充灌溉）（W2）2种水分处理。结果表明，施磷位置及补充灌溉显著（P<0.05）影响冬小麦孕穗期根长分布、WUE 及产量，同时会改变根系空间分布。干旱胁迫使冬小麦0～<30 cm土层根长密度下降，降低17.5%，却促进了30 cm以下土层根长发育，增加13.3%，促进对土壤水分和磷素的吸收，从而提高产量。无论灌溉与否，施磷处理0～<30 cm土层根长密度、吸磷量、WUE及产量均显著高于CK（P<0.05）。施磷位置对冬小麦WUE和产量的影响随土壤水分而异，无补充灌溉时，与磷肥表施相比，磷肥深施显著增加WUE和产量（P<0.05），分别平均增加28.5%和16.0%，且深层根长（30～100 cm）与吸磷量、WUE和产量的变化趋势一致；而在补充灌溉时，与磷肥表施相比，磷肥深施却显著降低WUE（P<0.05），平均降低13.3%，且深层根长与WUE、产量的关系缺乏规律性。该试验结果表明，土壤水分供应不足时，磷肥深施有利于促进冬小麦深层土壤根系生长发育，提高对土壤水分吸收利用能力，从而利于形成高产。该研究可为理解作物生长及产量对水分养分空间耦合的响应提供理论依据。
연구불동수분조건하분층시린대동소맥근장분포、수분이용효솔（water use efficiency，WUE）급산량적영향，지재조출한지농업최가수비처리방식。시험설불시린（CK）、표시린（surface P, SP）、심시린（deep P, DP）화측심시린（deep-band P, DBP）4충처리，매개시린수평하설보충관개（W1）화간한（정개생육기무보충관개）（W2）2충수분처리。결과표명，시린위치급보충관개현저（P<0.05）영향동소맥잉수기근장분포、WUE 급산량，동시회개변근계공간분포。간한협박사동소맥0～<30 cm토층근장밀도하강，강저17.5%，각촉진료30 cm이하토층근장발육，증가13.3%，촉진대토양수분화린소적흡수，종이제고산량。무론관개여부，시린처리0～<30 cm토층근장밀도、흡린량、WUE급산량균현저고우CK（P<0.05）。시린위치대동소맥WUE화산량적영향수토양수분이이，무보충관개시，여린비표시상비，린비심시현저증가WUE화산량（P<0.05），분별평균증가28.5%화16.0%，차심층근장（30～100 cm）여흡린량、WUE화산량적변화추세일치；이재보충관개시，여린비표시상비，린비심시각현저강저WUE（P<0.05），평균강저13.3%，차심층근장여WUE、산량적관계결핍규률성。해시험결과표명，토양수분공응불족시，린비심시유리우촉진동소맥심층토양근계생장발육，제고대토양수분흡수이용능력，종이리우형성고산。해연구가위리해작물생장급산량대수분양분공간우합적향응제공이론의거。
In order to find out the best water-phosphorus (P) application method in improving grain yield and water use efficiency of winter wheat grown on the semi-arid Loess Plateau of China, this study evaluated the effects of phosphorus application at different soil depths on root length distribution, water use efficiency and grain yield of winter wheat under different water condition and analyzed the relationship between root distribution and grain yield. The experiment consisted of four P treatments and two water treatments in a randomized complete block design with three replicates. The four phosphorus levels included no P (CK), surface P (SP), deep P (DP) and deep band P (DBP) and the two water treatments were irrigation (W1) and no irrigation (W2) in the whole growth period of winter wheat. The results showed that there was large difference in root length distribution, water use efficiency and grain yield of winter wheat among different treatments. Compared with the irrigation treatment, the non-irrigation treatment significantly (P<0.05) lowered the surface soil root length (0-30 cm) by 17.5%, but significantly increased (P<0.05) deep soil root length (30-100 cm) by 13.3%, which would be helpful in promoting the absorption of soil water and P, water use efficiency and grain yield. Root length density was increased at the site of placement where P was applied under the two water treatments, particularly under water stress. Whether irrigation or not, P application (SP, DP and DBP) caused the increase of P uptake amount, water use efficiency and grain yield, compared with the CK treatment. The effect of P placement on water use efficiency and grain yield of winter wheat was different. Deep P application (DP and DBP) significantly (P<0.05) decreased water use efficiency of winter wheat compared with SP by 13.3%, while significantly (P<0.05) increased water use efficiency and grain yield under non-irrigation treatment by 28.5%and 16.0%, respectively. Furthermore, root length in deep soil layer (30-100 cm) was positively correlated with P uptake amount, grain yield and water use efficiency under non-irrigation condition,that is, the longer deep soil root length, the better water use efficiency and higher production under soil drought condition. No correlation was found between root length in deep soil layer (30-100 cm) and P uptake amount, grain yield and water use efficiency under irrigation condition, highlighting the importance of well-developed subsoil root system for both high grain yield and water use efficiency. The study suggested that deep placement of fertilizer phosphorus was a practical and feasible method of increasing grain yield and water use efficiency under water stress conditions by promoting deep root development.