不同耕作措施对旱地春小麦旗叶光合特性的影响

Effects of different tillage methods on flag leaf photosynthetic characteristics of spring wheat in semi-arid area

研究了不同耕作措施下春小麦旗叶光合生理特性的变化.结果表明:不同耕作措施下旗叶光合速率(Pn)从孕穗到完熟期均呈逐步下降的趋势,但免耕结合秸秆覆盖(NTS)、传统耕作结合地膜覆盖(TP)和免耕(NT)处理的Pn在乳熟期有小幅度的回升.与处理T(传统耕作)相比,NTP(免耕结合地膜覆盖)、TP、NTS、NT以及TS(传统耕作结合秸秆覆盖)的平均Pn分别提高了15.17%1、1.26%8、.97%4、.08%和9.46%,平均蒸腾速率(Tr)分别提高了14.40%、16.00%、8.00%3、.20%和12.80%,但是保护性耕作措施(除NT外)下旗叶的平均水分利用效率(WUE)均小于传统耕作T.不同耕作措施对Pn、Tr和WUE影响最为显著的生育时期分别是乳熟期、孕穗期和乳熟期;生育时期对Pn、Tr和WUE的影响大于耕作措施对其的影响.

Some flat leaf photosynthetic characteristics of spring wheat under different tillage methods were measured in semi-arid area of the Loess Plateau. The results showed that the photosynthesis rate （Pn）under the different tillage methods was gradually decreased from booting stage to mature-ripe stage, but the Pn under no tillage with stubble retention （NTS）, conventional tillage with plastic mulching（TP） and no-till with no stubble（NT）could slightly be improved in milk-ripe stage; compared with conventional tillage（T）,the average Pn of no-till with plastic mulching（NTP）,TP, NTS, NT and conventional tillage with stubble incorporating （TS） could be improved by 15.17 %, 11.25%, 8.97 %, 4.08 % and 9.46 respectively, the average transpiration（Tr） could be improved by 14.40 %, 16.00 %, 8.00 %, 3.20 and 12.80 % respectively; however, the average water use efficiency （WUE） under the conservative tillage methods was less than that under T except NT; the growth stages in which the different tillage methods had the greatest effect on Pn, Tr and WUE were milk-ripe stage, booting stage and mike-ripe stage respectively; the effect of the growth stage on the Pn, Tr and WUE was greater than that under the different tillage methods.