氮肥减施与接种根瘤菌对大豆光合与产量的影响

The Effect of Nitrogen Fertilizer Reduction and Rhizobium Inoculation on Soybean Photosynthesis and Yield

为揭示氮肥减施与接种不同根瘤菌对大豆光合作用及产量的影响,通过设置不同减氮量+接种根瘤菌处理,研究其对大豆净光合速率、蒸腾速率、气孔导度、胞间CO_2浓度及大豆产量的影响。结果表明:在开花期, T1(1/2施氮+拌种NF)、T2(1/2施氮+土壤施用NF)、T3(1/2施氮+拌种DF)处理的净光合速率相对于CK分别提高了50.4%、30.1%、29.6%。所有处理较常规施肥(CK)的蒸腾速率、胞间CO_2浓度、气孔导度均有所上升,而大豆叶绿素含量较CK差异不显著,各处理的叶片干重较CK差异不显著,除T3处理外,各处理的茎干重较CK差异也不显著。进入结荚期后,T1、T2处理的胞间CO_2浓度较CK分别提高了34.3%、47.0%,各处理净光合速率较CK均下降,而蒸腾速率、气孔导度均高于CK,除T4、T5外,叶绿素含量较CK差异不显著。除T2处理外,各处理的叶干重均低于CK,茎与荚皮干重较CK差异不显著,籽粒干重在所有减1/2施氮量+接种根瘤菌处理中均显著高于CK。在鼓粒期,各处理的净光合速率、蒸腾速率、胞间CO_2浓度较CK差异不显著,气孔导度均高于CK,不施氮肥处理的叶绿素含量均显著低于CK。各处理的叶片干重均显著低于CK,但茎、荚皮干重与CK相比差异不显著,且籽粒干重有一定升高趋势,T3处理籽粒干重较CK提高了24.6%;在成熟期,1/2减氮+接种根瘤菌处理基本上均能提高大豆的产量及其构成因子,尤其是T3处理较CK产量提高9.75%。

In order to revealed the effects of nitrogen fertilizer reduction and different of rhizobia inoculation on soybean photosynthesis and yield, the effects of nitrogen fertilizer reduction and rhizobia inoculation on net photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO2 concentration and soybean yield were studied by setting different nitrogen reduction and rhizobia inoculation treatments. Results showed that: In the flowering period, T1(1/2 N + seed mixing NF), T2(1/2 N + soil application of NF) and T3(1/2 N + seed mixing DF) processing of net photosynthetic rate compared with the CK increased by 50.4%, 30.1% and 29.6% respectively, the transpiration rate, intercellular CO2 concentration and stomatal conductance of all treatments increased compared with conventional fertilization(CK), while the chlorophyll content of soybean was not significantly different from CK, dry weight of leaves in each treatment was not significantly different from that of CK,except for T3 treatment, the stem weight of each treatment was not significantly different from that of CK. After entered the podding stage, the intercellular CO2 concentration of T1 and T2 treatment was 34.3% and 47% higher than that of CK respectively, the net photosynthetic rate of each treatment decreased, while the transpiration rate and stomatal conductance were higher than CK, except T4 and T5, the chlorophyll content was not significantly different from that of CK, except T2 treatment, the dry weight of each treatment was lower than that of CK, and the dry weight of stem and pod was higher than CK, different treatment was not significant, dry weight of seed was significantly higher than that of CK in all 1/2 nitrogen application + rhizobium treatment. In the seed filling stage, the difference among net photosynthetic rate, transpiration rate, and CK of each treatment were not significant, and the stomatal conductance was higher than CK, which was not treated with nitrogen fertilizer. The chlorophyll content was significantly lower than that of CK, dry weight of leaves was significantly lower than that of CK, but the stem, pod dry weight were not significantly different from CK and seed dry weight had a certain upward trend, seed dry weight of T3 was 24.6% higher than that of CK. At the full maturity, 1/2 nitrogen reduction + inoculation Rhizobium treatment can basically increase the yield of soybean and its constituent factors especially the T3 treatment increased the yield by 9.75% compared with CK.