免耕条件下不同量秸秆覆盖还田提高东北黑土区玉米光合性能和产量的效应

鲁悦; 鲍雪莲; 霍海南; 杨雅丽; 赵月; 解宏图; 梁超; 何红波

doi:10.11674/zwyf.2022507

免耕条件下不同量秸秆覆盖还田提高东北黑土区玉米光合性能和产量的效应

Effects of different amounts of stover mulching on improving photosynthetic characteristics and yield of maize in Mollisol of Northeast China under long-term no-tillage

摘要

摘要:
目的探究东北黑土长期免耕及不同秸秆覆盖还田量下玉米光合性能及产量的变化规律，为科学应用免耕秸秆覆盖还田技术提供理论支撑。
方法东北黑土区保护性耕作定位试验始于2007年，设置5个处理，分别为传统垄作秸秆不还田(对照， CT)及免耕配合当季收获玉米秸秆量的0%、33%、67%和100% (NT-0、NT-33%、NT-67%、NT-100%)还田。于2021年玉米苗期、拔节期和抽雄期，测定玉米叶片净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)等光合参数，以及叶绿素含量和叶面积；于成熟期，测定籽粒产量及其构成因素。
结果与CT处理相比，4个免耕秸秆覆盖处理不同程度地提高了苗期的Pn，以及拔节期和抽雄期玉米叶片的Pn、Gs和Tr；NT-67%和NT-33%、NT-100%处理还显著降低了拔节期和抽雄期的胞间二氧化碳浓度，显著提升了抽雄期叶片的叶绿素含量(P<0.05)。NT-100%处理在拔节期和抽雄期的光合效率最高，光合性能显著优于其他处理，NT-67%处理有个别指标略低于NT-100%，但仍与CT、NT-0和NT-33%处理差异显著。免耕结合秸秆覆盖还田提高了玉米穗的行粒数、百粒重和籽粒产量，NT-33%、NT-67%、NT-100%处理的籽粒产量均显著高于NT-0和CT处理，而后二者间差异不显著。净光合速率与产量之间存在显著正相关关系(P<0.01)。
结论免耕结合秸秆覆盖还田能够提高玉米抽雄期的叶绿素含量、净光合速率、气孔导度和蒸腾速率，降低玉米光合作用的非气孔限制，提高对胞间CO₂的利用能力。秸秆覆盖量为67%～100%时，提高净光合速率、叶绿素含量以及玉米行粒数、籽粒产量的效果突出，是东北黑土区较为理想的耕作模式。

Abstract:
Objectives This study investigated maize yield and photosynthetic characteristics under the influence of stover mulching and long-term no-tillage in the mollisol of Northeast China. We aim to propose a suitable no-tillage and stover mulching technology system in the study region.
Methods The conservation tillage field experiment started in 2007 with a single maize cropping system. The treatments included conventional tillage (CT) and no-tillage combined with stover mulching at 0%, 33%, 67%, and 100% of the harvested maize stovers, denoted as NT-0, NT-33%, NT-67%, and NT-100%, respectively. We measured the net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), chlorophyll content, and leaf area at the maize seedling, jointing, and tasselling stages in 2021. Maize yield and yield components were measured at the maturity stage.
Results Compared with CT, the four no-tillage treatments improved the Pn of seedling stage, Pn, Gs, and Tr at the jointing stage and tasseling stage. NT-67%, NT-33% and NT-100% (P<0.05) decreased intercellular CO₂ concentration at the jointing or tasselling stages, while NT-67% and NT-100% maintained higher chlorophyll content at the tasselling stage. NT-100% recorded the highest photosynthetic efficiency at the jointing and tasselling stages, followed by NT-67%, with (P<0.05) higher values than CT, NT-0, and NT-33%. All the NT with stover mulching treatments (NT-33%, NT-67%, NT-100%) increased the kernel number per row, 100-kernel-weight, and grain yield, and there was no significant difference (P>0.05) in yield between NT-0 and CT. The Pn values were significantly (P<0.01) correlated with maize yield.
Conclusions No-tillage combined with stover mulching is effective in increasing chlorophyll content, Pn, Gs, Tr, and the capacity of utilize intercellular CO₂ at the tasselling stage, which enhances maize yield. No-tillage combined with 67%−100% of the harvested maize stover showed a good potential for maize net photosynthetic efficiency, making it a promising approach under the no-tillage condition in the Mollisol of Northeast China.

HTML全文

参考文献(39)

施引文献

资源附件(0)