Effect of water and nitrogen reduction on main photosynthetic physiological parameters of film-mulched maize no-tillage rotation wheat
摘要
<p id="C3">The effect of no-tillage combined with water and nitrogen reduction of mulching maize on the stability and increase of wheat yield has been verified, but the research of the photosynthetic physiological mechanism of its formation is still relatively weak. From 2018 to 2020, the split zone design was adopted, and two farming methods of film-mulched corn no-tillage (NT) and traditional tillage (CT) was arranged with two irrigation levels of traditional irrigation (I<sub>2</sub>, 2400 m <sup>3</sup> hm <sup>‒2</sup>) and traditional irrigation reduce 20% (I<sub>1</sub>, 1920 m <sup>3</sup> hm <sup>‒2</sup>) and three nitrogen application levels of 225 kg hm <sup>‒2</sup> (N<sub>3</sub>), 180 kg hm <sup>‒2</sup> (N<sub>2</sub>) and 135 kg hm <sup>‒2</sup> (N<sub>1</sub>). The results showed that farming measures and nitrogen application level had significant effects on wheat leaf area index, photosynthetic potential, SPAD value, and photosynthetic rate; irrigation level had significant effects on photosynthetic rate. During the whole growth periods, compared with CT, NT increased wheat leaf area index, photosynthetic potential, SPAD value, and photosynthetic rate by 14.5%-44.1%, 13.2%-16.3%, 7.4%-9.0%, and 14.5%-24.2%, respectively; Compared with I<sub>2</sub>, the photosynthetic rate of wheat I<sub>1</sub> decreased by 6.5%-13.6%. Compared with N<sub>3</sub>, the leaf area index, photosynthetic potential, SPAD value, and photosynthetic rate of N<sub>1</sub> decreased by 6.4%-13.6%, 7.5%-12.7%, 6.0%-10.2%, and 7.5%-17.5%, respectively. There was no significant difference between N<sub>2</sub> and N<sub>3</sub>. Cultivation measures, nitrogen application level, and irrigation level all had significant effects on dry matter accumulation and grain yield in wheat. Compared with CT, NT increased by 13.4%-16.5% and 9.0%-13.4%; Compared with I<sub>2</sub>, I<sub>1</sub> decreased by 6.5%-6.7% and 4.3%-7.4%; Compared with N<sub>3</sub>, the dry matter accumulation an