| To clarify the physiological response of Tagetes erecta L. to nitrogen and phosphorus application, three varieties of Tagetes erecta L. were used as test materials to explore the effects of different nitrogen and phosphorus ratios on protective enzyme activity, MDA (malondialdehyde), proline content, soluble protein, soluble sugar content, and agronomic indices of seedlings in a pot experiment. The results showed that the protective enzyme activity of SY-NM-01 was the highest among the three varieties tested, whereas that of SY-AW-07 was the lowest. When the nitrogen application rate was 100 kg/hm2 and the phosphorus application rate was 75 kg/hm2, the MDA, soluble protein, and proline contents of the three varieties reached minimum levels, whereas the soluble sugar content, plant height, and chlorophyll content reached maximum levels. Among them, SY-NM-01 showed the largest variation range in these indices. Comprehensive analysis showed that the optimal application rates of nitrogen and phosphorus in Tagetes erecta L. cultivation were 100 kg/hm2 (as N) and 75 kg/hm2 (as P), respectively, which are not only beneficial to plant growth but also reduce input costs, providing a theoretical reference for the efficient cultivation of marigold (Tagetes erecta L.). |
