Abstract:

In order to explore the appropriate application amount of silicon fertilizer for pepper cultivation, the effects of different silicon fertilizer levels on the growth, yield and quality of pepper were studied. By adopting pot test and using ‘Xinxiang No.2’ pepper as the test material, this experiment analyzed the changes about the leaf SPAD value, photosynthetic characteristics, related agronomic traits, yield and quality indexes of peppers. The results showed that compared with conventional fertilization, the net photosynthetic rate of pepper leaves increased by 14.07% to 17.76% under the silicon application treatments in the pre-fruiting period. The net photosynthetic rate of pepper leaves increased by 16.16% under Si3 treatment (conventional fertilization+ silicon fertilizer 0.3 g/pot) and 21.14% under Si5 treatment (conventional fertilization+ silicon fertilizer 0.5 g/pot) in the middle to late fruiting period. The height of pepper plants and fruit diameter increased with the increase of silicon fertilizer usage. The yield of Si3 and Si5 treatments increased respectively by 28.21% and 65.63%. The vitamin C content of chili peppers treated with silicon fertilizer treatments was significantly higher than that of the conventional fertilization. The soluble protein and soluble sugar contents were the highest under the Si3 treatment, which increased respectively by 20.82% and 47.35%, compared with that of the conventional (NPK) treatment (non-silicon fertilizer). The nitrate content of the peppers of silicon fertilizer treatments was significantly reduced, which decreased by 33.34% to 34.95% compared with that of NPK treatment. In conclusion, the application of silicon fertilizer can not only improve the yield of pepper, but also improve the fruit quality. For pepper, applying 0.5 g of silicon fertilizer per pot (equivalent to applying 75 kg of silicon fertilizer per hectare) has the best effect.

Key words: silicon fertilizer, yield, quality, pepper, photosynthetic characteristics, agronomic traits