# Effects of organic-inorganic complex fertilizer on the growth and physiological characteristics of ‘Qi-Nan’ agarwood from Aquilaria sinensis (Lour.)

## TL;DR

This study examines how different amounts of organic-inorganic fertilizer affect the growth and health of ‘Qi-Nan’ agarwood seedlings.

## Contribution

The study identifies the optimal fertilizer level for improving growth and physiological traits in ‘Qi-Nan’ agarwood seedlings.

## Key findings

- Applying organic-inorganic complex fertilizer up to 7-11g/plant significantly improves seedling growth and physiological activity.
- Excessive fertilizer application inhibits growth and reduces physiological benefits.
- Seedling height and ground diameter correlate positively with soluble sugar, peroxidase activity, and chlorophyll content.

## Abstract

This paper is to study the effects of different levels of fertilization on the growth, physiological characteristic of ‘Qi-Nan’ agarwood seedlings. The experiment was conducted under potted conditions using a single factor experiment. Organic-inorganic complex fertilizer was used as the basal fertilizers, and 7 fertilizer gradients ranging from 0 g/plant to 23 g/plant were set up. The result showed that: (1) within a certain range, with the increase of organic-inorganic complex fertilizer application, the growth and physiological activity of ‘Qi-Nan’ had an incremental effect, but this effect would be inhibited when the fertilizer application was too high. (2) After fertilization, the contents of free proline (FP) and malondialdehyde (MDA) decreased, while the contents of osmotic regulatory substances and chlorophyll increased. (3) The correlation analysis showed that seedling height and ground diameter of ‘Qi-Nan’ seedlings were significantly positively correlated with soluble sugar content, peroxidase activity and chlorophyll content. (4) Membership function analysis showed that organic-inorganic complex fertilizer had a significant effect on the growth of ‘Qi-Nan’ seedlings, and the optimal fertilizer level of single application of organic-inorganic complex fertilizer was 7-11g/plant. Therefore, the optimal application level of organic-inorganic complex fertilizer for the seedling cultivation of ‘Qi-Nan’ was 7g/ plant.