Rice

1. Stress Resistance (enzyme activity, organ phenotype)

Treatment: Two treatments were set up, namely CK (0 g/L) and FA-K (1.5 g/L), and both were applied to two batches of rice with basically the same conditions for high-temperature stress treatment. After the stress was observed, spraying was conducted for three consecutive days, while other standard operations were carried out.

Figure16. Growth of spike and grain under high temperature stress in rice treated with various methods

Result: Compared with the control, the foliar application of fulvic acid significantly reduces empty grains of rice under high-temperature stress and increases the number of grains.

Figure17. Dissociation, accumulation, and absorption of phosphorus under low phosphorus stress in rice treated with various methods

Results: Application of humic acid under low-phosphorus conditions can significantly promote rice growth and phosphorus uptake (Figure A, Figure B). In addition, fulvic acid can stimulate the release of phosphate-solubilizing root exudates, recruiting rhizosphere microbes with efficient phosphate-solubilizing abilities, thereby driving the conversion of insoluble phosphorus in rhizosphere soil into active phosphorus (Figure C).

2. Biomass (increase in each organ)

Treatment: four experimental treatments were set up, namely CK (urea 1g/L), HA0.5（0.5g/L）， HA1 (1g/L), and HA1.5 (1.5g/L). Four batches of rice seedlings with essentially the same characteristics were selected, and fertilization was applied once a week for each treatment, while other operations followed conventional practices.

Figure18. tillering status under various treatments

Result: Compared with the control treatment, humic acid can significantly promote ricetillering and vigorous plant growth.

3. Fruit (yield, coloring, internal quality (nutritional components))

Treatment: four experimental treatments were set up, namely CK (urea 1g/L), FA-K0.5 （0.5g/L），FA-K1 (1g/L), and FA-K1.5 (1.5g/L). Four batches of rice seedlings with essentially the same characteristics were selected, and fertilization was applied once a week for each treatment, while other operations followed conventional practices.

Figure19. Growth of spike and grain under various treatments

Results: Compared with the control, the application of fulvic acid significantly increased the length and width of rice grains, thousand-grain weight, and grain density.