Effects of Different Food Waste Formulation Substrates on Growth and Physiological and Biochemical Characteristics of Celosia Cristata and Their Comprehensive Evaluation

In order to evaluate the application effect of food waste compost on grass flower cultivation substrate, Using Celosia cristata as experimental material. 8 kinds of formula substrates were prepared with food waste, garden waste, peat soil and plain soil as the main substrates according to different volume ratios. The physicochemical properties of different substrates and their effects on the growth morphology and physiological indexes of the grass flower were studied. The results showed that: adding 10%~30% of food waste to the substrate resulted in a suitable bulk density, total porosity, pH, EC, and total nutrient content, which could meet the growth needs of Celosia cristata. Compared with the CK, adding food waste significantly increased the total nitrogen, available phosphorus, available potassium, and cation exchange capacity in the substrate. The plant height, crown diameter, leaf length, fresh weight, and dry weight of Celosia cristata all increased with the addition of food waste. Compared with the CK, the plant height, crown diameter, and leaf width of the A6 treatment increased by 38.9%, 39.2%, and 36.2%, respectively. The addition of food waste compost affected the photosynthetic indexes and nutrient accumulation of Cristata coronata. Except for A4 treatment, the net photosynthetic rate, chlorophyll content, soluble sugar content and soluble protein content of A1-A7 treatment were superior to CK treatment. The comprehensive evaluation results of principal component analysis showed that the highest scores of A6 and A5 treatments were 1.131 and 0.478, respectively, and the growth index of Celosia cristata was also better. Considering the economic factors such as the amount of peat soil, A5 treatment is recommended as the best formula substrate for Celosia cristata cultivation.