Effects of different fertilization treatments on agronomic characters, yield, and quality of forage mulberry in the soil of rare earth tailings in southern Jiangxi

This study was conducted to analyze the effects of different fertilization treatments on the survival rate, agronomic traits, yield, and quality of forage mulberry (Morus alba ‘Yuesang No. 11’) in the soil of rare earth tailings in South Jiangxi. A randomized field block design was used to set up six fertilizer treatments: control group (CK: no fertilization), cattle biogas liquid (Z), decomposed cattle dung (F), decomposed cattle dung + cattle biogas liquid (F + Z), vermicompost (Q), and vermicompost + cattle biogas liquid (Q + Z); each treatment had five replicates. The survival rate, agronomic traits, yield, and quality of forage mulberry were measured for three consecutive years. The results showed that, compared with CK, the other fertilization treatments increased the survival rate, plant height, main branch stem diameter, total branch number, total leaf number, plant weight, yield, and crude protein content of forage mulberry. The survival rate, plant weight, and yield of Q + Z treatment were the highest, with yields of 2.53, 21.81, and 42.14 t·ha⁻¹ in three years. The fuzzy membership function mean value method was used to comprehensively evaluate the feed value of forage mulberry. The Q + Z treatment had the highest mean membership function value. In conclusion, application of cattle biogas slurry, decomposed cattle dung, and vermicompost to soil rare earth tailings in southern Jiangxi improved the survival rate, agronomic traits, yield, and quality of forage mulberry. The best fertilization treatment was vermicompost + cattle biogas slurry.