Production performance evaluation of introduced cultivars of Italian ryegrass and oat in the Chengdu Plain

In the Chengdu Plain, five Italian ryegrass (Lolium multiflorum) and five forage oat (Avena sativa) varieties were comprehensively assessed using the DTOPSIS and grey correlation methods, based on seven agronomic traits, including biomass yield, leaf-stem ratio, growth rate, crude protein contents, neutral detergent fiber (NDF), and acid detergent fiber (ADF). The results indicated that there were no significant differences regarding the growth rate of all tested varieties, and the highest value was 0.70 cm·d^–1 for oat ‘Aba’ and Italian ryegrass ‘Corden’. The leaf-stem ratio of Italian ryegrass was significantly higher than that of oat (P < 0.05). The fresh and hay yields of oat ‘Cayuse’ were the highest, achieving 76 989 and 23 766 kg·ha^–1, respectively. The crude protein content of Italian ryegrass was slightly higher than that of oat, but the NDF and ADF contents were significantly (P < 0.05) lower. According to the results of two comprehensive evaluation methods, Italian ryegrass ranked higher than oat. Italian ryegrass ‘Corden’ and ‘Abundant’ ranked the highest, followed by oat ‘Cayuse’. Thus, all three of these varieties are suitable for cultivation in the Chengdu Plain.