Evaluation of different silage maize varieties in karst regions

The purpose of this study was to select silage maize species suitable for planting in karst regions by investigating the growth performance, agronomic traits, and nutritional quality of different silage maize. A randomized block design experiment with three blocks was conducted, and each block contained six maize species, namely ‘Quchen No.11’, ‘Zhuqing No.1’, ‘Jinyu 908’, ‘Jinyu 818’, ‘Heyu 9566’, and ‘Qianqing 446’). The results have shown that ‘Jinyu 818’ yielded the highest fresh grass of up to 60.22 t·hm⁻². The air-dried matter content for all the species ranged from 35% to 44.5%, and the specific gravity of the ear was higher than that of the stem and leaf. The spike height was almost the same as the stem height. The tallest plant height was recorded for ‘Zhuqing No. 1’ (325.44 cm), followed by ‘Jinyu 908’ (291.38 cm) and ‘Jinyu 818’ (290.57 cm). According to evaluation of nutritional qualities, CP contents and ADF contents of ‘Jinyu 818’, ‘Heyu 9566’ and ‘Jinyu 908’ met the requirements of the national standard for first-class silage maize. Grey correlation degree analysis was used to estimate the values for silaging. The results have shown that the silaging value for ‘Jinyu 818’ was the highest, followed by ‘Zhuqing No. 1’, ‘Heyu 9566’, ‘Qianqing 446’, ‘Jinyu 908’, and ‘Quchen No. 11’, in that order. In conclusion, ‘Jinyu 818’ is the most suitable species for karst regions, due to its high yield, excellent agronomic traits, and high nutritional values.