Effect of alfalfa-grass mix combinations on the forage productivity during the sowing year in the Horqin Sandy Land

The legume-grass mixtures included alfalfa (Medicago sativa) and three grasses (Bromus inermis, Elymus nutans, and Phalaris arundinacea) to investigate herbage yield and plant height during the sowing year. The mixed combinations were two species mixtures at four intercropping ratios of legume:grass being 1:1, 1:2 , 2:2, and 2:1. The experiment was conducted in Tong Liao of Inner Mongolia in a randomized complete block design with three replications. The results showed that grass species had a significant influence on yield of mixed sowing of grasses (P<0.05), but did not significantly influence the yield of the mixed sowing alfalfa and legume-grass total yield (P>0.05). Ratios for the legume-grass mixture had a significant influence on yield of mixed species and total legume-grass yield (P<0.05). The greatest value of dry matter yield was obtained from alfalfa monoculture and it was significantly higher than total dry matter yield of the mixed grassland, and total yield of the legume-grass mixture was significantly higher than that of the monoculture of grass during the entire year (P<0.05). The highest total dry matter yield was obtained when alfalfa was mixed at a ratio of 1:1 intercrop with grass in the first cutting yield, and that of legume:grass at 2:1 was higher than other mixed sowing ratios in the second cutting yield and annual total yield. The total yields of the 1:2 mixture at all cutting times and annual total legume-grass yields were significantly lower than other mixed sowing combinations (P<0.05). Rates of legume-grass mixture had a significant influence on the growth of mixed grasses and the ratio of grass/legume yield. The growth of grasses was better in combinations of 1:2 and 2:2 legume-grass ratios than in other combinations and ratio of grass/legume yield reached 0.28~0.81 in annual yield. Growth of grasses was obviously inhibited in the 1:1 and 2:1 legume-grass mixed combinations and the ratio of grass/legume yield was 0.11~0.30 in annual yield.