Effect Of The Cutting Time On The Regeneration Characteristics And Yield Of The Different Varieties Of Alfalfa

This study was conducted to assess growth characteristics and yield characteristics of 40 lines of Alfalfa (Medicago sativa L.) with different origins from South Australia, North America and Europe.To evaluate the adaptation of the different varieties in the same place, select the best varieties of alfalfa with high yield and good regrowth characteristics based on the cluster analysis of cutting height and fall height of the different varieties. The trial plots including 40 cultivars were established in Gansu Agricultural University. The growth speed, regeneration capacity as well as field yield were tested. Different materials gave different growth speed, those greened up earlier and grow quickly could achieve 4 times of cutting all the year round. The plant height were measured when cutting, average height were also tested before plant cease to prow in winter. The results showed that there were significant differences in growth height, cutting height and fresh yield among different varieties.Among the 40 lines of Alfalfa, Alize,SA35056,Salado,SA10077 grow fast in the first year, especially Alize and SA10077 their plant height were low in the first cutting, high in the second cutting and the third cutting. The growth rate of SA16465 was stable.In the second year, SA35054,Salado grew fast and stable. The regrowth height of L286 was lower, the first cutting height was high but low in other cutting time. In the third year, SA1646 grew fast, the plant height was high in each cutting. The plant height of Alize was low in the first cutting and the second cutting, but in the third cutting the plant height is high.The effect of the earliest cutting on regrowth of alfalfa was obvious. After cutting process, there were significant correlations between yield and plant height, shoot numbers; the correlations between yield and leaf number, branch number, internodes number was not obvious. The dry matter decreased in the earliest cutting process; the cutting process ahead 20 days, the internodes number rose quikly in back growing period. There were obvious differences on yield, the yield discreased 57.1%, in compare with 1/10 flowering period, the growth rate was slow, the regrowth height was lower than other process.