壳聚糖及其衍生物对连作淮山炭疽病的影响

Effects of Chitosan and Its Derivatives on Anthracnose under Continuous Cropping in Yam

本文针对连作淮山炭疽病难以防控的问题,采用离体菌落培养与大田栽培相结合的方式,在淮山长期连作、炭疽病严重的的地块上种植淮山,研究壳聚糖及其衍生物壳寡糖、禾甲安对病原菌菌落直径、抑菌持效期及大田炭疽病发病情况的影响.结果表明,壳聚糖及壳寡糖可以抑制病原菌菌丝伸长,改变菌丝结构,抑制效果最好的为壳寡糖15g/L,96h后抑菌率仍可达39.98%;壳聚糖、壳寡糖、禾甲安处理(喷施)连作淮山后,能有效抑制淮山大田炭疽病的发生,发病后27d壳寡糖2.50g/L的病情指数最低为29.36,防治效果最高,达53.1%.初步得出壳聚糖及壳寡糖抑制病原菌菌丝的伸长,改变菌丝结构,对连作淮山炭疽病有较好防治效果,其中以壳寡糖2.50g/L处理效果最好.

In the report,in order to solve the problem that anthracnose is difficult to control in continuous cropping yam,in vitro colony culture was combined with field cultivation,the yam long-term continuous cropping plot with severe anthracnose were selected as the tested plot,the effects of chitosan and its derivatives,chitosan oligosaccharide,Hejiaan on anthracnose,colony diameter,bacteriostatic duration in field,and anthracnose in field,in yam were studied.The results indicated that chitosan and chitosan oligosaccharide inhibit the filamentous extension of pathogenic bacteria and change the hyphal structure.The best inhibitory effect was chitosan oligosaccharide(15 g/L),and the bacteriostatic rate reach 39.98%after 96 hours.Chitosan,chitosan oligosaccharide,and Hejiaan treatment effectively inhibit the occurrence of anthracnose in yam field,Day 27 after onset,the disease index of chitosan oligosaccharide(2.50 g/L)was 29.36,and the control effect was 53.1%.Chitosan and chitosan oligosaccharide inhibited the hyphal extension of pathogenic bacteria and changed the hyphal structure,and had a good control effect on continuous anthracnose cropping yam,among which chitosan oligosaccharide treatment(25 g/L)was the best.