Abstract:
Cigar is a new economic growth point of tobacco industry in China in recent years. Root-knot nematode disease seriously infects cigar tobacco in planting. However, the species of pathogenic nematode on cigar tobacco has not been identified so far, and the green control of this disease is rarely reported. In this study, the pathogenic nematode infected cigar tobacco (cultivar: Yunxue 1#) in field of Jiangcheng County, Pu'er City was identified as
Meloidogyne javanica based on morphological characteristics of females, males and second-stage juveniles (J2), specific bands of PCR amplification and Koch's rule verification. The effects of fumigating soil with urea release ammonia catalyzed by urease from four edible fungi (
Flammulina velutipes,
Pleurotus eryngii, Lentinula edodes and
Pleurotus cornucopiae) against
M. javanica in cigar tobacco were evaluated. The results showed that the minimum concentration of NH
3 needed to kill 100% J2 was 136.8 mg/m
3. When the 4 spent mushroom substrates containing 4% urea were respectively mixed with the soil at a mass ratio of 1∶18, and under the conditions of 60% water content, at 28 ℃ for 3 d, the NH
3 concentration released by treatments ranged from 130.9 mg/m
3 to 218.7 mg/m
3, and generated the control effects ranged from 75.7% to 92.3% to the nematode disease. This results indicated that fumigating soil with "fungus residue+urea" had good application potential in the control of root-knot nematodes in cigar tobacco.