Control of root knot disease in Ammi majus using organic amendments

Chemical pesticides are hazardous to the harmony existing in nature and needs to be replaced by an effective alternative that is safe and sound both for the organisms and environment. The experiment was conducted to study the impact of different organic amendments (cow dung, vermicompost, Ricinus communis, Euphorbia hirta and Amaranthus viridis) against root-knot nematode on Ammi majus. The soil was amended with five organic matters @ 20g/kg soil and left for decomposition for 20 days. Seeds of Ammi majus were sown and inoculated with 2000 J2 of Meloidogyne incognita after 15 days of seed emergence. All the amendments significantly enhanced plant growth parameters (plant height, plant fresh weight and plant dry weight) both in the presence and the absence of nematode and reduced the rate of nematode reproduction and multiplication. Highest impact was registered in case of cow dung and lowest in case of Amaranthus viridis. All the physiological parameters except phenol content decreased in the presence of M. incognita alone. The maximum improvement in all physiological parameters except phenol was recorded in plants treated with cow dung and minimum improvement in plants treated with Amaranthus viridis. The nematode related parameters (galls, fecundity, and soil and root population) were high in plants treated with M. incognita alone. The highest decrease in nematode related parameters was observed in plants treated with cow dung, and lowest decrease in plants treated with Amaranthus viridis. Thus in the present study ecologically sound management modules were generated by utilising some organic fertilizers.