Aida M. El-Zawahry
Assiut University, Egypt
Aida Mohamed Ibrahim El-Zawahry is a professor of Plant biology, Faculty of Agriculture, Assiut University, Egypt. She is working under Plant pathology department and her research area is Nematode Diseases.
The effect of five plant species (Tagetes erecta L., Datura stramonium L., Nerium oleander L., Ipomea palmata L. and Santolina chamaecyparissus L.) on severity of Tylenchulus semipenetrans on citrus rootstocks (Citrus sinensis, C. reticulate grafted on C. aurantium and C. sinensis grafted on C. aurantium) was investigated in greenhouse and laboratory conditions. All plant species reduced the larval population of T. semipenetrans and their effect increase as the period increase. Ipomea palmata gave the highest percentage of reduction when intercropped with C. sinensis and C. reticulate grafted on C. aurantium 20.5 and 25% respectively. Nerium oleander and Datura stramonium came next when intercropped with C. reticulate grafted on C. aurantium 13.5 and 11% respectively. While Datura stramonium gave the highest percentage of reduction when intercropped with C. sinensis grafted on C. aurantium and Tagets erecta gave the lowest percentage of reduction when intercropped with the three rootstocks. Root extracts of Datura stramonium gave the highest effect on juvenile mobility of citrus nematode at 5% dilution after 48 hrs with only 50% mobility followed by 55%, 64%, 71.7% and 73.3% for T. erecta, Santolina sp., Nerium sp. and Ipomea sp., respectively. Extract of Datura sp. at 5% concentration, for 48 hrs. exposure showed the highest toxicity for nematode larvae mobility 45.3% followed by 51.3%,55.3%, 60 and 67% for T. erecta, Santolina sp., Nerium sp. and Ipomea sp., respectively.