Revista de Patología Vegetal y Microbiología

Abstracto

Biofumigation Potentials of Some Brassica Crops to Control Root-knot Nematodes Meloidogyne spp., on Tomato Under Field Conditions

Shimaa Hassan , Amal A Al-Gendy, Sahar H Abdel-Baset *, Salah M Abd El-Kareem , Samia I Massoud , Mohamed Yasser Abdallah

The experiments were conducted to study the efficacy of fodder radish (Raphanus sativus var. Terranovah) and rocket salad (Eruca sativa cv. Baladi) as biofumigation crops for controlling root-knot nematodes Meloidogyne spp., on tomato plants during two successive seasons 2017 and 2018 under field conditions. Three months after cultivation of fodder radish, and rocket salad (the full blooming stage) all parts were incorporated with soil and covered with a transparent polyethylene film. After 4 weeks, the plastic sheets were removed and soil was left for two weeks later, before transplanting tomato seedlings. Results in both seasons, indicated significant reduction (p≤0.05) of nematode parameters on tomato plants. Results revealed that effect of R. sativus var. Terranovah as biofumigation crop as indicated by the percentage reduction in number of galls, egg-masses/root system, and a number of second-stage juvenile (j₂) /250 g soil (84, 90, and 84%), and (90,87, and 88%) in seasons 2017 & 2018 respectively. On the other hand, nematicide Vydate (oxamyl) 24% L recorded the percentage reduction in the number of galls, egg-mass/ root system as well as number of second-stage juveniles in soils j₂ (90,87, and 87%), and (95,93, and 90%) in season 2017& 2018 respectively. Results revealed that all plant growth criteria on tomato plants increased significantly (p≤0.05) by using the tested treatments. Results indicated that the effect of R. sativus as biofumigation crop recorded the average highest percentages (57, and 92%), and (64, and 102%) in seasons 2017 &2018 respectively. At the same time, nematicide Vydate (oxamyl) 24% L was the most effective in the average highest percentages. i.e., the plant growth vigor, increase, and fruit yield per plant (64, and 98), (73, and 107) in two successive seasons 2017 & 2018 respectively.

Gas liquid chromatography-mass spectrometry (GLC-MS) analysis of dichloromethane extract of fodder radish indicated the presence of four glucosinolates, which were identified through their volatile autolysis products. Gluconapin, the major compound was identified by 3- butenyl isothiocynate, while glucoerucin was identified by 4-(methylthio) butyl isothiocynate, which is commonly known as erucin. Sulphoraphane was released from 4-(methylsulfinyl) butyl glucosinolate (glucoraphanin) while 4-(methylsulphony) butyl isothiocyanate commonly known as erysolin was liberated from glucoerysolin. Furthermore, five GLS were also identified in rocket salad. Gluconapin was detected and its presence was identified through its epithionitrile; 4,5-epithiopentanenitrile. The isomers progoitrin and epiprogoitrin were detected by the two hydrolysis products diastereomers threo and erythro 1-cyano-2-hydroxy-3,4-epithiobutane respectively. The aromatic glucosinolate; gluconasturtiin could be identified through its liberated nitrile named as 1-benzenepropane nitrile. Sativin, the major identified compound is 4-mercaptobutyl isothiocyanate.