Induced Systemic Resistance in Tomato Plants against Meloidogyne spp by Seed Treatment with Beta, Amino Butyric Acid and Benzothiadiazol

Treatments of tomato seeds with BABA or BTH significantly (p=0.05) reduced nematode infestation of tomato plants. BABA treatment produced significantly the lowest average root gall index (RGI), 2.44 followed by BTH, 3.22 and 3.55 for the untreated nematode infested control plants 15 days after nematode inoculation(ANI).Treatments with BABA and BTH for 30, 60 and 120 min. also caused significantly (p=0.05) less nematode infestation compared with the untreated control plants. BABA caused significantly the lowest average RGI, 1.77 compared with 3.66 and 4.55 for BTH and control respectively. The 120 min  BABA treatment recorded significantly the lowest average number or J2 in the roots of tomato plants compared with 75.55 and 116.66 J2 in the roots BTH and control plants respectively. When seeds were socked for 120 min, root average fresh weight (RFW) and root dry weight (RDW) were significantly less, 2.58 and 0.14g in BTH treatments of seeds compared with 1.86, 0.10g for BABA and 5.01 and 0.29g for control respectively 50 days ANI. When seeds were socked for 120 min, the highest average SFW and SDW were, 8.05, 0.68g in BABA treatments, followed by 3.29, 0.22 and 2.43, 0.12g in BTH and control treatments respectively. The highest average SFW and SFW were also recorded for BABA treatments, 2.43, 0.12g followed by 1.5, 0,093 and 1.59, 0.092g in BTH and control respectively 15 days ANI. Similarly, BABA caused the highest average shoot weights 30 and 50 days ANI followed by BTH and control treatments. Keywords: Induced  resistance, Meloidogyne spp, ?,amino butyric acid, Benzothaiadiazole, Seed treatment, Tomato

Induction of Pathogenesis Related Proteins and Phenol in Chickpea Plants Treated with Bio-Agents in Response to Infection by Fusarium oxysporum f.sp. ciceri

Soil and seed treatments with bio-agents, bio root care (BRC), non pathogenic Fusarium oxysporum (NFo) and Rhizobium leguminisarum (R.l) indicated induced acquired resistance against Fusarium oxysporum f.sp. ciceri (Foc) in chickpea plants. This induced resistance was manifested by the accumulation of phenols and pathogenesis related protein in treated plants compared with control treatments (BRC, NFo and R.l and plants inoculated with the pathogen alone and untreated plants). Significantly (p=0.05), the highest rate of accumulation of phenols, 286.5µg gfw-1 and peroxidase activity, 68.3min-1 gfw-1 when soil was treated with NFo before inoculation with Foc compared with  other test treatments. Maximum accumulation of phenols, 228.0 µg gfw-1 was at day 5 after Foc inoculation, and maximum peroxidase activity 62.3 min-1 gfw-1 was at day 4 after Foc inoculation. The highest rate of phenylalanine ammonia lyase activity was scored when seeds were treated with BRC and NFo with no significant differences. PAL activity was 139.6 for BRC and 141.3 nM cinnamic acid min-1 gfw-1 for NFo and scored maximum activity of 99.7 nM cinnamic acid min-1 gfw-1 at day 5 after Foc inoculation. The highest rate of glucanase activity was 33.5 µM min-1 gfw-1 when seeds were treated with BRC compared with other test treatments and scored maximum activity of 29.0 and 29.5 µM min.-1 gfw-1 at day 4 and 5, respectively, after Foc inoculation

Red Light-Induced Systemic Resistance to Root knot Nematodes in Tomato

This study was conducted to evaluate efficiency of red light to induce systemic resistance in tomato plants grown in 1kg plastic pots under green house conditions against Meloidogyne spp. Results indicated that tomato seedlings exposed to red light for 2 and 3wks were significantly (p=0.05) more resistant to the root knot nematodes than seedlings exposed to white light (control seedlings). This was manifested by the less number of galls on the roots of treated compared with control plants 30d after inoculation. Root gall index(gi) was 2.77 for red  light treated and 5 for control plants. Root fresh and dry weight was 5.00 and 0.39 g for red light treatment compared with 6.31 and 0.64 g for white light control treatment respectively. Significantly (p=0.05) less (55) second stage juveniles (J2) enter the roots of red light treated plants compared to 123.66 J2 in control. Keywords: Induced  resistance, Meloidogyne spp, Red light, Tomato