المكافحة الإحيائية للحلفا بالفطر C. destructans و الكلايفوسيت

الملخص EN

This experiment was carried out to evaluate the efficacy of some fungi that associated cogon grass rhizomes to infect it, and the efficiency of integration between the fungus Cylindrocarpon destructans and the herbicide Glyphosate to control cogon grass.

Results of study the effect of soil treatment with spore suspension of 17 tested fungal species of Cylindrocarpon coprosomae(GC6, GC16, GC18), C.

destructans (GC2, GC3, GC9, GC11), C.

didymium(GC8,GC21), C.

hetronema(GC1), C.

obtiusisporum(GC5), Fusarium moniliforme (GF10,GF19), Rhizoctonia solani (GR1,GR2) and Macrophomina phasolina (GM27) in cogon grass infection, caused the ability of all the isolates to infect cogon grass in a percentage ranged 61.56-96.87%.

The results also showed that all the isolates showed a significant reduction in shoot and root dry weight compared with the control treatment, the mean shoot and root dry weight in the treatments of all the isolates ranged 0.073-0.947 g/plant and 0.226-1.573 g/plant respectively while it was 1.759g/plant and 2.413g/plant respectively in the control treatment.

Results of study the host range of the pathogenic isolates GC1, GC3, GC6 and GC9 which belongs to some Cylindrocarpon species, showed the specificity of the tested fungi to infect cogon grass without effect of the other plant species.

Results of evaluating the efficiency of the integration between the biocontrol fungus C.

destructans and the herbicide glyphosate in the control of cogon grass showed the superiority of addition the herbicide glyphosate 2% with the biocontrol fungus isolates GC3 simultaneously over the treatments of addition the two control agents individually, the disease severity and the rate of rhizome degradation in their treatment 93.33% and 84.44 respectively, while the disease severity in the treatments of addition the biocontrol fungus and the herbicide glyphosate 2% individually 64.43% and 75.53% respectively, and the rate of rhizome degradation 71.11 and 57.77 respectively.

Results also indicated that all the spray treatments with 2% glyphosate individually or with addition of biocontrol fungus in the same time or after 5, 10, 15 and 20 days have been caused high percentage of rhizome buds death.

The biocontrol fungus also caused high significant reduction on percentage of germinating rhizomes arising over the soil surface compared with control treatment.

The percentage of germination in its treatment was 33.30% while it was 100% in the control treatment.