Response of strawberry plants to some abiotic inducers under stress of some root rot pathogens [electronic resource].

Includes reference.

Chemical inducers from different groups weretested, as solution for dipping the roots of strawberry plant before transplanting in the soil infested withRhizoctonia solani, R fragariae and Sclerotium rolfsii, and foliar sprayed after7 day to induction a systemic resistance. In vitro, mycelial growth of three tested fungi was mostly inhibited by SA, Rizolex-T and Ethephon, but not or little affected by another tested inducers. Under greenhouse conditions, CUSO. completely prevented disease incidence (as % of dead plants) in the presence of R. fragariae and R solani either after21 or 45 daysfrom infestation. The sameeffectwas achieved by BA againstR. fragariae. After 21 days MgSO., Bion 50%, and Ethephon were almost equal with Rizolex-T 50%,but lowesteffectwasrecorded by usingAscorbic acid after21 and 45 days. Under field conditions, all abiotic inducers were declined the dead strawberry plants (%) than untreated control after 21 and 45 days in both seasons (2004 -2005). However. abiotic were more effective in the secondseason than the first, especially SA, CuSO. thenBA, AAandBion 50%. Clearincrease in the shootand rootlengths of strawberry plants as response to treatroent with all tested abiotic inducers than untreated plantswas observed Ethephonexceeded the othersfor the induction of the resistance against root-rot pathogens, and enhanced the growth parameters of strawberry plants under greenhouse conditions. KH2PO. and SA inducers increased theenzymeactivities of peroxidase, polyphenoloxidase, chitinase and p,I-3-glucanase than otherabiotics, while little activities were recorded with other treatments. Lignin contentwas increased in the treated plantsin response to all inducers than untreated. Key words: Strawberry, abiotic inducers, root-rot, Rhizoctonia, Sclerotium, plant growthparameters, enzyme activities.

Summary in Arabic.

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