control on fungal rot tomato and cucumber fruits using the best concentration of aloe vera extract

Abstract

This study included isolation and diagnose the fungi causing damage and rot of cucumber and tomato fruits after harvest .And determine the best concentration of of aloe vera extract that inhibits fungal growth and sporulation .The ability of this extract in protecting tomato and cucumbers fruits under cold storage conditions .

    Alternaria alternata , Drechslera australiensis , Fusarium pseudoanthophilum and Pythium aphanidermatum were isolation from tomato and cucumbers fruits showing  symptoms . The fungus  F. pseudoanthophilum was recorded for the first time in Iraq as causer of tomato and cucumber fruits rot . Aspergillus niger , A. oryzae , A. terreus and Penicillium chrysogenum fungi were isolated from fruits surfaces by dilution method .

       Results revealed that all concentrations of  Aloe vera extract inhibited tested fungi and the concentrate of 20% was the most effective where the inhibition after  72 hours were 82.53. The results extract was capable to prevent the growth of  P. aphanidermatum completely .The extract inhibited  the germination of A. alternata 4 and Penicillium chrsogenum spores by 70.62 and 67.61% respectively .The inhibition  percentage  of  isolates spores 1, 2 and 3 of A. alternata were 54.7 , 64.46 and 60. 57%, respectively, and for  D.australiensis spores were 49.04% .

          Results of applied experiments revealed the ability to use  Aloe vera  extraction  in protecting tomatoes and cucumber fruits from  infection with rot after harvest under  cold condition . The average growth of A.alternata , D.australiensis  F.pseudoanthophilum and P.aphanidermatum after after 20 days Aloe vera  extracted treatment gave 0.09,0.07 0.12 and 0.16 cm respectively  compared with the control which gave 0.12 , 0.12 ,0.17 and 0.22 cm respectively . After 25 days the growth was 0.17 , 0.15 , 0.25 and 0.35 cm respectively compared to the control treatment which gave  0.20 , 0.15 , 0.31 and 0.49 cm, respectively .