الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Occurrence and pathogenicity Isolation from decayed apple fruits, collected from different geographic locations in Al-Jabal Al-Akhdar Region in Libya revealed that the major decay pathogens were Penicillium expansum (Link) Thom, Botrytis cinerea Press, Alternaria alternata (Cke) Weber, A. flavus Linkex Gray, A. niger and R. stolonifer (Her. Ex fr) Lind2) Occurrence frequency (OF) studies showed that A. alternata proved to be the most prevalent fruit-decaying fungi in Shahat and Al-Gubba (12.4-22.8%); followed by P. expansum (14.6-18.7%) in Massa and Al-Biada and B. cinerea (11.8-16.3) in Al-Wasiata and Al-Gubba.
(3) Disease Incidence (DI) values showed significant variations. A. alternata was the most virulent (17.4-22.3%), followed by P. expansum (5.9-15.2%) and then B. cinerea (8.4-12.8) and followed by the other isolated pathogens.
(4) Pathogenicity studies in the three tested apple varieties indicated that all the tested fruit-decaying fungi were pathogenic to the tested apple variety. However, A.alternata gave the highest DI% values on GD varieties (58.3%), whereas B. cinerea on RD variety realized the minimum DI% value (16.6%).
2. Control of postharvest diseases of apple:
2.1. Biological control agents
2.1.1. In vitro studies:
(5) P. fluorescens, B. mycoides and B. subtilis were tested as bacterial biological control agents against the tested pathogens A. alternate, P. expansum and B. cinerea. B. mycoides gave the highest growth reduction rates (GRR) in A. alternate (68.3%), whereas P. fluorescens was more antagonistic against P. expansum (73.2%). B. subtilis was more antagonistic against A. alternate (61.2%).
(6) T. harzianum and T. viride were tested as fungal biological control agents. Both Trichoderma species significantly reduced growth of the tested pathogens. T. harzianum was more antagonistic on P. expansum (71.97%) and A. alternate (65.7%), whereas T. viride was more antagonistic against both of B. cinerea (40.57%).
2.1.2. In vivo studies:
(7) Treatment with P. fluorescens resulted in the lowest infection percentages against all of the tested pathogens and mostly in all the applied varieties, in particular RD (6.6% in A. alternata, 7% in B. cinerea and 12.6% in P. expansum) after 14 days of incubation.
(8) B. mycoides and B. subtilis were also more effective against fruit decays on RD than the other apple variety. However, they were still less effective than P. fluorescens. The tested bacterial agents, especially B. mycoides and B. subtilis were, relatively, less effective on GD and SK.
(9) Both of T. harzianum and T. viride fungal biocontrol agents significantly reduced fruit decay, incited by all the tested pathogens in most of the applied apple varieties. However, T.harzianum was more effective in RD varieties, inoculated with P .expansum (7.3%), B. cinerea (16%) and A. alternata (16.6%).
(10) Higher Infection% values were detected in GD varieties, pretreated with T. viride before inoculation with B. cinerea, A. alternata and P. expansum (29.3%, 27.6% and 31.6%, respectively).
2.2. Plant extracts:
(11) Eucalyptus extracts with alcohol gave the highest reductions in radial growth of the tested pathogens, attaining the reductions 81.0% for P. expansum. Inhibition percentages were 63.0% and 61.0% when water extract method was used for A. alternata and B. cinerea, respectively.
(12) Hexane and alcohol extracts of Zaater gave acceptable reduction percentages against mycelial growth of the tested pathogens.
(13) Sheeh extracts with alcohol gave the highest reduction percentage (73.0%) against P. expansum. Water and hexane extraction of sheeh resulted in high reduction rates in both A. alternate (75.0%) and B. cinerea (50.0%).
(14) Water extract of Zaater significantly reduced infection of fruit decay, caused by P. expansum in both RD and SK apple varieties (8.5% and 15%, respectively) and resulted in significant pronounced reduction in infection, caused by B. cinerea, in RD varieties only (2.5%). Treatment with alcohol and hexane extracts resulted in complete suppression of decay in RD apple fruits, incited by the tested pathogens.
(15) Wormwood (Sheeh) water extract effectively reduced infection with P. expansum in RD (3.5%), GD (19.5%) and SK (24%) apple varieties. Alcohol extracts significantly reduced infection of RD fruits with B. cinerea, A. alternata and P. expansum, where ID were 6%, 8.5% and 0.0, respectively. Hexane extract was effective against only B. cinerea and A. alternata in RD apple varieties (9% and 10%, respectively).
(16) Water, alcohol and hexane extracts of Eucalyptus were only effective against B. cinerea and A. alternata fruit decay in RD varieties, where DI values in B. cinerea were 12.5%, 7.5% and 4%, respectively; whereas in A. alternata ID% values were 5%, 4% and 8,5%, respectively. Differences in DI among the other tested treatments were insignificant.
2.3. Induction of systemic acquired resistance by chemical and biological inducers:
2.3.1. Effect on fungal radial growth:
(17) The highest reduction rates of radial growth of B. cinerea, A. alternata and P. expansum were realized by vit.B1 (51.4, 53.2 and 51.2%, respectively) and by Ca (50.7, 53.6 and 49.4%, respectively). Differences among these treatments were insignificant.
(18) The lowest GRR values were obtained by Chi in B. cinerea, A. alternata (28.7 and 29.3%, respectively) and INA in P. expansum treatment (30.3%).
(19) Treatment with the fungicides Tel and SW resulted in relatively high GRR of the tested pathogens (33.2 – 43.6%, respectively).
2.3.2.1. Effect on degree of Infection (DI):
(20) In B. cinerea experiment, GD and SK varieties, pretreated with the tested chemical inducers before inoculation showed significant DI values, compared