Molecular Identification of Green Mold Pathogen and Impact of Formulation of Polyvinyl Alcohol and Some Organic Acid On Disease and Quality of Washington Navel Orange Fruits During Storage

Abstract

Pathogenicity test showed that every tested isolate significantly caused the green mold disease on orange fruits. Penicillium .2, was the most virulent isolate; it induced disease incidence and severity by 90.0 and 92.0%, respectively. At the National Center for Biotechnology information (NCBI) alignment showed the percentage of identity (93.75%) of Penicillium digitatum between our isolates and Gene bank isolate. The effects of Benzoic acid (BA) and Salicylic acid (SA) at 0.0, 0.5, 1.0, 1.5, and 2% against Penicillium digitatum mycelial growth were assessed. The linear growth of Penicillium digitatum was significantly inhibited by all tested concentrations, according to the results. With SA and BA at 2.0%, linear growth was completely inhibited. The greatest reduction was achieved by using SA and BA at 1.5%, which, respectively, lowered the linear growth by 86.7 and 85.6%.The linear growth of Penicillium digitatum was strongly suppressed in all formulations involving SA or BA and PVA. Complete suppression of linear growth was achieved by combining PVA at 10.0% with either SA or BA at 2.0%. The greatest reduction of 84.4 and 83.3%, respectively, in linear growth was obtained with
SA or BA at 1.5% and PVA at 10.0%. The effects of PVA at 10% combined with SA and BA at 1.5% and 2.0% were evaluated in vivo in order to examine their impact on Washington navel orange fruits green mold disease. The incidence and severity of green mold disease were shown to have been greatly decreased by all formulations, according to the results. The disease incidence and severity were lowered by 90.0 and 88.0 percent and 92.0 and 91.0 percent, respectively, when SA or BA at 2.0% and PVA at 10.0% were combined. SA or BA at 1.5% and PVA at 10.0% came next, which reduced the disease incidence by 80.0 and 78.0 % and disease severity by 80.0 and 82.0 % respectively. Previous formulations had no negative effect on fruit quality of orange fruits. All tested formulations reduced weight loss more than 38.5% and fruit disorders more than 80.0%. As for total soluble solids (TSS) there was no significant effect on total soluble solids percentage (TSS).