تقييم كفاءة بعض العوامل الحيوية والمستخلصات النباتية وبعض المبيدات الكيميائية في مكافحة بعض الفطريات المرضية المسببة لمرض تعفن ثمار الرمانPunica.granatum في الحقل والمخزن ومدى انتاجها للسموم الفطرية.

Evaluating the efficiency of some biological agents, plant extracts, and some chemical pesticides in combating some pathogenic fungi that cause p

Abstract
The study aimed to conduct an environmental and biological survey of the extent of pomegranate fruit infection with pomegranate fruit rot disease and to identify the fungi causing these cases in Kerbala and Babylon governorates, and to isolate and diagnose pathogenic fungal isolates that have the ability to produce mycotoxins, in addition to evaluating the effect of some plant extracts, agricultural pesticides and yeast Saccharomyces cervisiae in protecting pomegranate fruits from attack by pathogenic fungi in the field and warehouse.
The results of isolation and diagnosis showed that all samples taken from infected pomegranate fruits, which belong to five different areas of Kerbala Governorate and three areas of Babylon Governorate, were contaminated with different fungal isolates with a contamination rate of 100%. The results of isolation and diagnosis showed the detection of 450 fungal isolates belonging to several fungal genera, the most contaminated of which was the Aspergillus spp genus, followed by the Penicillium spp genus, and in third place came the Alternaria spp genus, which is a fungus that produces mycotoxins. The results also showed the percentage frequency of fungal species, as the species Aspergillus. niger outperformed with a frequency percentage of 21.35%, followed by the species A. flavus with a frequency percentage of 4.72%. The species Alternaria alternata achieved a percentage of 3.37%, excel the species Aspergillus. ochraceus, which recorded a percentage of 2.70%, respectively and a number of them showed great virulence in causing the disease. It was found that four fungal isolates appeared that were the most virulent with a 100% infection rate within the scratching treatment, namely Aspergllus niger 4 (KTAN), Aspergillus flavus 1 (KHAF), Aspergillus ochraceous 2 (KRAO) and Alternaria alternata 2 (KCAA).
The results of nucleotide sequence analysis of 4 fungal isolates, which were isolated from different pomegranate fruit rot cases and showed high virulence in causing pomegranate fruit rot disease under controlled conditions, were diagnosed under different species. The results of nucleotide sequence analysis showed that the isolates belong to the fungi: Alternaria alternata, Aspergillus niger, Aspergillus flavus, and Aspergillus ochraceus. All isolates were registered in the National Center for Biotechnology Information (NCBI) under the special codes (PP467583.1, PQ034725.1, PQ034726.1, and PQ034727.1) respectively. The molecular nucleotide sequences achieved The highest matching rate was, ranging from 99.82 to 98.65%, with the ITS gene region when compared with the equivalent nucleotide sequences retrieved from the National Center for Biotechnology Information (NCBI) GenBank using the BLAST program for each fungal isolate individually.
The results of the storage experiment showed that coriander extract was superior and significantly superior in reducing the percentage of infection severity to 8.06% compared to the pathogen treatment only, which reached 25.88%, and with an average fungal inhibition rate of infection severity of 68.85%, followed by the treatment with Salvia officinalis, which reduced the percentage of infection severity by 9.98% and with an inhibition rate of 61.43%. While the treatments of the plant-based pesticide Palizin and the biological agent (Saccharomyces cervisiae) came last, with a reduction rate of infection severity of 10.04% and 11.06% respectively and an inhibition rate of 61.20% and 57.26% compared to the control treatment.
While the results showed that treating stored pomegranate fruits with Coriandrum sativum extract inhibited the pathogen’s ability to attack pomegranate fruits. This caused a partial reduction in the levels of mycotoxin production. Treatment with coriander extract reduced the production rate of Alternariol produced by Alternaria alternata to 65.9 μg/kg compared to the control treatment, which amounted to 93.7 μg/kg. While it reduced the production rate of Aspergillus Ochratoxin produced by Aspergillus niger by 57.8 μg/kg compared to the control treatment, which amounted to 62.10 μg/kg. While it reduced the production rate of A. Ochratoxin produced by A. ochrecaus by 20.6 μg/kg compared to the control treatment of 58.9 μg/kg. It also reduced the production an average of Aflatoxin B1 produced by Aspergillus flavus by 32.5 μg/kg compared to the control treatment, which amounted to 69.8 μg/kg.
The results of the field experiment confirmed that the plant-based pesticide Palizin was significantly superior in reducing the percentage of infection severity to 6.30% compared to the pathogen-only treatment, which reached 32.41% and with an average fungal inhibition rate of infection severity of 80.56%, followed by the Coriandrum sativum treatment, which reduced the percentage of infection severity by 7.57% and with an inhibition rate of 76.64%. While the Salvia officinalis and the biological agent (yeast Saccharomyces cervisiae) treatments came last, with an infection severity reduction rate of 8.98% and 10.31% respectively and an inhibition rate of 72.29% and 68.18% compared to the control treatment.