This investigation was carried out on commercial organic field in the Fayoum Governorate of Egypt under conditions of natural infection, 2020/2021 and 2021/2022 to evaluate the effectiveness of four commercial biocides—Blight Stop (Trichoderma harzianum), Bio Zeid (T. album), Root Guard (Bacillus subtilis), and Bio ARC (B. megaterium)—as well as, four biocontrol agents (T. harzianum, T. album, B. subtilis, and B. megaterium) in controling Cercospora beticola Sacc, the main causal of Cercospra leaf spot (CLS) disease on sugar beet in an organic farming systems. All biocontrol agents and commercial biocides sprayed at the recommended dose in a two spray regime with 15 days between sprays, were significantly reduced Cercospora beticola, total amino acid and juice impurities (K, Na and α-a N %) in comparison to control treatment. All bioagents and biocides put to the test resulted in a significant rise in phenolic compound values, total chlorophyll, sucrose (%), purity (%), root, top and sugar yield quality of sugar beet during both seasons. Spraying Blight Stop was the most effective treatment followed by T. harzianum. B. megaterium was the least effective biocide treatment compared with the control treatment during the two growing seasons.

Net blotch infection is the most widespread and harmful disease for barley that caused substantial losses grain yield and quality, in this study Greenhouse and field experiments were carried out to recorded the net blotch reaction at seedling and adult stage of twenty barley genotypes during two growing seasons 2020/2021 and 2021/2022 .Start Codon Targeted (SCoT) markers were used to study the genetic variances and relationships among barley genotypes against net blotch reaction. The expression of severity to net blotch infection based on agro- physiological traits and net blotch reaction studied showed that Line 3 and Giza 2000 genotypes appeared the highest net blotch infection response that had lowest phenol content, chlorophyll fluorescence (FV/FM ratio) and total chlorophyll content SPAD were (42.52 mg/100g 0.510, 39. 53 SPAD reading and 43.76 mg/100g, 0.543 and 40.50 SPAD reading) respectively. However Giza 132, Giza 134, Giza 137, Giza 136, Line 4, line 5 and line 7 were proved to be the most resistant genotypes for net blotch that showed high average mean performance values for all studied agro- physiological traits over all the tested barley genotypes and scrod one under greenhouse at seedling stage with lowest net blotch infection that they were related to type R. Genetic changeability and associations among 20 barley genotypes based on using ten SCoT markers showed 77 amplified fragments, out of them 61 (77.92%) were polymorphic. The primer (SCoT -9) was highly informative marker which had higher values of total number of bands, number of polymorphic bands, polymorphism percentage, Polymorphism information content, diversity index, marker index and discriminating power DP were ( 10 ,9, 90.0, 0.389, 0.489, 0.499 and 0.692 ) respectively, so we could consider that useful primer to confirm the genetic differences among barley genotypes for net blotch reaction. The dendrogram based on SCoT showed clear pattern of clustering among the twenty barley genotypes with the resistant and susceptible for net blotch. These results could be useful for barley improvement in terms of biodiversity protection and design of new crosses for disease resistance to net blotch resistance in Egypt.