Using Some Fungicide-Alternatives to Control Septoria Leaf Spot of Celery and Improve its Yield

Abstract

ield experiments were carried out under natural infection of Septoria leaf spot in the Experimental Farm of Sids Agricultural Research Station, Agric. Res. Center, Beni-Sweif governorate in 2015/2016 and 2016/2017 to evaluate the efficacy of hot water, organic acids, natural oils and bioagents on Septoria leaf spot and productivity of celery plants. Generally, all treatments were effective in reduction of disease severity. Also, a significant increase in fresh and dry weights of the herb, total chlorophyll as well as essential oil percent and oil yield was observed at the end of experiment. The use of the tested materials individually as seed treatments and foliar spray were less effective in reducing the disease incidence and severity than combined treatments with hot water-treated seeds and foliar spray with any of the tested materials. The highest efficacy was obtained from plots received hot water-treated celery fruits combined with phycare + thyme oil as a foliar spray in addition to the fungicide Ridomil gold MZ 68 WG. Furthermore, all the treatments showed significant increases in the defence-related enzymes, peroxidase (POD) and polyphenoloxidase (PPO) as compared with the untreated control.

Biostimulation effects of linseed and citrus oils on growth, antioxidant enzymes activity, metabolic changes and water relations of Khaya senegalensis seedlings under drought stress

“…The interaction between spraying oil and water deficit (5,7 and 9 day irrigation intervals) showed the linseed oil spray at 7% followed by 5%combined with 5 days (irrigation intervals) significantly increased chl a, b, carotenoids and CSI% compared with untreated plants with oil plus irrigation intervals. These results may be explained by the fact that the use of antitranspirant (linseed oil in this study) preserved the higher amount of water under deficit stress, and the films from it on the leaf surface could act as physical barrier between plants and foliar fungal pathogens that suggested agreement with Ghebrial and Kenawy [67] on celery plants. Several studies of essential oils (such as lemon and sweet orange), reported varying antimicrobial activity at different concentrations and decreased biochemical deteriorations [68,69].…”