Effect of Some Plant Extracts and Bio-Control on Snap Bean Root Rot Infection, Growth, Green Yield and Pods Quality During Autumn Seasons

摘要

Snap bean is considering one of the most important exportation vegetable crops in Egypt for exportation. Green pods of snap bean are an essential source of protein for vegetarian diet, but it infect by one of the serious fungus diseases i. e., root- rot disease especially at late spring and autumn seasons. So, two field experiments were carried out during two autumn successive seasons of 2018 and 2019 years at the Experimental Farm of Kaha Station, Qalubia Governorate, Egypt to evaluate two methods of adding some plant extracts and bio-control i. e., dipping the seeds before sowing and dipping the seeds before sowing with drenching the plants three times during growing season by some plant extracts i. e., Ginger, Thyme, Rosemary and Clove as well as some bio-control (Tricohdrema 34 or Biochare) treatments compared with pesticides "Tebuconazole" on reducing the influence of root rot disease and minimizing its injury as well as reflect of that on growth and yield of snap bean (Phaseolus vulgaris L) cv. paulista. The results showed that dipping the seeds before sowing by 30 minutes and drenching the plants three times during growing by plant extracts of ginger, rosemary, thyme and biochare have led to decrease root rot disease severity (%) in both seasons compared with fungicide "Tebuconazole" and the control. Additionally, the plant extracts have an effective role in decreasing the cell wall-degrading enzymes (viz. cellulose and polygalactonase) secreted by fungi causing root rot diseases. i.e., the snap bean plants treated with thyme, ginger and rosemary in both the two methods of adding which have a lowest cellulose and polygalacturonases enzyme content. On the other hand, these plant extracts led to the highest value of total phenols in snap bean plants. In the other side, the results clear that, dipping the seeds before sowing and drenching the plants three times during growing by Ginger, Thyme, Rosemary and Clove as well as bio-control (Tricohdrema 34 or biochare) induced a significant effect on the vegetative growth parameters of snap bean plants and registered higher green pods yield and best pods quality than the control. According to the obtained results, it can recommend to dipping the snap bean seeds before sowing (30 minutes) with drenching the plants three times during growing by any one of the previous plant extracts i.e., Ginger, Thyme, Rosemary or Clove as well as Tricohdrema 34 or biochare) respectively, to obtain high yield and lowest infection.