Thesis Abstract

Abstract
Crown gall, caused by the soil-borne pathogen Agrobacterium tumefaciens, is a serious disease affecting a wide range of plant species, including roses and tomatoes. This study aimed to investigate the potential of garlic extract as a preventive measure against crown gall in rose and tomato plants. The experiment involved treating plants with various concentrations of garlic extract and assessing the incidence and severity of crown gall symptoms. Results showed that the application of garlic extract significantly reduced the development of crown gall in both rose and tomato plants compared to the control group. The effect was dose-dependent, with higher concentrations of garlic extract providing better protection against the disease. Furthermore, the treated plants exhibited overall healthier growth and vigor, indicating a potential positive impact of garlic extract on plant health beyond just disease prevention. In addition to the direct effects on crown gall incidence, the study also explored the underlying mechanisms of action of garlic extract in combating the pathogen. It was found that garlic extract had antimicrobial properties that could inhibit the growth of Agrobacterium tumefaciens in vitro. This suggests that the preventive effects of garlic extract on crown gall may be attributed to its ability to suppress the pathogen's growth and colonization in plant tissues. Overall, the findings of this study demonstrate the potential of garlic extract as a natural and sustainable approach to control crown gall in rose and tomato plants. The use of garlic extract could offer an environmentally friendly alternative to chemical pesticides, reducing the reliance on synthetic compounds in agriculture. Further research is warranted to optimize the application methods and concentrations of garlic extract for maximum efficacy and to elucidate the precise mechanisms by which garlic exerts its protective effects against crown gall. In conclusion, this study provides valuable insights into the potential of garlic extract as a novel strategy for managing crown gall disease in economically important crops like roses and tomatoes. By harnessing the natural defense mechanisms of plants, such as those found in garlic, sustainable solutions to plant diseases can be developed, contributing to the promotion of environmentally friendly agricultural practices.

Thesis Overview