Managing major diseases of tomato (Solanum lycopersicum L.) using resistance elicitors and protected cultivation

Abstract

Diseases, particularly bacterial wilt caused by Ralstonia solanacearum is a major constraint to vegetable production. Protected cultivation has been proven effective in reducing disease incidence but additional control measures need to be integrated in highly infested soils to mitigate the losses due to diseases. This paper reports the effect of resistance elicitors, particularly chitosan, acetylsalicylic acid and SiO2 in mitigating bacterial wilt disease problem and other naturally occurring diseases in two field trials. Two hundred ppm chitosan, acetylsalicylic acid and their combination had reduced bacterial wilt incidence and increased the yield of tomato under protected cultivation, but not in the open field. SiO2 was not able to reduce bacterial wilt incidence in tomato but had reduced the nematode count, especially Rotylenchulus sp. in the roots, particularly when drenched. Protected cultivation still proved effective in reducing bacterial wilt incidence in both experiments. It’s potential to protect crops against bacterial wilt is further enhanced by the application of chitosan and acetylsalicylic acid, most especially the combination of these treatments. The potential of chitosan and acetylsalicylic acid in protecting plants in the open field against bacterial wilt may be enhanced by the addition of a sticker.