Effect of chemical treatment on physiological quality of seed and control of Meloidogyne javanica in watermelon plants

Abstract

This study aimed to evaluate the efficacy of different concentrations of abamectin, in combination with thiabendazole and thiamethoxam, on seed physiological quality and on the control of Meloidogyne javanica in watermelon plants. To this purpose watermelon seeds of the Crimson Sweet variety were employed in the study. The treatment of the seeds consisted of abamectin (nematicide) at concentrations of 0.075 g (ST 2 ), 0.150 g (ST 3 ), 0.300g (ST 4 ) and 0.600 g (ST 5 ) ai (active ingredients) per 1000 seeds in combination with thiabendazole and thiamethoxam at concentrations of 0.080 g, 0,019 g ai per 1000 seeds, respectively. Untreated seeds (ST 1 ) were also employed as a control. The volume of the mixed solution used to this purpose was 4.9 mL 1000 seed -1 . The untreated and treated seeds were divided in two parts; the first part was sowed on paper towels and placed in chambers maintained at a constant 25 ºC while the second part was planted in trays in a greenhouse so as to enable evaluation of shoot length, shoot fresh weight, root weight, galls number, egg number, and reproduction factor. The physiological quality of the seeds was evaluated by standard germination tests, cold tests, and emergence speed index. The results indicated that the watermelon seed quality was not affected by concentration of abamectin when used in combination with thiabendazole and thiamethoxam. Further investigations are warranted in order to verify nematicidal toxicity on seed quality at higher levels of treatment. Based on the results of our study, we propose that abamectin (0.75 to 600 g/ ai per 1000 seeds) when applied in combination with thiabendazole and thiamethoxam, is an effective control agent for reducing the number of eggs and second-stage juveniles (J2) in 'Crimson Sweet' watermelon plants.

The effect of abamectin seeds treatment on plant growth and the infection of root-knot nematode Meloidogyne incognita (Kofoid and White) chitwood

“… da Silva et al (2017) decided that maize seed treatments with abamectin significantly improved most root development variables and abamectin had a large positive effect on seedling health. Rodrigues et al (2017) reported that the quality of the seeds of the watermelon is not affected by the concentration of abamectin when used in 0.75 g up to 600 g/ ai (active ingredients) per 1000 seeds. Hnoosh and Aljuaifari (2020) showed that the okra seeds when treated with abamectin ( Streptomyces avermitilis ) were significantly improved compared to non-treated seeds.…”