In vitro cultivation of basil allows the manipulation of the concentration of certain micronutrients, commonly neglected by the micropropagation protocols. It is a plant of great economic importance for the cosmetic and pharmaceutical industry, due to the components present in its essential oil. In view of the above, the objective of this study was to evaluate zinc (Zn) concentrations in the micropropagation of basil, in addition to antioxidant activity and total phenolic compounds. Basil seeds, cultivars Manolo and Grecco Palla were oxygenated for 4 h, passed through asepsis and placed in test tubes with MS medium supplemented with 30 g L-1 sucrose and 6.5 g L-1 agar and pH adjusted to 5.8. The treatments were composed by the addition or not of 25 μM of zinc sulfate (ZnSO4) and arranged in a completely randomized design. The tubes containing the seeds and the culture medium were kept in a growth chamber for 90 days. The cultivar Manolo was more sensitive to the addition of ZnSO4 due to the increase in the number of leaves and in the antioxidant activity, however, the addition of this component in the culture medium did not influence the production of phenolic compounds or the activity of the antioxidant enzymes SOD, CAT and APX.

Elicitors of plant resistance are compounds that activate enzymatic processes involved in plant defense. Micronutrients also play an important role in plant responses against pathogens because they function as enzyme cofactors. Despite their well-known benefits, elicitors and micronutrients have been little investigated in nematode control. This study aimed to assess the effects of Agro-Mos® (a commercial biostimulant) and micronutrients (Zn and Mn), alone and combined, on soybean inoculated with Meloidogyne javanica. Seeds of soybean were sown in trays, treated 15 days after germination, and inoculated with 2000 eggs and juveniles of M. javanica at the time of transplanting. Treatments were as follows: 1 L/ha Agro-Mos®, 2 L/ha Metalosate® Zinc, 1.5 L/ha Metalosate® Manganese, Agro-Mos® + Zn, Agro-Mos® + Mn, and Agro-Mos® + Zn + Mn. Untreated inoculated and uninoculated plants were used as controls. At 60 days after inoculation, plants were harvested and evaluated for vegetative growth, nutrient content, and nematode parameters. All treatments were effective in reducing M. javanica population density in roots compared to the control. Agro-Mos®, Agro-Mos® + Zn, and Agro-Mos® + Zn + Mn were the most effective, reducing total nematode number and population density by 55–78% (P ≤ 0.05) in relation to the control. Agro-Mos® + Zn increased shoot dry weight. The results show that balanced fertilization can be used as part of an integrated nematode control strategy.

No abstract