Despite the wide distribution of Spondias purpurea L. across tropical America, its fruit remains relatively unknown and is consumed mostly regionally; this is largely because several aspects of its postharvest quality and physiology remain unknown. The objective of this work was to address these issues in three variants of S. purpurea L. (Roja, Morada, and Amarilla) and to propose improvements to their postharvest management and conservation. For this, fruit from each variant was harvested at ½ and ¾ maturity, stored at 25 ± 2 °C (60 % relative humidity), and evaluated according to several physical, chemical, and physiological parameters. Weight loss, respiration, and ethylene production were highest in Roja; however, postharvest life was the shortest (5-6 d). Firmness was highest in Morada, while respiration and postharvest life were the lowest and longest (6-8 d), respectively. During ripening, total soluble solids and titratable acidity increased in all three varieties, though they did so to a much lesser extent in Amarilla. Total phenolics increased in Roja and Morada during the first stage of ripening (d 2-4) while flavonoids only did so during the second stage. In Amarilla, however, the levels of both remained relatively low. FRAP-determined antioxidant activity was therefore higher in the first two which, together with all other results, indicate important differences in the quality of these variants of S. purpurea L., and thus, in the resulting management and conservation strategies.

Tomato is infected by more than 100 pathogens that affect its production; therefore, it is crucial that commercial varieties integrate resistance genes. In this context, molecular markers improve the efficiency of the selection process. This study aimed to validate the efficacy of molecular markers in identifying genes resistant to six pathogens: Meloidogyne sp. (Mi-1 and Mi-1.2), Fusarium oxysporum f. sp. lycopersici (I-1 and I-2), Stemphyllium sp. (Sm), Phytophthora infestans (Ph3), tomato yellow leaf curl virus (Ty-2 and Ty-3) and spotted wilt virus (Sw5b). Protocols for 10 pairs of markers associated with resistance genes were adapted and tested on 20 genotypes. Pathogen resistance genes were identified in 17 advanced lines and three commercial hybrids of tomato. Molecular markers distinguished lines with resistance genes to six important diseases in tomato cultivation, which could therefore be used for the development of new varieties.

Sulfentrazone is one of the main pre-emergent herbicides used in tobacco plantations. The objective of this work was to evaluate the selectivity and efficiency of sulfentrazone-based formulations in two tobacco production systems (conventional tillage system [CTS] and no-tillage system [NTS]). Two experiments were conducted (CTS and NTS) in a randomized block design, with seven treatments and four replications. The herbicide treatments were: T1 = Boral® 500 SC (400 g∙ha^-1 of sulfentrazone), T2 = PonteiroBR® (400 g∙ha^-1 of sulfentrazone), T3 = Stone® (350 + 700 g∙ha^-1 of sulfentrazone and diuron, respectively), T4 = Boral® 500 SC + Gamit® 360 CS (792 g∙ha^-1 of clomazone), T5 = PonteiroBR® + Gamit® 360 CS, T6 = Stone® + Gamit® 360 CS, and T7 = control (manual weeding). Phytotoxicity in tobacco plants and weed control efficiency were visually evaluated 14, 28, 42, and 56 days after application (daa) of the treatments. Emerged weed plants per m2 were counted 56 daa. Tobacco yield was evaluated by determining the yield per third of the plant (lower, middle, and upper thirds) and the total yield (sum of the yields from each third). The sulfentrazone formulations were efficient in weed control. The herbicide Stone® applied alone or mixed with Gamit® caused mild phytotoxicity in plants under NTS, but no yield losses. No significant difference was found in yield among treatments; however, the yield of the upper third of the plant was higher for plants under NTS, affecting the total yield. The sulfentrazone formulations used provided efficient weed control and selectivity to tobacco plants. The use of NTS resulted in higher yields.

Current agriculture faces challenges caused by climate change, which induce states of stress in plants, reducing crop productivity. Micro- or nanomaterials are biostimulants that mitigate these adverse effects, having greater efficiency compared to conventional materials. Iodine, at low concentrations, improves plant growth and production. This study aimed to: 1) synthesize and characterize polymeric particles functionalized with submicron iodine (PI), 2) evaluate the impact of pretreatment of corn seeds with these particles on the germination rate and growth of the seedlings, and 3) quantify the iodine in the PI and in the seedlings. The synthesis of the PI was carried out by a chemical reaction from iohexol with a crosslinker and the addition of a polyethylene glycol coating. The average hydrodynamic diameter of the PIs determined by dynamic light scattering was 217 nm, and the iodine content in the synthesized PIs was 1.67 %. For the germination test, four PI concentrations (5, 10, 20, and 50 mg∙L^-1) and a control (distilled water) were used; 50 seeds were imbibed in 10 mL of each solution and placed in a growth chamber at a temperature of 28 °C for 24 h. The results indicate that PIs do not negatively interfere with the seed germination process and the treatment with a concentration of 50 mg∙L^-1 PI significantly favored some growth variables. The latter indicates that the synthesized PIs presented a biostimulant effect and may be a viable alternative as a biofortifier.