Simplified soilless cultivation (SSC) systems have globally spread as growing solutions for low fertility soil regions, low availability of water irrigation, small areas and polluted environments. In the present study, four independent experiments were conducted for assessing the applicability of SSC in the northeast of Brazil (NE-Brazil) and the central dry zone of Myanmar (CDZ-Myanmar). In the first two experiments, the potentiality for lettuce crop production and water use efficiency (WUE) in an SSC system compared to traditional on-soil cultivation was addressed. Then, the definition of how main crop features (cultivar, nutrient solution concentration, system orientation and crop position) within the SSC system affect productivity was evidenced. The adoption of SSC improved yield (+35% and +72%, in NE-Brazil and CDZ-Myanmar) and WUE (7.7 and 2.7 times higher, in NE-Brazil and CDZ-Myanmar) as compared to traditional on-soil cultivation. In NE-Brazil, an eastern orientation of the system enabled achievement of higher yield for some selected lettuce cultivars. Furthermore, in both the considered contexts, a lower concentration of the nutrient solution (1.2 vs. 1.8 dS m⁻¹) and an upper plant position within the SSC system enabled achievement of higher yield and WUE. The experiments validate the applicability of SSC technologies for lettuce cultivation in tropical areas.

Postemergence application of herbicides can cause phytotoxicity problems in eucalyptus seedlings. Foliar fertilization can improve seedling development and mitigate the effects of herbicides on eucalyptus. Thus, the objective of this work was to evaluate the sensitivity of eucalyptus clones subjected to herbicides applied postemergence and associated with the application of foliar fertilizer. For this, a field experiment was carried out with the application of the products indaziflam, clomazone, glyphosate + S-metolachlor, sulfentrazone, and diuron + sulfentrazone, plus the application of an additional foliar fertilizer (composition in g/L of 78, 13, 40.3, 1.17, 0.78, 16.9, 13, 14.3, 0.52, and 29.9, respectively, for C, N, S, B, Co, Fe, Cu, Mn, Mo, and Zn). Height, stem diameter, shoot dry mass, chlorophyll content, and visual intoxication were the analyzed variables. The herbicides indaziflam and glyphosate + S-metolachlor were the most harmful to the tested eucalyptus clones, interfering with the growth variables. Among the evaluated clones, Clone AEC 144 had more significant changes in the analyzed variables in treatments with herbicides and foliar fertilizer application. The eucalyptus seedlings were generally more sensitive to indaziflam and glyphosate + S-metolachlor herbicides. Foliar fertilization reduced the intoxication caused by indaziflam in Clone AEC 056. The fertilizer intensified treatment symptoms with clomazone and diuron + sulfentrazone in Clone AEC 144 and with sulfentrazone and diuron + sulfentrazone in Clone AEC 2034.

Soil fauna is an important indicator of soil quality. This study aimed to evaluate soil fauna collected using pitfall traps and soil chemical and microbiological properties under different land uses in the Cerrado. The systems evaluated were soybean under 14-year no-till; soybean under 3-year no-till; eucalyptus rows; soybean grown between eucalyptus rows, and native Cerrado. Collected individuals were identified as classes, subclasses, order, or family classes. We evaluated the number of individuals trap ^-1 day ^-1 , total richness, average richness, Shannon Diversity Index, Pielou Evenness Index, total soil organic carbon (TOC), soil microbial activity, and soil chemical indicators. Data were submitted to one-way ANOVA, and means were compared by the Tukey Test (p<0.05). Principal component analysis and grouping analysis were performed among the groups and number of individuals. We identified 16 groups with a greater occurrence for Collembola, Acari, Formicidae, and Coleoptera. Systems containing threes provided a greater abundance of individuals. The largest populations occurred in the systems with the highest TOC levels. Components of the same silviagricultural system (soybean + eucalyptus) shared the same soil fauna groups, indicating a flow of individuals between these systems. The soybean adoption time under no-till systems does not change the population and diversity of soil fauna groups.

Limited chemical control options and high onion sensitivity to post-emergence herbicides hinder efficient weed management, especially under direct-seeding systems in semi-arid regions, increasing production costs. Reduced herbicide rates and split applications may improve crop selectivity while maintaining weed control. This study aimed to evaluate the selectivity of post-emergence herbicides applied at different doses and phenological stages in onion grown under Brazilian semi -arid conditions. Four field experiments were conducted in a randomized block design with three replications, each evaluating a single herbicide (oxyfluorfen, flumioxazin, pendimethalin, or oxadiazon). Fifteen treatments were evaluated, combining herbicide doses with three application timings (1-2, 3, and 5 fully expanded leaves), plus an untreated control. Crop injury was visually assessed at 7, 14, 21, and 28 days after application (DAA). Mild phytotoxicity symptoms (< 10%) were observed mainly at early growth stages, particularly when applications were performed at the 1- or 2-leaf stage, while treatments applied at more advanced stages (3 to 5 leaves) caused little or no injury. Symptoms were transient, with recovery observed by 21 DAA. Sequential applications occasionally prolonged low -intensity injury but did not exceed acceptable levels. No significant differences in commercial yield were detected among treatments. Bulb classification was predominantly concentrated in Class 3 (50-70 mm), with values generally above 60%, indicating high commercial quality and uniformity. The results demonstrate that the evaluated herbicides were selective for onion under semi-arid conditions when applied at appropriate doses and growth stages, with early stages being more sensitive and later stages more tolerant, without compromising yield or bulb quality.