Jambu is a leafy vegetable with enormous versatility, showing potential for fresh food and industrial exploitation due to the biosynthesis of spilanthol. The aim was to evaluate the biostimulant potential of Trichoderma spp. in promoting growth, yield, and spilanthol content in varieties of jambu. For that purpose, we conducted an experiment divided into two trials. We used a randomized block design arranged in a 3 & times;4+3 factorial scheme, with four replications, in which the treatments consisted of the combination of jambu varieties (first factor) and biostimulants (second factor), plus three additional treatments (without inoculation). Plant height, stem diameter, and number of leaves were assessed at the seedling stage. In the field, flowering, leaf gas exchange, vegetative development, biomass production, and spilanthol content were assessed. Jamb03-MIX seedlings showed higher plant height and stem diameter. The leaf gas exchange showed the highest values in Jamb-16 with and without biostimulant. Jamb17-MIX presented earlier flowering. The growth and yield of the shoot were superior for Jamb16-IBLF006 and Jamb16-MIX, influencing the grouping. Principal component analysis separated Jamb-03 based on inflorescence yield and internal CO2 concentration. Jamb03-MIX had higher inflorescence production than the other varieties biostimulated with MIX. The content of spilanthol in the inflorescences of Jamb17-MIX (39.24 mg/g DM) was influenced by biostimulation when compared to Jamb17-Ad (31.64 mg/g DM). However, the compound did not respond in Jamb-03 and Jamb-16. Therefore, the inoculation of Trichoderma spp. in jambu promotes the development of more vigorous seedlings, early flowering, and biomass accumulation and modulates the biosynthesis of spilanthol, but the specificity of the Trichoderma variety interaction conditioned the results.
Currently, commercial palm heart production is based on intensive cultivation, due to the introduction of new palm species and technological improvements. Thus, the objective was to evaluate the agronomic potential of species of the genus Roystonea in high-density planting for the production of palm heart. The experimental design was randomized block in a 4 x 2 factorial scheme, 4 replications, 30 plants per plot and a useful area of twelve plants. The factors were four species: Roystonea altissima, R. oleracea, R. regia and R. borinqueana and two spacings: 2.0 x 0.75 m and 2.0 x 0.50 m. Growth parameters were evaluated every 3 months and palm heart production at 24 months. The four Roystonea species showed rapid growth with satisfactory palm heart production at 24 months. R. altissima showed the highest values for height and diameter, variables highly correlated with palm heart production. The stem diameter values from 18 months onwards and the decrease in the diameter growth rate suggest that the harvest may be brought forward. Both planting densities promoted satisfactory yields, with higher palm heart production per area at the 2 x 0.50 m spacing.
ABSTRACT Herbicide selectivity in cassava is essential for effective pre-emergence weed management. However, the limited number of registered products restricts available options. This study aimed to evaluate the efficacy and selectivity of pre-emergence herbicides applied using the plant-and-apply system for weed control in cassava. A field experiment was conducted with the IPR Paraguainha variety in a randomized block design with four replications. Treatments included ametryn; clomazone; flumioxazin; s-metolachlor; pyroxasulfone; isoxaflutol; metribuzin; diuron; metribuzin + s-metolachlor; ametryn + clomazone; pyroxasulfone + flumioxazin; flumioxazin + s-metolachlor; sulfentrazone; and two controls (control and weeded control). Evaluations included crop phytotoxicity, plant height, stem diameter, chlorophyll content, and weed control. After ten months, yield, starch content, and root length and diameter were assessed. Sulfentrazone caused phytotoxicity above 20%. S-metolachlor alone provided only 30% weed control. Ametryn and ametryn + clomazone resulted in more than 80% and 90% weed control, respectively. For ametryn, root yield exceeded 28 t/ha. Among herbicides commonly used in soybean, metribuzin and flumioxazin + s-metolachlor showed effective weed suppression, demonstrating their potential as viable options for cassava production.
This study evaluated the effects of growing media and fertilizer applications on greenhouse strawberry cultivars 'Pharachatan 80' and 'US Jumbo' using a 4 & times; 3 factorial in CRD with five replications. Growing media comprised sand (S), coconut coir dust (C), and cow manure (M) in varying ratios (1:1, 1:1:1, 1:1:2, and 1:1:3 v/v), paired with no chemical fertilizer (NCF), a half-recommended dose (& half; RDCF), or a full recommended dose of chemical fertilizer (RDCF). Results revealed that unamended substrate (S:C = 1:1 v/v) under NCF severely constrained crop performance. Conversely, integrating cow manure with chemical fertilizers significantly enhanced vegetative growth and yield attributes. Specifically, S:C:M 1:1:1 v/v combined with & half; RDCF optimized total marketable yield, increased the proportion of Grade 2-4 fruits, and improved fruit quality across both cultivars. However, elevated temperatures in tropical lowland greenhouses constrained fruit enlargement, resulting in >= 70% Low-Grade fruits (<7.0 g). Correlation and principal component analyses confirmed that balanced root-zone management mitigates severe nutrient stress. Overall, S:C:M 1:1:1 v/v with & half; RDCF represents the most effective strategy for tropical greenhouse strawberry cultivation, although implementing microclimate cooling or exogenous biostimulants remains necessary to overcome high-temperature limitations.
Highlights What are the main findings? What are the implications of the main findings?Highlights What are the main findings? What are the implications of the main findings?Abstract The mycelium of Phallus rubrovolvatus contains abundant metabolites with broad application prospects in functional foods and pharmaceuticals. However, how carbon and nitrogen substrate availability regulate the accumulation dynamics of mycelial metabolites remains under-explored. In this study, the supply levels of carbon (glucose) and nitrogen (peptone) were optimized to select high-biomass mycelia. Integrating nutritional activity assays with metabolomics and redundancy analysis, the regulatory mechanisms governing carbon-nitrogen metabolic flux were deciphered. The results demonstrated that mycelial nutritional content and antioxidant capacity exhibited a progressive upward trend under three distinct modes: carbon-driven, nitrogen-driven, and carbon-nitrogen synergistic-driven regimes. In the optimal carbon-nitrogen synergistic-driven group, the contents of total soluble sugars, reducing sugars, flavonoids, total phenolics, and soluble proteins increased by 72.06%, 160.80%, 52.47%, 113.69%, and 8.21%, respectively, compared with the control group. Meanwhile, the scavenging rates of superoxide anion, hydroxyl, ABTS, and DPPH free radicals increased by 14.12%, 24.09%, 14.77%, and 66.47%, respectively, compared with the control group. Differentially accumulated metabolites were significantly enriched in amino acid metabolism, energy metabolism, and secondary metabolite biosynthesis pathways. Carbon and nitrogen substrates reshaped intracellular metabolic flux, cooperatively regulating nutrient synthesis and intracellular redox equilibrium. This work reveals a cascade-linking relationship in which nutrient supply triggers metabolic remodeling, regulates oxidative balance, and drives pathway response. It provides theoretical support for the precision fermentation and industrial upgrade of P. rubrovolvatus, while offering a valuable reference paradigm for the high-value exploitation of other rare edible and medicinal fungi.
