The Valle Bonaerense del Río Colorado (VBRC) has proven to be agroclimatically suitable of strawberry production (Fragaria x ananassa Duch.). However, pathogenic soil fungi that affect this crop have been detected in the region, causing reductions in fruit production and plant death. The objective of this work was to evaluate alternative methods to methyl bromide (MB) for soil disinfection in strawberry cultivation and determine their effect on fruit production and plant survival in the VBRC. Three chemical methods were evaluated: the mixture 1,3-dichloropropene+chloropicrin (1,3-D:Pic), metam sodium and the mixture 1,3-D:Pic with subsequent applications of Trichoderma harzianumto the soil. The trial included the cultivars San Andreas and Sweet Ann and lasted two years. The fruit was classified as commercial and non-commercial, the number of dead plants was recorded according to treatments, and weekly monitoring of pests and diseases was carried out. In all treatments with chemical disinfection, plant survival in the second year was higher than soil without disinfection; however, no differences in yield were observed between treatments in either year. Inoculation with T. harzianum did not demonstrate beneficial effects on survival and fruit yield. The chemical methods evaluated, which could replace MB, would be appropriate to achieve greater plant survival in the second year of a biennial strawberry crop in the VBRC.

Spinach is characterized by having a high water content and different vitamins and minerals. However, this vegetable could have high oxalate and nitrate concentrations and can affect human health if consumed.The aim of this study was to evaluate the nitrogen fertilization effect on the yield, nitrate and oxalic acid content of spinach produced in an autumn-winter cycle under different growing systems. Spinach was grown in soil in a greenhouse and in an open field at the experimental field of the Faculty of Agronomy of the University of Buenos Aires. Soil treatments were 0.50 and 100 kg N.ha-1. Another culture was in substrate (perlite) where nitrogen supply restriction was applied 15 days before harvest. Color, leaf area, harvest index, yield, nitrate and oxalic acid levels were determined for each crop at harvest. Leaves were selected and 60 g were packaged in 31 micron polyolefin bags. Bags were stored in a refrigerated chamber at 5 ºC for 9 days. The nitrate and oxalic acid content of spinachwas also determined at the end of the storage period. Yield and leaf area were higher with 100 kg N.ha-1 without differences between greenhouse and open field. Oxalate content was higher in spinach from the open field, showing the highest value in the case of 100 kg N added, without changes at the end of postharvest period. The maximum nitrate content was 2.7 in greenhouse with 100 kg N.ha-1. The nitrogen restriction reduced the commercial yield, oxalic acid and nitrate content at harvest in perlite. The difference was maintained postharvest, except for the nitrate content.

The experiments were carried out in duplicate, on a farm located in the Piribebuy District, (25º 27' 28'' S; 56º 59' 12'' W and 95 masl), Cordillera, Paraguay, during the months of November to February between 2018 and 2019,with the objective of evaluating the effect of inoculation of a biological product based on Bradyrhizobium japonicum applied in seed treatment, on yield, number of root nodules and pod length, in Phaseolus vulgaris L. plants. An experimental design was applied in complete randomized blocks, with five treatments, consisting of the inoculant without the application of chemical fertilizer (T1), inoculant plus application of chemical fertilizer NPK 5-20-20 (T2), inoculant plus application of chemical fertilizer NPK 00-20-20 (T3), chemical fertilization NPK 5-20-20 without inoculant (T4), and a control without application of inoculant and fertilizer (T5). The data was processed through an Analysis of Variance (ANAVA), and to compare the means, a Tukey test was applied at 5% probability of error. The ANAVA indicated that the treatments were statistically different from each other. The highest values of yield, number of roots and pod length were recorded in the treatment with inoculant application and chemical fertilization with NPK 0-20-20.

Dill is used as a condiment in food and has medicinal properties. The objective of this work was to determine the optimum sowing date for growing dill in greenhouses for fresh cutting in San Pedro. The crop was established in an unheated greenhouse, located at the EEA San Pedro, INTA. Three sowing dates were carried out using two container sizes of 54 cm3 and 25 cm3 on days 2nd (T1 and T2) and 30th (T3 and T4) of March and 24th(T5 and T6) of April. Transplanting was carried out at a distance of 15 cm between rows and 20 cm between taps. At harvest, height and number of leaves per plant, number of plants per square meter and fresh weight were measured. Quality was determined based on a subjective scale from one to five, indicating lower to higher quality, respectively. Analysis of variance and Tukey's test (α=0.05) were performed. The highest plant height, number of leaves per plant, plants per square meter and fresh yield was achieved by T 5 (51.75 cm), T2 and T4 (8.48 leaves), T2 (58 plants) and T1 and T2 (4.37 and 4.12 kilograms per square meter), respectively. The optimum planting date was March 2nd with no differences between container sizes. With the management carried out, there were no limiting diseases for the crop.

The productive lifecycle of asparagus (Asparagus officinalis var. altilis L.) can exceed a decade, admitting the use of entirely male genotypes, with more uniform production than traditionally used dioecious. In order to study the productivity of seven Italian male genotypes of green asparagus (Italo, Zeno. Eros, Ercole, H-668, Marte and Giove) versus the American control (UC-157), a trial started in 2006 was evaluated at Chacra Experimental, Faculty of Agronomy - UNCPBA (36°48', lat.S-59°51', long.W). A total of 27 harvests were carried out in the period 09/18/2019–11/12/2019, quantifying total commercial fresh production (PFCT) and production by shoot length: : long (22 cm, PFC-L) and short (17 cm, PFC-C), in t.ha-1; Total number of shoots ( NTT) including total discard and commercial (NTCT), long and short (NTC-L and NTC-C) and unit weight (PPT-L), size distribution (J: Jumbo; XL: Extra-Large; L: Large; M: Medium; S: Small and A: Asparagine); discard (DE: spiked; MC: very short and OD: other defects) and response to foliar biological fertilizer (Arco-Plus, from Mycophos). Analysis of variance was performed with ANOVA-LSD test (P≥0.05). On average, the set of Italian genotypes exceeded 18% in t.ha-1,and 29% in NT, 13.5% in NTC-L, and 18.3% in NTC-C compared to the UC-157. In harvests, the following stood out: 18 and 19 (941,625a and 813,375a commercial shoots/ha, respectively), and the least productive were: 1-4 (average 729j). In shoots.ha-1, it was achieved, on average: NTT: 722562; NTCT: 403750; NTC-L: 225812 and NTC-C: 177938; while in t.ha-1: PFCT: 5.53; PFC-L: 3.4 and PFC-C: 2.12. The main defect was DE: 253125a shoots.ha-1. In PFCT, the following stood out: Ercole: 6.46ª; Giove: 6.03ab; Mars: 5.87ab; Eros: 5.55abc; H668: 5.47abc; Italian: 5.47abc); UC-157:4.76c and Zeno: 4.65c) t.ha-1. In PFC-L and PFT-C, Ercole stood out (4.02a and 2.43a t.ha-1 respectively). The favorable election of F was expressed in the variables: PFCT: 11%; NTC-L: 15%; NTC-C: 16%; and in the largest calibers (J: 11%; XL: 70% and L: 23%), therefore, the productivity of the Italian genotypes, especially Ercole, is encouraging.

Asparagus is a perennial vegetable, with an extensive productive stage and a progressive yield according to the age of the plantations; being the initial nursery stage determinant for the success of the crop and dependent on the starting system, management and quality of the seedlings. The objective of the study was to determine the effect of biofertilization (BF) on the growth of green asparagus seedlings (PEV) improving quality and implantation. An organic production trial was conducted (28/12/2021), in Tandil (Buenos Aires), using UC-157 genotype F2 and in pots. There were four treatments, a control without fertilization (T1), a fertilization treatment with arbuscular endomycorrhizae (T2-BRE), a fertilization treatment composed of micronutrients and plant hormones (T3-BFMH) and a combined fertilization treatment (T4-BRE+ BFMH). A heated greenhouse was used at the Faculty of Agronomy (UNCPBA) and a randomized block design with 3 replications, with weekly monitoring until the final size. Height (H) and number of stems (NT) were evaluated from 3/21/2022 to 5/31/2022. In the laboratory, fresh and dry weights of roots and stems (PFR-PFT-PSR-PST) were determined. Data were analyzed by ANOVA and LSD test (P≥0.05). The PFT and PFR in T4 were superior, finding no statistically significant differences in the biomass of stems and in PFR, surpassing T1, with T2 standing out with respect to T3 and T4. In summary, PEV BF increases biomass, mainly root biomass, constituting a valuable technique to achieve better plantations.

Onion (Allium cepaL.) is one of the main horticultural species in Argentina. The supply of seeds of this species is mainly from national production. Gibberellic acid (AG3) in onion is effective to induce flower buds when applied before or during the period of low temperatures.Throughout three seasons in La Consulta, Mendoza, Argentina, AG3 was tested to determine its effects on the seed production of onion cv Valcatorce INTA using the seed-to-seed method. The treatments were 0-200-400-600 mg.L-1 of AG3 in the first season and 0-300-600-900 mg.L-1 of AG3 in the other two; the plants were sprayed when they had between 5 and 7 leaves.The design was complete blocks with random plots and five replications. The number of umbels per plant, the seed yield per plant and unit area, and the seed quality, were determined. Gibberellic acid increased the number of umbels per plant.In the first two seasons, the highest seed yield per unit area was achieved with the use of the highest dose of AG3. However, in the third season, the best performance was obtained with 300 mg.L-1. The application of AG3 with the highest doses tested decreased the weight of a thousand seeds in two seasons without impairing germination.

One of the ways to grow basil (Ocimum basilicum L.) is in soil by transplanting, but there is little information on the production of seedlings. Therefore, the objective of this work was to evaluate the production of potted basil seedlings under a greenhouse with different substrates (pine bark compost and commercial substrate), irrigation systems (sub-irrigation and sprinkler) and fertilization doses (high:300N-87P-249K, medium: 150N-44P-125K and low: 75N-22P-62K).A trial of 12 treatments (2x2x3) and 20 repetitions was performed. Electrical conductivity (EC), pH and physical variables were measured for each substrate. At the end of the test, the dry mass (DM) of the stem, leaves, radical and aerial parts was measured. The commercial substrate had higher water retention capacity and less aeration than pine bark compost. The pH of both substrates was within the appropriate range and the E.C. at the maximum limit. At the end of the trial, in the treatments with sprinkler irrigation, the pH decreased and the EC increased. The seedlings obtained in the commercial substrate with low and medium doses had the highest DM of leaves and, together with those developed in the pine bark compost with low dose, they had the highest stem and root DM. Using sub-irrigation, the seedlings developed with commercial substrate (with the three doses) and with the lowest dose of pine bark compost presented the highest DM of leaves and roots. In conclusion, the seedlings produced by sub-irrigation systems in commercial substrate and with the three doses of fertilization, achieved the greatest development.

The cucumber is an economically important crop for the vegetables growers, especially in the Cordillera, Paraguay zone, due to the distance to the market and its appreciated value as food. The research was done in Colonia Curupayty, in the Cordillera department, in the Eusebio Ayala district, (latitude S 25° 22′ 54.34″ meridian W 56° 57′ 38.77″), Paraguay. The aim of this work was to evaluate cucumber crop yield(Cucumis sativusL.) applying different doses of boron (B), and were measured: yield of experimental unit (EU), fruit weigth, plant yield, fruit diameter and length and economic analysis. The experimental design was completely random, composed of four (4) treatments(T1: 0,5 lt/ha T2: 1,0 lt/ha; T3 1,5 lt/ha and T4 ( without boron) and five (5) repetitions.A liquid mineral fertilizer with boron ethanolamine was used, with a concentration of 11% boron.The crop was established in double files. The distance between plants was 1,0 m x 0,70 m. Variance analysis (ANAVA) and Tukey test at 5% demonstrated that boron influences cucumber production. The best results were for treatmentT3 (1,5 lt B/ha), with a yield/m2 of 11,90 kg, a fruit weight of 345 gr, yield per plant of 4,83 kg, fruit diameter with 4,6 cm and length of 26,02 cm.

The formulation of substrates for ornamental plants in containers implicates a compromise between physicochemical and biological characteristics, costs, andenvironmental impact for the use of peat. A way to optimize this relationship is by using local components. This work proposes the elaboration of a substrate based on Sphagnum peat and perlite, complemented with compost from regional agricultural residues as a possible replacement for a commercial substrate. The growth and development of Impatiens walleriana and Antirrhinum majus L. plants were compared in containers with different substrates: commercial (SC), peat/perlite 9/1 (TP), pure compost (C), and four TP/C mixtures (v:v): 8/2, 6/4, 4/6 and 2/8. The parameters evaluated in Impatiens walleriana were foliar area, number of flowers and accumulated biomass and in Antirrhinum majus L., plant height, nodes per plant, chlorophyll content (SPAD), estimated flowering percentage and accumulated biomass. A physicochemical characterization was carried out for the substrates, and it showed that the main limitation of incorporating compost is the increase of electric conductivity and pH, but with good management it is possible to increase its proportion in the mixtures. The TP/C 8/2 treatment obtained the best results among the mixtures, significantly exceeding the rest. No significant differences were found with the commercial substrate for most of the parameters measured in both ornamental species. The TP/C 8/2 treatment is the more economical and sustainable option due to the reduction in the use of peat and the recovery of wastes.