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.

This research was carried out in the city of Asunción Central Department - Paraguay in the Mburukuya neighborhood, whose georeferenced coordinate is 25°18'00'S 57°38'00''W . The objective of the work was to evaluate the effect of a biostimulant on the yield of the lettuce cv. ‘Verenada’ in a hydroponic system. The experimental design used was completely random and had three treatments and four repetitions with a total of 120 plants per treatment. It was concluded that there is an influence with the use of biostimulant on the variables studied. Regarding the height and weight of the plant, the treatments T1 (one application) and T2 (two applications) were the ones that presented the highest values. Treatment T1 (one application) presented a greater number of lettuce plant leaves. Regarding root weight, there was no statistical difference between treatments.

Homeopathic treatments influence growth, production of secondary metabolites, essential oil yield, phytochemical profile, and tolerance to salt stress, among others, when applied to various crops. Homeopathic ultra high dilution is used safely for various purposes (seed germination, soil health improvement, seedling growth, flowering, fruiting, disease protection and to overcome environmental stress). Proper selection of Homeopathy medicament for each case is very important, to have hight efficiency and profitability. The agrohomeopathy can increase farmers' income by reducing the cost of use chemical fertilizers and insecticides. Literature articles on research related to the use of homeopathic preparations in plant cultivation were collected. Their impact on growth, yield, essential oil composition and tolerance to salt stress was emphasized. Various publications in which homeopathy was applied to various crops and its use increased crop yield, production of secondary metabolites (coumarins, alkaloids, phenylpropanoids), absorption and growth of nutrients in medicinal plant species, as well as tolerance to saline stress. Therapeutic treatments for human and animal health are shown to be important for various plant crops. The application of homeopathic preparations is an alternative for plant growth, friendly to the environment. It is also affordable for farmers and researchers, however more studies are required to improve its influence and effects.

Onion seed represents a high percentage of the total economic value of vegetable seeds marketed worldwide. In Argentina, onion seed production is carried out in San Juan and Mendoza, where open-pollination (OP) cultivars and first generation hybrids are used. An OP variety has good seed yield, but the yield of hybrid seeds is erratic and considerably lower. Seed yield and quality depends, among other factors, on fertilization. Nutrients such as boron, zinc and calcium are essential for the growth and development of plants. Foliar fertilization allows the supply of nutrients to specific organs when the growth stage, internal demand and environmental conditions limit their delivery. The objective of this study was to evaluate the effect of the foliar application of boron, zinc and calcium, on the yield and quality of onion seed. The study was conducted on cv. Angaco INTA in a commercial farm located in the department of Pocito, San Juan. A completely randomized design with four replications was used. Three doses of boron, calcium and zinc, plus a combination of the three nutrients and the control were evaluated. The foliar application of boron, both simple and combined with zinc and calcium, produces a greater fruit set, while calcium improves germination. No significant effects on seed yield were observed.

The soils cultivated under cover deteriorate due to irrigation with saline waters, excessive fertilization, limited drainage and absence of leaching of salts by rain. The objectives of the work were to forecast leaching water depth, recover a salinized soil by hydro improvement method, maintain the tolerable soil salinity by the lettuce crop applying the leaching requirement and evaluate the saline dynamics of the soil cultivated and irrigated with the Balansal model. In a greenhouse drain tubes were buried at 50 cm spaced every 2 m and 0.2 m3 tanks were installed at the discharge. The leaching water depth was predicted using 6 mathematical models and into basins of 10 m2, the initial and residual electrical conductivities of the soil and drained water were measured after applying 3 water depths, totalling 320 mm. The main results were: the predicted leaching water depth averaged 320 mm; the average initial soil salinity of 4.69 dS.m-1 was reduced to 0.81 dS.m-1 after the last leach; the salts decrease of the first leaching with respect to the initial salinity was 74.1%, that of the second leaching was 31% and that of the third leaching was 3.7%; the salinity of the drained water was 0.97 dS.m-1; 0.91 dS.m-1 and 0.88 dS.m-1 after each leach, respectively. With the application of a leaching requirement of 15%, the soil salinity was maintained at 0.87 dS.m-1 and the Balansal model predicted with good adjustment the saline dynamics of the soil during the crop cycle.

Argentina, one of the main South American strawberry (Fragaria x ananassa) producers, shows an increasing trend to reduce the use of agrochemicals (pesticides and fertilizers), and incorporate bio-inputs. In this context, the objective of this work was to evaluate the effect of MO.14 (a liquid organic amendment, rich in humic and fulvic acids), applied alone or combined with a biological activator (Biomix), on the yield and fruit quality of four strawberry cultivars. A trial was carried out in the 2016 productive season and part of 2017, in Famaillá (Tucumán). Treatments: MO.14 (drench), MO.14 (drench) + Biomix (foliar) and untreated control (T). Cultivars: Benicia, Camino Real, Merced and San Andreas. Yield (total fruit weight/plant, Yld), number of fruits/plant (NF), marketable fruit average weight (MFAW) and percentage of rotten fruits (%RF) were evaluated. Experimental design: CRD with three replications of 30 plants per cultivar and treatment. Data were subjected to ANOVA. Treatments improved Yld and NF, but not %RF and MFAW (genotypic effects prevailed). MO.14 showed Yld and NF values higher than MO.14 + Biomix. Treatment-cultivar interactions were significant for NF. Regarding the cultivars, Merced stood out (Yld, MFAW). In May 2017, when the first harvests of the 2nd year started, biostimulants exceeded T in Yld. Biostimulant treatments could reduce the use of chemical fertilizers in strawberry, contributing to agroecosystem sustainability, although new studies (dose, concentration, number of applications) should validate that.

Viral diseases can affect the stability of common bean (Phaseolus vulgaris L.) production, therefore it was considered of interest to evaluate the behavior of different cultivars and promising lines obtained by the INTA breeding program against natural virus infection. Symptoms severity, incidence and relative concentration of Cucumber mosaic virus (CMV), Cowpea mild mottle virus (CpMMV), Alfalfa mosaic virus (AMV), Soybean mosaic virus (SMV) and geminiviruses were evaluated for 14 bean cultivars during three growing seasons. SMV and AMV were found in very low incidence during the three years. Differences in cultivar response were observed: L24 and L15 were tolerant to begomoviruses, while CR8, CR5, L22 (cranberry and white bean types) were susceptible. The most severe symptoms were found during the 2013 growing season, when a high incidence of begomovirus and CpMMV were observed. No differences between cultivars were found for CpMMV incidence, but a higher relative concentration of virus was detected in CR5, CR8 and L17. Although L15 was tolerant to geminiviruses, it was the most susceptible to CMV, a fact that must be taken into account because this virus is transmitted by seeds and might become a serious problem in bean production.

Data analysis of vegetables cultivars registered in the National Registry of Cultivars (RNC) and the Registry of Cultivar Property (RNPC) of Argentine, allows to estimate the economic importance of each species. In addition, it could be considered as an indicator of   the dynamics of the work of improvement and development of new cultivars from both Argentina and abroad. The objective was to analyze the evolution of the registration of vegetables cultivars in the RNC under the point of view of the amount, the genetic condition, the origin and, the property origin between 2000/01/01 and 2015/12/31. The basic data was obtained from the National Catalogue of Varieties from the website of the National Institute of Seeds (INASE). Over 66 categories, combination of species and genetic condition (hybrid or variety) 3,057 cultivars were registered up to December of 2015. That depicts an increase of 122 % respect to January 2000. The 95% of the cultivars were registered into 31 categories until 31/12/2015. Furthermore, 1,585 new cultivars were registered between 2000 and 2015. From this total 1,478 were foreign cultivars and 94 national cultivars. Foreign cultivars came mainly from U.S.A. (38.4 %) and the Netherlands (28.5 %). The hybrid cultivars totalized 1,072 (67.6%) and, among them hybrid tomato registered the highest number of entries (495) followed by hybrid pepper (163).  

The richness of cultural values found in Argentinean Andean communities is reflected by resource diversity and ancestral crop management practices. Traditional landraces are highly appreciated for their flavour, colour and aromas. However, social, economic and environmental factors have an effect on crop diversity conservation. In this context, germplasm recuperation and conservation is a priority. The objectives of this work was to recover a representative collection of autochthonous crop genetic resources still cultivated in Andean valleys of Argentina, tomato in particular, analyze its distribution, and document farmers’ crop experiences and uses. One hundred and thirty families were interviewed, and they donated a total of 561 samples of landraces belonging to 41 species, including 29 tomato samples. The landraces collected shows a geometric distribution, typical in communities with low number of species; and a pattern of dominance, showing that common species are present in almost all farms while rare species are found in specific environments. Traditional agriculture is a familiar economic activity, mainly affected by environmental factors. Local germplasm recover could prevent genetic erosion and help to link in situ and ex situ conservation in a more efficient way, consequently both the formal breeding sector and farmers can use the diversity of the collections for their crop-improvement efforts.

In the northwest of Corrientes province, Argentina, an intercropping field experiment was conducted in the Experimental Field of the Agronomy Faculty of the Northestern National University (27º 28’ S; 58º 16’ W). Plant productivity, economical profit and the land use equivalent (LUE) of four species, cassava-maize-peanut-cowpea, intercropped in three different plantation densities, were compared respect to their monocropping system planted in convencional densities. Seven treatments (four monocroppings and three intercroppings with different densities), were arranged in a complete randomized block design replicated four times. Yield results were studied by variance analysis and by Duncan test (P < 0.05). The best yields, as well as the high economical profit and the best LUE among the intercropping systems were asociated with the highest planting density (Cassava 5.000 plants·ha-1 - Peanut 25.000 plants·ha-1 - Cowpea 20.000 plants·ha-1 - Maize 20.000 plants·ha-1), corresponding to treatment 5. Particulary the intercropping treatment with the highest planting density was the most appropriated system for the agroecologycal NEA conditions.