IOSR Journal of Agriculture and Veterinary Science (IOSR-JAVS) e-ISSN: 2319-2380, p-ISSN: 2319-2372. Volume 12, Issue 6 Ser. I (June 2019), PP 37-46 www.iosrjournals.org DOI: 10.9790/2380-1206013746 www.iosrjournals.org 37 | Page Productivity and Level of Weeding Level in Bean Cultivars in Response to Spacing between Rows Adolfo Leguizamón Resquin 1* , Carlos Mongelos 1 , Hugo Rodríguez 1 , Eulalio Morel 1 , Edhit Ruiz Díaz 1 , Marcos Sánchez 1 and Oscar Caballero 1 1 (Concepción, Universidad Nacional de Concepción, Paraguay) *Corresponding author: Adolfo Leguizamón Resquin Abstract: In Paraguay, the bean can become a good option for agricultural diversification, for commercial purposes and for this, changes must be made in the productive system of this item. Based on this, this work was developed, between September and October 2015, with the purpose of evaluating productivity and weeding level of cultivars of bean in response to the spacing between rows. The experimental design used was randomized complete blocks, with an arrangement of subdivided plots 2 x 4, the main plot being the cultivar(Negro and Carioca) and the secondary plot, the spacing between rows (30, 40, 50 and 60 cm ), with four repetitions. The number of pods per plant, total yield and weight of 1000 grains, fresh mass and dry weed mass per m2 were determined. The data obtained were subjected to analysis of variance and comparison of means by the Tukey test and regression analysis. The cultivar Carioca was superior to the Negro in the productive characters; the increase in spacing between rows induced lower values of the bean performance as well as the other productive components. There was an increase in the level of weeding by increasing the spacing between plants. Keywords: Phaseolus vulgaris, weeds, spacing, productivity --------------------------------------------------------------------------------------------------------------------------------------- Date of Submission: 25-05-2019 Date of acceptance: 10-06-2019 --------------------------------------------------------------------------------------------------------------------------------------------------- I. Introduction The production of bean in Paraguay in the period 2012/2013 was of 3.769.000 kg, with a sowed surface of 4.547 hectares and an average yield of 828.89 kg.ha -1 and it is concentrated in the Departments of San Pedro, Concepción , Canindeyú and Amambay (DGEEC, 2015). Its cultivation is approached at the level of small producers and is intended for family consumption (Schulz, 2006), but it can nevertheless become a good option for agricultural diversification, for marketing purposes. For this, changes must be made in the productive system of this item, and within these, one of the aspects that can be modified refers to the spacing of the crop, since the distance of 0.60 m between rows and 0.25 m between plants recommended by the Ministry of Agriculture and Livestock (Schulz, 2006), results in a low plant density (66,667 pl.ha -1 ) in relation to that used in other countries, mainly Brazil, where a density of 200,000 is recommended pl.ha -1 (CTSBF, 2012). With the increase of planting density it is expected that the productivity of the crop increases and this response reaches the maximum when the point of maximum technical efficiency is reached: the critical density that allows to reach the maximum productivity and above which the yields they are decreasing. This density varies with the cultivar and the region, so for each case studies must be conducted in order to determine the exact relationship for each particular situation. By varying the planting density, other aspects of production are also influenced, such as the level of weeding, which can directly influence production costs, since the quantity of hand weeded control or other operations for weed control can be modified. Based on the presented approaches, this work was developed with the purpose of evaluating the effect of the spacing between rows on the productivity and the level of weeding of cultivars of bean, based on the following objectives: to determine the number of pods per plant, the total yield of the crop and the weight of 1000 grains of cultivars of bean in function to the spacing between rows. To evaluate the influence of the treatments on the number, fresh mass and dry mass of weeds in the cultivation of bean.