Distância mínima da linha de semeadura da soja em relação ao ramo ortotrópico do cafeeiro em formação

Abstract

The use of soybeans between coffee plants can alter the vegetative and productive growth of the main crop. Therefore, the objective of the present work was to define the minimum distance of the soybean sowing line in relation to the orthotropic branch of the coffee tree in formation based on the evaluation of morphological and biometric parameters. The experiment was carried out in the demonstration area of the Federal University of Uberlândia, Campus Monte Carmelo, Minas Gerais. The geographical coordinates of the experimental area are 18° 43' 36'' S and 47° 31' 23'' W, located at an altitude of 898 m. The coffee tree was planted in March 2021, with a spacing of 3.5 m between rows and 0.6 m between plants, using the IPR 100 cultivar. The planting of soybeans between the coffee rows was carried out in November 2021, using the cultivar LG 60162IPRO, with a spacing of 0.4 m between rows and 14 seeds per linear meter. The coffee plant was irrigated using a drip system, with a spacing between the drippers of 0.6 m and a flow rate of 2.1 L h-1. The soybeans grown between the coffee rows were not irrigated. The experimental design used was in randomized blocks, with four blocks and five treatments, namely: (TI) without soybeans, (T2) 2 soybean lines, 1.55 m apart from the coffee tree stem, (T3) 4 lines of soybeans, spaced 1.15 m from the coffee tree stem, (T4) 6 soybean rows, 0.75 m distance from the coffee tree stem and (T5) 8 soybean rows, 0.35 m distance from the coffee tree stem . Each plot was composed of 5 coffee plants, 3 m long and 3.5 m wide. The following characteristics were evaluated: length, width and thickness of two leaves per plant, chlorophyll (SPAD 502), leaf temperature, stomata count, and length of a pair of plagiotropic branches located in the middle third of the coffee tree, number and distance of internodes and number of primary plagiotropic branches. The data were subjected to analysis of variance and, if significant differences were detected, the means were compared using the Scott-Knott test. The use of soybean between the coffee trees did not affect the growth and morphological characteristics of Coffea arabica L, with the exception of the leaf width parameter, in which this characteristic increased with the increase in the population of soybean plants.