Growth and yield of maize intercropped with different species of brachiaria, in Piracicaba, SP.

Author(s)

Guy Mitsuyuki Tsumanuma

• Document type: Master's Dissertation
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC)
• Defense date: 2005-01-17

Examining board members

Antonio Luiz Fancelli; Artur Chinelato de Camargo; Jose Laercio Favarin

• Advisor: Antonio Luiz Fancelli

Abstract

Maize intercropped with grass can be used both to pasture renewals and to quality and longevity of soil cover formation in no-tillage system. The present work aimed at evaluating the interactions and interferences of different brachiaria species on maize yield, as well as determining which would be the most appropriate species for a intercropping system. The experiment was carried out in Piracicaba, São Paulo State, Brazil (Universidade de São Paulo, ESALQ), in a typical Rhodudalf soil, under central pivot, in an experimental area belonging to the Department of Crop Production. The experimental design was in randomized blocks with seven treatments and four replications. The treatments consisted of a combination of three brachiaria species (Brachiaria decumbens, Brachiaria brizantha and Brachiaria ruziziensis) sowed in two different dates (together with maize and when maize had four fully expanded leaves), as well as a control treatment (single maize). In relation to maize, the results showed no statistical differences among the treatments for the following parameters: plant height; leaf area index; stem diameter; foliar analysis; number of grain rows; number of grain per rows in ear; thousand grain weight and productivity. However, the number of maize leaves and the sanity of ears were affected by the treatments. Thus, treatment 6 (B. brizantha sowed at the four leaves stage of maize) favored larger number of leaves on maize plants, and B. decumbens sowed on the same dates as maize presented lower rate of deteriorated grains per spike in comparison to the control treatment. In relation to brachiaria, all of the species sowed on the first date (concomitant sowing with maize) differed from those sowed at the four leaves stage of maize, for green and dry mass production. The B. decumbens and B. brizantha, sowed in the first time, presented larger production of root dry matter in comparison to B. brizantha, sowed on the second date. After cutting, the green and dry mass production of shoot of B. decumbens and B. brizantha sowed on the first date was superior to the green and dry mass production of B. ruziziensis sowed on the second date. B. decumbens, regardless of the sowing date, presented a greater suppressor effect on weeds. The analysis and the interpretation of the results allowed to conclude that the presence of brachiaria, regardless of sowing date, doesn't affect the development and the productivity of maize, thus demonstrating the technical viability of intercropped systems of production. However, the presence of maize negatively influences the biomass accumulation of brachiaria, especially, when these are sowed when maize has four leaves. For pasture formation, the studied forage grasses present better yield and productivity when sowed at the same date as maize. Among the brachiaria, B. decumbens stands out for the amount of forage produced, as well as for the suppressor effect on weeds. However, for forage production, B. brizantha presents similar results to B. decumbens. (AU)