Sprouting of pre-sprouted sugarcane seedlings and micrometeorological variables under photo-selective nets

Abstract

Sugarcane is a grass species that stands out worldwide in the production of ethanol. Brazil is the world's largest producer and leader in exports, responsible for more than 50% of the products that are marketed worldwide. The objective of this study was to investigate the effect of photo-selective nets on micrometeorological variables and on sprouting of pre-sprouted sugarcane seedlings. The experiment was carried out in a protected environment at Universidade Federal Rural de Pernambuco -UFRPE, in a completely randomized design. Seedlings of cultivar RB92579 were obtained by the technique of production of pre-sprouted seedlings. The protected environment was divided into four modules corresponding to the treatments: covered with anti-UV low-density polyethylene plastic: + Solpack ® red ultranet net, + Solpack ® white net, + Solpack ® freshnet net and without shade net. Micrometeorological data of air temperature and substrate temperature were recorded in each module. The first count of emergence, sprouting speed index and sprouting percentage were calculated. Principal component analysis was used to verify the association between the cultivation modules and the micrometeorological and sprouting variables of the seedlings. Air temperature in the protected environment was 8.7% higher than that in the external environment. The white net led to sprouting of 78.93%. The substrate temperature above 30.4 °C favored seedling sprouting. The modules with white net and red ultranet net favored seedling sprouting.Key words: Saccharum officinarum, protected environment, shade net, propagation of seedlings Brotação de mudas pré-brotadas de cana-de-açúcar e variáveis micrometeriológicas sob malhas fotosseletivas RESUMO: A cana-de-açúcar é uma gramínea que se destaca mundialmente na produção de etanol. O Brasil é o maior produtor mundial e líder na exportação, responsável por mais de 50% dos produtos derivados que são comercializados no mundo. Objetivou-se averiguar a influência de malhas fotosseletivas nas variáveis micrometeorológicas e na brotação de mudas pré-brotadas de cana-de-açúcar. A pesquisa foi realizada em ambiente protegido na Universidade Federal Rural de Pernambuco, em delineamento inteiramente casualizado. As mudas da cultivar RB92579 foram obtidas pela técnica de produção de mudas pré-brotadas. O ambiente protegido foi dividido em quatro módulos, correspondentes aos tratamentos: coberto com plástico polietileno de baixa densidade anti-UV + malha ultranet vermelha Solpack ® , + malha branca Solpack ® , + malha freshnet Solpack ® e sem malha de sombreamento. Foram registrados os dados micrometeorológicos de temperatura do ar e temperatura do substrato em cada módulo. Foram calculadas a primeira contagem de emergência, o índice de velocidade de brotação e a porcentagem de brotação. Foi utilizada a análise multivariada de componentes principais para verificar a associação entre os módulos de cultivo e as variáveis micrometeorológicas e de brotação das mudas. A temperatura do ar no ambiente protegido foi 8.7% maior ...

Ferronickel mining slag on substrates for production of pre-sprouted sugarcane seedlings

“…This technique avoids the use of tolets in planting, and these can be directed to the production of sugar and alcohol (Aquino et al, 2018) The use of presprouted seedlings (MPB) in sugarcane plantations is a management practice that has been increasingly used in the sugar-energy agroindustry, consisting of a multiplication system through the germination of the yolks in the nursery system with the use of substrates. This system has contributed to the rapid production of seedlings, associating a high standard of plant health, vigor and uniformity (Cordeiro Júnior et al, 2019;L. S. Santos et al, 2020).…”

“…This system increases uniformity in planting lines, reduces the number of failures, reduces the volume of seedlings, reduces the risk of spreading pests and diseases and accelerates the introduction of varietal technologies in agricultural areas, allowing us to achieve increased efficiency and economic gain in the implementation of nurseries, replanting commercial areas and expansion and renewal of planted areas of sugarcane (Cordeiro Júnior et al, 2019;Landell, 2012). This system is dependent on the availability and quality of the substrate, which should bring together a number of ideal physical-chemical properties (Braga, 2016).…”