Seedling emergence of five varieties of citric rootstocks grown in environments with different levels of shading

Abstract

The emergence of citrus seedlings is influenced by several factors. One is the degree of brightness. The objective of the experiment was to evaluate the influence of four environments in the emergence of seedlings of five citrus varieties rootstocks. The work was carried out on private property located in the city of Alegre-ES, located at 20° 49’ south latitude and 41° 32’ west longitude and 322 m altitude. The experimental design was completely randomized in a split plot, with four rooms consisting of 0, 30, 50 and 80% shading in the plot and five varieties of rootstocks subplots, with four repetitions and twenty-five seeds per replicate. The rootstocks used were the Rangpur lime, lemon Volkameriano, Poncirus trifoliata, ‘Swingle’ citrumelo and Flying Dragon. After 60 days of sowing, emergence rate index, emergence percentage, leaf number and height were evaluated. At 124 days, leaf area, total chlorophyll (a + b), root dry mass and shoot were evaluated. The citric rootstocks tested responded differently when subjected to shading, and can use physiological and morphological mechanisms to maintain or even improve the emergence and seedling vigor. It was observed that the P. trifoliata rootstock obtained better performance when compared to others and that 50% shading can be adopted in this stage of citrus seedling production since it reduces seedling time in the tubes and does not affect the seedling quality.