Crescimento de mudas de cafeeiro inoculadas com fungos micorrízicos arbusculares

Abstract

The objective of this work is to analyze the growth of coffee seedlings inoculated with mycorrhizal fungi, through the analysis of plant growth. The experimental design was completely randomized in a 2x6 factorial design, with control and inoculated seedlings six evaluation periods, with six replications. Catuaí Vermelho IAC 99 seeds were desinfested and germinated in autoclaved sand. After 75 days, at the time of transplanting, half of the seedlings were inoculated by applying spores of species Glomus clarum and Gigaspora margarita. At the time of inoculation (0) and at 30, 60, 90, 120 and 150 days plant height and leaf area were measured, and subsequent determination of total and leaf dry mass. The data were extrapolated to determine the measures of non-linear growth analysis. In general, the inoculated plants showed a negative effect on early growth, but at the end of the experiment had superior growth than uninoculated seedlings. Growth analysis enabled a better understanding of the association, and found that despite the increased investment in morphology for energy harvesting, there was no increase in net assimilation rate and may consider that initially fungi represented drain assimilated, but in the end the seedlings inoculated grew up. The association may be considered to be a sink while the plants do not have leaf area enough to maintain the association, leading to reduction in the liquid photosynthetic rate. This sink ends later, and there is a net benefit for the seedlings, at the end of the production period.