O Sombreamento atenua o efeito estressante por alagamento em mudas de Talisia esculenta (A. ST. - HILL) RADLK?

Abstract

Pitomba is a native Brazilian plant found in almost all Brazilian biomes. Studies on morphophysiological responses of native plants exposed to flooding stress are still scarce. This is known that this is a factor pointed out as the main cause in implementation, recompositing and revitalization of native areas, which will only be guaranteed success when, the factors that alter the survival and initial development of seedlings during the nursery phase and field are known. Given this, it aimed to evaluate the effect of shadow on survival, growth and morphophysiological changes of the seedlings of Talisia Esculenta (A. St. -hill) radlk under flood. The experiment oc curred in nurseries with different levels of shading: 0%, 30%and 70%, and the seedlings of T. esculenta were divided into two groups of different hydric, flooded, simulated through the use of 1000 L pools and control. With daily irrigation, maintaining 75% of water retention capacity in the substrate. The evaluations occurred at 0, 15, 30, 45 and 60 days after the submission of the seedlings to flooding. The evaluated parameters were: initial growth, seedling quality index, survival, morphological structures, photochemical efficiency indices, relative water, proline content and gas exchange. The seedlings of Talisia Esculenta are sensitive to flooding and cultivation under 0% of shading, and these two factors act synergically to accentuate the stressful effect. The shades mitigated the stressful effect of flooding on seedlings, and the 70% shading provided higher quality of seedlings. The fluorescence evaluated in the Fv/Fm, F0/Fm and proline synthesis results contributed to the survival of the seedlings and the resumption of photosynthetic metabolism and growth under stressful conditions of cultivation. Thus, the species under study can be indicated for planting in degraded areas in environments that are subject to flooding, such as riparian forests and regions close to dams.