Tifton roots replace sphagnum moss as substrate for air-layering litchi tree

This research aimed at evaluating alternative substrates for air-layering litchi trees of cultivar ‘Bengal’. The experimental design was in randomized blocks and the treatments were arranged in a factorial scheme 4×2 with four substrates (seaweed, roots of Tifton 85, coconut fiber and sphagnum moss) and two substrate volumes (50 and 100 cm³), with four replications; the experimental unit consisted of five air-layers. 120 days later, the percentages of callusing and rooting, the length of the longest root, root volume and root dry matter weight were evaluated. The substrates containing sphagnum moss (50 and 100 cm³) and Tifton 85 root led to higher values for all the evaluated characteristics when the volume of 100 cm³ was used. The air-layers from the coconut fiber substrate had results that were inferior to those obtained with the Tifton 85 roots and sphagnum, but they were superior to the results observed with seaweed as substrate. Coconut fiber and algae presented a low rate of rooting despite the high rate of callus formation. The layerings on the seaweed-based substrate also showed excess of water, as well as sand and sea salt residues, besides dead branches. The sphagnum and Tifton 85 roots presented the best results for biometric root variables. Thus, it is possible inferring that Tifton 85 roots show features as satisfactory as those of the sphagnum, as well as that they enable good layering development. The conclusion driven from the results is that Coconut fiber leads to low rooting rate in the layering of ‘Bengal’ lychees. The methodology adopted for the washing of seaweeds made it impossible to use it as a substrate in lichieiras 'Bengal'. The sphagnum moss can be replaced by the Tifton 85 roots, at 100 cm³, as substrate without impairing the root development of air-layers of ‘Bengal’ litchi tree.