Effect of the use of hydrogel in a substrate formulated with Sphagnum peat and other with subtropical peat to produce seedlings of Impatiens walleriana

Abstract

The incorporation of hydrogel in the substrate was evaluated for seedling
production Impatiens walleriana. The trials were performed in Autumn/Winter and Spring. Treatments : T1) substrate A + 0,5 g L-1, T2) substrate A + 1 g L-1, T3) substrate A + 1,5 g L-1, T4) substrate B without hydrogel, T5) substrate B+ 0,5 g L-1, T6) substrate B + 1 g L-1, T7) substrate B + 1,5 g L-1, T8) substrate A without hydrogel. In every substrate it was analized the percentage with air pores, water holding capacity pores and total pores. Irrigation water in each treatment was recorded and it was measured the root dry mass (MSR), above ground dry mass (MSA) and the relationship MSA/MSR of each seedling. There were no differences in soil pores and water holding capacity pores between treatments of the same substrate. In the first trial, the irrigation water was lower in the T8, without differences between the other treatments and in the second trial it was lower in the T7. In both trials and treatments of the same substrate, there was higher MSA in seedlings of treatments with 1.5 g hydrogel, except the substrate B of the first trial. The incorporation of hydrogel did not significantly reduce the irrigation water needs but favored the increase of seedling MSA.