Cotton root growth is under genetic control but can be decreased by soil factors as Al toxicity and low Ca levels. Lime was applied to a Dark-Red Latosol (sandy loam) with 10% of base saturation, to raise base saturation to 30, 50 and 70%, in order to study the effects of liming on root growth and mineral nutrition of cotton (Gossypium hirsutum L., v. latifolium Hutch), cv. IAC 20, IAC 22 e CNPA-ITA 90 cultivares. The experiment was conducted in pots with 4 L of soil, under greenhouse conditions, up to 37 days after plant emergence in a 3 x 4 factorial design with four replications in randomized blocks. Liming was necessary in order to get a good cotton root growth. The IAC 22 cv. showed roots more tolerant to low soil base saturation than cv. IAC 20 and cv. CNPA-ITA 90. Maximum root growth was observed when the soil base saturation was around 50%. CNPA-ITA 90 showed a higher K absorption and was more tolerant to high Mn levels, showing a decrease in dry matter production at the highest soil base saturation.
Gossypium hirsutum; nutrients; roots; soil saturation
