Relationship Between Distribution of the Radicular System, Soil Moisture and Yield of Sugarcane Genotypes

Abstract

The objective of the study was to associate soil moisture, aerial biometric characteristics, and root distribution patterns in the yield of sugarcane genotypes in the fourth ratoon and the relationships between these characteristics. We used five sugarcane genotypes (CTC9002, RB044311, RB044313, RB044336, and RB867515) and five soil depths (0–20, 20–40, 40–60, 60–80 and 80–100 cm deep). The evaluations were carried out in December 2019. We evaluated the root systems, the soil water content at the five depths, the aerial biometric characteristics, and the productive yield. In the roots, the genotypes RB044311, RB044313, RB044336, and RB867515 showed a higher yield. On average, genotypes showed 50% of dry weight and total root length at a depth of 0–20 cm, 73% between 0 and 40 cm, and 86% between 0 and 60 cm. The RB044336 genotype showed maximum height and number of buds. The RB867515 genotype had the largest average stem diameter and CTC9002, the largest number of tillers. The genotypes CTC9002 and RB867515 presented the highest soluble solids' content, apparent sucrose in the juice, and total reducing sugars. These genotypes showed a 26% and 57% higher root density in soil layers at depths of 60–80 cm, respectively, 79% and 86% in the 80–100 cm layer, about the layer with the highest concentration of 0–20 cm roots. These layers remained with the highest soil moisture levels during the period of establishment and intensive cultivation growth. Thus, there was a relationship between root distribution dynamics and soil moisture in different areas.