2017 journal article

Comparative Analysis of Root System Morphology in Tomato Rootstocks

HORTTECHNOLOGY, 27(3), 319–324.

By: D. Suchoff n, C. Gunter n & F. Louws n

co-author countries: United States of America 🇺🇸
author keywords: Lycopersicum esculentum; WinRHIZO; grafted; specific root length; average root diameter; total root length
Source: Web Of Science
Added: August 6, 2018

At its most basic, grafting is the replacement of one root system with another containing more desirable traits. Grafting of tomato ( Solanum lycopersicum ) onto disease-resistant rootstocks is an increasingly popular alternative for managing economically damaging soilborne diseases. Although certain rootstocks have demonstrated ancillary benefits in the form of improved tolerance to edaphic abiotic stress, the mechanisms behind the enhanced stress tolerance are not well understood. Specific traits within root system morphology (RSM), in both field crops and vegetables, can improve growth in conditions under abiotic stress. A greenhouse study was conducted to compare the RSM of 17 commercially available tomato rootstocks and one commercial field cultivar (Florida-47). Plants were grown in containers filled with a mixture of clay-based soil conditioner and pool filter sand (2:1 v/v) and harvested at 2, 3, or 4 weeks after emergence. At harvest, roots were cleaned, scanned, and analyzed with an image analysis system. Data collected included total root length (TRL), average root diameter, specific root length (SRL), and relative diameter class. The main effect of cultivar was significant ( P ≤ 0.05) for all response variables and the main effect of harvest date was only significant ( P ≤ 0.01) for TRL. ‘RST-106’ rootstock had the longest TRL, whereas ‘Beaufort’ had the shortest. ‘BHN-1088’ had the thickest average root diameter, which was 32% thicker than the thinnest, observed in ‘Beaufort’. SRL in ‘Beaufort’ was 60% larger than ‘BHN-1088’. This study demonstrated that gross differences exist in RSM of tomato rootstocks and that, when grown in a solid porous medium, these differences can be determined using an image analysis system.