Hydroponic Root Growth: Liquid Fertilizer’s Effect on Paprika From Concentrations in Hydroponic Cultures

Read the full study here.

Research Authors: Jinen Hojo, Hiroyuki Chiba, and Takashi Ikeda, Meiji University, Tokyo, Japan

Aspiring to shed light on the mysteries of plant growth, a team of researchers from Meiji University in Tokyo, Japan, undertook an interesting study to explore the effects of different liquid fertilizer concentrations on the growth of paprika roots in hydroponic cultures. Utilizing the powerful capabilities of CID BIO-science’s Root Imager (CI-600), the team carried out their experiment with careful precision and control.

Hydroponic cultivation, a practice often used for growing paprika, typically involves high-concentration liquid fertilizer. Although one might expect such conditions to hinder plant growth, paprika plants thrive.

The team designed a custom hydroponic system to probe this phenomenon using a transparent acrylic pipe nested inside a surrounding PVC pipe. Thanks to the contrasting black color, a dark agricultural sheet inserted in the PVC pipe encouraged healthy root growth and improved visibility. The team then prepared liquid fertilizer in a container below and systematically pumped it into the plant’s root system.

The study focused on a particular variety of paprika, Capsicum annuum L. “Special,” cultivated in a greenhouse from February to May 2020.

Using the non-destructive and non-contact capabilities of the Root Imager, measurements were taken every ten days post-transplantation, in darkness, for optimal results. Images captured were then analyzed to determine the total root length, surface area, and volume.

To provide a comprehensive understanding, the team designed two experiments. The first measured root growth and dry weight with a liquid fertilizer concentration set at EC 1.5 ds m−1. The second experiment evaluated the impact of different salinity stresses on root growth at two levels of conductivity: EC 1.5 ds m−1, typical for hydroponics, and EC 2.5 ds m−1, used in practical paprika production.

Surprisingly, the results revealed that paprika root growth appeared unaffected by the concentration of liquid fertilizer used. High-concentration liquid fertilizers neither stunted nor boosted root growth. A comparison of total root length, surface area, volume, and dry weight showed a close correlation, indicating the reliability of the non-destructive Root Imager for capturing accurate growth data.

This ground-breaking research found that different liquid fertilizer concentrations may not influence paprika root growth. It also highlighted the effectiveness of the Root Imager in non-destructively measuring root growth. Future research in this field could lead to optimized conditions for hydroponic cultivation, opening new doors for sustainable farming practices.