Standardization of Switchgrass Sample Collection for Cell Wall and Biomass Trait Analysis

Abstract

As a native, low-input crop with high biomass production, switchgrass (Panicum virgatum) has become a favorable feedstock for the production of cellulosic biofuels in the United States. Many efforts are being made to improve the production of cellulosic biofuels from switchgrass. Protocols regarding analysis of switchgrass biomass have been established; however, the developmental stage of the materials being analyzed has varied depending on researchers' discretion, and no standardized harvesting procedure has been defined. Developmental stages have a large impact on the results of biochemical analyses. We propose a standardized procedure for switchgrass sample collection for cell wall and biomass analyses by describing various developmental stages of switchgrass, defining the R1 stage as the stage at which tillers should be collected, and providing a detailed description of how and what material should be analyzed. Such a standardized procedure will help to maintain consistency in switchgrass evaluation methods, enable comparisons of data obtained from different approaches and studies, and facilitate efforts towards improving switchgrass as a bioenergy crop.

Downregulation of a UDP-Arabinomutase Gene in Switchgrass (Panicum virgatum L.) Results in Increased Cell Wall Lignin While Reducing Arabinose-Glycans

“…The non-transgenic (ST1) control was derived from callus that was treated identically as the transgenics with the exception of not being exposed to A. tumefaciens nor hygromycin each replicate, starting from a single-tiller, was grown in its own a 4 L pot that was randomly sited in the greenhouse. Plants were grown until the reproductive (R1) developmental stage as defined by Hardin et al (2013) and tiller and panicle numbers were counted. The five tallest tillers for each replicate were used to estimate total plant height.…”

Transgenic switchgrass (Panicum virgatum L.) biomass is increased by overexpression of switchgrass sucrose synthase (PvSUS1)

“…RNA was extracted from leaves from PvSUS1 overexpressors and control plants at E4 developmental stage [21,27] using TRIREAGENT (Molecular Research Center Inc.) according to manufacturer's instructions. Following extraction, 5 μg of total RNA was treated with 1 unit of DNase I (Promega Corporation) in a 10 μL reaction volume.…”

A Genomics Approach to Deciphering Lignin Biosynthesis in Switchgrass

“…Lignification of the cell wall is tightly regulated in different tissues during different developmental stages, even within different horizontal sections of a single internode of a tiller (Shen et al, 2009b). We have made use of this phenomenon by selecting the top, middle, and bottom sections of internode four (I4) at elongation stage four (E4) (Moore et al, 1991;Hardin et al, 2013) for transcriptomic analysis of candidate monolignol pathway genes. To provide additional predictive power, we have developed a switchgrass cell suspension system in which lignification can be induced.…”