Chemical Composition of Residue from Cereal Crops and Cultivars in Dryland Ecosystems

Abstract

Cropping systems in the dryland farming region of eastern Washington State are dominated by winter and spring wheat (Triticum aestivum L.) and spring barley (Hordeum vulgare L.). Excessive levels of residue may be an obstacle in the adoption of conservation farming systems. Decomposition of cereal crop residues is associated with fi ber and nutrient content, and growers have observed diff erences in decomposition among cultivars; however, little information exists on their residue characteristics. Cultivars of spring barley (SB), spring wheat (SW), and winter wheat (WW) grown at four locations over two crop years were analyzed for neutral detergent fi ber (NDF), acid detergent fi ber (ADF), acid detergent lignin (ADL), C, and N contents, and winter wheat decomposition was tested in a laboratory incubation study. Acid detergent lignin was highest in spring barley (9.9%), and least in winter wheat (9.2%) and hard white spring wheat (9.5%). Fiber components and nutrient content varied by location, precipitation zone, and cultivar. Residue in the drier year of the study had lower NDF, ADF, ADL, C, and C/N ratio. Foot rot (Fusarium spp.)-resistant winter wheat cultivars had higher NDF, ADF, and ADL than susceptible cultivars. Laboratory incubation studies showed decomposition of winter wheat straw in soil was correlated with ADF (R 2 > 0.66, P = 0.002) and total N (R 2 > 0.67, P = 0.04). Fiber and nutrient characteristics of residue from wheat and barley cultivars currently produced in the Pacifi c Northwest can be used to predict residue decomposition in cropping systems that conserve soil and water, and enhance build-up of organic matter.

Repeat‐pulse 13CO2 labeling of canola and field pea: implications for soil organic matter studies

“…35 Recently, interest in these biochemical plant fractions in the context of assessing crop suitability for bioproducts and biofuels has been building 36 and soil scientists are utilizing biochemical fractions to predict the decomposition of crop residues and the potential impact on soilx. 37 Using these fractions, we found that field pea was generally more readily degradable because of its lower % ADF and % ADL than canola, indicating that field pea would be higher in hemicellulose which is more easily degraded. 37 However, conclusions about degradability that are based on biochemical fractions cannot be assessed without considering the relative quantity of residues that each plant produces.…”

“…37 Using these fractions, we found that field pea was generally more readily degradable because of its lower % ADF and % ADL than canola, indicating that field pea would be higher in hemicellulose which is more easily degraded. 37 However, conclusions about degradability that are based on biochemical fractions cannot be assessed without considering the relative quantity of residues that each plant produces. The balance between crop residue quantity and quality will ultimately dictate changes in soil processes and soil properties.…”

Assessing the Relative Effects of Geographic Location and Soil Type on Microbial Communities Associated with Straw Decomposition

“…Decomposition of plant residues is largely mediated by microorganisms such as bacteria and fungi in the soil (3); the resultant nutritional carbon substrates can either support the growth of crops or be partially stored in the form of soil humus. Given the importance of decomposition in soil carbon sequestration, there has been continued interest in elucidating the dynamic changes of microbial communities during the course of residue decomposition (4)(5)(6)(7).…”

Seasonal Variation of Carbon and Nitrogen Emissions from Turfgrass

“…Neutral detergent fiber (NDF) comprises the insoluble components of cell walls (cellulose, hemicellulose, and lignin). Acid detergent fiber (ADF) is a measure of cellulose and lignin [19].…”