Cover Crops for Improving Recalcitrant Soil Organic Matter and Soil Biota Management in Plantain Production Systems in Puerto Rico

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2013: $10,000.00
Projected End Date: 12/31/2016
Region: Southern
State: Puerto Rico
Principal Investigator:
Duamed Colon-Carrion
Agro Tropical, Inc.

Annual Reports


  • Agronomic: sorghum (milo), sugarcane
  • Vegetables: peppers, cucurbits
  • Animals: bees


  • Crop Production: conservation tillage
  • Education and Training: farmer to farmer, on-farm/ranch research, participatory research
  • Energy: energy conservation/efficiency
  • Farm Business Management: farm-to-institution
  • Natural Resources/Environment: carbon sequestration, biodiversity, habitat enhancement
  • Soil Management: green manures, organic matter, soil analysis, soil microbiology, soil quality/health
  • Sustainable Communities: leadership development

    Proposal summary:

    The goal of this project is to improve the soil quality by increasing RSOM and SB through the adaptation and implementation of cover crops (CC) to plantain (Musa paradisiaca AAB) production systems in PR (currently PR's most important crop).  We will quantify and characterize RSOM and SB as a function of the use of CC. This project will provide an actual scenario for conducting sustainable tropical soil quality participatory-research by producers, researchers and university students in PR.

    By using CC we are inducing changes in the soil carbon cycle that increase the carbon inputs to soil through the RSOM formation.  Tropical CC such as Crotalaria juncea (Sunnhemp), Jack bean, and Sorghum have been reported as being excellent sources of organic matter in the tropics.  

    The non-labile organic (fibrous) fractions (high in lignin) of these CC are converted to RSOM by soil microorganisms, typically by lignocellulolytic fungi (López et al., 2006).  CC species mixes are reported to be more productive than the use of CC as monoculture.

    This project will be managed and located in a 5-acres farm at the University of Puerto Rico Agricultural Experiment Station  (Municipality of Gurabo, PR), using in-vitro AMF/RPNBF-inoculated plantain plantlets produced at the UPR-Mayagüez.   Standard plantain crop growth and health assessments will be performed during the 2 growing seasons.

    Project objectives from proposal:

    This project objective is to determine as a function of CC use on plantain crop systems: 1) soil RSOM formation rates; 2) soil microbial biomass (SMB); 3) Dehydronase activity.  

    Six CC treatments will be evaluated [{1}Jack Bean (JB) (Canavalia ensiformis), {2}Sunnhemp (Crotalaria juncea), {3}sorghum (Sorghum bicolor), {4}JB+Sunnhemp, {5}JB+sorghum, {6}JB+Sunnhemp+sorghum]. CC will be seeded in 2-feet apart rows (intra-row distance: JB and sorghum 6-inches; Sunnhemp 3-inches). No CC will constitute the control. JB will be let stand for the whole plantain crop cycle (~12 months). The Sunnhemp will be let stand for seed harvest (4months), then mowed and used as mulch. The sorghum will be mowed (4-inches above ground) at 3-months, allowing it for a second growth cycle. After plantain harvest a CC-mix (JB+Sunnhemp+sorghum) will be planted as crop rotation for 3 months, then the CC-mix will be soil incorporated.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.