Integration of Root-knot Nematode Resistant Pepper Cultivars into an Organic and Sustainable Production System in Florida

Project Overview

GS22-254
Project Type: Graduate Student
Funds awarded in 2022: $16,232.00
Projected End Date: 08/31/2025
Grant Recipient: University of Florida
Region: Southern
State: Florida
Graduate Student:
Major Professor:
Dr. Bala Rathinasabapathi
University of Florida

Commodities

  • Vegetables: cucurbits, peppers

Practices

  • Pest Management: cultural control
  • Production Systems: organic agriculture

    Abstract:

    Consumer preference is growing in organic field production of vegetables, including peppers. However, a major challenge for organic production is managing diseases, including root-knot caused by the southern root-knot nematode (RKN; Meloidogyne incognita). Since chemical nematicides are severely limited in organic production, two primary methods for production involves deploying resistant cultivars and amending the soil. RKN resistant pepper cultivars are available for commercial production, but currently there is a scarce genetic diversity regarding resistance conferred against this pathogen. The objective of this work is to test RKN resistant pepper cultivars with value for improving productivity of organic operations. We propose to test the impacts of integrating an advanced inbred line of pepper (‘UFRJ107(6)A3’, named ‘Ruby’) into production in a pesticide-free system, in which compost application is used as a tool to both suppress RKNs and improve soil fertility. Gaining insight into the range of pepper host resistance as a supplement to cultural management practices involving organic amendments will be valuable for providing research-based recommendations to vegetable growers in the Southern United States.

    Although soil treatments (chemical fertilizer vs. chicken manure) affected total fruit yield, all reproduction parameters and soil RKN densities were only significantly different between pepper cultivars. ‘Ruby’ displayed high levels of resistance when grown under pesticide-free conditions; however, a few ‘Ruby’ plants in the chicken manure–amended plot enabled high RKN reproduction.

    Project objectives:

    1) Evaluate productivity of pepper cultivars differing in RKN resistance when integrated with soil organic amendment treatments in RKN-infested plots to measure effectiveness of genetic resistance under field conditions.

    Field trials will be conducted at the University of Florida Plant Science and Research Education Unit (PSREU) located in Citra, Florida. They will be maintained in areas reserved for organic production research. Soil samples will be collected at the beginning and end of field trials to determine rate of change in RKN population density. The efficacy of organic amendments, with or without RKN resistant pepper varieties, for the management of RKN will be tested and measured through plant productivity and susceptibility to RKN. Pepper plant productivity will be measured by analysis of total fruit yield at time of harvest, fruit quality parameters, and plant nutrition during early vegetative and 50% flowering stages. Pepper plant roots will be evaluated for levels of RKN galling and rate of reproduction at the time of harvest to measure effectiveness of resistance. 

    2) Verify the identity of the species of RKNs isolated from roots of infected plants

    3) Report the results of this research to inform BMPs and plant breeders involved in production systems dealing with RKN.

    The work is intended to address issues of pepper cultivar selection with relevance to economic loss due to RKN infection. Also, it will address the effect of organic amendment on both pepper plant productivity and level of RKN disease in susceptible pepper cultivars. This objective includes dissemination of information through extension outreach, conference presentations and research publications in refereed journals.    

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and should not be construed to represent any official USDA or U.S. Government determination or policy.