Brassicas: Application of chlorophyll fluorescence for prediction of harvest maturity in broccoli


Project summary:

Identifying the optimum harvest maturity for broccoli is difficult. As a consequence variability in the storage behaviour and shelf-life of the product is often observed within consignments. This project aims to identify methods to monitor maturity and changes in plant health using the technique of chlorophyll fluorescence (CF), thereby affording the opportunity to develop a hand held sensor for use in the field to optimise harvest time. This will be linked to assessments for storage and shelf-life behaviour and the presence of health promoting antioxidants and isothiocyanates. Working closely with Hansatech Instruments Ltd, the project team will identify appropriate adaptations to existing equipment to optimise measurements. Changes in the CF profile of four major broccoli cultivars; Ironman, Parthenon, Marathon and Steel will be followed during maturation in the field, and correlated with morphological and biochemical changes, as well as shelf-life following harvest. This information will be used to identify a strategy to use CF to predict the harvest window for keeping product in store and for optimising practices that maximise the nutritional content of broccoli after harvest.


Benefits to industry:
Reduced wastage and improved productivity
The results of this project will be communicated back to growers through the HDC and dissemination events. This will immediately enable growers to use existing equipment to determine optimal harvest time by field. Subsequent development of sensors through Hansatech Instruments will open the opportunities for more sophisticated selection for harvest in the longer term, possibly to the level of individual heads.
Project code:
FV 425
01 April 2014 - 30 November 2016
AHDB Horticulture
AHDB sector cost:
Project leader:


FV 425_Report_Annual_2016 FV 425_Report_Final_2016 FV 425_Report_Annual_2015 FV 425_GS_Final_2016 FV 425_GS_Annual_2015 FV 425_GS_Annual_2016

About this project

Aims and objectives:

Project aim(s):
To develop a protocol to use chlorophyll fluorescence sensors to aid the prediction of harvest maturity of broccoli
Project objective(s):
1) To optimise an existing chlorophyll fluorimeter for use on broccoli heads in collaboration with the manufacturer (Hansatech Instruments Limited)
2) To relate chlorophyll fluorescence profiles of broccoli to maturation in the field as estimated by the effective day degrees after transplant and morphological characteristics
3) To Identify biochemical changes (antioxidants and isothiocyanates) during broccoli head maturation
4) To determine the optimum harvest window for extending the storage and shelf-life of broccoli
5) To model broccoli head maturity, including biochemical and morphological changes in terms of chlorophyll fluorescence profile.