Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes

Thesis (MScAgric)--Stellenbosch University, 2022.

Saved in:
Bibliographic Details
Main Author: Potgieter, Johan
Other Authors: Le Roux, Marcellous
Format: Thesis
Language:en_ZA
Published: Stellenbosch : Stellenbosch University 2022
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613856184926208
access_status_str Open Access
author Potgieter, Johan
author2 Le Roux, Marcellous
author_browse Le Roux, Marcellous
Potgieter, Johan
author_facet Le Roux, Marcellous
Potgieter, Johan
author_sort Potgieter, Johan
collection Thesis
dc_rights_str_mv Stellenbosch University
description Thesis (MScAgric)--Stellenbosch University, 2022.
format Thesis
id oai:scholar.sun.ac.za:10019.1/124796
institution Stellenbosch University (South Africa)
language en_ZA
last_indexed 2026-06-10T12:42:46.825Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository
publishDate 2022
publishDateRange 2022
publishDateSort 2022
publisher Stellenbosch : Stellenbosch University
publisherStr Stellenbosch : Stellenbosch University
record_format dspace
source_str SUNScholar — Stellenbosch University Repository
spelling oai:scholar.sun.ac.za:10019.1/124796 Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes Potgieter, Johan Le Roux, Marcellous Stellenbosch University. Faculty of AgriSciences. Dept. of Agronomy. Tomato growers Controlled release fertilizers Greenhouse tomato production Controlled environment agriculture Tomatoes -- Fertilizers Tomatoes --Growth -- Yields Greenhouse management UCTD Thesis (MScAgric)--Stellenbosch University, 2022. ENGLISH ABSTRACT: To be able to grow crops such as tomatoes on a commercial scale under stringent controlled conditions in what is termed controlled environment agriculture (CEA), requires a great amount of expertise and technology. Therefore, the aim of this study was to see if the use of controlled release fertilizer as an alternative low expertise and low technology-based fertilization method could produce the same yields and marketability than the conventional fertigation fertilization methods used in greenhouse tomato production. The study assessed this by (1) determining if the ratio of perlite to coco coir in the growth medium had any effect on the yield response to an industry recommended controlled release fertilization recommendation, (2) trying to establish an appropriate mixing ratio of controlled release fertilizer (CRF) and liquid fertilizer (LF) to determine if a follow up fertilization application of the pre-plant applied CRF can obtain improved yields. From the results it was evident that by applying a mixture of 80% CRF (based on the fraction of the total % nitrogen applied) and 20% LF with additional monthly manual application of calcium sulphate or calcium nitrate to each planting bag, CRF could potentially replace a 100% LF fertilization programme in greenhouse tomato production. Some results here indicate that a spike in temperature at the beginning of the growing season may have contributed to the premature release of nutrients from the CRF prill, causing a spike in EC. This stunted the growth of the plants for the rest of the season, which could have been attributed to an initial toxic level of salts in the rootzone and a prolonged deficit of other essential nutrients. The growth media trial for the determination of the optimal perlite: coco coir ratio revealed that a mix consisting of 20% perlite to 80% coco coir, or 40% perlite and 60% coco coir were the best ratios that yielded the highest. Thus, for tomato production the effect of CRF would be greatly improved if applied in an environment where the temperature and growth media properties are favourable for the slow release of the nutrients. The evidence here did not support the utilisation of 100% CRF as a replacement of the currently employed LF for commercial greenhouse tomato production. In addition, it is imperative that additional calcium (Ca2+), Sulphate (SO42-) and Nitrate (NO3-) be supplemented to reap the full benefits of CRF due to the ongoing technological research into the ability to coat calcium-based fertilizer products as a CRF. AFRIKAANSE OPSOMMING: Geen opsomming beskikbaar. Masters 2022-02-18T12:58:53Z 2022-04-29T09:33:36Z 2022-02-18T12:58:53Z 2022-04-29T09:33:36Z 2022-04 Thesis http://hdl.handle.net/10019.1/124796 en_ZA Stellenbosch University 73 pages : illustrations, graphs application/pdf Stellenbosch : Stellenbosch University
spellingShingle Tomato growers
Controlled release fertilizers
Greenhouse tomato production
Controlled environment agriculture
Tomatoes -- Fertilizers
Tomatoes --Growth -- Yields
Greenhouse management
UCTD
Potgieter, Johan
Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes
title Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes
title_full Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes
title_fullStr Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes
title_full_unstemmed Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes
title_short Controlled release fertiliser as a management tool for productivity of tunnel-grown tomatoes
title_sort controlled release fertiliser as a management tool for productivity of tunnel grown tomatoes
topic Tomato growers
Controlled release fertilizers
Greenhouse tomato production
Controlled environment agriculture
Tomatoes -- Fertilizers
Tomatoes --Growth -- Yields
Greenhouse management
UCTD
url http://hdl.handle.net/10019.1/124796
work_keys_str_mv AT potgieterjohan controlledreleasefertiliserasamanagementtoolforproductivityoftunnelgrowntomatoes