Variety specific responses of cauliflower varieties (Brassica oleracea var. botrytis) to different N application rates on yield, colour and ascorbic acid content at harvest

• Published in: Acta Agriculturae Scandinavica, Section B — Soil & Plant Science
• Main Authors: Madonna N. Mashabela, Martin M. Maboko, Puffy Soundy, Dharini Sivakumar
• Format: Article in Journal/Newspaper
• Language: English
• Published: Taylor & Francis Group 2018
• Subjects: vegetable crop; bioactive compounds; chromaticity coordinates; fertiliser application; fresh mass; Plant culture; SB1-1110; eskimo*
• Online Access: https://doi.org/10.1080/09064710.2018.1440002; https://doaj.org/article/4c31ca2d41094545b8870834e55be01a

The influence of five nitrogen (N) application rates (60, 90, 120, 150 and 180 kg N/ha) were evaluated using limestone ammonium nitrate on the curd fresh and dry mass, size, chromaticity coordinates, L*, a*, b* and ascorbic acid content in cauliflower varieties (Largardo, Eskimo and CF-744) during the 2015 and 2016 seasons. Commercial standard 120 kg N/ha was included as a control. Variety ‘Largardo’ showed weak response to N application rates and can be regarded as the least sensitive variety for lower N use. Curd fresh and dry mass and size were not affected at lower N application rates of 60 and 90 kg/ha in ‘Largardo’ compared to the other two varieties. However, L*, b* colour value and ascorbic acid content was higher at lower N application rates <90 kg N/ha in all three varieties. With increasing N application rates, curd became darker and less intense in yellow colour. Increasing rates of N application clearly posed a negative effect on ascorbic acid content. Therefore, ‘Largardo’ can be recommended as a suitable variety that produces higher yield and ascorbic acid content at 60 or 90 kg N/ha, with the application rates lower than the commercially recommended rate (120 kg N/ha).