Growth, yield, and postharvest quality of cabbage (Brassica oleracea L.) in response to different levels of nitrogen fertilizer

Abstract

In the Philippines, vegetable farmers generally apply excessive amounts of fertilizer to maximize yield while not understanding the cost impacts and environmental effects. This study aimed to evaluate the effects of different rates of nitrogen fertilizer on the productivity of two cabbage cultivars. The experiment was conducted as a factorial using a randomized complete block design in two growing seasons. The two factors included level of nitrogen (21, 141, 191, 241, 291, 341 and 391 kg N ha-1) and cultivar ('Resist Crown' and 'KEX-734') with each treatment combination replicated four times. The study showed that application of 291 kg N ha-1 resulted in the highest dry matter, largest heads (polar and equatorial) and highest average yield (35.49 t ha-1) in the two growing seasons. At 391 kg N ha-1, cabbage yielded the highest number of leaves and leaf count increased concomitantly with increasing N application rate. Results further showed that N application at the highest rate (391 kg N ha-1) resulted in the highest postharvest weight loss (33.7%) and shrivelling of cabbage heads. The cultivar 'Resist Crown' produced a greater number of leaves, largest polar head size and consequently highest mean yield (25.7 t ha-1) than cultivar 'KEX-734' in both cropping seasons. The results indicate that an application rate of about 291 kg N ha-1 is recommended for cabbage production since it increases yield through enhancing the size and weight of the cabbage head. 'Resist Crown' was a better cultivar than 'KEX734' having greater yield and postharvest quality. © 2021 International Society for Horticultural Science. All rights reserved.