Effect of drought length on the performance of cabbage (Brassica oleracea var capitata) in the forest-savannah transition zone, Ghana

R Kotei,E Ackah

doi:10.1007/s40502-020-00541-5

Abstract

The drought tolerance of Cabbage, Brassica oleracea var capitata (Oxylus) was investigated by subjecting the initial, development and mid growth stages to varying drought lengths of 5, 7, 9, 11, 13 and 15 days in a 7 × 3 factorial experiment to determine the effect of each drought period at each growth stage on growth and yield. Data on number of opened leaves/plant, leaf area index (LAI), leaf chlorophyll content, head size and yield/ha were recorded due to drought effect at each growth stage. Analysis of variance at 5% probability level indicated that drought periods of 5–15 days at the initial stage significantly reduced number of leaves, LAI and head size. Significant reduction in chlorophyll content and yield were due to drought beyond 11 and 5 days respectively at the initial stage. Number of opened leaves increased significantly with increasing drought length at the development stage; critical at 11 days drought. Significant reductions in LAI at the development and mid stages were critical at 11 and 9 days respectively whilst chlorophyll content was significantly reduced at both the development and mid stages by all drought periods. Significant reduction in head size at the development and mid stages was critical at 7 days. Generally, the drought tolerance of cabbage increased from the initial to the mid-stage. To maintain economic yields of cabbage in the forest-savannah transition zone, the initial and development stages could tolerate drought stress up to 5 days whilst the mid stage could tolerate up to 7 days.

Highlights

Cabbage (Brassica oleracea L. var. capitata) is a vegetable crop grown worldwide including African countries (Grzywacz et al 2010)
Number of opened leaves decreased at the initial stage, increased at the development stage but remained constant during the mid-stage
The control plants produced the highest number of leaves (13), preceded by 5 days drought stressed plants (11 leaves) whilst the rest of the drought periods, similar in their effects on number of leaves at the initial stage, each resulted in 23.1% reduction in number of leaves

Summary

Introduction

Cabbage (Brassica oleracea L. var. capitata) is a vegetable crop grown worldwide including African countries (Grzywacz et al 2010). Capitata) is a vegetable crop grown worldwide including African countries (Grzywacz et al 2010). In Ghana, cabbage production is mostly popular among peri-urban and urban dwellers in response to high demand (Timbilla and Nyarko 2004). Cabbage is grown in cities and rural communities in Ghana and it serves as an important source of livelihood for many smallholder farmers in Ghana (Baiphethi and Jacobs 2009). The world’s annual production of cabbage is around 70,644,191 tons with an average yield of about 29.23 ton/ ha (Kidane 2016). The major production constraints mostly reported in Ghana are insect pests, diseases, the need for high fertilizer input and the high cost of pesticides (Williamson et al 2008)

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Results

Discussion

Conclusion