THE EFFECT OF SUBOPTIMAL IRRIGATION AND INTRA-ROW SPACING ON THE YIELD AND QUALITY OF CABBAGES
Cabbages were planted on a clay-loam soil which was irrigated to field capacity when 30, 60 and 90% of the available soil moisture was depleted during different growth stages. The effect of three intra-row spacings on water use and crop performance under the differential irrigation treatments was determined.
Yield and head mass were enhanced by irrigating at frequent intervals during summer and winter. High soil moisture stress during the vegetative growth period was not detrimental to yield and quality. Regular irrigation from the time of head formation to maturation counteracted previous adverse effects of moisture stress on growth. Stress imposed during the period of head formation to maturity adversely influenced yield and quality. Soil moisture depletion levels were reached sooner during summer plantings.
The three commercially used intra-row spacings did not influence yield but head mass was significantly reduced in the closest planting. Spacing influenced the pattern of water depletion in the soil.
Weekly growth analysis indicated that the development of internal compactness of the heads was enhanced by dry moisture regimes. In the winter trials maturity was attained 10 days earlier in dry regimes than in wet regimes.
Yields of plants increased with the amount of water applied. Closer spacings increased total water requirement. Results indicate that water consumption may be considerably reduced by changing present irrigation practises without adversely influencing quality of cabbage.