Effect of Sowing Dates and Number of Cuttings on Yield and Quality of Spinach (Spinacia oleraceae L.)

Abstract

Two field experiments were carried out in clay loam soil at Experimental farm, Baramon, Dakahlia Governorate during the two winter seasons of 2010/11 and 2011/12 to investigate the effect of four sowing dates (15 Oct., 1 Nov., 15 Nov. and 1 Dec.) and three harvesting patterns (without cutting C0, one cutting C1 and two cuttings C2) as well as their interaction on yield and quality of spinach cv. Balady. The experiments were laid out in a split plot design with three replicates where sowing dates were the main factor and the number of cuttings was the secondary factor. The obtained results indicated that sowing date at mid October followed by first of  November promoted vegetative growth characters, which showed a significant increase in plant height, number of leaves/plant and average leaf area. In addition, early sowing at mid October and first of November produced the greatest fresh foliage weight/plant, fresh yield and total fresh yield. Moreover, early sowing dates increased dry matter content in spinach leaves but showed the least values for total chlorophyll content. Harvesting spinach plants without cutting led to an increase in plant height and average leaf area, whereas the second cutting exhibited the largest number of leaves/plant. Harvesting plants without cutting showed the largest means of plant height, average leaf area, foliage fresh foliage weight/plant and fresh yield, while total fresh yield was increased by cutting spinach plants twice. The interaction between sowing dates and number of cuttings showed significant differences for all studied characters in both seasons of the study. Generally, it could be concluded that the suitable treatment to maximize spinach yield was sowing spinach at mid October or first of November and cut plants twice. Otherwise, delaying sowing date causes a reduction in vegetative growth and consequently total yield production