EFFECT OF SOWING DATE AND FOLIAR SPRAY OF LUPINE SEED EXTRACT ON FOLIAGE YIELD, CHEMICAL COMPOSITION, SEED YIELD AND SEED QUALITY OF SPINACH (Spinacia oleracea L.) AS WELL AS ASSOCIATED WEEDS

Abstract

Two field experiments were performed at the Baramoon Experimental Station, Dakahlia Governorate, Egypt, during the two seasons of 2009/2010 and 2010/2011 to study the effect of two sowing dates (15 Oct. and 15 Nov.) and foliar application with lupine seed extract at various concentrations of 0, 5, 10, 15% as well as their interaction on foliage yield, chemical composition, seed yield and seed quality of spinach plants cv. Dokki as well as associated weeds. A split plot design with three replicates was used. The obtained results revealed that sowing spinach on mid-October resulted in marked increases in plant height, number of leaves per plant, foliage fresh weight per plant, total yield per fedden, dry matter percentage of leaves, nitrate content of leaves, seed production and its quality as well as associated weeds fresh weight, compared with that sown on mid-November in both seasons. Results also cleared that foliar application with the relatively high used concentration of 15 % lupine seed extract had significant promotion for most of the studied characters except associated weeds fresh weight, dry matter percentage of leaves and nitrate content of leaves which were significantly decreased as compared with the control treatment in both seasons. The interaction effect of sowing date and foliar lupine seed extract exhibited significant effect on all studied traits in both seasons. Generally, it could be concluded that sowing spinach cv. Dokki in mid October interacting with application of lupine seed extract at 15% concentration was found to be the best management system for increasing foliage yield, its quality, seed yield and seed quality under the environmental conditions of Dakhlia district. Moreover, applying lupine seed extract could be considered a powerful and environmental friendly approach to improve plant growth, quality and production, and it might open the door for new strategy for controlling the weeds in spinach fields.

Effect of Planting Dates on Vegetative Growth, Yield and Quality of Some Genotypes of Spinach (Spinacia oleraceae L.)

“…These results can be attributed to the increments induced in the number of leaves per plant achieved by the planting date. These results are in agreements with those reported by (Waseem et al, 2000;Ramadan, 2004;Ibrahim et al, 2010;Sensoy et al, 2011 andIbrahim et al, 2012).…”

“…When comparison to the lower temperatures on 1st December and1st January 1 st November's comparatively high temperature promotes vegetative development. this is consistent with Ibrahim et al, (2012) In comparison to earlier sowing dates, December brought about a considerable fall in yield and its component features. Numerous studies showed that compared to later sowing dates, earlier sowing dates yielded higher fresh and overall yields.…”

“…Several investigations confirmed that the early sowing dates led to an increase in vegetative characters compared to the late sowing dates. (Waseem et al, 2000;Ramadan, 2004;Ibrahim et al, 2010;Sensoy et al, 2011 andIbrahim et al, 2012). ) in the first and second seasons, respectively.…”

“…Several investigations confirmed that the earlier sowing dates produced larger fresh comparison with late sowing dates. (Waseem et al, 2000;Ramadan, 2004;Ibrahim et al, 2010;Sensoy et al, 2011 andIbrahim et al, 2012…”

“…(Waseem and Nadeem, 2001;Ramadan, 2004;Ibrahim et al, 2010;Sensoy et al, 2011). Delaying sowing date after October cause a decrease in spinach yield (Ramadan, 2004;Sensoy et al, 2011;Ibrahim et al, 2012,). Plants subjected to long days especially coupled with high temperatures above 25º C induce bolting which reduce the production of spinach crop (Hata et al, 2006).…”