Hoda, M. Mohamed; Faten, A. Al- kamar; and Azza, A. M. Abd-Elall( 2013). Effect of Magnetite and Some Biofertilizer Application on Growth and Yield of Valencia Orange Trees Under El – Bustan Condition Nature and Science 2013;11(6)
Abstract: The response of Valencia orange trees (Citrus Sinensis) budded on Volkamer lemon rootstock (Citrus Volkameriana) to Magnetite, Diatoms and biofertilizer (mixture of Cyanobacteria and Azolla) were studied during (2011 & 2012) seasons. Trees were four years old, planted at 4x6m apart (175 trees/ feddan), under drip irrigation system and growing in soil influenced by salinity, (where EC was 3.64 ds/m), in a private orchard, located at El
Bustan County, El Behera Governorate, Egypt. The experiment involved 14 treatments. The obtained results indicated that, the application of biofertilizer plus 750 gm. Magnetite treatment was the best combination for achieving the highest total yield (51.44, 38.22 % over control) during two seasons, respectively. Diatoms either singly or in combination with Magnetite treatments improved fruit peel quality, where, (the peel thickness and
firmness has increased, fruit peel was more lightness and had high good color quality), so it seems more attractive. Diatom treatments could earlier the harvest date by increasing fruit TSS/ Acid ratio and Vitamin C contents and to decrease fruit acidity especially Diatoms at5 ppm plus 750 gm. Magnetite. All treatments slightly reduced soil EC and pH, increased leaf K+ and reduced Na+ uptake especially biofertilizer plus 750 gm. Magnetite treatment.
Treatments also enhanced of the soil biological activity in terms of increasing the total (bacterial, cyanobacterial) counts and CO2 evolution. Based on the economic study, it could be recommended to use biofertilizer plus 750 gm. Magnetite for achieving the best total yield and produced the highest net profit / fed., (4541.75 L.E), or use Diatoms
at 5 ppm plus 750 gm. Magnetite for giving the high fruit peel quality which very important characteristics especially when fruits tended to be exported and earlier maturation of fruit as well as increased net profit / fed. (3426.75 L.E).While, it could not be recommended to use biofertilizer alone because it caused loss of money (-742 L.E). [Hoda, M. Mohamed; Faten, A. Al- kamar; and Azza, A. M. Abd-Elall. Effect of Magnetite and Some Bio fertilizer Application on Growth and Yield of Valencia Orange Trees Under El – Bustan Condition. Nat Sci
Keywords: (Magnetite, Diatoms, cyanobacteria, Azolla, yield, fruit quality and, Valencia orange trees.)
