5068
SAMI HOSNI MAHMOUD IBRAHIM
EFFECT OF PHOSPHORUS, SULPHUR AND SOME BIOSTIMULANTS ON PRODUCTIVITY OF POTATO
Potato, phosphorus, seaweed, chitosan, potassium silicate, and yield.
Two field experiments were carried out during the two successive growth seasons of 2012/2013 and 2013/2014 in a sandy soil at Sadat City, Taba Farm, EL-Menofyia Governorate to study the effect of phosphorus sources, seaweed rates, sulphur rates and some bio-stimulants (amino acids, chitosan and potassium silicate) on potato productivity. First experiment: This experiment included 9 treatments which were the simple combinations between three phosphorous fertilizer sources ,i.e. single super phosphate "SSP", Mono-Ammonium Phosphate (MAP) and Di-Ammonium Phosphate (DAP), with foliar application of three levels of seaweed extract (0, 2.5 and 5 cm3/L). Second experiment: this experiment included 12 treatments which were the simple interactions between three levels of agricultural sulphur (0, 150 and 300 kg/fed) and spraying with three bio-stimulant substances, i.e. amino acids (2.5 cm3/L), chitosan (5 cm3/L) and potassium silicate (2 cm3/L), in addition to tap water as a control treatment. The obtained results indicated that to increase the total tuber yield and its components, it is favorable to supply potato plants with phosphorus in the form of DAP or MAP, where they caused significant vigorous plant growth (plant height, number of leaves/ plant, number of shoots/plant, fresh and dry weight of leaves and shoots, leaf area, leaf area index, relative growth rate and net assimilation rate). The highest values of total photosynthetic pigments and its fractions were determined in plants supplied with phosphorus fertilizer in DAP form. Using either MAP or DAP caused an increase in total tuber yield and its components, if compared with using the traditional super-phosphate. Potato plants which received DAP as phosphorus fertilizer source gained the best nutritional values if compared with the other phosphorus sources.Seaweed extracts had a favorable effect on plant growth parameters andtotal tuber yield as foliar spraying at rate of 2.5 or 5.0 cm3/L. The foliar spraying of seaweed caused an enhancement in all physical properties and nutritional value of potato tubers if compared with that plants sprayed with tap-water (control). The addition of sulphur resulted in a superiority in most the vegetative growth measurements, moreover increasing level of sulphur caused a gradual increase in the estimated parameters. Particular within 150 up 300 kg/fed., gained the highest total and marketable yield and the lowest un-marketable yield. The best physical and chemical constituents of tubers were recorded with potato plants received sulphur at a rate of 150 or 300 Kg/fed. Also, the obtained data reveal that there were no significant differences between amino acid and chitosan. The foliar spraying by amino acid mixture gave the highest values of fresh and dry weight of whole plant, The heaviest total and marketable tuber yield and the lowest value of un-marketable yield. The values of starch, total carbohydrates, total sugar, dry matter, N, P, K, Ca, Fe, Mn, Zn and Cu, were increased with spraying by the bio-simulative substances if compared with plants treated by tap-water.
2016
Ph.d
Ain Shams
Agriculture