A filed experiment was carried out during the two successive seasons of 2016/2017 to study the effect of planting date (20 th September (Sep.) and 10 th October (Oct.), irrigation water level at 50, 75 and 100 % from the filed capacity (FC) and two foliar spray treatments with calcium chloride (1%) and boron ( 60 ppm) singly or in combinations, beside unsprayed treatment as well as their interactions on growth, plant water relationship and plant chemical composition of potato (Mondial cv.) under clay soil conditions using flood irrigation system. These treatments were arranged in a split split plot design with three replicates. Planting date was arranged in the main plots, irrigation water quantities were in the sub plots, while foliar spray treatments were randomly distributed in the sub sub plots.The obtained results indicate that, the tertiary interactions of planting on 10 th Oct., irrigation at 100 % of FC and spraying potato plants with calcium and boron in combination gave the highest values of plant height , both fresh and dry weight of shoot/ plant, total and free water % as well as total chlorophyll ( a+b) in leaf tissues, N, P, K, Ca , Boron and total carbohydrates contents in shoots in both seasons. While the tertiary interactions of planting on 20 th Sep., irrigation level at 50 % from FC and unsprayed with calcium and boron gave the highest values of bound water % and proline amino acid in leaf tissues in both seasons.
FAWZY MANSOUR & HANAN ABU EL-FOTOHConclusively, under similar conditions it could be concluded that , the tertiary interaction of planting on 10 th Oct , irrigation at 100 % FC and sprayed plants with Ca + B were the best interaction treatments for enhancing plant growth and chemical constituents in shoot of potato grown in clay soil under the same conditions.