Effect of Foliar Spray with Salicylic Acid on Vegetative Growth, Stem and Leaf Anatomy, Photosynthetic Pigments and Productivity of Egyptian Lupine Plant (Lupinus termis Forssk.)

Field experiments were carried out at the Agricultural Experiments and Researches Station, Faculty of Agriculture, Cairo University, Giza, Egypt during the two winter growing seasons of 2012/2013 and 2013/2014 in order to study the influence of foliar spray with various concentrations of salicylic acid (0, 25, 50, 75, 100 and 150 ppm) on flowering onset, morphological characters of vegetative growth, stem and leaf anatomy, photosynthetic pigments, yield characters and seed quality of Egyptian lupine ‘Giza 2’. The obtained results revealed that the median used concentrations of Salicylic acid (SA) induced promotive effect on flowering onset, morphological characters of vegetative growth, photosynthetic pigments and yield characters as well as seed quality of Egyptian lupine ‘Giza 2’. The maximum significant promotion was obtained when plants of Egyptian lupine ‘Giza 2’ were sprayed with 75 ppm SA. This treatment elicited beneficial changes in both vegetative and reproductive characters, which resulted in higher yield of seeds/ plant. These plants were characterized by earliness in flowering and had longer height which developed more primary branches and higher number of pods having more number of seeds of high specific weight and high protein content and low alkaloidal content. Such treatment (75 ppm SA) promoted chlorophyll pigments in leaves and induced favorable changes in anatomical structures of vegetative growth. Foliar application with 75 ppm SA induced prominent increase in stem diameter due mainly to the prominent increases induced in thickness of stem wall and in diameter of hollow pith. The increase in stem wall thickness could be attributed to the induced increase in thickness of epidermis, cortex, fiber strands, phloem and xylem tissues as well as in thickness of parenchymatous area of the pith and in vessel diameter. Likewise, such treatment increased thickness of both midvein and lamina of leaflets of Egyptian lupine ‘Giza 2’ due to increase induced in thickness of both palisade and spongy tissues as well as to increase induced in size of midvein bundle.