Two field experiments were carried out at 8assyoun centre , Gharbia
Governorate during the two successive seasons 2003 and 2004. These experiments
were conducted to evaluate the effect of two foliar sprays of boric acid at two levels
i.e. 0.15 and 0.3% at each spray , K2S04 at two levels l.e. 1 and 2% K20 at each
spray and a bioregulator SGA-1 at two levels l.e. 0.2 and 0.4% at each spray in
comparison with spraying water as a control. The leaf nutrients content, growth traits,
boll set attributes, earliness, seed cotton yield and its components of the Egyptian
extra long staple ( Gossyp < /em>ium barbadense L.)Giza 88 cotton cultivar were measured.
The leaf Nand P contents were significantly increased due to ·the,different
spraying treatments where these contents reached their highest averages due to the
foliar application of SGA-1 followed by the high level of boron. The same treatments
recorded a high K and Ca contents and the highest Fe, Mn and Zn contents.
Foliar application of SGA-1 was effective to enhance cotton plant growth as
expressed in taller plants and larger number of sympodia and hence larger number of
bolls/plant than the control ones. These improvements were reflected in seed cotton
yield/fed.
Foliar application of boric acid at a level of 0.3% or potassium sulphate at a
level of 2% K20 was also effective in these respects but with lower averages than
those obtained due to the SGA-1 treatment.
The results concluded that two foliar sprays with a bioregulator SGA-1 at a
level of 0.4% at the beginning of flowering and 15 days later is the best treatment for
good growth and high productivity of the extra long staple , Giza 88 cotton cultivar.
Also. two foliar feedings with boron as boric acid at a level of 0.3% or potassium as
potassium sulphate at a level of 2% K20 could be used for high productivity