The present work was designed to study the effect of different schedules of
,; irrigation (every 3, 4 and 5 days as drip irrigation) and fertilizer (NPK 19:19:19) at 1.5,
3 and 4.5g/pot as liquid with the irrigation water on growth of Cycas revo/uta seedlings
during the two periods in 2003 / 2004 in the green-house at Antoniades Branch, Hort .
. Res. Inst., A.R.C. Alexandria. Egypt. The results indicated that different irrigation intervals had insignificant effects
on growth of Cycas seedlings during the two experimental periods (15 and 20
months). However, the highest values of stem characters were observed with
irrigation every 3 and 4 days after 20 months. Concerning the chemical fertilizer rate, the most satisfactory results for the
growth of Cycas revo/uta seedlings was observed with using the lowest fertilizer rate
(1.5g/plant) every 2 weeks during the growing season. Considerinq, the important rate
of Cyanobacteria (Nostoc) as a nitrogen fixing symbiosis which leave in association
with Cycas plants in a modified roots called coralloid roots. The high rates of fertilizers
had negative effects on both the plant growth and Cyanobacteria. In general, drip irrigation system every 4 days (with rate equal to 33% of the
field capacity) and applied with 1.5g/plant of chemical complete fertilizer every 2
weeks during the growth of Cycas revo/uta, is the best treatment to grow Cycas
seedlings in the green-house.