This investigation was carried out aiming to study the effect of
irrigation intervals ( every 7 , 11 and 15 days) and Biofertilization ( nitrobien
and phosphorein each at 0 , 3 and 6 g /pot) on growth, yield, oil production
and chemical composition of rosemary (Rosmarinus officinalis, L.), during
two successive seasons of 2004 and 2005.
The results showed that irrigation every 7 days gave the tallest plant,
the highest oil percentage and oil yield/ plant in the first cut of both two
seasons, the highest number of branches/ plant, fresh and dry weights/plant,
total carbohydrates , N, P and K percentage in the first and second cut of
both seasons and gave the highest linalool and P-cymene percentages in the
essential oil. Whereas irrigation every 11 days gave the tallest plant, the
highest oil percentage and oil yield/ plant in the second cut of both seasons
and the highest α-pinene, β-pinene, limonene, 1,8 cineol and camphor
percentages compared to irrigation every 15 days which gave the lowest
values.
Nitrobien and phosphorein at 3 and 6 gm/ pot significantly increased
plant height, number of branches/ plant, fresh and dry weights/ plant and oil
yield/ plant, and increased the main constituents of the essential oil (γ-
Terpenene, 1,8 cineol, linalool , camphor, P-cymene, bornyl acetate and β
caryophyllene percentages ), total carbohydrates, N, P and K contents in the
first and second cut of both two seasons compared to unfertilized control.
Interaction between irrigation intervals and bio-fertilization had a
significant effect on vegetative growth characteristics and oil percentage and
oil yield. Irrigation every 7 days and phosphorein at 6 g /pot gave the highest
values of plant height ( in the first cut), number of branches /plant ( second
cut), fresh and dry weights /plant ( in the first cut, oil yield /plant ( in the first
cut), total carbohydrates, N and P contents in the first and second cut of both
seasons. Whereas irrigation every 11 days and phosphorein application at 6 g
/pot gave the highest dry weight/ plant, oil percentage and oil yield/ plant in
the second cut of both two seasons. irrigation every 11 days and nitrobien
application at 3 g /pot gave the highest β-pinene, 1,8 cineol, camphor and
bornyl acetate percentages in the essential oil. Whereas irrigation every 11
646 EL-LEITHY ET AL
days and phosphorein at 3 gm/pot gave the highest linalool and P- cymene
percentages in the essential oil.