A field experiment was conducted at National Citrus Research Program, Paripatle, Dhankuta
during 111 November, 2004 to t" September, 2005 to determine the effect of different doses of GA1
and nitrogen under open and plastic tunnel condition on growth of trifoliate orange seedling. The
experiment was laid out in two factorial split-plot design consisting three replications of each
treatment. The open and plastic tunnel was considered as the main plot factor (Factor-A) and the
combination of different doses of gibberellic acid (GAJ) and nitrogen as sub plot factor (Factor-B).
The treatments were applied in seedlings two months after germination. Seedlings were planted at
J5x/O em spacing in 90 cmx80 em sized experimental plots supplied initially with 5 kg FYM per
plot containing 48 plants. White transparent plastic sheets were used for covering the plant in the
form of tunnel. GAJ was applied as foliar spray at one month intervals while nitrogen was applied
through urea as soil application at two split doses in I'' April and I'' May. Ten sample plants were
selected for the study from each bed From the study, it was found that the growth of seedling of
trifoliate orange was highly accelerated under the plastic house condition as compared to the open
condition. The height of seedling (47.75 em). number of leaf per plant (25.27) and size of seedling
diameter (5. 193 mm) were found highest at 300 days after sowing under plastic tunnel condition.
Similarly, the highest growth of seedling height (48.8/ em), number of leaf per plant (27.20) and
seedling diameter (5.383 mm) were observed in 120 ppm GA1 and 400 kg nitrogen/ha combination
at similar age of the seedling.

A field experiment was conducted at National Citrus Research Program, Paripatle, Dhankuta
during 111 November, 2004 to t" September, 2005 to determine the effect of different doses of GA1
and nitrogen under open and plastic tunnel condition on growth of trifoliate orange seedling. The
experiment was laid out in two factorial split-plot design consisting three replications of each
treatment. The open and plastic tunnel was considered as the main plot factor (Factor-A) and the
combination of different doses of gibberellic acid (GAJ) and nitrogen as sub plot factor (Factor-B).
The treatments were applied in seedlings two months after germination. Seedlings were planted at
J5x/O em spacing in 90 cmx80 em sized experimental plots supplied initially with 5 kg FYM per
plot containing 48 plants. White transparent plastic sheets were used for covering the plant in the
form of tunnel. GAJ was applied as foliar spray at one month intervals while nitrogen was applied
through urea as soil application at two split doses in I'' April and I'' May. Ten sample plants were
selected for the study from each bed From the study, it was found that the growth of seedling of
trifoliate orange was highly accelerated under the plastic house condition as compared to the open
condition. The height of seedling (47.75 em). number of leaf per plant (25.27) and size of seedling
diameter (5. 193 mm) were found highest at 300 days after sowing under plastic tunnel condition.
Similarly, the highest growth of seedling height (48.8/ em), number of leaf per plant (27.20) and
seedling diameter (5.383 mm) were observed in 120 ppm GA1 and 400 kg nitrogen/ha combination
at similar age of the seedling.