Abstract:
“Red Lady” is a popular hybrid papaya variety among the Sri Lankan papaya growers.
There is a general fertilizer recommendation in the Department of Agriculture for all the
papaya cultivars including variety Rathna. However, there is no fertilizer recommendation
for papaya hybrid varieties in Sri Lanka yet. Therefore with the objective of development
of an effective fertilizer formulation for hybrid papaya the present study was carriedout in
, r
the dry zone of Sri Lanka at Embilipitiya from September 2014 to August 2015. Ten
different fertilizer packages were applied as treatments. Recommended fertilizer NPK
(RF) mixture by using Urea as a N source given by DOA (Ti), RF mixture with Cow dung
(T2), RF mixture with Borax and ZnSCL (T3), RF mixture but N source Ca(N03)2 + Borax
and ZnSCL (T4), RF mixture but N source Nitrabor + ZnSCL (T5), RF mixture with Borax,
ZnSCL and Cow dung(T6), T4 with Cow dung (T7), T5 with Cow dung (Tg), T3 and T4
alternatively used (T9), T3 and T4 alternatively used with Cow dung (T10). Treatments were
laid according to Randomized Completely Block Design with three replications. Growth
and yield parameters were recorded up to eight months after planting.
Treatments T7 and T8 were shown the same trend on plant height and Tg; T9 showed the
same trend on Stem girth. Fertilizer packages did not show significantly affects to number
of leaves per plant and plant canopy width. The fruit yield per plant, fruit number per plant
and the total yield per hectare showed significant difference (P<0.05) in T10 fertilizer
package. It showed higher values than the others (Fruit yield/plant 17.870kg, fruit number
13fruits/plant and total yield 28.6mt/ha throughout the study period). Single fruit weight
(1.787kg) was significantly higher in the T4. The lowest cost of fertilizer for the treatment
were showed in Ti and T3 (Rs.2.07/kg) in that period. T2, T6, T9 and T10 were statistically
same with cost of fertilizer values (Rs/kg) are 6.03, 6.70, 7.64 and 8.37 respectively and
Profit percentage of that treatments were predicted for a year. They are 151%, 122%, 98%,
and 174% respectively. Among those treatments T10 is selected as the best fertilizer
package with considering highest percentage of profit.
From the overall studies, it was concluded that the best fertilizer package should be with
balanced fertilizer mixture with NPK and micro nutrients Zn, B with cow dung Ca (NO3L
and Urea should apply alternatively as nitrogen source to get higher profitable yield in
papaya cultivation.
