King, Jacqueline D2008-12-312013-12-312008-12-31bibid: 6477977https://hdl.handle.net/1813/11666Papaya (Carica papaya) cultivation is currently widespread throughout Bangladesh. The average fruit yield is extremely low (i.e., 6.6 t ha-1) and is most likely the result of plant disease (e.g., papaya ringspot virus), flooding, lack of varieties, and poor nutrient management. Over a two and one-half year period, eight field experiments were conducted at two different locations (i.e., Rangpur and Pabna area) in Bangladesh. In Rangpur, the objective of these experiments was to evaluate the effect of lime, poultry manure, and planting date on plant nutrition, soil fertility, and papaya production and availability. In the Pabna area, the objective of these experiments was to determine the effect of poultry manure, Zn, and B on plant nutrition, soil fertility, and papaya yield. In addition, the vitamin content of ripe papaya from both locations was determined. The experimental design for each of the experiments was a randomized complete block design with four replications. In Rangpur, the application of poultry manure substantially increased papaya yield. Manure application also generally increased the soil concentration of P, Ca, Mg, and Zn and the petiole concentration of P, Ca, Mg, and K. In contrast, the application of poultry manure lowered the soil concentration of Al and the petiole concentration of Mn and Zn. The application of lime had a very limited effect on yield, plant nutrition, and soil properties. In Rangpur, papaya that was transplanted in the fall provided ripe fruit approximately four to eight weeks earlier than papaya transplanted in the spring. In the Pabna area, even though the application of poultry manure tended to improve the soil fertility at this location, the application of poultry manure, Zn, and/or B had a very limited effect on crop yield. Overall, there was very little difference in vitamin content among the treatments for either location, however, the papaya fruit from Rangpur tended to have higher vitamin content as compared to fruit from Pabna. In conclusion, the results from this study suggest that a combination of nutrient management and planting date has the potential to improve the production and availability of papaya in Bangladesh.en-USPapayaBangladeshdissertation or thesis