Response of Guava (Psidium guajava L.) Seedlings to Various Nitrogenous Fertilizers

Abstract

The response of guava seedlings to the application of various forms of nitrogenous fertilizers, namely, sodium nitrate, ammonium sulphate, ammonium nitrate, urea and azolon was studied under nursery conditions. The results revealed that increases in seedling height, stem diameter, number of leaves and fresh and dry weights of leaves, stems and roots were significantly higher in guava seedlings receiving different nitrogenous fertilizers than the control. Greater accumulation of fresh and dry weights of different tissues was associated with ammonium sulphate treatment compared to the other treatments. All nitrogenous fertilizers resulted in significantly higher leaf-N content than the control. Significantly higher leaf-N was detected in seedlings receiving urea, azolon or sodium nitrate than those receiving ammonium nitrate. No significant differences in leaf-N content between ammonium sulphate and sodium nitrate treatments were noted. Leaf-P, K, Mn and Cu contents were significantly higher in seedlings receiving various nitrogenous sources than the control. No significant differences were noted in leaf-P, K, Mg and Cu contents among nitrogenous fertilizers. Significantly lower leaf-Ca content was associated with various nitrogenous fertilizers compared to the control. Leaf-Zn content of azolon- or urea-treated seedlings was significantly lower than the other treatments. However, the highest leaf-Zn content was detected in sodium nitrate-treated seedlings.