AGRICULTURE AND BIOLOGY JOURNAL OF NORTH AMERICA Effect of different chemical fertilizers on growth, nodulation and yield of alfalfa under stress environment of Mecca District, KSA

ABSTRACT A study was conducted in Hada Al-Sham Research Station , King A/Aziz University in Jeddah, Saudi Arabia for two consecutive years (2009)(2010) to evaluate the effect of some chemical fertilizers (N, P, K, and NPK) on growth, nodulation and productivity of alfalfa grown under stress environment of irrigation water salinity and poor soil. The treatments consisted of N in the form of urea, P in form of superphosphate , K in form of KNO 3 and NPK, all applied at a rate of 50 kg/ha. Significant differences were reported for the fertilizer treatments for all parameters measured. NPK and P were effective in increasing shoot/root ratio, NPK and K in nodulation, NPK and N in productivity of fresh fodder. Nitrogen in form of urea increased forage yield over the control by 32% in year 1 and by 25% in year 2