A.I. Gabasawa*1, A.A. Yusuf1, E.N.O. Iwuafor1 and C.A. Echekwu2
1Department of Soil Science, Faculty of Agriculture/Institute for Agricultural Research, Ahmadu Bello University, P.M.B. 1044, Samaru, Zaria, Kaduna State, Nigeria.
2Department of Plant Science, Faculty of Agriculture/Institute for Agricultural Research, Ahmadu Bello University, P.M.B. 1044, Zaria, Kaduna State, Nigeria.
*Corresponding Author: E-mail: firstname.lastname@example.org
Photosynthesis and biological nitrogen fixation are two vital biochemical processes for the growth, development and yield of a leguminous crop. The plants can require large amounts of P for effective fixation. Under deficient conditions, P fertilization will result in improved nodulation and enhanced N2-fixation. A field trial was conducted in 2015 cropping season in the Institute for Agricultural Research experimental field, Ahmadu Bello University, Zaria, Nigeria. The study was aimed at determining the symbiotic nitrogen fixation potential of groundnut genotypes grown on an Alfisol. The treatments consisted of 16 groundnut genotypes and 3 P sources. The P sourced was in the main plot with genotype in the sub-plot of a split plot design that was replicated four times. More chlorophyll content (CC) was recorded by ICGV-IS 07815, and together with ARRORS ICGX 000201/5/P4/P10 and SAMNUT 21 the highest haulm yield. The lowest content was recorded by ICIAR 7B. Genotypes ICIAR 6AT, ICIAR 7B, Kwankwaso and SAMNUT 10 recorded the lowest haulm yield. All the genotypes were at par in terms of number of nodules, but they were statistically different in their nodule weights. Two (RP and SSP) of the P sources contributed, to nodule weight and haulm yield, statistically better than the other (0) source. There was, however, no statistical difference between all the P sources in terms of nodule number. Further studies at multi-locations level and attempting to understand the P use mechanisms involved will allow for a better understanding of the genotypic potentials.