Response of groundnut (Arachis hypogaea L.) varieties to rhizobia inoculation in the Sudan and northern Guinea savannas of Nigeria

Field trials were conducted in 2015 and 2016 seasons to evaluate the response of groundnut (Arachis hypogaea L.) varieties (KAMPALA, KWANKWASO, SAMNUT 21, SAMNUT 23, SAMNUT 24, and SAMNUT 25) to rhizobial inoculation treatments (rhizobium strains NC 92, SBG 234, MJR 518, WDL 129, +N (20 kg N ha-1), and -N (Control)) in the Sudan and northern Guinea savannas of Nigeria. Results of the 2015 trials were reported in Podcaster 39. The results obtained in 2016 showed similar trends to 2015. Analysis of the two seasons data showed that none of the inoculation treatments had significant (p ≤ 0.01) effects with respect to all variables measured1 except shoot dry weight per plant in both locations, haulm yield per ha in Sudan savanna (SS) in 2015, and number of nodules per plant in both locations in 2016. However, the varieties significantly differed (p ≤ 0.01) in all variables measured except nodule dry weight per plant and root dry weight per plant in northern Guinea savanna (NGS) in 2015, and number of nodules per plant in both locations in 2016. The interaction between variety and rhizobia inoculation was only significant on haulm yield per ha in SS in 2015 (Figure 1) and nodule dry weight per plant in NGS in 2016 (Figure 2). SAMNUT 24 was the best variety across locations and in both seasons even though there was no significant relation between inoculation and yield. However, SBG 234 and WDL 129 showed some potential of being selected as inoculant based on the shoot dry weight results from 2015 and the number of nodules per plant in 2016. Furthermore, the result of the interaction (Figure 2) also indicated high performance of the strains.

The field work is completed and laboratory analyses on soil and plant samples are in progress to determine biological nitrogen fixation potentials and soil N balance with respect to the varieties used in the study. Meanwhile, a paper has been submitted for presentation at Crop Science Society of Nigeria (CSSN) Conference for sharing the information of the research with fellow scientists for further collaboration in the field of Rhizobiology. Furthermore, I have started writing my thesis and seminar papers from the results obtained so far.

Figure 1: Interaction effect of groundnut variety and rhizobia inoculation on haulm yield
Figure 1: Interaction effect of groundnut variety and rhizobia inoculation on haulm yield


Figure 2: Interaction effect of groundnut variety and rhizobia inoculation on nodule dry weight

Faruk Galadanchi Umar, Bayero University, Nigeria (Click here for his 2016 update)


1chlorophyll content; number of nodules per plant; nodule dry weight per plant; root dry weight per plant; shoot dry weight per plant; pod yield per ha; kernel yield per ha; shelling percentage; hundred seed weight; haulm yield per ha; and harvest index

Newsletter #: 
47
Newsletter item #: 
3
Country: 
Nigeria