Foliage applied boron along with boron-tolerant bacteria (Bacillus sp. MN54) ensures better nodulation, growth, grain yield and grains-B biofortification of chickpea

Abstract

Boron (B) deficiency is the leading constraints in chickpea production in calcareous soils; albeit the range between B deficiency and toxicity is very narrow. Boron-tolerant bacteria (BTB) can optimize plant functions under B-deficient conditions by improving its uptake and can also tolerate B toxicity. This two-year pot study was conducted to optimize the best level of B as foliar application along with BTB (Bacillus sp. MN54) inoculation to improve nodulation, yield and grain-B concentration of chickpea. Two sets of pots, one with BTB inoculation and other without BTB were prepared. Foliar treatments of B were applied to plants at concentrations of 0.000, 0.023, 0.046, 0.069, and 0.092 M while plants sprayed with distilled water were taken as control. Boron application improved root and growth-related traits, nodulation, yield-related traits and grains-B concentration compared with no B and water spray controls. Among levels tested, foliar application of 0.046 M B solution was better in improving root system, nodulation, yield-related traits; while higher B levels resulted more grains-B concentration. Seed inoculation with BTB further augmented chickpea productivity compared to non-inoculation controls. Foliar application of B (0.046 M) coupled with BTB enhanced number of grains per plant (40%), nodules population (60%) and grain yield (43%) compared with control. Lower levels of B (≤0.069 M) seemed good to improve yield-related traits while its higher levels improved grains-B concentration. In crux, foliar application of 0.046 M B solution along with seed inoculation with BTB (Bacillus sp. MN54) seemed a pragmatic option to improve nodulation, yield and grains-B concentration of chickpea.

KEYWORDS:

• foliar spray
• chickpea
• grains-B concentration
• nodulation
• number of pods per plant

Disclosure Statement

The authors declare no conflict of interest.

Author Contributions

Conceptualization, Mubshar Hussain and Tauqeer Ahmad Yasir; Formal analysis, Noman Mehboob; Funding acquisition, Mubshar Hussain; Investigation, Noman Mehboob and Tauqeer Ahmad Yasir; Methodology, Tauqeer Ahmad Yasir and Noman Mehboob; Project administration, Mubshar Hussain; Supervision, Mubshar Hussain and Tauqeer Ahmad Yasir; Validation, Noman Mehboob; Writing – review & editing, Mubshar Hussain and Tauqeer Ahmad Yasir. All authors have read and agreed to the published version of the manuscript.

Data availability statement

All relevant data are within the manuscript.

Additional information

Funding

The corresponding author (Dr. Mubshar Hussain) is highly obliged to the Higher Education Commission of Pakistan for financial assistance to accomplish this study under NRPU grant No. 6998/Punjab/NRPU/R&D/HEC/2017.