Rhizobium inoculant formulation and placement in lentil and chickpea in the semiarid Canadian prairies

Non-Peer ReviewedLentil and chickpea are the major pulse crops grown in western Canada, but little is known about the responses of these annual legumes to rhizobium inoculant formulation, placement, and their interaction to fertilizers under semiarid environments. A field study was conducted from 1999 to 2002 on a medium-textured soil at Swift Current and on a heavy clay soil at Stewart Valley, both in Saskatchewan. The objectives were to (i) determine the effects of rhizobium inoculation and fertilization on nodule formation, N2-fixation, and their impacts on growth, yield, and seed quality in chickpea and lentil, and (ii) develop recommendations for optimizing rhizobium inoculation, P-solublizing inoculation, and fertilizer N and P application for direct-seeding of chickpea and lentil with 1-, 2-, and 3-tank delivery systems. The results of the six site-years showed that use of rhizobium inoculation increased seed yield by 35% for desi, 7% for kabuli, and 23% for lentil. Inoculation reduced desi plant population by 10%, but not in kabuli or lentil. Granular inoculant increased yield by 7% in chickpea and 8% in lentil, compared to peat-based powder inoculant. Placement of granular inoculant (seed-row vs side-banding) had the same effect in all three pulses. Starter-N and starter-P at a rate of 15 kg ha-1 each had a marginal effect on plant growth and seed yield, but a higher rate of P (34 kg P2O5 ha-1) increased kabuli seed size. Chickpea and lentil did not show any response to Penicillium bilaii (fungus contained in the products JumpStart® and TagTeam®) under the semiarid growing conditions