Rhizobium population dynamics in the pea rhizosphere of rhizobial inoculant strain applied in different formulations

Field pea has been shown to benefit from the use of rhizobium inoculation and seed-applied fungicides under intensive production. The objective of this research was to determine the effect of seed- or soil-applied rhizobium (Rhizobium leguminosarum bv. viciae) inoculants and seed-applied fungicides on field pea (Pisum sativum “Carneval”) production on fields with no previous history of the crop. The study was conducted at seven locations in Saskatchewan in each of 2 yr. Fungicide treatments were Apron FL (metalaxyl), Apron FL + Thiram 75WP (dithiocarbamate) and an untreated check in 1997 and a fourth treatment, Thiram 75WP, was added in 1998. Rhizobium treatments were seed-applied liquid inoculant, soil-applied granular inoculant and a non-inoculated check. Inoculation with rhizobium increased nodulation (5 of 10 sites), seed yield (6 of 13 sites), and protein content (3 of 8 sites), but occasionally appeared to reduce emergence (3 of 14 sites). Granular inoculant had more beneficial effects than the liquid inoculant. Fungicide treatments had few positive effects on production, and occasionally negative effects such as reduced emergence. Interaction effects were rare between seed-applied fungicide and seed-applied liquid or soil-applied granular rhizobium inoculants, which indicated compatibility of these products. Variability in the effects of inoculant types and fungicides suggests that responses are dependent on local soil and environmental conditions. Key words: Apron (metalaxyl), Thiram (dithiocarbamate), Pisum sativum, zero tillage

Section: Discussionsupporting

confidence: 82%

Section: Discussionmentioning

confidence: 97%

Rhizobium inoculant and seed-applied fungicide effects on field pea production

Kutcher¹,

Lafond²,

Johnston³

et al. 2002

“…Desi chickpea grown on the clay produced 37% more root nodules and 75% greater nodule mass measured at flowering than when grown on the silt loam soil under comparable growing conditions. Hynes et al (2001) observed that colonization of the rhizosphere of dry pea was significantly reduced when soil moisture was low. Postma et al (1989) observed better survival of Rhizobium in fine-textured than in coarse-textured soils.…”

Section: Seed Yieldmentioning

confidence: 88%

Effect of formulation and placement of Mesorhizobium inoculants for chickpea in the semiarid Canadian prairies

Gan¹,

Selles²,

Hanson³

et al. 2005

. 2005. Effect of formulation and placement of Mesorhizobium inoculants for chickpea in the semiarid Canadian prairies. Can. J. Plant Sci. 85: 555-560. The use of bacterial inoculants can increase root nodulation and the seed yield of annual legumes. A six site-year study was conducted to determine the effect of formulations (peat-based powder vs. granules) and placement in the soil (seed-row vs. side-band) of Mesorhizobium inoculants on plant establishment and seed yield of chickpea (Cicer arietinum L.) in the semiarid Canadian prairies. Two market classes of chickpea, namely desi and kabuli, were grown on silt loam and heavy clay soils in southwestern Saskatchewan from 1999 to 2002. Inoculation reduced plant population by 10% for desi chickpea, but had no effect on kabuli chickpea. However, the use of inoculant increased seed yield by an average of 35% for desi chickpea and 7% for kabuli chickpea. On the heavy clay, soil inoculation increased seed yield by 16% for desi and 9% for kabuli compared with seed inoculation, whereas the yield increase due to soil inoculation, over seed inoculation, was 3% when the crops were grown on the silt loam. Granular inoculant applied in the seed row produced similar seed yields to side-banded inoculant. Inoculation delivery systems had a marginal impact on plant height, with no effect on the lowest pod height from the soil surface or days to maturity. Regardless of placement, soil inoculation with a granular form of Mesorhizobium was preferred over seed inoculation because of its greater positive impacts on plant establishment and seed yield for both desi and kabuli chickpea in this semiarid region. Les inoculants bactériens peuvent accroître la nodulation et le rendement grainier des légumineuses annuelles. Les auteurs ont entrepris une étude de six années-sites pour vérifier l'incidence de la formule (poudre à base de tourbe ou granules) et de la méthode de placement (avec la planche de semis ou en bande latérale) des inoculants de Mesorhizobium sur l'établissement et le rendement grainier du pois chiche (Cicer arietinum L.) dans la région semi-aride des Prairies canadiennes. Ils ont cultivé deux variétés marchandes de pois chiche (desi et kabuli) sur un loam limoneux et sur de l'argile lourde dans le sud-ouest de la Saskatchewan de 1999 à 2002. L'inoculation diminue la densité de peuplement du pois chiche desi de 10 %, mais n'a aucun effet sur le pois chiche kabuli. L'usage d'un inoculant accroît cependant le rendement grainier d'en moyenne 35 % pour le pois chiche desi et de 7 % pour le pois chiche kabuli. Sur l'argile lourde, l'inoculation du sol relève le rendement grainier de 16 % pour le pois chiche desi et de 9 % pour le pois chiche kabuli, par rapport à l'inoculation des semences, mais quand le pois chiche est cultivé sur du loam limoneux, l'inoculation du sol n'augmente le rendement que de 3 % comparativement à l'inoculation des semences. L'application d'un inoculant granulaire à la planche de semis donne un rendement grainier similaire à l'application en bande lat...

“…In field experiments conducted in Alberta and Saskatchewan, the survival of R. leguminosarum bv. viciae on pea seed soon after inoculation and colonization of the rhizosphere of pea plants were clearly shown to be lower with liquid inoculant than with peat inoculant or granular inoculant under excessive soil moisture conditions (Hynes et al 2001).…”

Section: Nodulationmentioning

confidence: 93%

Inoculant formulation and fertilizer nitrogen effects on field pea: Nodulation, N₂ fixation and nitrogen partitioning

Clayton¹,

Rice²,

Lupwayi³

et al. 2004

. Inoculant formulation and fertilizer nitrogen effects on field pea: Nodulation, N 2 fixation and nitrogen partitioning. Can. J. Plant Sci. 84: 79-88. Field pea (Pisum sativum L.) acreage has expanded rapidly in the past 10 yr in the Peace River Region of Alberta as well as western Canada. Understanding nitrogen dynamics of Rhizobium inoculants and applied N will provide farmers opportunities to improve N nutrition of field pea. Field experiments were conducted (a) to compare the effects of soil inoculation using granular inoculant, and seed inoculation using peat powder and liquid inoculants with an uninoculated check, on field pea nodulation and N 2 fixation, and (b) to determine whether starter N is required by field pea to enhance N 2 fixation. The effects of inoculant formulation on nodule number, N accumulation and N 2 fixation were in the order: granular > peat powder >liquid = uninoculated. Field pea, from soil-applied inoculant, accumulated more N prior to and during podfilling than field pea with seed-applied inoculant. Fertilizer N application rates < 40 kg N ha -1 had no significant effects on biomass N at flatpod, indicating that starter N was not necessary. Application rates greater than 40 kg N ha -1 reduced nodulation, but the total amounts of N accumulated by plants did not vary. The close proximity of a highly concentrated band of N fertilizer had a greater impact on nodulation and subsequent N 2 fixation than the residual soil N level. Under field conditions, soil-applied inoculant improved N nutrition of field pea compared to seed-applied inoculation, with or without applied urea-N. Quand l'inoculant est ajouté au sol, le pois accumule plus d'azote avant et pendant le remplissage des gousses que lorsque l'inoculant est appliqué avec la semence. L'engrais azoté n'a aucun effet sensible sur l'azote de la biomasse au stade de la gousse vide quand le taux d'application est inférieur à 40 kg de N par hectare, signe qu'un engrais de démarrage est superflu. Aux taux plus élevés, l'engrais nuit à la nodulation, mais, au total, les plantes accumulent la même quantité d'azote. La proximité d'une bande d'engrais azoté très concentré agit plus sur la nodulation et sur la fixation subséquente de l'azote que les résidus d'azote dans le sol. Dans des conditions normales au champ, l'addition d'un inoculant au sol répond mieux aux besoins azotés du pois que l'application d'un inoculant avec la semence, avec ou sans urée.