Effect of rhizobial strain on lentil N2-fixation and yield

Non-Peer Reviewe

The effect of inoculation on yields of grain legumes

Non-Peer Reviewe

Nitrogen fixation of several grain legumes in Saskatchewan

Non-Peer Reviewe

Increased dry matter yield of alfalfa following inoculation with plant growth promoting rhizobacteria

Non-Peer Reviewe

Colonization of the alfalfa rhizosphere by plant growth promoting rhizobacteria

Non-Peer ReviewedPlant growth promoting rhizobacteria (PGPR) were evaluated for their ability to colonize the alfalfa rhizosphere and increase dry matter yield of alfalfa. Field trials at Beaverlodge, AB., Sun Prairie, WI. and Outlook, SK. demonstrated that PGPR's Pseudomonas 31-12 (Ps.) and Serratia 2-68 co-inoculated with Rhizobium meliloti increased the dry matter yield by 11, 9 and 7%, respectively. In the first year of a three year field study planted in May 1993 at Outlook, the effect of formulation carriers on colonization of the alfalfa rhizosphere by spontaneous rifampicin resistant mutants (rif+) of PGPR's Ps. 31-12 and Serratia 2-68 was measured. No rif+ microorganisms were detected in the rhizosphere of uninoculated alfalfa. plants. Ps. 31-12 was the better colonizer of the rhizobacteria examined with populations exceeding 1 o6 cells per root 169 days after planting. The population of Ps. 31-12 was 10 times greater 35 and 169 days after planting in the peat formulation than in the clay formulation. Similarly, the population of Serratia 2-68 in the alfalfa rhizosphere was 1000 times greater in the peat formation than in the clay formulation. The populations of these microorganisms will be measured over the next two growing seasons

Liquid rhizobial inoculants for lentil and field pea

Non-Peer ReviewedThe traditional peat legume inoculants are viewed by western Canadian farmers as being difficult to apply. Accordingly, more "user-friendly" inoculants are being developed to ensure more wide-spread inoculation of legumes. A liquid inoculant developed by LiphaTech was evaluated as a carrier for Rhizobium leguminosarum strains 99A1 for lentil and 128C56G for pea. These two strains survived at titres exceeding log 8.0 per mL for ten months at 5°C and there was no loss of viability during shipping and handling. The Prairie Agricultural Machine Institute (PAMI) determined that the liquid inoculant gave a very flowable and uniform coverage of the seeds when applied through a grain auger and various types of seeding equipment. Liquid inoculant for pea and lentil resulted in yields equal or better than those observed for the traditional peat-based inoculant

Influence of growth factors on the plant pathogens by select suppression of Pseudomonads

Non-Peer ReviewedRhizobacteria were evaluated for their ability to inhibit the growth of damping-off pathogens such as Pythium ultimum, Rhizoctonia solani and common root rot pathogen, Cochliobolus sativus. The level of antagonism by Pseudomonads 63-28, U-14 and Ral-3 was examined on solid growth media under varying conditions of temperature, pH, and sources of C, N, and amino acids. In vitro antibiosis of the pathogens was greatly influenced by environmental and nutritional conditions. Generally, antagonism was greatest at 25-300C and decreased at 400 C. The influence of pH appears to be rhizobacteria and pathogen dependent. For example, optimum inhibition of P. ultimum growth by 63-28 was between pH 4.6-6.0, whereas, optimum inhibition of R. solani growth by U-14 was at 7.6-9.1. Growth inhibition of C. sativus by Ral-3 was pH independent. Mannitol or trehalose strongly enhanced the antifungal activity of 63-28, whereas lactose had a negative effect. Antagonism of 63-28, U-14 and Ral-3 was enhanced by nitrogen sources tested except NaNO2 on U-14. The influence of the amino acids did not effect Ral-3, but, antibiosis by 63-28 was increased by amino acids phenylalanine, arginine, or histidine. U-14's activity was increased with the addition of proline, serine, or arginine. The results from this study clearly show that growth factors have a significant impact on microbial antagonism

Rhizobacterial influence on healthy stand establishment of canola grown in Rhizoctonia solani infested fields of Saskatchewan

Non-Peer ReviewedPre-emergence seedling damping-off, seedling blight, and brown girdling root rot caused by R. solani are important diseases of canola/rape seed in western Canada. Annual yield losses in excess of 20-30% have been reported in several infected fields. Cultural control methods or resistant cultivars are currently unavailable for these diseases. Chemical fungicides have been developed for use to control the disease, but the success rate has been varied. However, the use of chemicals is becoming less acceptable from an environmental point of view. Several studies indicated that biological control using plant growth promoting rhizobacteria may also be effective in controlling R. solani. Field plots were established in Saskatoon, Regina and Melfort, SK, in 1990, 1991 and 1992 to evaluate the potential of rhizobacterial strains as seed treatments to increase the healthy stand of canola CV. Westar grown in R. solani infested field. The bacteria were formulated either in sterile peat or in a liquid carrier and applied to seed just before planting. Bacterized seed were mechanically planted in replicated field plots artificially infested with R. solani. Final healthy stand was measured 30 days after planting. Grain yields were determined by harvesting the plots. Seed bacterization significantly increased the final healthy stand compared to non-bacterized controls. Strains which increased stand showed in vitro antagonistic activity to not only R. solani but also other pathogens such as Pythium ultimum, Fusarium solani and F. oxysporum. Some of these strains induced root elongation of canola under laboratory conditions. Rhizosphere colonization, chemical compatibility and shelf-life of the important bacteria will be discussed