The Effect of Plant Growth Promoting Bacteria on Transplants Growth and Lettuce Yield in Organic Production

Abstract

Application of beneficial bacterial strain B125 (Enterobacter sp.) and strain PZ9 (Bacillus sp.) in lettuce transplants production significantly enhanced seed germination and plant biomass. The best effect was obtained when the mixture of B125 and PZ9 was used. Combined application of these bacteria significantly increased transplants biomass, which was about 45% higher than that in the control. However, after planting these transplants in organic field, generally, there were no differences in yield and nutrient content in plants treated and not treated with the bacteria, except for nitrogen and vitamin C. The lettuce grown from transplants treated with bacterial mixture B125 + PZ9 contained significantly higher nitrogen than plants from other treatments. Opposite to nitrogen, bacterial applications decreased the amount of vitamin C. The growth and organic lettuce composition was affected by planting time. The yield was higher in spring, but the concentration of nutrients in these plants was lower than that in plants harvested in autumn. Climatic and light conditions in the late season were the reasons for increased dry matter content, minerals, phenolic compounds, and vitamin C, as well as high concentration of nitrates.

The productivity and quality of Lactuca sativa as influenced by microbiological fertilisers and seasonal conditions

“…In the control treatment, the highest vitamin C content was measured in autumn (short day). Similar results, where the highest vitamin C content in lettuce head was obtained in the control treatment, were significantly different from the treatment with bacterial strains (Szczech et al, 2016). This result is in contradiction with the results of Fu et al (2017), which imply that vitamin C content is increased with a high light intensity.…”

“…The application of two Trichoderma harzianum strains (T969 and T447) showed a higher concentration of phosphorus (P) and potassium (K + ) in the shoots and roots of tomato seedlings (Azarmi et al, 2011). A synergistic effect of two bacterial strains stimulated nitrogen uptake by plants treated with microbiological fertilisers as transplants (Szczech et al, 2016).…”

“…Effective microorganisms are a mixed culture preparation of beneficial microorganisms that can be found in nature containing photosynthetic bacteria, lactic acid bacteria, yeasts, actinomycetes and fungi (Wołejko et al, 2016). They can be used as inoculants to increase the diversity of microflora and influence physical and chemical characteristics of soil, decompose organic matter, stimulate plant growth and yield, decrease effects of monoculture, protect plants from diseases and help remove physiological disorders in plants (Szczech et al, 2016).…”

“…Bacterial-algal fertiliser led to a significantly increased rosette fresh weight in leaf and romaine lettuce during spring and summer seasons, a higher total antioxidant capacity in summer romaine production compared to control plants, contributing to enhanced heat stress protection in romaine lettuce (Kopta et al, 2018). Being similar to plants, microorganisms have particular demands for environmental factors as well as certain limitations towards plants and production methods (Szczech et al, 2016).…”

Multispecies Bacterial Bio-Input: Tracking and Plant-Growth-Promoting Effect on Lettuce var. sagess

“…This intensive system of lettuce production has a high demand for nutrients in the form of fertilizers and agrochemicals to avoid pests and diseases in both crop stages [ 22 ]. It has been reported that lettuce crops show a favorable response after inoculation with a single or a mixture of PGPB of different genera such as Azospirillum , Azotobacter , Pseudomonas , Rhizobium and Bacillus , among others [ 18 , 23 , 24 , 25 , 26 , 27 ], even in combination with fungi [ 28 ]. Such treatments led to larger plants with more biomass, but other aspects also were affected, such as the germination rate.…”