Bacterial inoculation positively affects the quality and quantity of flax under deficit irrigation regimes

Abstract

Aim The present research was conducted to investigate the effect of plant growth‐promoting rhizobacteria (PGPR) and deficit irrigation on quality and quantity of flax under field and pot conditions to determine bacterial efficiency and to decrease water deficit effects. Methods and Results Initially, in vitro experiments were performed to determine the growth‐promoting characteristics of bacteria. Then in the field, the effects of bacterial inoculation (control, Azotobacter chroococcum, Azospirillum lipoferum, Bacillus amyloliquefaciens, Bacillus sp. strain1 and Pseudomonas putida) on flax traits were evaluated at different irrigation levels (100, 75 and 50% crop water requirement). Bacterial treatments in the pot experiment were selected based on the field experiment results. The irrigation regimes in the pot and field experiments were the same and bacterial treatments included single, doublet and triplet applications of the bacteria. All the bacterial strains could solubilize phosphate, produce ammonia (except for Bacillus sp. strain1), indole acetic acid and siderophore (except P. putida). Field results indicated that the bacteria significantly mitigated the effects of water deficit. Compared with control plants, bacterial treatments increased the oil, linolenic acid, protein and sulphur content; the number of shoots and capsules; and the harvest index in the flax plants. Pot experimental results revealed that the combined inoculations were more effective than single inoculum treatments. Conclusions Bacterial inoculation alleviates deficit irrigation effects in flax plants. Significance and Impact of the Study The effectiveness of applying A. chroococcum, B. amyloliquefaciens and Bacillus sp. strain1 was confirmed, especially as a combination to protect flax against water deficit and to improve its nutritional quality and growth.

Exploiting Beneficial Pseudomonas spp. for Cannabis Production

“…While these quantitative and qualitative improvements are part of ongoing cultivar breeding objectives, the use of Pseudomonas spp. inoculants constitutes a promising complimentary approach, as demonstrated in other oilseed crops including sesame (Kumar et al, 2009), sunflower (Majeed et al, 2018), flax (Rajabi-Khamseh et al, 2020), soybean, canola, and corn gromwell (Jiménez et al, 2020) where increased seed yield, oil yield and/or composition in desirable fatty acids were reported. Additionally, more research is still needed to investigate the largely unknown mechanisms resulting in these alterations of seed oil content and composition by PGPR.…”