Improving quantitative and qualitative yield of canola by Pseudomonas fluorescens accompanied with chemical fertilizer

Canola (Brassica napus L.) is one of the important oil plants in temperate regions, which has great value for humans and livestock as a producer of oil and meal. Phosphorus plays an important role in improving the quality and quantity of oilseeds, including rapeseed. Sufficient sources of phosphate are needed by the plant for earlier development and rooting and more foliage production in a short period of time. Considering the stabilization of phosphorus in the soil, the increase in the price of chemical fertilizers and environmental pollution, the use of biological fertilizers, especially the types of phosphorus-dissolving bacteria, play an important role in solving these problems. Therefore, the objective of this research was to investigate the role of phosphorus biofertilizer containing Pseudomonas fluorescens bacteria in improving the quantitative and qualitative yield of canola under the influence of chemical phosphorus fertilizer management.

A factorial field experiment was conducted based on a randomized complete block design with three replications at the research station of the Faculty of Agriculture of Yasouj University located in Deshtrum region in 2019. The first factor was triple superphosphate fertilizer at 6 levels (zero, 25, 50, 75, 100 and 125 kg/ha of pure phosphorus) and the second factor included phosphorus biological fertilizer containing Pseudomonas fluorescens bacteria at two levels (application and non-application). The traits of yield components, seed and biological yield, and seed oil and protein were evaluated. The traits of yield components, seed and biological yield, and seed oil and protein were evaluated. Yield components, seed and biological yield, and seed oil and protein were evaluated.

The results showed that phosphorus and bacteria chemical fertilizers had a significant effect on all investigated traits. The interaction of phosphorus chemical fertilizer and bacteria was also significant on all investigated traits except harvest index. The highest plant height (124.93 cm), number of lateral branches (4), leaf chlorophyll index (74.20), seed yield (5887 kg/ha) and biological yield (19411.4 kg/ha) were obtained in the treatment of 125 kg/ha of phosphorus and bacterial application. Also, with the consumption of 125 kg/ha of phosphorus fertilizer and the use of bacteria, the highest percentage and oil yield was obtained. Also, the results showed that there is no significant difference between the treatment of application of 50 kg of phosphorus fertilizer + bacteria and the treatments of application of higher levels of phosphorus fertilizer (75, 100 and 125 kg) alone.

Considering the superiority of 125 kg of phosphorus fertilizer along with bacteria in terms of grain yield, oil percentage and oil yield, it seems that these amounts of phosphorus fertilizer as well as the use of bacteria can be used to achieve proper yield in the experimental and also similar areas. Also, the results show that using bacteria can reduce the consumption of phosphorus chemical fertilizers.