A pot experiment was conducted in an open greenhouse to explore the use of citrate-coated cobalt ferrite nanoparticles (CoFe2O4 NPs) as a source for Fe fortification of three wheat lines (Triticum aestivum L.). Two of the three wheat lines tested differ in their efficiency concerning Zn storage in their grains (efficient and inefficient), and one had inefficient P-absorption. The NPs were supplied by foliar or soil application of Fe at 330 mg L−1, and 46 or 68 mg kg−1 soil, respectively. A positive control (Fe-EDTA salt, a conventional iron fertilizer) and a negative control (no fertilization) were also included to compare the efficiency of NP fertilization. Soil fertilization with NPs improved the grain yield and Fe concentration in the grains compared with the foliar application of NPs and conventional Fe fertilizer. Application of soil NPs at 68 mg kg−1 increased the grain yield by 52% and 21% compared with the control and soil Fe-EDTA treatments, respectively. Likewise, grain Fe concentration increased by 96% and 72% compared with the control and soil Fe-EDTA treatments, respectively. The phytic acid concentration in grains and the phytic acid:Fe ratio decreased by 6% and 62%, respectively, due to the soil application of NPs (68 mg Fe per kg). The Fe grain concentration of lines inefficient for Zn storage and P-uptake in plants from soil fertilized with NPs (68 mg Fe per kg) was 1.37 and 0.26 fold above the target biofortification concentration (60 mg Fe per kg). Cobalt concentration in grains ranged from 9 to 16 mg kg−1. These concentrations were below the maximum allowable limit of Co in grains (50 mg kg−1) recommended by FAO and the WHO. Our results showed that Fe supplied as NPs may improve the nutritional quality of wheat grains, and the economic yield. However, there remains a long way to go to achieve effective and economic use of nanotechnology for the nutritional development of wheat.
Salinity is a critical agricultural threat that reduces the productivity of several crops. Tomato (Solanum lycopersicum) is the world’s second most significant horticultural commodity, which struggles due to salt concentrations in irrigation water, even in hydroponic systems. This research evaluated seed priming treatments (hydro-, halo-, bacterio-, and halo-bacteriopriming) at different phenological stages under two salinity conditions (0 and 16 mM NaCl) to improve crop production. After evaluating physiological variables and multivariate statistical analyses, this study’s main breakthroughs are: Priming treatments modified the physiological, nutritional, and productive metabolism of tomato plants. Bacterio- and halo-bacteriopriming using an endophytic and halophytic bacterial consortium reduced germination time, enhancing uniformity and synchronizing seedling emergence. Bacteriopriming enhanced N, P, Ca and Zn absorption in seedlings. In the vegetative and reproductive stages, bacteriopriming consistently increased concentrations of K, Mg, and Zn in leaves and fruits but depleted Na uptake. Improving the nutritional balance resulted in not only a higher concentration of chlorophyll but also an increase in the yield and beta-carotene concentration in tomato fruits. The results demonstrated that halo-bacteriopriming may be a biotechnological strategy for mitigating saline stress, optimizing tomato growth and nutraceutical quality, because it outperformed the plant response in all stages of development compared to the control and hydro- and haloprimed treatments.
Salinity represents a critical agricultural threat that reduces the productivity of several crops. Tomato (Solanum lycopersicum), recognized as the world´s second most significant horticultural commodity globally, is salt-sensitive. This research evaluated seed priming treatments (hydro, halo, bacterio, and halo-bacterio) at different phenological stages under two salinity conditions (0 and 16 mM NaCl) as a biotechnological alternative to mitigate salt stress and increase production. Using physiological variables and multivariate statistical analyses, this research demonstrated that priming treatments modified the physiological, nutritional, and productive metabolism of tomato plants. Bacteriopriming, using an endophytic and halophytic bacterial consortium isolated from halophytes, enhanced germination variables and N, P, Ca and Zn absorption in seedlings. In the vegetative and reproductive stage and under stress, halo-bacteriopriming consistently enhanced concentrations of K, Mg, and Zn in leaves and fruits, but decreased Na absorption. This nutritional balance allowed not only a higher concentration of chlorophyll but also a significant increase in yield and beta-carotene concentration in tomato fruits. For the first time, this research demonstrated that the halo-bacteriopriming with this kind of bacteria is a biotechnological strategy to mitigate saline stress, optimizing not only tomato growth, but also its nutraceutical quality. It significantly outperformed the plant response in all stages of development compared to those from control, hydro, and halo-primed treatments.