Polymeric nanoparticles as an alternative for application of gibberellic acid in sustainable agriculture: a field study

Abstract

Nanocarrier systems for the encapsulation of agrochemicals can contribute to sustainable agriculture, but few nanosystems have been developed for plant growth regulators (PGRs). The present study evaluated the effects of seed priming using alginate/chitosan (nanoALG/CS) and chitosan/tripolyphosphate (nanoCS/TPP) containing GA₃ on the growth and productivity of Solanum lycopersicum cultivated under field conditions. The results demonstrated that nanocarrier systems could improve fruit production, with the productivity increasing almost 4-fold using nanoALG/CS-GA₃. This pioneering study demonstrates the potential of nanocarrier systems with PGRs for applications in agriculture.

Figure 1

Initial seedling growth 30 days after sowing: (a) shoot length (cm); (b) shoot dry weight (mg); (c) root length (cm); (d) root dry weight (mg). Seed treatments using the stock solution and dilutions of 1:10 and 1:100 (v/v), equivalent to concentrations of 0.05, 0.005, and 0.0005 mg/mL, respectively. Data shown as means and standard deviations (n = 12). Statistical analyses using one-way ANOVA with Tukey’s post-hoc test (significance level of p < 0.05), where α, β, and δ indicate significant differences relative to the control (water), treatment with GA₃, and treatment with nanoCS/TPP-GA₃, respectively.

Figure 2

Evaluation of plant development 120 days after sowing: (a) length of the aerial part (cm); (b) dry weight of the aerial part (g); (c) number of fruits per plant; (d) fruit fresh weight (g). Seed treatments using the stock solution and dilutions of 1:10 and 1:100 (v/v), equivalent to concentrations of 0.05, 0.005, and 0.0005 mg/mL, respectively. Data presented as means and standard deviations (n = 12). Statistical analyses using one-way ANOVA with Tukey’s post-hoc test (significance level of p < 0.05), where α, β, and δ indicate significant differences relative to the control (water), treatment with GA₃, and treatment with nanoCS/TPP-GA₃, respectively.

Figure 3

Estimation of plant production, considering the fresh fruit weight (ton) for an area of 10000 m² (1 ha). Seed treatments using the stock solution and dilutions of 1:10 and 1:100 (v/v), equivalent to concentrations of 0.05, 0.005, and 0.0005 mg/mL, respectively. Data presented as means and standard deviations (n = 12). Statistical analyses using one-way ANOVA with Tukey’s post-hoc test (significance level of p < 0.05), where α, β, and δ indicate significant differences relative to the control (water), treatment with GA₃, and treatment with nanoCS/TPP-GA₃, respectively.

Figure 4

Efficacies of the nanoALG/CS-GA₃ and nanoCS/TPP-GA₃ systems, relative to the use of GA₃, for the different parameters evaluated 120 days after sowing (a) length of the aerial part (b) dry weight of the aerial part (c) number of fruits (d) fruit weight. Seed treatments using the stock solution and dilutions of 1:10 and 1:100 (v/v), equivalent to concentrations of 0.05, 0.005, and 0.0005 mg/mL, respectively. Data presented as means and standard deviations (n = 12). Statistical analyses using one-way ANOVA with Tukey’s post-hoc test (significance level of p < 0.05), where α indicates significant difference relative to the treatment with nanoCS/TPP-GA₃.