Effect of O,O-diethyl-1-(3,4-dimethoxyphenyl)-(1-ethynylcyclohexylaminomethyl)phosphonate on growth, and yield of vegetable cropsAbstract
This study investigates the effect of O,O-diethyl-1-(3,4-dimethoxyphenyl)-(1-ethynylcyclohexylaminomethyl)phosphonate (BA-3) on seed germination, plant growth, and yield of agricultural crops, including carrot, beetroot, and potato. The results indicate that seed germination increased by 14.0% and 27.0% at BA-3 concentrations of 0.002% and 0.0002%, respectively, compared to the control. Laboratory experiments demonstrated that treatment with BA-3 (0.0002% solution) enhanced germination energy by 16.0% and 22.0%, respectively. The reference standard HAU (0.06%) improved germination energy by 13.0% and overall germination by 12.0%. In addition, treatment of potato tubers with BA-3 resulted in a significant increase in the number of awakened buds, by 43.0% at 0.002% and 53.0% at 0.0002%, relative to the control. Field trials showed that the application of BA-3 at a concentration of 0.002% increased carrot yield by 4.0 t/ha (18.2%), while at 0.0002% the increase reached 4.8 t/ha (21.8%). For beetroot, treatment with BA-3 at 0.0002% led to a yield increase of 5.8 t/ha (22.3%) compared to the control. Similarly, potato yield increased by 3.6 t/ha (15.9%) at 0.002% and by 6.8 t/ha (30.0%) at 0.0002%. Overall, the obtained results demonstrate that BA-3 effectively stimulates plant growth and development, leading to improved productivity and enhanced agronomic performance of the studied crops.
Keywords:
plant growth regulator; potato; carrot; beetroot; crop yield
Resumo
Este estudo investiga os efeitos do O,O-dietil-1-(3,4-dimetoxifenil)-(1-etinilciclohexilaminometil)fosfonato (BA-3) na germinação de sementes, no crescimento das plantas e na produtividade de culturas agrícolas, incluindo cenoura, beterraba e batata. Os resultados demonstraram que a germinação das sementes aumentou em 14,0% e 27,0% nas concentrações de BA-3 de 0,002% e 0,0002%, respectivamente, em comparação com o controle. Os experimentos laboratoriais mostraram que o tratamento com BA-3 (solução a 0,0002%) aumentou a energia germinativa em 16,0% e 22,0%, respectivamente. O tratamento de referência com HAU (0,06%) promoveu um aumento de 13,0% na energia germinativa e de 12,0% na germinação total. Além disso, o tratamento dos tubérculos de batata com BA-3 resultou em um aumento significativo no número de gemas brotadas, de 43,0% na concentração de 0,002% e de 53,0% na concentração de 0,0002%, em relação ao controle. Os ensaios de campo mostraram que a aplicação de BA-3 na concentração de 0,002% aumentou a produtividade da cenoura em 4,0 t/ha (18,2%), enquanto a concentração de 0,0002% proporcionou um aumento de 4,8 t/ha (21,8%). Para a beterraba, o tratamento com BA-3 a 0,0002% resultou em um aumento de produtividade de 5,8 t/ha (22,3%) em comparação com o controle. Da mesma forma, a produtividade da batata aumentou em 3,6 t/ha (15,9%) na concentração de 0,002% e em 6,8 t/ha (30,0%) na concentração de 0,0002%. De modo geral, os resultados demonstram que o BA-3 estimula efetivamente o crescimento e o desenvolvimento das plantas, resultando em maior produtividade e melhor desempenho agronômico das culturas estudadas.
Palavras-chave:
regulador de crescimento vegetal; batata; cenoura; beterraba; produtividade da cultura
1. Introduction
Plant growth regulators (PGRs) are organic compounds of natural or synthetic origin that exhibit phytohormone-like activity and are capable of selectively influencing plant growth, development, and metabolism (Melati et al., 2024; Rademacher, 2015). They play a key role in regulating physiological processes, including seed germination, root system development, the growth of vegetative organs, and fruit development. The use of plant growth regulators helps increase crop yields, improve the quality of agricultural products, and enhance plants’ resistance to adverse environmental factors (Bhatla, 2018; Bhatla and Lal, 2023; Yan et al., 2026).
In intensive agricultural production, including the cultivation of medicinal and food crops, plant growth regulators (PGRs) are widely used due to their high efficacy and affordability. They are used to stimulate root formation, regulate vegetative growth, enhance the uniformity of plant development, and improve the marketability of the crop. Among the most common regulators are auxins, gibberellins, cytokinins, abscisic acid, as well as salicylic acid and ethylene (Ahmed et al., 2021; Kreslavski et al., 2023; Razzaq and Zhou, 2025).
Recent studies show that RPPs can mitigate the negative effects of abiotic stresses by regulating physiological and biochemical processes at various stages of plant development. In particular, they enhance stress tolerance, activate antioxidant defense systems, and reduce the toxic effects of pesticides (Wu et al., 2024).
Plant growth regulators are used in low concentrations and, unlike traditional fertilizers, contain fewer impurities (Gupta and Van Staden, 2021). As a result, their use is associated with a relatively low risk of toxic effects on humans and the environment (Kisvarga et al., 2022). PPPs have significant commercial potential and play a vital role in increasing global agricultural production by helping to mitigate the negative effects of environmental stresses and boost crop yields. In modern agricultural technologies, their use has become an integral part of sustainable agriculture. It is noted that the use of PPPs allows for an annual increase in global crop production of 10–15 million tons (Rademacher, 2015; Suman et al., 2017).
In addition, the use of plant growth regulators (PGRs) helps reduce the excessive use of fertilizers and pesticides, which has a positive impact on the environment. The current development of the agricultural sector requires the implementation of innovative approaches aimed at intensifying production and improving the quality of agricultural products while simultaneously reducing the environmental impact (Akimbayeva et al., 2025; Baitasheva et al., 2024; Shah et al., 2023; Zhumanova et al., 2024).
Indole-3-acetic acid (IAA) is a heterocyclic monocarboxylic compound and the primary natural auxin. Its structure was determined in 1934, after which a significant number of indole derivatives were synthesized, and their auxin activity was investigated (Etesami and Glick, 2024, p. 1995; George et al., 2007; Lavy and Estelle, 2016.; Woodward, 2005).
Extrasol is a microbiological product used in agriculture that exhibits both growth-promoting and protective effects. It is one of the recent developments of the All-Russian Research Institute of Agricultural Microbiology and received state registration as a microbiological fertilizer in 1999. The product successfully combines the best qualities of biological and chemical agents. Its active ingredient is a strain of rhizosphere bacteria Bacillus subtilis Ch-13, isolated from the root zone of healthy plants (Buldakov and Plekhanova, 2020; Chebotar et al., 2000; Naliukhin et al., 2018).
A comparison with other compounds in this class, including amido phosphates (Hong-wu et al., 2002; Kuandykova et al., 2025), alkyl phosphonates (Nadiveedhi et al., 2021), phosphorus-containing growth regulators (Zhang et al., 2023) and phosphonic acid esters (Zhang et al., 2024), suggests that the specific structural features of compound BA-3 may be the determining factor behind its enhanced biological activity.
2. Materials and Methods
2.1. The laboratory experiment
The optimal growth-activating concentrations of the new compound were determined in the laboratory conditions: the effect of the preparation on the germination energy and viability of carrot and beetroot seeds and on the awakening of potato tuber buds. The concentration of the preparation varied from 2.0 up to 0.0002%. The optimal active concentrations of the preparation were further studied on the growth, development and yield of crops in the field conditions.
Carrot and seeds were soaked in freshly prepared solutions of the BA-3. Carrot and beet seeds soaked in water served as a control; a 0.06% solution of HAU (heteroauxin) was used as a standard. The seeds were germinated in Petri dishes in a thermostat, there were six replicates (repetitions). The sprouted seeds of carrots and were counted in 2 periods: the first - 5 days after the treatment (to determine the germination energy), the second - after 10 days (to determine the seed germination). The effect of the preparation on bud awakening was studied on the potato tubers. For potatoes, seeds soaked in the Extrasol solution (10.0%) served as a standard. The potato tubers were sprouted in boxes in wet sawdust, 20 tubers were sprouted in each repetition, the repetition was sixfold. The awakened buds were counted after 10 and 15 days (Miedema, 1973).
2.2. The field experiment
The established optimal concentrations of the preparation were further studied in the field for their effect on the growth, development and yield of crops. To conduct the study in the field, the seeds were treated with freshly prepared solutions of the BA-3; untreated seeds served as a control, while seeds treated with the HAU solution (0.06%) served as a standard in the experiments with carrot, beetroot and the trubers soaked in a 10.0% Extrasol solution served as a standard in the experiments with potato.
The achieved technical outcome included an increase in the yield of agricultural crops (carrot, beetroot and potato), promotion of their subsequent growth and development, as well as a marked decrease in both crop loss and toxicity. Throughout the growing season, biometric assessments were performed on 20 typical plants, focusing on parameters such as plant height, leaf number, and fruit weight. Field productivity was evaluated separately for each experimental plot. Statistical analysis of the efficiency indicators was conducted using the analysis of variance method, following the methodology proposed by B. A. Dospekhov (Dospehov, 1985). Modifications in plant morphology were observed as a result of seed treatment (Nurmahanova et al., 2024; Starič et al., 2020). Census plots for carrot and beetroot, each measuring 10 m2, for potatoes 25 m2 were established in four replications (Figure 1). In the experiments, the phenological observations were carried out for each variant, taking into account the sowing date, single and mass shoots, the beginning of the formation of 2-3 and 6-8 leaves (Alexander, 2020; Bierhuizen, 1981; Dzhiembaev, 2022; National Potato Council of Kenya, 2019). Work has been carried out to control the influence of a chemical substance that affects the growth and development of plants on the activity of using carrot and beetroot as growth accelerators in the agro-industrial complex. 0,0-diethyl-1-(3,4-dimethoxyphenyl)-(1-ethynylcyclohexylaminomethyl)phospho-nate with the code BA-3 and the following formula was proposed as a growth stimulator for carrot and beetroot seeds for the technical result.
2.3. Synthesis, structure and determination of the BA-3 preparation
The chemical structures of the active compound BA-3 were determined by the nuclear magnetic resonance (NMR) analysis. 1H NMR spectra were obtained in Chloroform-d, using a Bruker MSL 400 spectrometer (Bruker Corporation, Germany) at 400 MHz for the 1H NMR spectra, using Chloroform-d as an internal standard. The IR spectra were recorded using a UR-20 spectrometer in the range of 400-3600 cm-1 in KBr. The melting points were determined in glass capillaries using a Stuart SMP 10 instrument. The elemental analysis was performed on a Carlo Erba EA 1108 apparatus.
0,0-diethyl-1-(3,4-dimethoxyphenyl)-(1-ethynylcyclohexylaminomethyl)phosphonate (4). To a mixture of 0.24 g (2.10 mmol) of diethyl phosphite (3) in 50 ml of benzene, 0.20 g (2.10 mmol) of 1-ethynyl-1-aminocyclohexane (1), 0.30 g (2.10 mmol) of 3,4-dimethoxybenzaldehyde (2), and 0.04 g (0.21 mmol) of p-toluenesulfonic acid. The reaction mixture was boiled in a flask fitted with a Dean-Stark condenser and a reflux condenser for 8–30 h. The reaction mixture was extracted with a saturated aqueous solution of sodium bicarbonate (3 × 10 mL). The organic phase was distilled off, and the resulting products were purified by recrystallization (Figure 2).
The yield: 0.71 g (84%), white powder, m.p. 83-84°С. Rf 0,82 (benzene:acetone 10:1). The IR spectrum, ν, cm-1: 3256 (≡СН), 3225 (NH), 2102 (С≡С), 1260 (P=O), 1045,1060 (Р-О-С). 1H NMR (400 MHz, Chloroform-d) δ 1.28 s (6H, OCH3), 1.18 t (3H, 7.1 MHz, POCH2CH3), 1.31 s (3H, 7.1 MHz, POCH2CH3), 1.68–1.72 s (10H, cyclohex.), 2.38 s (1H, CH), 2.67 s (1H, J 21.9 Hz, NH), 3.86–3.96 s (4H, POCH2), 6.86-7.44 m (3H, CH). 31Р NMR, δ, (CDCl3, δР,): 20.18. Anal. Calc. for C21H32O5NP, %: C 75.18; H 7.64; N 3.21; P 7.38. Found., %: C 75.31; H 7.82; N 3.40; P 7.52 (Doszhanova et al., 2021).
3. Results
3.1. Effect of BA-3 on the germination energy and germination capacity of carrot and beetroot seeds and on awakening of the potato tuber buds
3.1.1. Study of the effect of the preparation on the germination energy and germination capacity of carrot and beetroot seeds
The results of the laboratory studies have shown that seed treatment with the preparation with the concentrations of 0.002 and 0.0002%, conventionally called BA-3, increases the germination energy of carrot seeds by 14.0 and 27.0%, compared to the control. Germination of carrot seeds when treated with BA-3 in the concentrations of 0.002 and 0.0002%, increases by 16.0 and 22.7%, compared to the control. The treatment of carrot seeds with the 0.06% solution of HAU (heteroauxin) increases the germination energy by 13.0% and seed germination by 12.0%, compared to the control. The data presented in Table 1 show that the treatment of beetroot seeds in the BA-3 solution of the concentration of 0.002%, increases the germination energy of seeds by 14.0%, germination by 15.0%, in the concentration of 0.0002% - by 19.0 and 18.0%, respectively. The HAU standard (0.06%) increases the germination energy by 9.0% and germination by 10.0%.
The effect of a new preparation on the germination energy and seed viability of carrots and beetroot.
3.1.2. Study of the effect of the preparation on the awakening of the potato tuber buds
The results of the laboratory studies have shown that the treatment of the tubers with BA-3 in the concentration of 0.002% increases the number of the awakened buds, compared to the control by 43.0%; the treatment of the tubers BA-3 in the concentration of 0.0002% increases the number of the awakened buds by 53.0%., compared to the control.
It should be noted that the increase in the number of the awakened buds occurs due to the awakening of the lateral and stem end parts of the tubers, which in the control variant (as usual) have remained unawakened. When potato tubers have been treated with the standard preparation Extrasol in the concentration of 10%, the number of the awakened buds has been by 17.0% higher than in the control (Table 2).
3.2. The effect of the BA-3 on the growth, development and yield of carrot
The effect of the BA-3 preparation during the pre-sowing treatment of carrot seeds on the growth, development and yield was tested in field conditions. The results of phenological observations show that in the experiments where carrot seeds have been soaked in the solutions of the 0.002% and 0.0002% concentrations of the BA-3 preparation, sprouted 2 and 5 days earlier, compared to the control. When treating seeds with the Extrasol standard, shoots have appeared 1 day earlier, compared to the control experiment. The phase of 2-4 and 6-8 true leaves when treated with the preparation in the concentration of 0.002% has occurred 2 days earlier; when treated in the concentration of 0.0002% - 5 days earlier (Table 3).
Intensity of the emergence of seedlings and the development phases of carrots under the effect of the treatment with BA-3 in the field conditions.
The pre-sowing seed treatment with the optimal concentrations increases the density of carrot plants. The data presented in Table 4 indicate that seed treatment with BA-3 in the concentration of 0.002% increases the density of plants by 17.1%, and in the concentration of 0.0002% - by 20.0%. Soaking in the HAU solution (0.06%) increases the density of plants by 7.1%.
It follows that the pre-sowing treatment of carrot seeds with BA-3 in the optimal concentration increases the density of standing, i.e. the field germination of carrot plants. The treatment of carrot seeds with the preparation in the optimal concentration has a significant effect on the growth and development of carrot plants: from the data presented in Table 5 it follows that the height of the plants grown from seeds treated with the preparation on the day of recording when using BA-3 has been higher, compared to the control on the 30th, 45th and 60th day by 2.8, 3.0 and 3.1 cm in the concentration of 0.002%; and in the concentration of 0.0002% - by 6.5, 7.0 and 5.8 cm, respectively. The use of the standard leads to an insignificant increase in the plant height. The number of leaves on one plant grown from the seeds, treated with BA-3 in the concentration of 0.002%, have increased, compared to the control on the 30th, 45th and 60th day by 1.2, 1.7 and 1.8 pcs; in the concentration of 0.0002% - by 1.9, 2.0 and 2.2 pcs, respectively. When treating the seeds with the standard in the concentration of 0.06%, the increase in the number of leaves has made up 0.4, 1.1 and 1.9 pcs, compared to the control.
Thus, the plants grown from the seeds, treated with the optimal concentration of the preparation, have grown and developed significantly better, which, in turn, has a positive effect on the increase in the mass of carrot roots (Figure 3). Thus, the increase in the mass of the roots on the 30th, 45th and 60th days of recording in the variant with the BA-3 preparation in the concentration of 0.002%, has been 14.0±0.17, 22.9±0.08 and 38.8±0.08 grams, and in the concentration of 0.0002% - 15.7±0.13, 25.8±0.04 and 39.8±0.04 grams. When using the HAU standard (0.06%), the increase in mass has been 10.5±0.02, 17.3±0.02, 30.1±0.02 grams, in the control variant - 9.0±0.16, 16.0±0.08 and 28.0±0.08 grams (Figure 3).
The data on the carrot root yield, presented in Table 6, indicate that the pre-sowing treatment of carrot seeds with BA-3 in the concentration of 0.002% increases the yield by 4.0±0.01 t/ha or 18.2±0.02%, compared to the control; and in the concentration of 0.0002% - by 4.8±0.02 t/ha or 21.8±0.03%. The treatment with the 0.06% solution of the GAU standard has led to an increase in yield by 1.2±0.02 t/ha or 5.5±0.01%, compared to the control.
3.3. The effect of the BA-3 on the growth, development and yield of beetroot
Phenological observations of the growth and development of beetroot plants have shown that the seeds, treated in the 0.002 and 0.0002% solutions have emerged 3 and 5 days earlier than the control (Table 7). The 2-4 and 6-8 leaf phases have also preceded the control variant: at 0.002% - by 3 days, at 0.0002% - by 5 days.
The effect of the new preparation on the emergence and development phases of beetroot plants.
The pre-sowing treatment of beetroot seeds increases the plant density. The data, presented in Table 8, indicate that the treatment of beet seeds with BA-3 in the concentration of 0.002% increases the plant density by 25.6%, and in the concentration of 0.0002% - by 32.5%. Soaking in the HAU solution (0.06%) increases the plant density by 13.8%.
The significant of treating beetroot seeds with the preparation solutions has persisted until the end of the growing season. This is evidenced by the results of the biometric measurements. Thus, the analysis of the data presented in Table 9 shows that the plants grown from the seeds treated with BA-3 in the concentrations of 0.002 and 0.0002% have been taller than the control plants (on the day of recording) by 3.5, 3.0, 5.0 cm and 6.0, 6.0, 6.5 cm; for the standard - by 2.0, 4.0 and 2.0 cm, respectively. The number of leaves on the 60th day after the emergence has been greater for BA-3 (0.002 and 0.0002%) by 1.7-4.6 pcs.; for the standard - by 2.7 pcs.
Changes in the growth and development of the beetroot plants after the seed treatment with the new preparation BA-3.
The weight of the roots from the seeds treated with the BA-3 on the 30th, 45th and 60th days of recording has been greater than the control for the concentrations of 0.002 and 0.0002% by 1.6, 3.2, 11.0 and by 4.4, 7.0, 14.4 grams, respectively (Figure 4).
Dynamics of the increase in the weight of the beetroot roots from the seeds, treated with the new preparation.
The BA-3 preparation has activated the growth and development of the beetroot plants when treating the seeds, which in turn has led to an increase in the yield of the root crops. Thus, the maximum increase to the control was obtained when treating seeds with BA-3 at a concentration of 0.0002% and amounted to 5.8±0,02 t/ha or 22.3% (Table 10).
The effect of the new BA-3 preparation on the yield of the beetroot crops of the "Kyzyl kuren" variety.
3.4. The effect of BA-3 on the growth, development and yield of potatoes
Phenological observations have shown that in the variants where the tubers have been treated with BA-3 in the concentration of 0.0002% before planting, the shoots have emerged 4 days earlier than the control; when treated with Extrasol (10%), the shoots have emerged 1 day earlier than in the control variant (Table 11). Thus, the preparation, stimulating the germination of the potato tubers, has accelerated the emergence of shoots 3-4 days earlier.
The effect of the new preparation on the germination, growth and development of the potato plants.
The plants grown from the treated tubers have grown and developed better, and have been noted for having a larger mass of potato foliage. Thus, from Figure 5 it is evident that the mass of tops in the variant where the tubers have been treated with BA-3 before planting, from the beginning of the growing season has exceeded the mass of tops in the control variant: under the effect of the preparation in the concentration of 0.0002%, the mass of tops has been 123.0 g more than in the control variant at the first count, and 140 g more at the second count; in the Extrasol standard (10%) – by 17 and 30 g. The acceleration of the growth of the mass of the above-ground part of plants has been observed until the end of the growing season.
Effect of BA-3 on biomass accumulation in above-ground organs of potato seedlings at 45 (a) and 60 (b) days after germination.
The yield formation depends not only on the assimilation surface of the potato plants, but also on the formed number of the tubers. As can be seen from Table 12, the studied treatments has had a positive effect on the tuberization process. Thus, at the first determination date (on the 45th day after the emergence), 6.1±0.02 tubers per bush have been in the control variant, and 7.6±0.05 tubers per bush have been in the variant with the BA-3 preparation in the concentration of 0.002%; in the concentration of 0.0002% - 8.7±0.01 tubers, and 6.5±0.01 tubers - in the variant with the standard.
At the second determination date (on the 60th day after the emergence), 7.0±0.02 tubers per bush have been in the control, and 9.4±0.02 tubers per bush have been in the variant with the BA-3 preparation in the concentration of 0.002%, and 11.4±0.01 pieces of tubers in the concentration of 0.0002%, respectively; 8.3±0.01 pieces of tubers - in the variant with the standard.
The active growth and development of potatoes has had a positive effect on the process of tuberization, which ultimately has led to an increase in the potato yields (Table 13). The data in the Table show that the treatment of the tubers with BA-3 in the concentration of 0.002% increases the potato yield by 3.6±0.01 t/ha or 15.9±0.03%, compared with the control variant; and in the concentration of 0.0002% – by 6.8±0.01 t/ha or 30.0±0.02%. The treatment of the tubers with the Extrasol standard preparation (10.0%) increases the potato yield by 2.3±0.02 t/ha or 10.1±0.02% (Dzhiembaev, 2022).
The effect of the pre-treatment of the seeds with the new preparation on the yield of potatoes of the “Aksor” variety.
4. Discussion
The results of the present study demonstrate that 0,0-diethyl-1-(3,4-dimethoxyphenyl)-(1-ethynylcyclohexylaminomethyl)phosphonate (BA-3) exhibits pronounced plant growth-promoting activity under both laboratory and field conditions. Pre-sowing treatment with BA-3 at low concentrations (0.002 and 0.0002%) positively affected seed germination, early plant growth and development, potato bud awakening, and final crop yield. Among the concentrations tested, 0.0002% generally produced the most pronounced biological response. At this concentration, BA-3 increased carrot seed germination energy and germination by 27.0 and 22.7%, respectively, whereas the corresponding increases for beetroot were 19.0 and 18.0%. Treatment of potato tubers with 0.0002% BA-3 increased the number of awakened buds by 53.0% relative to the control. These laboratory responses were consistent with the field experiments, in which BA-3 at 0.0002% increased the yields of carrot, beetroot, and potato by 4.8 t/ha (21.8%), 5.8 t/ha (22.3%), and 6.8 t/ha (30.0%), respectively.
Plant growth regulators comprise chemically and functionally diverse compounds capable of modifying plant developmental and physiological processes. Their effects may include changes in seed germination, dormancy, shoot development, flowering, fruit formation, and senescence, depending on the chemical nature of the regulator and the physiological state of the plant (Rademacher, 2015). In this context, the pronounced activity of BA-3 is particularly interesting because the compound belongs to the structurally diverse class of organophosphorus compounds containing an α-aminophosphonate framework (Fahad et al., 2016; Shah et al., 2021).
α-Aminophosphonates are structural analogues of α-amino acids and constitute an important class of biologically active organophosphorus compounds. Previous studies have demonstrated that selected α-aminophosphonate derivatives can significantly influence plant growth and development. (Nadiveedhi et al., 2021) synthesized a series of α-furfuryl-2-alkylaminophosphonates and demonstrated their plant growth-regulatory activity. Importantly, their effects on root and shoot development varied according to molecular structure, indicating that the biological response of plants to α-aminophosphonates is strongly structure-dependent. These findings provide relevant evidence that modification of the α-aminophosphonate scaffold can generate compounds with distinct plant growth-regulating properties.
More recent findings further support the biological potential of this class of compounds. Synthesized a novel pyridine-containing aminophosphonate, dimethyl((3-phenoxyphenyl)((pyridin-2-ylmethyl)amino)methyl)phosphonate (PMAAPh), using the Kabachnik-Fields reaction (Ten et al., 2026). Its water-soluble succinate form, PMAAPh-Suc, was shown experimentally to stimulate wheat seed germination and vigor. Thus, the results of (Ten et al., 2026) provide recent independent evidence that structurally diverse aminophosphonate derivatives can exhibit plant growth-promoting properties. The stimulatory effects observed for BA-3 in the present study are therefore consistent with the emerging evidence for plant growth-regulatory activity within this class of organophosphorus compounds. Nevertheless, the substantial structural differences between BA-3 and PMAAPh indicate that their biological effects cannot be directly extrapolated and may arise from different structure-dependent interactions with plant physiological processes.
At the same time, the biological effects of α-aminophosphonates should not be generalized as exclusively growth-promoting. Previous investigations have demonstrated that structurally related aminophosphonates may also exhibit phytotoxic and growth-inhibitory effects depending on their molecular structure, concentration, and the plant species tested (Lewkowski et al., 2017; Matusiak et al., 2013). For example, furan-derived aminophosphonic acids were reported to exert phytotoxic effects on radish (Raphanus sativus) and oat (Avena sativa), whereas studies of thiophene-derived aminophosphonates demonstrated considerable differences in their effects on plant growth among individual derivatives. These observations indicate that relatively small structural modifications within aminophosphonate molecules may markedly alter their biological properties.
This structure–activity relationship is particularly relevant to the interpretation of BA-3 activity. BA-3 combines an α-aminophosphonate framework with a 3,4-dimethoxyphenyl moiety and an ethynyl-containing cyclohexyl fragment. Previous studies of aminophosphonate derivatives have shown that both the nature and position of aromatic substituents can influence their effects on plants. Rogacz et al. (2019), for example, demonstrated different phytotoxicity profiles for methylphenyl- and methoxyphenyl-substituted aminophosphonates and further showed that the ortho-, meta-, or para-position of the aromatic substituent affected plant responses. Methoxyphenyl-containing derivatives were generally less phytotoxic than the corresponding methylphenyl analogues in the investigated systems.
From this perspective, the two methoxy groups of the 3,4-dimethoxyphenyl moiety in BA-3 may contribute to its physicochemical and biological properties by modifying the electronic and lipophilic characteristics of the aromatic fragment. In addition, the phosphonate, amino, aromatic, ethynyl, and cyclohexyl structural elements may collectively determine the interaction of BA-3 with plant physiological processes. However, because the present study did not investigate a series of structurally related BA-3 analogues, a definitive structure–activity relationship cannot yet be established. The proposed contribution of individual structural fragments should therefore be considered a working hypothesis requiring further experimental validation.
An important finding of the present study is the non-linear relationship between BA-3 concentration and biological response. Although both concentrations tested showed growth-promoting effects, the lower concentration of 0.0002% was generally more effective than 0.002%. In carrot, BA-3 increased yield by 4.8 t/ha (21.8%) at 0.0002%, compared with 4.0 t/ha (18.2%) at 0.002%. An even more pronounced difference was observed for potato, where the yield increase reached 6.8 t/ha (30.0%) at 0.0002%, compared with 3.6 t/ha (15.9%) at 0.002%. A similar trend was observed in the laboratory experiments: treatment of potato tubers increased the number of awakened buds by 43.0% at 0.002% and by 53.0% at 0.0002%.
These findings demonstrate that the biological effect of BA-3 is not directly proportional to its applied concentration and suggest the existence of an optimal low-dose range. Previous studies of aminophosphonate derivatives have likewise demonstrated concentration-dependent differences in plant responses, including changes in seedling emergence, root elongation, shoot development, and biomass (Lewkowski et al., 2017; Rogacz et al., 2019). Therefore, the greater efficacy of BA-3 at 0.0002% may reflect an optimal concentration at which growth-promoting responses are maximized, whereas increasing the concentration does not necessarily result in a proportional enhancement of biological activity. However, since only a limited number of BA-3 concentrations were evaluated in the present study, further experiments covering a broader concentration range are required to establish a complete dose–response relationship and determine the precise optimal concentration.
Comparison with the reference preparations further supports the potential of BA-3 as a plant growth-promoting compound. In carrot, treatment with BA-3 at 0.0002% increased yield by 4.8 t/ha (21.8%), whereas HAU (heteroauxin) at 0.06% increased yield by only 1.2 t/ha (5.5%). The laboratory experiments also showed that HAU increased beetroot seed germination energy and germination by 9.0 and 10.0%, respectively, whereas BA-3 at 0.0002% produced increases of 19.0 and 18.0%. Similarly, BA-3 at 0.0002% increased potato yield by 6.8 t/ha (30.0%), whereas treatment with Extrasol resulted in an increase of 2.3 t/ha (10.1%). Thus, under the experimental conditions of the present study, BA-3 produced a greater growth- and yield-promoting response than the reference treatments.
Nevertheless, these comparisons should be interpreted cautiously. BA-3, HAU, and Extrasol differ substantially in chemical composition, formulation, and potentially in their mechanisms of action. Therefore, the differences in their nominal application concentrations cannot be interpreted directly as differences in intrinsic biological potency. Rather, the present results demonstrate that BA-3 produces a pronounced biological response at a low applied concentration under the experimental conditions evaluated in this study.
The field observations further support the effects of BA-3 on early crop establishment and subsequent development. At the optimal concentration of 0.0002%, seedlings emerged approximately 2–4 days earlier, and the field establishment of carrot plants increased by 20.0%. Pre-sowing treatment with BA-3 also improved plant stand density and positively influenced potato tuber formation. At 45 days after emergence, plants treated with 0.0002% BA-3 formed an average of 8.7 tubers per plant, increasing to 11.4 tubers per plant at 60 days. Collectively, these findings indicate that the effects of BA-3 are not restricted to a single developmental stage but are associated with improved early establishment and subsequent crop productivity.
The physiological and molecular mechanisms underlying these effects remain to be elucidated. Although modulation of nutrient uptake, enzyme activity, antioxidant responses, phytohormone signaling, photosynthetic processes, or tolerance to environmental stress could potentially contribute to the observed growth-promoting effects, these parameters were not directly measured in the present study. Therefore, such mechanisms should currently be considered hypotheses rather than established explanations for BA-3 activity. Future investigations should include measurements of endogenous phytohormone levels, photosynthetic parameters, nutrient status, antioxidant enzyme activities, and oxidative stress markers to clarify the physiological and molecular basis of BA-3 action.
Overall, the combined laboratory and field results demonstrate the potential of BA-3 as a plant growth-promoting compound, with 0.0002% being the most effective concentration among those tested. The observed activity is consistent with previous and recent reports demonstrating that appropriately substituted α-aminophosphonate derivatives can significantly influence plant development (Nadiveedhi et al., 2021; Ten et al., 2026). Nevertheless, before BA-3 can be recommended for practical agricultural application, further studies are required to establish a comprehensive dose-response relationship, evaluate its efficacy across a broader range of crops and agroclimatic conditions, investigate its effects on crop quality and soil microbial communities, and assess its environmental fate and safety.
Data Availability Statement
Research data is available in the body of the article.
References
-
AHMED, T., NOMAN, M., MANZOOR, N., SHAHID, M., ABDULLAH, M., ALI, L., WANG, G., HASHEM, A., AL-ARJANI, A.B.F., ALQARAWI, A.A., ABD ALLAH, E.F. and LI, B., 2021. Nanoparticle-based amelioration of drought stress and cadmium toxicity in rice via triggering the stress responsive genetic mechanisms and nutrient acquisition. Ecotoxicology and Environmental Safety, vol. 209, pp. 111829. https://doi.org/10.1016/j.ecoenv.2020.111829 PMid:33383335.
» https://doi.org/10.1016/j.ecoenv.2020.111829 -
AKIMBAYEVA, N., ZHUMANOVA, N., MYRZAKHMETOVA, N., DZHIEMBAEV, B., KUANDYKOVA, A., KUDAIBERGENOVA, G., DIYAROVA, B., YEREZHEPOVA, A. and KUDAIBERGENOVA, G., 2025. Synthesis of functionally substituted dithiocarbamate derivatives as potential plant growth regulators. ES Food and Agroforestry, vol. 21, no. 1623, pp. 1-11. https://doi.org/10.30919/faf1623
» https://doi.org/10.30919/faf1623 -
ALEXANDER, S., 2020 [viewed 1 July 2026]. A guide to vegetable growing[online]. Agriculture and Food Developmente Authority. Available from: https://teagasc.ie/wp-content/uploads/media/website/publications/2020/A-Guide-to-Vegetable-Growing---9th-Edition.pdf
» https://teagasc.ie/wp-content/uploads/media/website/publications/2020/A-Guide-to-Vegetable-Growing---9th-Edition.pdf -
BAITASHEVA, G., MUSSINA, A., MEDEUOVA, G., KUANDYKOVA, A., IMANOVA, E., SARTAYEVA, A., ZHAMANBAYEVA, K. and UMBETULLA, A., 2024. Dynamics of germination of vegetable seeds when using dimethyl (1-hydroxy-1-phenylethyl) phosphanate as an accelerator. Caspian Journal of Environmental Sciences, vol. 22, no. 4, pp. 889-897. https://doi.org/10.22124/CJES.2024.8138
» https://doi.org/10.22124/CJES.2024.8138 -
BHATLA, S.C., 2018. Plant growth regulators: an overview. In: S.C. BHATLA and M. A. LAL, eds. Plant physiology, development and metabolism Singapore: Springer Singapore. https://doi.org/10.1007/978-981-13-2023-1_14
» https://doi.org/10.1007/978-981-13-2023-1_14 -
BHATLA, S.C. and LAL, M.A., 2023. Plant physiology, development and metabolism Singapore: Springer Singapore. Plant growth regulators: an overview, pp. 391-398. https://doi.org/10.1007/978-981-99-5736-1_14
» https://doi.org/10.1007/978-981-99-5736-1_14 -
BIERHUIZEN, J.F., 1981. Vegetable growing handbook. Scientia Horticulturae, vol. 15, no. 2, pp. 197. https://doi.org/10.1016/0304-4238(81)90108-4
» https://doi.org/10.1016/0304-4238(81)90108-4 -
BULDAKOV, S.A. and PLEKHANOVA, L.P. 2020. Effective use of the biologic drug extrasol on seed potatoes. International Research Journal, vol. 4, no. 94, pp. 40-45. https://doi.org/10.23670/IRJ.2020.94.4.006
» https://doi.org/10.23670/IRJ.2020.94.4.006 - CHEBOTAR, V., KHOTYANOVICH, A., and CAZACOV, C., 2000. EXTRASOL - a new multifunctional biopreparation for ecologically safe agriculture. In: H. KLEEBERG and C.P. ZEBITZ, eds. Practice oriented results on use and production of neem ingredients and pheromones IX Hohenahr: Trifolio, pp. 127-134.
-
DOSPEHOV, B.A., 1985 [viewed 1 July 2026]. Methodology of field experience (with the basics of statistical processing of research results) [online]. Agropromizdat. Available from:https://arm.ssuv.uz/frontend/web/books/652527ba2ddf1.pdf
» https://arm.ssuv.uz/frontend/web/books/652527ba2ddf1.pdf -
DOSZHANOVA, K.A., KUANDYKOVA, A.B., DZHIEMBAEV, B.Z. and BURILOV, A.R., 2021. Synthesis of new α-aminophosphonates based on cyclohexylamines in the conditions of the fields kabachnik reaction. Chemical Journal of Kazakhstan, vol. 73, no. 1, pp. 126-133. https://doi.org/10.51580/2021-1/2710-1185.13
» https://doi.org/10.51580/2021-1/2710-1185.13 - DZHIEMBAEV, B.Z. Application of 0,0-diethyl-1- (3,4-dimethoxyphenyl)—(1-ethynylcyclohexylaminomethyl)phosphonate as a growth stimulator of vegetable crops Kazakhstan. Patent KZ nº 35532. 18-03-2022.
-
DZHIEMBAEV, B.Z., KUANDYKOVA, A.B., AKYLBEKOV, N.I., DOBRYNIN, A.B. and BURILOV, A.R., 2023. Synthesis of amidophosphates based on 1-ethynyl-1-aminocyclohexane upon microwave activation and their biological activity. Eurasian Chemico-Technological Journal, vol. 25, no. 1, pp. 57-64. https://doi.org/10.18321/ectj1495
» https://doi.org/10.18321/ectj1495 -
ETESAMI, H. and GLICK, B.R., 2024. Bacterial indole-3-acetic acid: A key regulator for plant growth, plant-microbe interactions, and agricultural adaptive resilience. Microbiological Research, vol. 281, no. 127602, pp. 127602. https://doi.org/10.1016/j.micres.2024.127602 PMid:38228017.
» https://doi.org/10.1016/j.micres.2024.127602 -
FAHAD, S., HUSSAIN, S., SAUD, S., HASSAN, S., IHSAN, Z., SHAH, A., WU, C., YOUSAF, M., NASIM, W., ALHARBY, H., ALGHABARI, F. and HUANG, J., 2016. Exogenously applied plant growth regulators enhance the morpho-physiological growth and yield of rice under high temperature. Frontiers in Plant Science, vol. 7, no. 1250, pp. 1250. https://doi.org/10.3389/fpls.2016.01250 PMid:27625658.
» https://doi.org/10.3389/fpls.2016.01250 -
GEORGE, E.F., HALL, M.A. and KLERK, G.-J.D., 2007. Plant propagation by tissue culture 3rd ed. Dordrecht: Springer Dordrecht. Plant growth regulators i: introduction; auxins, their analogues and inhibitors, pp. 175-204. https://doi.org/10.1007/978-1-4020-5005-3_5
» https://doi.org/10.1007/978-1-4020-5005-3_5 - GUPTA, S. and VAN STADEN, J., 2021. Biostimulants for crops from seed germination to plant development: a practical approach New York: Academic Press, 458 p.
- HONG-WU, H., LI-PING, M., LI-MING, H. and ZHAO-JIE, L., 2002. Synthesis and plant growth regulating activity of 1-(1-phenyl-1,2,4-triazole-3-oxy acetoxy) alkyl phosphonates. Chinese Journal of Pesticide Science, vol. 4, no. 3, pp. 14-18.
-
KISVARGA, S., FARKAS, D., BORONKAY, G., NEMÉNYI, A. and ORLÓCI, L., 2022. Effects of biostimulants in horticulture, with emphasis on ornamental plant produc-tion. Agronomy (Basel), vol. 12, no. 5, pp. 1043. https://doi.org/10.3390/agronomy12051043
» https://doi.org/10.3390/agronomy12051043 -
KRESLAVSKI, V.D., SHMAREV, A.N., IVANOV, A.A., ZHARMUKHAMEDOV, S.K., STROKINA, V., KOSOBRYUKHOV, A., YU, M., ALLAKHVERDIEV, S.I. and SHABALA, S., 2023. Effects of iron oxide nanoparticles (Fe3O4) and salinity on growth, photosynthesis, antioxidant activity and distribution of mineral elements in wheat (Triticum aestivum). Functional Plant Biology : FPB, vol. 50, no. 11, pp. 932-940. https://doi.org/10.1071/FP23085 PMid:37573788.
» https://doi.org/10.1071/FP23085 -
KUANDYKOVA, A.B., DZHIEMBAEV, B.Z., DIYAROVA, B.M., AKIMBAYEVA, N.O. and ZHUMANOVA, N.A., 2025. Application of N-(1-ethynylcyclohexyl)amide of O,O-diethyl-phosphoric acid as a growth stimulant for vegetable crops. Brazilian Journal of Biology = Revista Brasileira de Biologia, vol. 85, pp. e295653. https://doi.org/10.1590/1519-6984.295653 PMid:41036878.
» https://doi.org/10.1590/1519-6984.295653 -
LAVY, M. and ESTELLE, M., 2016. Mechanisms of auxin signaling. Development (Cambridge, England), vol. 143, no. 18, pp. 3226-3229. https://doi.org/10.1242/dev.131870 PMid:27624827.
» https://doi.org/10.1242/dev.131870 -
LEWKOWSKI, J., KARPOWICZ, R., MORAWSKA, M., RYCHTER, P., ROGACZ, D., LEWICKA, K. and DOBRZYŃSKI, P., 2017. Synthesis and ecotoxicological impact of ferrocene-derived amino-phosphonates using a battery of bioassays. RSC Advances, vol. 7, no. 61, pp. 38399-38409. https://doi.org/10.1039/C7RA06079C
» https://doi.org/10.1039/C7RA06079C -
MATUSIAK, A., LEWKOWSKI, J., RYCHTER, P. and BICZAK, R., 2013. Phytotoxicity of New Furan-derived Aminophosphonic Acids, N -Aryl Furaldimines and 5-Nitrofuraldimine. Journal of Agricultural and Food Chemistry, vol. 61, no. 32, pp. 7673-7678. https://doi.org/10.1021/jf402401z PMid:23869973.
» https://doi.org/10.1021/jf402401z -
MELATI., MEILAWATI, N.L.W., RUSMIN, D., WAHYUNI, S. and DARWATI, I., 2024. The potential of natural plant growth regulators to increase vigor and growth of seeds clove. National Academy Science Letters, vol. 47, no. 4, pp. 355-359. https://doi.org/10.1007/s40009-023-01374-0
» https://doi.org/10.1007/s40009-023-01374-0 - MIEDEMA, A., 1973. A physiological study of adventitious bud formation in potato Groningen: University of Groningen, 66 p. Thesis of Plant Physiology and Genetic Improvement of Plants.
-
NADIVEEDHI, M.R., NUTHALAPATI, P., GUNDLURU, M., YANAMULA, M.R., KALLIMAKULA, S.V., PASUPULETI, V.R., AVULA, V.K.R., VALLELA, S., ZYRYANOV, G.V., BALAM, S.K. and CIRANDUR, S.R., 2021. Green synthesis, antioxidant, and plant growth regulatory activities of novel α-furfuryl-2-alkylaminophosphonates. ACS Omega, vol. 6, no. 4, pp. 2934-2948. https://doi.org/10.1021/acsomega.0c05302 PMid:33553912.
» https://doi.org/10.1021/acsomega.0c05302 - NALIUKHIN, A.N., GLINUSHKIN, A.P., KHAMITOVA, S.M. and AVDEEV, Y.M., 2018. The Influence of biomodified fertilizers on the productivity of crops and biological properties of soddy-podzolic soils. Entomology and Applied Science Letters, vol. 5, no. 3, pp. 1-7.
-
NURMAHANOVA, A., AKHMETOVA, A., ATABAYEVA, S., SADYROVA, G., CHILDIBAYEVA, A., KYRBASSOVA, E., IMANOVA, E., PARMANBEKOVA, M., CHUNETOVA, Z. and TYNYBEKOV, B., 2024. Study of morphogenesis and anatomical structure of arctium tomentosum mill. native to kazakhstan. Journal of Ecological Engineering, vol. 25, no. 8, pp. 325-335. https://doi.org/10.12911/22998993/190264
» https://doi.org/10.12911/22998993/190264 -
RADEMACHER, W., 2015. Plant growth regulators: backgrounds and uses in plant production. Journal of Plant Growth Regulation, vol. 34, no. 4, pp. 845-872. https://doi.org/10.1007/s00344-015-9541-6
» https://doi.org/10.1007/s00344-015-9541-6 -
RAZZAQ, S. and ZHOU, B., 2025. Revolutionizing crop production with iron nanoparticles for controlled release of plant growth regulators and abiotic stress resistance. Plant Nano Biology, vol. 13, pp. 100-172. https://doi.org/10.1016/j.plana.2025.100172
» https://doi.org/10.1016/j.plana.2025.100172 -
ROGACZ, D., LEWKOWSKI, J., SIEDLAREK, M., KARPOWICZ, R., KOWALCZYK, A. and RYCHTER, P., 2019. The effect of new thiophene-derived diphenyl aminophosphonates on growth of terrestrial plants. Materials (Basel), vol. 12, no. 12, pp. 2018. https://doi.org/10.3390/ma12122018 PMid:31238500.
» https://doi.org/10.3390/ma12122018 -
SHAH, S.H., ISLAM, S., ALAMRI, S., PARREY, Z.A., MOHAMMAD, F. and KALAJI, H.M., 2023. Plant growth regulators mediated changes in the growth, photosynthesis, nutrient acquisition and productivity of mustard. Agriculture, vol. 13, no. 3, pp. 570. https://doi.org/10.3390/agriculture13030570
» https://doi.org/10.3390/agriculture13030570 -
SHAH, S.H., ISLAM, S., PARREY, Z.A. and MOHAMMAD, F., 2021. Role of exogenously applied plant growth regulators in growth and development of edible oilseed crops under variable environmental conditions: a review. Journal of Soil Science and Plant Nutrition, vol. 21, no. 4, pp. 3284-3308. https://doi.org/10.1007/s42729-021-00606-w
» https://doi.org/10.1007/s42729-021-00606-w -
STARIČ, P., VOGEL-MIKUŠ, K., MOZETIČ, M. and JUNKAR, I., 2020. Effects of nonthermal plasma on morphology, genetics and physiology of seeds: a review. Plants, vol. 9, no. 12, pp. 1736. https://doi.org/10.3390/plants9121736 PMid:33316909.
» https://doi.org/10.3390/plants9121736 - SUMAN, M., SANGMA, P. and MEGHAWAL, D., 2017. Effect of plant growth regulators on fruit crops. Journal of Pharmacognosy and Phytochemistry, vol. 6, no. 2, pp. 331-337.
-
TEN, A.Y., SERDALY, D.T., SEILKHANOV, T.M. and YU, V.K., 2026. Lead-like properties of a novel pyridine aminophosphonate: synthesis, predictive evaluation and biological testing. Chemical Journal of Kazakhstan, vol. 1, no. 93, pp. 15-25. https://doi.org/10.51580/2026-1.2710-1185.02
» https://doi.org/10.51580/2026-1.2710-1185.02 -
NATIONAL POTATO COUNCIL OF KENYA, 2019 [viewed 1 July 2026]. Potato production handbook 2019 [online]. Northwest Potato Research Consortium. Available from: https://npck.org/Books/PotatoProductionHandbook2019(002).pdf
» https://npck.org/Books/PotatoProductionHandbook2019(002).pdf -
WOODWARD, A.W. and BARTEL, B., 2005. Auxin: regulation, action, and interaction. Annals of Botany, vol. 95, no. 5, pp. 707-735. https://doi.org/10.1093/aob/mci083 PMid:15749753.
» https://doi.org/10.1093/aob/mci083 -
WU, X., GONG, D., ZHAO, K., CHEN, D., DONG, Y., GAO, Y., WANG, Q. and HAO, G.-F., 2024. Research and development trends in plant growth regulators. Advanced Agrochem, vol. 3, no. 1, pp. 99-106. https://doi.org/10.1016/j.aac.2023.11.005
» https://doi.org/10.1016/j.aac.2023.11.005 -
YAN, Z., GUO, Y., XIANG, A., YANG, X., WU, S. and PANG, J., 2026. Facile preparation of amino-functionalized polyacrylonitrile/graphene oxide electrospun nanofibers for extraction of plant growth regulators in tomato. Journal of Chromatography. A, vol. 1777, pp. 466-948. https://doi.org/10.1016/j.chroma.2026.466948 PMid:41936774.
» https://doi.org/10.1016/j.chroma.2026.466948 -
ZHANG, S., ZHANG, M.-H., FENG, S., ZHANG, W.-J., ZHU, Y.-Y., LI, Z.-W. and BAI, S., 2024. Research progress in agricultural bioactive phosphonate esters compounds. Chemické Zvesti, vol. 78, no. 7, pp. 4045-4056. https://doi.org/10.1007/s11696-024-03356-y
» https://doi.org/10.1007/s11696-024-03356-y -
ZHANG, Z., HAN, T. and HE, H., 2023. Plant Growth and Phosphorus Uptake of Wheat in Response to Oxytetracycline. Journal of Soil Science and Plant Nutrition, vol. 23, no. 2, pp. 2162-2173. https://doi.org/10.1007/s42729-023-01170-1
» https://doi.org/10.1007/s42729-023-01170-1 -
ZHUMANOVA, N., AKIMBAYEVA, N., MYRZAKHMETOVA, N., DZHIEMBAEV, B., KUANDYKOVA, A., DIYAROVA, B., SEILKHANOV, O., KISHIBAYEV, K., MELDESHOV, A., SAPARBEKOVA, I. and YEREZHEPOVA, A., 2024. A comprehensive review of new generation plant growth regulators. ES Food and Agroforestry, vol. 17, no. 1190, pp. 1-19. https://doi.org/10.30919/esfaf1190
» https://doi.org/10.30919/esfaf1190
*
e-mail: bota.kuandyk1702@gmail.comEditor:
