High-Dynamized Dilutions in Disease Management, Development, and Yield of Common Beans (Phaseolus vulgaris L.)

Abstract

The active ingredients used in the phytosanitary management of bean crops have a residual power which results in contamination of the entire production chain. This study aimed to evaluate the effect of Calcarea carbonica, Calcarea phosphorica, Hepar Sulphur, and shell limestone on disease management and the development of bean plants. The experiments were carried out at Experimental Station of Epagri, Lages, SC, Brazil, and conducted in a randomized block design with six replications and two cultivars in three growing cycles. Distilled water and an untreated plot were the controls. Treatments were applied by spraying in three phenological stages. Following the appearance of initial symptoms, the incidence and severity of anthracnose, powdery mildew, and angular spot were assessed. At harvest, plant weight, thousand grain weight, number of pods per plant, and number of grains per pod were assessed. The data analysis of variance and Tukey’s test at 5% using the R software. The high-dynamized dilutions of Calcarea phosphorica in the first, shell limestone in the second and Hepar sulphur in the third cycle, increased grains/plant in Perola. By contrast, was an increase in the number of grains in Campeiro when Hepar sulphur, shell limestone and distilled water were applied in the first, second and third cycles, respectively. The application of Calcarea carbonica and Calcarea phosphorica reduced the severity of anthracnose, angular spot and powdery mildew. It can be concluded that high-dynamized dilutions have the potential to reduce the intensity of diseases in bean plants as well as increase grain production.

Keywords:
alternative control; fungus; beans production.

HIGHLIGHTS

Calcarea carbonica and Calcarea phosphorica decrease the diseases severity regardless the cultivar.

Calcarea phosphorica increase the number of grains per plant in cv. Perola.

Hepar sulphur increase the number of grains per plant in cv. Campeiro.

INTRODUCTION

Brazil is the world’s third largest bean producer (2,906,508 tons) and the main consumer (2,840,000 tons) [¹]. Despite the recognized social and economic importance of beans, the average yield in Brazil is much lower (1,199 kg ha-1) than the productive potential of the cultivars, due to interference, mainly of biotic origin [¹]. According to Wendland and coauthors [²], the occurrence of anthracnose (Colletotrichum lindemuthianum), angular spot (Pseudocercospora griseola), and powdery mildew (Erysiphe polygoni) diseases greatly affects the productive potential of commercial bean cultivars.

Chemical control, in a scheduled scheme using synthetic chemical fungicides, has been adopted as the standard procedure for disease management [³]. This procedure has facilitated the higher number of application of fungicides, increased bean production costs, and resulted in side effects to the environment. This, directly lead to the reduction of biodiversity and the natural resources of soil and water, thus drastically interfering with ecological services [⁴]. A study carried out by Pignati and coauthors [⁵] with the aim of quantifying the use of pesticides for bean crops showed that an average 5 L of pesticide was used per hectare of bean crop area, which means 15,650,180 liters of pesticide/year in total Brazilian production.

In addition to dangerous effects to the environment, the intensive use of fungicides induces pathogen resistance, because of selection pressure, which eliminates susceptible individuals and increases the population of fungicide-resistant individuals [⁶]. The first report of Colletotrichum lindemuthianum resistance was recorded by Meyer [⁷], who reported the pathogen’s low sensitivity to fungicides from the benzimidazole group. This result was again reinforced by Maringoni and Barros [⁸] and Sartori and Maringoni [⁹], who also reported low sensitivity of the pathogen to the fungicide.

New methods and strategies of pest management that have a low environmental impact and maintain the productive potential of commercial varieties are essential to develop sustainable cultivation systems that are highly acceptable to the public [¹⁰]. The use of natural substances, such as high-dynamized dilutions, as a substitute for pesticides are among the phytosanitary management measures with minimal negative impact on the agricultural ecosystems [¹¹]. Toledo and coauthors [¹²] reported that high-dynamized dilution of Ferrum sulphuricum at 6, 12 and 30 CH (CH=centesimal Hahnemannian dilution order) could reduce 49% occurrence of Alternaria solani in tomato fruits (Solanum lycopersicum). Oliveira and coauthor [¹³] showed that Ammonium carbonicum at 30 CH reduced by 18.29% the severity of the rust disease (Puccinia malvacearum) in mint (Mentha arvensis). Bonato and coauthors [¹⁴], when using Sulphur and Arsenicum album at 6, 12, 24 and 30 CH on mint plants, reported increased plant growth and essential oil content. Faedo and coauthors [¹⁵], when using Silicea terra in potencies 12 and 18 CH on strawberry plants (Fragaria x ananassa), found that plants treated with Silicea terra 12 CH had a larger leaf area, produced more leaves during the cycle, and had a greater root weight.

Encouraged by the findings reported above, the aim of this work was to evaluate the effect of high-dynamized preparations on the management of diseases of bean plants, as well as on plant development and grain production.

MATERIAL AND METHODS

Experimental design and choice of treatments

Experiments were carried out in a greenhouse with the support of the Homeopathy and Plant Health Laboratory at Epagri Experimental Station in Lages/SC, in three growing cycles, with two bean cultivars, Perola and Campeiro, from February 2021 to June 2023 (Figure 1). The experiments were conducted in randomized block design, with six repetitions. The treatments consisted of high-dynamized dilutions of Calcarea carbonica, Calcarea phosphorica, Hepar sulphur, and shell limestone biotherapic, all at a dynamization of 12 CH (CH= Hahnemannian centesimal dilution order). The preparations were chosen because their raw material contained the constituent calcium. Non-dynamized water and a plot without intervention were used as control plots. The experimental unit consisted of a pot containing two bean plants.

Figure 1
Schematic representation of the methodology used in the work

Application of treatments

The treatments were applied at three stages of crop cycle: (a) stage V4 (fourth trefoil open), (b) stage R5 (pre-flowering), and (c) stage R8 (grain filling) (Figure 1). The treatments were applied by hand spraying the shoot of the plants, up to the drain point. Both the method of application and the timing of the applications were chosen to reproduce the conventional management carried out by farmers in the field.

Inoculation of Colletotrichum lindemuthianum

Symptoms of the angular spot and powdery mildew diseases appeared spontaneously in all three crop cycles, assured by preliminary observations. However, it was not found for anthracnose. For this reason, for anthracnose development, spores of Colletotrichum lindemuthianum were inoculated, having a historic that there would be no natural occurrence of the disease. The isolate from C. lindemuthianum was provided by the Phytopathology Laboratory of Santa Catarina State University - CAV - in Lages/SC. The multiplication of C. lindemuthianum was carried out in Petri dishes containing PDA (Potato Dextrose Agar) medium and incubated at 22 ºC for 15 days under a null photoperiod (0 hours). Spore suspension was standardized to 1x10⁴ conidia/mL. The plants were inoculated by hand spraying at 30 days after sowing. After inoculation, the plants were wrapped in transparent plastic for 48 hours to reproduce a humid chamber, to stimulate spore germination and, consequently, to facilitate the development of the disease (Figure 1). This process was only carried out in the first crop cycle (from 02/16/22 to 05/20/2022), which was the only period when anthracnose was evaluated.

Assessments

Assessments of the incidence and severity of angular spot, anthracnose and powdery mildew were carried out every 7 (seven) days after the first symptoms appeared. The incidence of each disease was assessed by counting the total number of leaves and the number of leaves with respective typical symptoms. Severity was estimated in terms of the proportion of damaged leaf area, using diagrammatic scales drawn up for anthracnose [¹⁶], angular spot [¹⁷], and powdery mildew [¹⁸].

The agronomic attributes were assessed at harvest stage by counting the number of leaves, flowers and pods, plant height, stem diameter, first leaf height insertion, flowers and pods, thousand grain weight, and grain/plant weight.

The data on pod formation was transformed into the variables number of pods, and number of grains per pods. The incidence and severity values for all the three diseases were transformed into the Area Under the Disease Progress Curve (AUDPC), considering the total number of evaluations, using the formula described by Campbell and Madden [¹⁹]:

$$\text{AACPD}=\sum \text{[((xi+xi+1)/2)*(ti+1-t1))]}$$

where: n is the number of evaluations; X is the disease proportion and (ti+1-t1) is the interval between evaluations.

Data Analysis

The data underwent variance analyses using the F test (p<0.05), and the means were compared using Tukey’s test (p<0.05), with the R statistical software, version 3.3.0, using the GExpDes package (R Core Team, 2022).

RESULTS

Severity and incidence of anthracnose

In the case of the Perola cultivar, the treatment that proved to be the most effective for anthracnose severity was Calcarea carbonica, with the lowest values obtained in the Area Under the Disease Progress Curve (AUDPC=18.21) (Figure 2). Calcarea carbonica showed a 15% reduction in severity for cv. Perola when compared to the control (Figure 2). As for the incidence of anthracnose, the same trend was followed in the same cultivar, with Calcarea carbonica (AUDPC= 25.66), followed by Calcarea phosphorica (AUDPC= 26.92) and the control (AUDPC= 27.86) (Figure 2). Calcarea carbonica showed a 15% reduction in incidence when compared to distilled water (Figure 2).

Figure 2
Area under the disease progress curve for anthracnose (C. lindemuthianum). (A) severity (AUDPCS) and (B) incidence (AUDPCI) in Perola; (C) severity (AUDPCS) and (D) incidence (AUDPCI) in Campeiro. Lages, Santa Catarina, 2022. Calc-c: Calcarea carbonica; Calc-p: Calcarea phosphorica; Hepar: Hepar sulphur. Averages followed by different letters differ (Tukey, p<0.05).

In the Campeiro cultivar, the most effective treatment against anthracnose severity (Figure 2), was Calcarea phosphorica (AUDPC= 18.65). When it came to assessing the incidence of this disease, the same trend occurred again, with Calcarea phosphorica showing the lowest AUDPC values (24.63) when compared to the control and distilled water. However, shell limestone was statistically equal to Calcarea phosphorica, with an average of 25.85 when calculating AUDPC (Figure 2). Calcarea phosphorica showed a 30% reduction in severity when compared to the control. Calcarea phosphorica and shell limestone showed a 17% and 13% reduction, respectively, in incidence when compared to the control (Figure 2).

Severity and incidence of angular spot

It was found that plants of the Perola cultivar treated with Calcarea phosphorica showed reduction in severity caused by Pseudocercospora griseola. Calcarea phosphorica showed the lowest AUDPC value for the severity of angular spot (AUDPC= 21.05) and showed a 34% reduction when compared to the control (Figure 3). In terms of incidence of angular spot, also in the Perola variety, there was a statistical superiority of the plants treated with high dilutions of Calcarea phosphorica and Calcarea carbonica, with AUDPC values of 28.22 and 31.61, respectively. Calcarea phosphorica and Calcarea carbonica showed a reduction of 34% and 26%, respectively, when compared to the control (Figure 3).

Figure 3
Area under the disease progress curve for angular spot (P. griseola). (A) severity (AUDPCS) and (B) incidence (AUDPCI) in Perola; (C) severity (AUDPCS) and (D) incidence (AUDPCI) in Campeiro. Lages, Santa Catarina, 2022. Calc-c: Calcarea carbonica; Calc-p: Calcarea phosphorica; Hepar: Hepar sulphur. Averages followed by different letters differ (Tukey, p<0.05).

Different results were found for plants of the Campeiro cultivar (Figure 3), where plants treated with Hepar sulphur had the lowest AUDPC values for both severity and incidence of angular spot. In terms of severity, the plants treated with Hepar sulphur had an average AUDPC of 25.66 and showed a 25% reduction when compared to the control (Figure 3). As for incidence, the plants treated with Hepar sulphur and shell limestone showed statistically equal results: they were both the best treatments with averages of 37.33 and 35.88, respectively, and both showed a 15% reduction when compared to the control (Figure 3).

Severity and incidence of powdery mildew

Plants of cv. Perola submitted to high dilutions of Calcarea carbonica and shell limestone showed the lowest severity of powdery mildew. The results were statistically equal, with average AUPDC values of 25.75 and 29.71, respectively. Calcarea carbonica and shell limestone showed a reduction of 23% and 11,31%, respectively, when compared to the control (Figure 4). In the same cultivar, plants treated with Calcarea carbonica and Calcarea phosphorica showed lower average incidence of this disease, with AUPDC values of 32.5 and 34.88, respectively. These values represent a decrease of 11% and 5%, respectively, in the incidence of powdery mildew when compared to the control (Figure 4).

Figure 4
Area under the disease progress curve for powdery mildew (E. polygoni). (A) severity (AUDPCS) and (B) incidence (AUDPCI) in Perola; (C) severity (AUDPCS) and (D) incidence (AUDPCI) in Campeiro. Lages, Santa Catarina, 2022. Calc-c: Calcarea carbonica; Calc-p: Calcarea phosphorica; Hepar: Hepar sulphur. Averages followed by different letters differ (Tukey, p<0.05). Calc-c: Calcarea carbonica; Calc-p: Calcarea phosphorica; Hepar: Hepar sulphur. Averages followed by different letter, in the column, differ from each other (Tukey, p<0.05).

In terms of powdery mildew severity, for Campeiro cultivar, plants treated with Calcarea carbonica also had the lowest average severity according to the AUPDC, which was 34.00 and showed a 20% reduction in the severity when compared to the control (Figure 4). As for powdery mildew incidence, also in Campeiro cultivar, plants treated with Calcarea phosphorica and control without intervention, had the highest averages for incidence of the disease, which were 48.66 and 46.66, respectively, according to the AUPDC (Figure 4).

Productive potential

The plants of Perola cultivar showed significant differences when subjected to the treatments in the three growing cycles for the weight/plant variable. In the first cycle, the plants were more sensitive to Calcarea phosphorica, which was the treatment that increased production, with an average of 7.01 g per plant. In the second cycle, Perola plants were more sensitive to shell limestone, which was the best treatment, with the highest average grain weight per plant, namely 8.94 g/plant. In the third cycle, plants subjected to high-dynamized dilution of Hepar sulphur showed the highest grain weight/plant values, with an average of 2.84 g/plant (Table 1). When comparing the third cycles to the others, the plants showed a reduction in the values for grain weight per plant.

Table 1
Yield productive of the Perola and Campeiro cultivars, expressed by grain weight per plants and thousand grain weight (TGW), subjected to high-dynamized dilutions in different crop cycles. Lages, Santa Catarina State, 2023.

cv. Perola
	Grain weight/plant (g)			TGW (g)
Treatments	16/02/22 - 20/05/22	25/10/22 - 01/02/23	28/02/23 - 02/06/23	16/02/22 - 20/05/22	25/10/22 - 01/02/23	28/02/23 -2/06/23
Distilled water	6.21 b	6.95 c	1.78 c	278.80 ns	241.75 d	253.11 ns
Calc-c	5.62 c	5.35 e	1.71 c	281.10	253.23 b	253.17
Shell limestone	4.74 d	8.94 a	1.75 c	276.90	265.58 a	253.13
Calc-p	7.01 a	7.50 b	2.23 b	284.00	245.59 c	257.29
Hepar	5.47 c	5.94 d	2.84 a	281.00	239.23 d	253.07
Control	4.50 d	5.99 d	2.24 b	264.40	247.06 c	253.16
CV (%)	16.64	19.33	19.7	21.54	16.83	1.67
cv. Campeiro
Distilled water	4.51 b	4.31 c	3.11 a	223.20 ns	163.35 c	219.25 a
Calc-c	3.76 c	5.97 b	1.84 c	216.00	187.48 c	162.35 b
Shell limestone	4.63 b	6.85 a	1.71 c	221.70	227.65 a	163.39 b
Calc-p	4.61 b	6.07 b	1.73 c	220.20	219.55 a	164.34 b
Hepar	5.71 a	4.56 c	1.81 c	221.80	203.36 b	162.34 b
Control	3.57 c	6.09 b	2.73 b	210.50	236.12 a	206.69 a
CV (%)	15.69	23.61	26.34	18.5	13.24	14.5

• Calc-c: Calcarea carbonica; Calc-p: Calcarea phosphorica; Hepar: Hepar sulphur. Averages followed by different letter, in the column, differ each other (Tukey, p<0.05);
• ^ns
  not significant.

As for thousand grain weight (TGW), also for Perola cultivar, it was found that the plants in the first and third cycles showed no statistical differences when subjected to the treatments. However, in the second cycle, those subjected to the shell limestone showed the highest WTG value (265.58 g), and this treatment was considered superior to the others (Table 1).

For plants of the Campeiro cultivar, there were statistical differences in grain weight/plant in all the cycles. In the first cycle, plants treated with Hepar sulphur showed an average of 5.71 g/plant. In the second cycle, those treated with shell limestone were superior to the others with an average of 6.85 g/plant. And in the third cycle, those treated with distilled water had the highest productive potential, with an average of 3.11 g/plant. Once again, plants conducted in the third growing cycle showed a reduction in grain weight/plant when compared to those grown in the other cycles (Table 1).

For TGW, only in the first growing cycle, the plants did not show significative differences when subjected to the treatments. In the second cycle, those treated with shell limestone, Calcarea carbonica and control without intervention were statistically equal and showed the greatest increases for the characteristic with an average of 227.65, 219.55 and 236.12 g, respectively. In the third cycle, plants subjected to the two controls, distilled water and no intervention, showed the highest averages: 219.25 and 206.69 g, respectively (Table 1).

Plants of Perola cultivar showed statistical differences for number of grains/pods, only in the first growing cycle. The best results were found in plants treated with distilled water and shell limestone, with averages of 5.11 and 5.06 grains/pods, respectively. As for number of pods/plant, the plants showed statistical differences only in the second growing cycle (Table 2); those treated with shell limestone obtained the highest average of 7.63 pods/plant. This result confirms the trend for the number of grains/pods found in the first growing cycle, when shell limestone also presented the highest averages.

Table 2
Grain production per pod and pods per plant in the three crop cycles of the Perola and Campeiro bean cultivars. Lages, Santa Catarina State, 2023.

cv. Perola
	Grain/pod (N)			Pod/plant (N)
Treatments	16/02/22 - 20/05/22	25/10/22 - 01/02/23	28/02/23 - 02/06/23	16/02/22 - 20/05/22	25/10/22 - 01/02/23	28/02/23 - 02/06/23
Distilled water	5.11 a	4.72 ns	3.51 ns	4.33 ns	6.27 b	2.02 ns
Calc-c	4.51 ab	4.78	3.15	4.41	4.54 c	2.15
Shell limestone	5.06 a	4.41	3.35	3.75	7.63 a	2.31
Calc-p	4.46 ab	4.75	3.65	5.16	6.52 b	2.17
Hepar	3.91 b	4.61	3.90	3.83	4.41 c	2.88
Control	4.70 ab	5.29	3.30	3.58	4.61 c	2.69
CV (%)	13.37	6.56	7.76	21.84	20.72	14.33
cv. Campeiro
Distilled water	4.95 ns	4.17 ns	4.40 ns	4.50 ns	5.38 c	3.12 ns
Calc-c	4.41	4.42	3.5	4.08	7.12 a	3.24
Shell limestone	4.56	4.46	3.98	4.66	6.84 b	2.67
Calc-p	4.09	5.03	4.25	4.75	5.25 c	2.52
Hepar	4.66	4.43	4.29	5.41	5.14 c	2.81
Control	4.79	4.32	4.31	3.41	6.71 b	3.08
CV (%)	16.58	6.68	8.15	25.6	16.71	9.75

• N: number. Calc-c: Calcarea carbonica; Calc-p: Calcarea phosphorica; Hepar: Hepar sulphur. Averages followed by different letter, in the column, differ from each other (Tukey, p<0.05);
• ^ns
  not significant.

On the other hand, plants of Campeiro cultivar, showed no statistical differences in terms of number of grains/pods in any growing cycle and under any treatment. However, there were differences in the number of pods/plant, but only in the second growing cycle (Table 2). There was statistical superiority in plants subjected to Calcarea carbonica, which presented 7.12 pods/plant. This was the treatment that most influenced this characteristic (Table 2).

DISCUSSION

The average values for temperature (20.13 ºC) and moisture (80%) during the occurrence of the anthracnose in the first cycle may explain the fact that the disease established itself in the crop after inoculation, but did not show high severity values in the plants. The year 2022 was marked by the La Niña phenomenon, which is characterized by dry conditions, especially in the southern region of Brazil. This specific climatic condition may explain the low severity of the anthracnose, since the conditions were not entirely favorable for the establishment of the pathogen. The disease progress is higher with temperatures between 13 ºC to 27 ºC, with optimal temperature at 17 ºC. In addition, the pathogen (C. lindemuthianum) requires high air humidity - around 90% - combined with frequent precipitation [²⁰]. The respective growing season was marked by few intervals of moisture and adequate leaf wetness for the fungus development, which may have triggered the low severity of anthracnose in the bean crop.

When we see the infection of Pseudocercospora griseola, we found that, plants in the second growing cycle showed the lowest averages for severity of the disease, which may be also due to the unfavorable climatic conditions faced by P. griseola. Infection and disease development are favored at temperatures between 20 ºC and 28 ºC, with optimal temperature near to 24 ºC, associated with periods of high humidity [²¹]. The temperature average of the respective period (second cycle) was 17.95 ºC, which is below the rage required by the fungus. In addition, the period in which the cycle was carried out was marked by dry weather, coupled with the fact that the cycles were grown in a protect environment - a greenhouse - which reduces wetness that is necessary for the establishment of the fungus.

Looking at the findings for angular spot and powdery mildew, it was found that the plants grown in the third cycle, had the highest averages for severity for both diseases. This fact directly interfered with the yield of the cultivars, since the lowest yields were also found in comparison to the other cycles. The average temperature in the third cycle was 18.91 ºC, higher than the average found in the second cycle. In addition to the temperature, the crop’s water management was carried out through irrigation in all cycles, which may have helped the dissemination of the fungal spore, culminating in the accelerated development of the diseases. With the higher establishment of the diseases in the crop, the plants were unable to show their full productive potential, which led to lower yields in all treatments and in both cultivars. Also, the experiments in the three growing cycles were carried out in greenhouses, in a semi-controlled environment. This kind of system increases the temperature and provides greater protection from rain, reducing leaf wetness and disfavoring the establishment of some diseases on leaves. However, these conditions favor the development of powdery mildew [²²]. This can be because conidia are easily spread by wind or rain, but high rainfall is unfavorable for conidia production as it can damage the conidiophores. In addition, the temperature inside the greenhouse remains within the pathogen's optimum growth range (20 to 25 ºC), creating a favorable microclimate for its development [²³].

The results founded to development and productivity of the plants show us a high oscillation between the productivity values in the three growing cycles for both cultivars, which can be explained by the climatic conditions during the different growing periods and the intrinsic characteristics of the seed itself. In the first cycle, the average temperature was 20.13 ºC, in the second growing cycle the temperature was 17.95 ºC and in the third cycle, it was 18.91 ºC. According to Pereira and coauthors [²⁴], many factors influence the performance of bean plants, especially temperature and hydric conditions, precipitation in field conditions and irrigations/wetting in greenhouse conditions. Temperature directly affects the development of the bean crop by interfering in different physiological stages, especially in flowering and grains filling. The average temperature during the crop cycle should range between 20 and 22 ºC, and temperatures above 24 ºC during the flowering and pod formation stages, can have negatives effects on grain yield [²⁵]. However, very low temperatures can compromise seed germination, or if they occur during the plant’s vegetative phase, growth can be harmed, culminating in small plants [²⁶].

It is known that high-dynamized dilutions can be used as management strategies for various diseases and against harmful agents that damage the plants. Many studies agree with this claim [²⁷]. These authors used the high-dynamized dilutions of Calcarea carbonica and Phosphorus at potencies of 6, 12, 24, 36 and 48 CH in bean plants to manage Sclerotinia sclerotiorum, the causal agent of white mold. The results showed that Calcarea carbonica 6 CH and Phosphorus, in all the dynamizations tested, reduced the intensity of white mold when compared to the control. In addition, Calcarea carbonica 12 and 24 CH reduced plant death caused by white mold by 61% when compared to the control [²⁶]. Studies carried out by Rissato and coauthors [²⁸] evaluated antimicrobial activity and white mold control using Phosphorus and Calcarea carbonica at potencies in 6, 12, 24, 36 and 48 CH in bean plants (Phaseolus vulgaris L.). They found that the plants treated with Calcarea carbonica 12 and 48 CH showed an 83% reduction in the progress of the disease when compared to distilled water. In addition, Calcarea carbonica 48 CH inhibited the production of fungal sclerotia. Others studies Toledo and coauthors [¹²], when evaluating powdery mildew in two different tomato genotypes, found that Ferrum sulphuricum at 6, 12, 24, 48, 72 and 96 CH dynamizations reduced the disease according to AUDPC values. For the Santa Clara tomato genotype, the homeopathies reduced the disease by 48%, while the homeopathies reduced powdery mildew by 31% for the Cedro genotype.

From time to time, the plants treated with distilled water performed better when compared to the high-dynamized dilutions. This may be due to the fact that high-dynamized dilutions may have a negative effect on the organism in which they are applied, probably because the law of similarity was not attending. Therefore, the effect observed for distilled water may be related to the lack of similarity between the organism treated at the time and the high dilutions used. High-dynamized dilutions may have no effect and/or cause negative effects because they do not fully meet the similarity with the organism at that particular moment [²⁹]. However, several studies about the use of high-dynamized dilutions in crops of economic importance corroborate the results found in the present study, that is, high-dynamized dilutions act beneficially. Verdi and coauthors [¹¹] analyzed rice plants (Oryza sativa) subjected to Magnetitum CCLM7 and Arsenicum tartaricum CCLM6 homeopathies and found that the use of these preparations resulted in higher crop yields, with averages of 8906.47 Kg ha^-1, when compared to the use of pesticides and water, which averages of 7710.88 Kg ha^-1 e 6976.07 Kg ha^-1, respectively. Also, studies about the effect of Sulphur, Arsenicum album, Silicea terra, and Phosphorus (all at 30 CH) on the yield of soybeans (Glycine max), showed that the Arsenicum, Phosphorus, and Silicea terra increased the number of pods per plant when compared to water [30].

CONCLUSION

High-dynamized dilutions cause changes in production potential, such as thousand grain weight and weight/plant; shell limestone, Calcarea carbonica, and Calcarea phosphorica stand out as the treatments with the highest influence on the above-mentioned characteristics. The Calcarea carbonica and Calcarea phosphorica treatments were also more effective in reducing the severity and incidence of anthracnose, angular spot and powdery mildew in the two study cultivars.

The results highlight the potential of dynamized high dilutions, particularly of shell limestone, Calcarea carbonica and Calcarea phosphorica, as tools to improve characteristics related to the productive potential and management of certain diseases in beans.

These treatments can be integrated into sustainable agricultural practices to increase productivity and reduce dependence on chemical inputs, especially with regard to the management of anthracnose, angular spot and powdery mildew.

Future research could focus on exploring the effectiveness of these treatments in a wider range of crops and environmental conditions, as well as assessing their long-term effects on soil health and crop resilience.

• Funding:
  The study was supported by FAPESC through the PAP 2021 project, conv. FAPESC/2021TR879.

Acknowledgments:

To the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for the master’s scholarship to the first author.

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• Editor-in-Chief: Bill Jorge Costa

• Associate Editor: Adriel Ferreira da Fonseca

Publication Dates

• Publication in this collection
  24 Mar 2025
• Date of issue
  2025

History

• Received
  07 Dec 2023
• Accepted
  24 Jan 2025