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Int J High Dilution Res 2011; 10(34): 37-45
37
Original Article
Pathogenetic trial of boric acid in bean
and tomato plants
Solange Monteiro de Toledo Piza Gomes Carneiro1,
Euclides Davidson Bueno Romano1, Tiago Henrique dos Santos Garbim1,
Bruno Garcia de Oliveira1, Marcus Zulian Teixeira2
(1) Agronomic Institute of Paraná, IAPAR, PR, Brazil
(2) Medical School of University of São Paulo, FMUSP, SP, Brazil
ABSTRACT
Background: homeopathy is held in organic agriculture as a means to control disease and
plagues. However, different from doctors, who have works on materia medica and repertories
available to choose the most suitable homeopathic medicine for each patient, agronomists do not
yet have an equivalent Homeopathic Materia Medica of Plants (HMMP) describing symptoms
observed in plants. Aim: the aim of this study was to carry out a homeopathic pathogenetic trial
(HPT) in plants comparing the effects elicited by boric acid in ponderable dose and dilution 6cH in
two different plant species, namely bean and tomato cultivars. Methods: 4 tests were carried
out, 2 on tomato and 2 on bean plants, which received 1 to 6 applications of treatments. Results:
there were differences between both species regarding their sensitiveness to boric acid . None of
the tomato plants that received Boron 6cH showed symptoms, differently from bean plants. On
the other hand, in tests of ponderable doses of boric acid, tomato plants exhibited 3 symptoms
more than bean plants. A higher number of bean plants exhibited symptoms with boric acid in
ponderable dose than in dilution 6cH). Nos ensaios com feijoeiro, um maior número de plantas
apresentou sintomas após o tratamento com ácido bórico na dose ponderal do que com ácido bórico
6cH. Conclusions: these results suggest that the elaboration of a HMMP must take into account
the species in which symptoms were obtained. Moreover, HPTs in plants must be carried out with
both ponderable doses and high dilutions in order for differences in sensitiveness among species
be better identified.
Palavras-chave: Phaseolus vulgaris, Solanum lycopersicum, Homeopathic pathogenetic trial.
Introduction
Since the publication in 1999 of Normative Instruction No 7 by Brazilian Ministry of Agriculture [1],
homeopathy is rated a practice suitable for the control of disease and plagues in organic agriculture. However,
different from the case of doctors, who have works on materia medica and repertories available for the choice
of the most suitable homeopathic medicine for each patient, agronomists do not have an equivalent
Homeopathic Materia Medica of Plants (HMMP) describing symptoms obtained in plants. For this reason, as
a rule, the choice of homeopathic remedies for plants has been grounded on analogies with the medical
materia medica [2]. If on the one hand, this allowed for a quick application of homeopathy in agriculture, on
the other it does not take into account the typical symptoms exhibited by plants and that naturally are
remarkably different from the ones of human beings.
Int J High Dilution Res 2011; 10(34): 37-45
38
The guidelines laid out in Organon of medicine [3] regarding homeopathic pathogenetic trials (HPTs) make
explicit the need to learn the true pathogenetic power of drugs (“pure effects of medicines”) through tests on
individuals in which they will be used (“to constitute an artificial disease as similar as possible to the totality
of the main symptoms of the natural disease to be healed”). To illustrate, §105 establishes that “the second
point of the business of a true physician related to acquiring a knowledge of the instruments intended for the
cure of the natural diseases, investigating the pathogenetic power of the medicines, in order, when called on
to cure, to be able to select from among them one, from the list of whose symptoms an artificial disease may be
constructed, as similar as possible to the totality of the principal symptoms of the natural disease sought to be
cured”. In §106 it is stated: “The whole pathogenetic effect of the several medicines must be known; that is to
say, all the morbid symptoms and alterations in the health that each of them is specially capable of
developing in the healthy individual must first have been observed as far as possible, before we can hope to be
able to find among them, and to select, suitable homoeopathic remedies for most of the natural disease”[3].
In this way HPTs in plants can be a significant contribution to the development of homeopathy in agriculture
[4,5], since it will allow applying the principle of similitude on the grounds of the characteristic symptoms of
plants.
Plants with agricultural interest belong to different botanic genera and species, and such diversity might lead
to different pathogenetic symptoms. The homeopathic pure materia medica reports the doses used in HPTs,
the frequency of intake of drugs and when available, also data stemming from intoxications. Moreover, it is
recorded the name of volunteers and the symptoms exhibited by each one of them [6]. Making a parallel with
plants, the structure of a HMMP ought to take into account the symptoms exhibited by different families and
species of plants after taking some drug in, as well as (ponderable and high-diluted) the corresponding doses
and frequency of application. Many plant species and cultivars show differences in their sensitiveness to the
toxicity of mineral elements [7-10] a fact that can be advantageously used in the elaboration of a HMMP.
Boron (B) is a micronutrient essential for the growth of plants. It regulates the activity of the cell membrane,
the rate of cell development, cell division, the synthesis of proteins and the transportation of carbohydrates
from the leaves to other organs [7,11]. Since it is a substance used in agriculture, it is important to assess the
relative sensitiveness of different species of plants subjected to HPTs of boron in ponderable and high -diluted
doses.
In this way, the aim of this study was to carry out a HPT on plants by comparing the symptoms exhibited by
bean and tomato cultivars after the administration of boric acid in ponderable dose and dilution 6cH.
Materials and Methods
Four tests were carried out, 2 in tomato and 2 in bean plants.
HPT in tomato plants: tests were carried out in a greenhouse, with one plant per vase. Variety chosen was
Santa Clara Miss Brasil. The application of the treatments started when plants had shown the fourth leaf.
The experimental design was entirely randomized, with 7 treatments and 4 repetitions (1 plant per repetition)
in tests with ponderable dose and 10 repetitions in tests with high dilution. Treatments consisted in a number
of spray applications of boric acid every 4 to 6 days. Plants subjected to treatment 1 received only one
application, treatment 2, 2 applications and so on up to 6 applications. Plants receiving control treatment
were treated only with purified water in spray application in 6 different days similarly to treatment 6.
Equipment for application was a 500 ml hand-operated sprayer, and each treatment had your own device.
Int J High Dilution Res 2011; 10(34): 37-45
39
Spraying in all treatments continued until running down. In order to avoid contamination during spraying,
treatments were carried out separately in a different room of the greenhouse. Assessment was accomplished
through the description of the observed symptoms according to Honey’s classification [12]. Solutions were
prepared with boric acid in concentration 74.16mg/100 ml purified water. In the first test, plants were applied
boric acid in ponderable dose and in the second test diluted and agitated boric acid. In the latter, the solution
of boric acid 74.16mg/100ml was prepared following the Hahnemannian centesimal scale [13] in purified
water. Dilution 6cH was used in this study and it was prepared on the same day it was applied, after being
agitated further 30 times in the greenhouse before application.
HPT in bean plants: the design of both tests in bean plants was the same as in tomato plants. Cultivar used
was “Carioca”, which has undetermined growth habit, matted light chestnut hued seeds and havana hued
streaks. It was sowed 1 plant per vase. The test began when the third trifoliate leave was fully developed.
Results
Plants that received control treatment (purified water) in all tests showed no symptoms. Symptoms observed
occurred in the leaves of plants treated with boric acid (Table 1), whereas in test “tomato-6cH” no plant
exhibited any symptom whatsoever.
Table 1: description and occurrence of symptoms in plants per treatment
Percentage of plants in each treatment exhibiting symptoms
Tomato plants – ponderable dose
Bean plants – ponderable dose
Bean plants- 6cH
Leaf symptom
T1
T2
T3
T4
T5
T6
T1
T2
T3
T4
T5
T6
T1
T2
T3
T4
T5
T6
• Irregular necrotic lesion
- cream
25
25
0
25
25
25
0
0
0
0
0
0
0
0
0
0
0
0
• Irregular necrotic lesion
- light chestnut
50
100
100
100
100
100
75
75
75
100
75
100
10
40
30
20
40
20
•Irregular necrotic lesion
- dark chestnut
75
50
75
100
100
100
75
100
100
100
100
100
10
0
40
20
30
10
• Localization of necrotic lesions
- margin of foliole
100
100
100
100
100
100
100
100
100
100
100
100
0
20
40
30
30
10
• Localization of necrotic lesion
- side of foliole
100
100
100
100
100
100
75
100
100
75
100
100
10
30
30
20
30
10
• Chlorosis around necrosis
75
100
100
100
100
100
75
100
100
100
100
100
0
0
10
0
20
0
• Necrosis on the tips of folioles
100
100
100
100
100
100
100
100
100
100
100
100
0
10
30
10
0
0
•Light-green islands in foliar tissue
0
100
75
100
75
25
0
0
0
0
0
0
0
0
0
0
0
0
• Epinasty
0
0
0
75
75
0
0
0
0
0
0
0
0
0
0
0
0
0
Int J High Dilution Res 2011; 10(34): 37-45
40
In tests with boric acid in ponderable doses, all bean (Figure 1) and tomato (Figure 2) plants in treatments 1
to 6 exhibited at least 1 symptom, while in several cases one same plant exhibited more than one symptom.
Figure 1: Necrotic lesion in bean plant
The 2 species studied differed regarding sensitiveness to boric acid not only in dilution 6cH but also in
ponderable dose, since tomato plants exhibited 3 symptoms more than bean plants: cream-hued necrotic
lesion, light-green islands and epinasty. Regarding the remainder of symptoms, rate of occurrence was similar
among all plants under study.
Figura 2: Necrosis on the tips of tomatoes folioles.
Int J High Dilution Res 2011; 10(34): 37-45
41
Similar to test “bean plant – ponderable dose”, also samples in test “bean plant – 6cH” did not exhibited
symptoms cream-hued necrotic lesion, light-green islands and epinasty. The percentage of plants exhibiting
symptoms in test “bean plant – 6cH” was much lower than in test “bean plant – ponderable dose” (Table 2)
particularly regarding symptoms “chlorosis around necrosis”and “necrosis on the tips of folioles”. No symptom
that was not observed with ponderable dose was observed in tests with 6cH.
Table 2 - Occurrence of symptoms in all treated plants
Leaf symptom
Tomato plants
(ponderable dose)
Bean plants
(ponderable dose)
Bean plants
(6cH)
• Irregular necrotic lesion
- cream
5 (20,8)
0
0
• Irregular necrotic lesion
- light chestnut
22 (91,6)
20 (83,3)
16 (26,6)
•Irregular necrotic lesion
- dark chestnut
20 (83,3)
23 (95,8)
11 (18,3)
• Localization of necrotic lesions
- margin of foliole
24 (100)
24 (100)
13 (21,6)
• Localization of necrotic lesion
- side of foliole
24 (100)
22 (91,6)
13 (21,6)
• Chlorosis around necrosis
23 (95,8)
23 (95,8)
3 (5,0)
• Necrosis on the tips of folioles
24 (100)
24 (100)
5 (8,3)
• Light-green islands in foliar tissue
15 (62,5)
0
0
• Epinasty
6 (25,0)
0
0
Discussion
Necrotic spots and mottled chlorosis are symptoms of toxicity by boron, and they appear on the areas of leaves
with most transpiration [11]. Differences in sensitiveness to boron among plant species have been reported in
the literature. Cereals and gramineous plants are more sensitive to high levels of boron. Barley has the
highest sensitiveness followed by wheat and oat [7], whereas cotton and sorghum are rated quite tolerant [14].
In this study, it was observed a higher sensitiveness to boron in ponderable dose in tomato plants, which
exhibited 3 symptoms more than bean plants.
Besides differences in sensitiveness to boron among different species of plants, it was also observed
differences among cultivars of a same species. Carneiro et al [15] found that 3 cultivars of bean plants reacted
in different manners to intoxication with boric acid. Eldorado cultivar always showed a lesser number of
symptoms independently from the dose employed, whereas Uirapuru and Carioca cultivars were more
sensitive. Such differentiated sensitiveness has been reported in the literature also for other species of plan ts
[16,17].
Int J High Dilution Res 2011; 10(34): 37-45
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Ours is the first report of differences in sensitiveness between species to high dilutions of boron. Tomato
plants showed no symptoms when treated with dilution 6cH, whereas bean plants exhibited the same kind of
symptoms as when treated with ponderable dose although in a lesser number of samples. Rossi et al [18]
studied the effect of homeopathic preparations on the productivity of potatoes. These authors observed that
out of 3 cultivars tested, only 1 was affected by the homeopathic preparation. In our study only 1 cultivar of
each species was used, therefore it cannot be established whether the lack of symptoms in test “tomato plant –
6cH” was due to the specificity of the cultivar employed or whether it is a general trait of tomato plants.
In this study, only primary symptoms developed in foliar tissues were observed and to describe them the
symptomatology presented by Salgado and Amorim [12] proved to be adequate. However, it is possible that
other alterations also occurred but were not visually detected. Plants have an ability to react through
metabolic changes that are not visually detectable [19]. Some authors have reported changes in the contents
of secondary metabolites in plants elicited by high-diluted substances [20-22]. However, taking into account
that the choice of the homeopathic medicine most suitable to a farm/culture/crop will depend on the visual
identification of symptoms in plants at the field, we did not hold necessary to evaluate in this study
alterations not visually identifiable.
The results observed in this study together with data in the literature regarding differences in symptoms of
intoxication among plant species and cultivars [7-10,14-17] can be used in the elaboration of a HMMP
describing the typical symptoms exhibited by plants [23]. Such HMMP grounded on the symptomatology of
plants has the advantage of following Hahnemann’s guidelines [3] in Organon §144: “From such a materia
medica everything that is conjectural, all that is mere assertion or imaginary should be strictly excluded;
everything should be the pure language of nature carefully and honestly interrogated”.
Symptoms obtained in HPTs in plants as grounds for a therapeutic application of the principle of similitude
have already been employed by Betti et al [24] to increase the resistance of tobacco to TMV. The differences in
the response to intoxication by a given substance among different species of plants described in the literature
and in this study regarding the pathogenetic experimentation of boric acid and more particularly of Boron
6cH strengthen the need to test substances in the individuals/species where they will be used for therapeutic
purposes according to the principle of similitude. Moreover, from these results it is possible to infer that the
indication of homeopathic medicines will have to take into account such differences due to the requirement of
individualization of treatment. Further studies are needed to verify this hypothesis.
The results presented in this article suggest that the elaboration of a HMMP requires taking notice of the
species where symptoms were obtained. Another significant point is that HPTs in plants ought to be carried
with both ponderable doses and high dilutions in order to identify more clearly differences in sensitiveness
among species, and a larger number of symptoms can be observed and recorded, thereby allowing for a more
accurate application of therapeutic similitude in each botanical species. In this way, it will be possible to score
the relative significance of each symptom for a given drug as it is done in the traditional homeopathic materia
medica.
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Experimentação patogenética de ácido bórico em tomateiros e feijoeiros.
RESUMO
Introdução: A homeopatia é considerada como uma prática para manejo de doenças e pragas na agricultura
orgânica. No entanto, ao contrário dos médicos que dispõe das Matérias Médicas e Repertórios para a escolha
do medicamento homeopático mais adequado para o paciente, os agrônomos não dispõem de uma Matéria
Médica Homeopática de Plantas (MMHP) com sintomas observados em vegetais. Objetivos: O objetivo deste
trabalho foi realizar uma experimentação patogenética homeopática em vegetais, comparando os sintomas
apresentados por uma cultivar de feijoeiro e uma cultivar de tomateiro após a administração de ácido bórico
em dose ponderal e na dinamização 6cH. Métodos: Foram conduzidos quatro experimentos, dois com
tomateiro e dois com feijoeiro, sendo que as plantas receberam entre uma a seis pulverizações dos
tratamentos. Resultados: Observaram-se diferenças entre as espécies quanto à sensibilidade ao ácido bórico:
nenhuma planta de tomateiro que recebeu Boro 6cH apresentou sintomas, diferentemente do feijoeiro. Por
outro lado, nos ensaios com ácido bórico em dose ponderal o tomateiro apresentou três sintomas a mais que o
feijoeiro. Nos ensaios com feijoeiro, um maior número de plantas apresentou sintomas após o tratamento com
ácido bórico na dose ponderal do que com ácido bórico 6cH. Conclusões: Estes resultados sugerem que na
elaboração de uma Matéria Médica Homeopática de Plantas (MMHP) deve ser considerada a espécie vegetal
na qual os sintomas foram obtidos. Além disso, as experimentações patogenéticas homeopáticas em vegetais
devem ser realizadas tanto com doses ponderais quanto com doses dinamizadas, a fim de que as diferenças na
sensibilidade entre espécies possam ser mais bem detectadas.
Palavras-chave: Phaseolus vulgaris, Solanum lycopersicum, patogenesia, homeopatia.
Int J High Dilution Res 2011; 10(34): 37-45
45
Experimentación patogenetica de ácido Bórico en tomateros y frijoleros
RESUMEN
Introducción: La homeopatia es usada en la práctica para el manejo de enfermedades y plagas en la
agricultura orgánica. Pero, al contrario de los médicos que disponen de Materias Médicas y Repertorios para
la elección del medicamento homeopático mas adecuado para el paciente, los agrónomos no disponen de una
Materia Médica Homeopática de Plantas (MMHP) com sintomas observados em vegetales. Objetivos: El
objetivo de este trabajo fue realizar una experimentación patogenética homeopática en vegetales, comparando
los sintomas presentes en un cultivo de frijoles y de tomates después de administrar ácido bórico en dosis
ponderales y en la dinamización 6 CH. Métodos: fueron realizados cuatro experimentos, dos con tomateros y
dos con frijoleros y las plantas recibieron seis pulverizaciones con las sustancias del tratamiento.Resultados:
Seobservaron diferencias entre las espécies en relación a la sensibilidad al ácido bórico: ninguna planta de
tomatero que recibió Boro 6 CH presentó sintomas, al contrario de los frijoleros. Por outro lado en los ensayos
con ácido bórico ponderal los tomateros presentaron tres sintomas más que los frijoleros. En los ensayos con
frijoleros um mayor número de plantas presentó sintomas después del tratamiento con ácido bórico en la
dosis ponderal en relación a los tratados com Boro 6 CH. Conclusión: estos resultados sugieren que en la
elaboración de una Materia Médica Homeopática de Plantas (MMHP) debe ser considerada la espécie vegetal
en la que los sintomas fueron obtenidos. Además, las experimentaciones patogenéticas homeopáticas en
vegetales deben ser realizadas tanto con dosis ponderales como con dosis dinamizadas a fin de que las
diferencias en la sensibilidad entre espécies puedan ser mejor detectadas..
Palabras-clave: Phaseolus vulgaris, Solanum lycopersicum, Experimentación patogenética homeopática.
Licensed to GIRI
Support: authors declare that this study received no funding
Conflict of interest: authors declare there is no conflict of interest
Received: 02 October 2011; Revised: 10 March 2011; Published: 30 March 2011.
Correspondence author: Solange Gomes Carneiro, solange_carneiro@iapar.br
How to cite this article: Carneiro SMTPG, Romano EDB, Garbim THS, Oliveira BG, Teixeira MZ. Pathogenetic trial of
boric acid in bean and tomato plants. Int J High Dilution Res [online]. 2011 [cited YYYY Month dd]; 10(34): 37-45.
Available from: http://www.feg.unesp.br/~ojs/index.php/ijhdr/article/view/422/458