Ultra high diluted arsenic reduces spore germination of Alternaria brassicicola and dark leaf spot in cauliflower

Abstract

A major problem in cauliflower crop is the fungus Alternaria brassicicola, which causes dark leaf spot on Brassicaceae family. The current use of copper salts in agriculture is questioned. In fact, these products present some disadvantages, connected mainly with their deposits in the soil and toxicity on plants. This work investigated the effects of arsenic treatments, in ultra high diluted form (UHD), prepared by a process of repeated dilution and succussion (shaking), through: 1) in vitro germination experiments, where spores of A. brassicicola were suspended in the treatments; 2) in planta experiments and 3) a field trial, where cauliflower plants infected by the fungus were sprayed with treatments. The results showed that ultra high dilutions of arsenic (where no more molecules of this substance are present) were effective in all the experiments, inhibiting spore germination by 60.0%, controlling fungal disease in in planta experiments (relative efficacy of 42.1%), and, in field trial, decreasing the mean infection level in cauliflower heads by 45.7% and 41.6% in artificially inoculated and naturally infected plants, respectively. This is the first study to demonstrate that ultra high dilutions effectively reduce in vitro spore germination and infection of A. brassicicola in cauliflower plants, both under controlled conditions and in the field. Our research is still very experimental, however, in light of the significant results obtained with ultra-diluted arsenic, and given that its extreme high dilution level precludes any toxicity or accumulation in the environment, the use of UHDs could be considered a potential and reliable approach for sustainable agriculture.

Systemic Agro-Homeopathy: A New Approach to Agriculture

“…In this context, agro-homeopathy could be an integrative approach to improve organic agriculture since homeopathic treatments, due to their ultrahigh dilutions, have few or no ecological side effects. In recent years there has been a growing interest of the scientific community in such methods, and many scientific studies have been performed to evaluate the effect of homeopathic treatments on plants [1][2][3][4][5][6][7][8][9][10]. Different plant model systems have been set up both in basic research (in vitro germination and growth models with healthy, impaired, and phytopathological models) [1][2][3][4][5] and in application research (field trials) [2].…”

The Influence of Ultra-High Diluted Compounds on the Growth and the Metabolites of Oriza sativa L.

“…Moreover, UHDs are harmless to humans, livestock and different ecosystems as they cause no pathogen resilience, and in long-term, they increase the product efficiency (18)(19)(20)(21)(22)(23)(24)(25). They may also cause a remarkable increase in stem growth and stability, seed germination rate, survival of buds, defense of enzyme expressions, and resistance to a variety of mutagenic agents (25)(26)(27)(28)(29)(30).…”

Effect of Nosodes on Lettuce, Parasitized or Not by Meloidogyne enterolobii

“…7,8 On the other hand, nosodes had no effect on diseases caused by the bacterium Pseudomonas syringae Van Hall, 9 or the fungi A. solani, Alternaria brassicicola Wiltshire, Phytophthora infestans de Bary, Fusarium guttiforme Nirenberg and O'Donnell, and Macrophomina phaseolina Goid., in tomato, potato, pineapple, soybean and cauliflower plants, in greenhouse and field experiments. [10][11][12][13][14] The more numerous reports of no effects should not lead one to infer that nosodes are ineffective against plant diseases. Plant pathologists are aware of several factors that modulate the efficacy of any therapeutic product: the dosage of the ingredient; the weather conditions in the field; the amount of the pathogen inoculum; and the genetic diversity of the plant and pathogen, among others.…”