Using Plant-Based Preparations to Protect Common Bean against Halo Blight Disease: The Potential of Nettle to Trigger the Immune System

Halo blight disease of beans (Phaseolus vulgaris L.), caused by the bacterium Pseudomonas syringae pv. phaseolicola (Pph), is responsible for severe losses in crop production worldwide. As the current agronomic techniques used are not effective, it is necessary to search for new ones which may prevent disease in common bean. In this study, we challenged four plant-based preparations (PBPs), with no other agronomic uses, as they come from industrial waste (grapevine pomace (RG) and hop residue (RH)) or wild plants (Urtica dioica (U) and Equisetum sp. (E)), to be used as immune defense elicitors against Pph in common bean. After studying their inhibitory effect against Pph growth by bioassays, the two most effective PBPs (RG and U) were applied in common bean plants. By measuring the total H2O2, lipid peroxidation, and antioxidant enzymatic activities, as well as the expression of six defense-related genes—PR1, WRKY33, MAPKK, RIN4, and PAL1, it was observed that U-PBP application involved a signaling redox process and the overexpression of all genes, mostly PR1. First infection trials in vitro suggested that the application of U-PBP involved protection against Pph. The elicitation of bean defense with U-PBP involved a decrease in some yield parameters, but without affecting the final production. All these findings suggest a future use of U-PBP to diminish halo blight disease.

Pathogenetic trial of boric acid in bean and tomato plants

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.

SOSIALISASI PEMANFAATAN LIMBAH TANAMAN BUNCIS (PHASEOLUS VULGARIS, L) SEBAGAI PUPUK CAIR DI DESA TONGKOK

This community service activity is motivated by the large amount of waste from bean plants in Tongkok Village, Lahat Regency which has not been used optimally, especially as liquid fertilizer. Waste from the bean plant is disposed of, burned and not used . This causes a high volume of waste and environmental pollution. Therefore, the pkm stkip pgri lubuklinggau team tried to socialize the use of bean plant waste (phaseolus vulgaris, l) as liquid fertilizer in tongkok village. This PKM has been carried out by involving partners, namely the Tongkok village community and is enthusiastically followed. The output target to be achieved by the PKM team is to increase community values ​​and publications. In its implementation, it uses theoretical and practical methods starting from the preparation stage, providing materials and practices for making liquid fertilizer for bean plant waste

Phenotypic and molecular screening of dry bean (Phaseolus vulgaris L.) breeding lines for resistance to bean common mosaic virus and bean common mosaic necrosis virus

Bean common mosaic virus (BCMV) and bean common mosaic necrosis virus (BCMNV) are among the most economically important virus species infecting common bean. The use of resistant plant cultivars is the most effective way to control these viruses. National dry bean breeding studies have been conducted by seven different governmental agricultural research institutes in Turkey, and advanced breeding lines have been developed by using the selected local dry bean populations and crossing studies. In this study, 204 breeding lines were tested for resistance levels to BCMV and BCMNV. Initially, BCMNV NL-3 and BCMV NL-4 strains were individually sap-inoculated onto the leaves of bean plants belonging to each breeding lines with 10 replications, and the reactions of plants were evaluated for symptomatic appearance of virus infection 21 days after inoculation. Additionally, phenotypic evaluation was confirmed by molecular markers linked to resistance genes. As a result of the study, 153 breeding lines were found to involve the dominant I gene whereas four and five of the tested lines had the recessive genes bc-1² and bc-2², respectively. In conclusion, it was emphasized that these breeding lines could be registered after evaluating them in terms of yield and quality. Also, the use of seeds of the resistant lines to supply the source of virus-resistance in breeding studies and maintaining their seeds at the national genebank were recommended.

Combined Application of Citric Acid and Cr Resistant Microbes Improved Castor Bean Growth and Photosynthesis while it Alleviated Cr Toxicity by Reducing Cr+6 to Cr3+

Chromium is highly harmful to plants because of its detrimental effects on the availability of vital nutrients and secondary metabolites required for proper plant growth and development. A hydroponic experiment was carried out to analyze the effect of citric acid on castor bean plants under chromium stress. Furthermore, the role of two chromium-resistant microorganisms, Bacillus subtilis and Staphylococcus aureus, in reducing Cr toxicity was investigated. Different amounts of chromium (0 µM, 100 µM, 200 µM) and citric acid (0 mM, 2.5 mM, and 5 mM) were used both alone and in combination to analyze the remediation potential. Results showed that elevated amounts of chromium (specifically 200 µM) minimized the growth and biomass because the high concentration of Cr induced the oxidative markers. Exogenous citric acid treatment boosted plant growth and development by improving photosynthesis via enzymes such as superoxide dismutase, guaiacol peroxidase, catalase, and ascorbate peroxidase, which decreased Cr toxicity. The application of citric acid helped the plants to produce a high concentration of antioxidants which countered the oxidants produced due to chromium stress. It revealed that castor bean plants treated with citric acid could offset the stress injuries by decreasing the H2O2, electrolyte leakage, and malondialdehyde levels. The inoculation of plants with bacteria further boosted the plant growth parameters by improving photosynthesis and reducing the chromium-induced toxicity in the plants. The findings demonstrated that the combination of citric acid and metal-resistant bacteria could be a valuable technique for heavy metal remediation and mediating the adverse effects of metal toxicity on plants.

IDENTIFICATION OF Ricinus communis HYBRIDS FOR LOW PLANT HEIGHT1

ABSTRACT Castor bean (Ricinus communis L.) is a plant native to Africa that presents important socioeconomic value for many countries, and has been the subject of breeding programs. In this context, the objective of this work was to identify genotypes with potential for improvement, focused on lowering plant height, using 19 hybrids and eight parents of R. communis. The study was developed at the experimental area of the Federal University of Recôncavo da Bahia in Cruz das Almas, BA, Brazil. The experiment was conducted in 2017 using a randomized block design with three replications, consisting of eight parents and 19 hybrids resulting from hybridization of these parents, grown with spacing of 3 meters between rows and 1 meter between plants. The characters stem diameter (SD), primary raceme insertion height (PRI), number of stem internodes (NSI), mean stem internode length (SIL), plant height (PH), number of harvested racemes (NHR), primary raceme length (PRL), and effective raceme length (ERL) were evaluated by analyzing the genetic parameters of variances and correlation between them. Five (H17, H2, H11, H13, and H6) of the 19 hybrids evaluated have potential to decrease PH of castor bean plants, presenting heights below 1.07 m. Direct selection for plant height is the most indicated for this purpose due to the high heritability of the character. However, the characters SD, PRI, and SIL stood out by assisting in indirect selection to decrease plant height because they can be early measured and present high heritability and strong correlation with PH.

Critical Timing of Weed Removal in Dry Bean as Influenced by the Use of Preemergence Herbicides

The critical timing of weed removal (CTWR) is the point in crop development when weed control must be initiated to prevent crop yield loss due to weed competition. A field study was conducted in 2018 and 2020 near Scottsbluff, NE to determine how the use of preemergence herbicides impacts the CTWR in dry bean. The experiment was arranged as a split-plot, with herbicide treatment and weed removal timing as main and sub plot factors, respectively. Herbicide treatment consisted of no-preemergence, or pendimethalin (1070 g ai ha–1) + dimethenamid-P (790 g ai ha–1) applied preemergence. Sub-plot treatments included season-long weed-free, weed removal at: V1, V3, V6, R2, and R5 dry bean growth stages, and a season-long weedy control. A four-parameter logistic model was used to estimate the impact of time of weed removal, for all response variables including dry bean yield, dry bean plants m–1 row, pods plant–1, seeds pod–1, and seed weight. The CTWR based on 5% yield reduction was estimated to range from the V1 growth stage [(16 d after emergence (DAE)] to the R1 growth stage (39 DAE) in the no-PRE herbicide treatment. In the PRE-applied treatment, the CTWR began at the R2 growth stage (47 DAE). Dry bean plants m–1 row was reduced in the no-preemergence treatment when weed removal was delayed beyond the R2 growth stage in the 2020 field season. The use of preemergence-applied herbicides prevented a reduction in the number of pods plant–1 in 2020, and the number of seeds pod–1 in 2018 and 2020. In 2018, the number of pods plant–1 was reduced by 73% when no-preemergence was applied, compared to 26% in the preemergence-applied treatment. The use of preemergence-applied soil active herbicides in dry bean delayed the CTWR and preserved yield potential.

Genomic Characterization of a New Enamovirus Infecting Common Bean

A novel enamovirus was identified from bean plants with disease symptoms. Its genome of 5,781 nucleotides (nt) encodes five open reading frames. The virus and other species of the genus Enamovirus share identities of 50.4%-68.4% at the complete genome, and 19.9%-51.9% of P0, 24.9%-52.5% of P1, 33.4%-62.9% of P1-P2, 30.6%-81.1% of P3, 32.3%-74.2% of P3-P5 at amino acid sequence level, respectively. Phylogenetic analysis showed that the virus is most closely related to Alfalfa enamovirus 1 and Pea enation mosaic virus 1 in the genus Enamovirus within family Solemoviridae. These results suggest that the virus should be considered as a novel species in the genus Enamovirus and tentatively named as “bean enamovirus 1”.