Biotechnological Strategies Adopted for Sugarcane Disease Management in Tucumán, Argentina.

Sugarcane diseases can be controlled by an integrated management approach where biotechnological tools can successfully contribute. The Obispo Colombres Agroindustrial Experimental Station (EEAOC) in Tucumán (Argentina's main sugarcane producer) has successfully implemented multiple strategies that greatly enhance the productivity of sugarcane fields. The local breeding program develops resistant varieties by applying molecular markers to reveal the presence of gene for brown rust resistance throughout the EEAOC germplasm collection.

Genotypic and phenotypic characterization of industrial autochthonous Saccharomyces cerevisiae for the selection of well-adapted bioethanol-producing strains.

In northwestern Argentina, sugarcane-derived industrial fermentation is being extensively used for bioethanol production, where highly adaptive native strains compete with the baker's yeast Saccharomyces cerevisiae traditionally used as starter culture. Yeast populations of 10 distilleries from Tucumán (Argentina) were genotypic and phenotypic characterized to select well-adapted bioethanol-producing autochthonous strains to be used as starter cultures for the industrial production of bioethanol fuel. From the 192 isolates, 69.

A brassinosteroid functional analogue increases soybean drought resilience.

Drought severely affects soybean productivity, challenging breeding/management strategies to increase crop resilience. Hormone-based biostimulants like brassinosteroids (BRs) modulate growth/defence trade-off, mitigating yield losses; yet, natural molecule's low stability challenges the development of cost-effective and long-lasting analogues. Here, we investigated for the first time the effects of BR functional analogue DI-31 in soybean physiology under drought by assessing changes in growth, photosynthesis, water relations, antioxidant metabolism, nodulation, and nitrogen homeostasis.

Selecting putative drought-tolerance markers in two contrasting soybeans.

Identifying high-yield genotypes under low water availability is essential for soybean climate-smart breeding. However, a major bottleneck lies in phenotyping, particularly in selecting cost-efficient markers associated with stress tolerance and yield stabilization. Here, we conducted in-depth phenotyping experiments in two soybean genotypes with contrasting drought tolerance, MUNASQA (tolerant) and TJ2049 (susceptible), to better understand soybean stress physiology and identify/statistically validate drought-tolerance and yield-stabilization traits as potential breeding markers.

Genetic Transformation of Sugarcane, Current Status and Future Prospects.

Sugarcane ( spp.) is a tropical and sub-tropical, vegetative-propagated crop that contributes to approximately 80% of the sugar and 40% of the world's biofuel production. Modern sugarcane cultivars are highly polyploid and aneuploid hybrids with extremely large genomes (>10 Gigabases), that have originated from artificial crosses between the two species, and .

Seasonal Variation of Plant Defense Inductor Ellagitannins in Strawberry Leaves under Field Conditions for Phytosanitary Technological Applications.

Many natural compounds can activate the plant immunity, and for this reason, they have attracted special interest in crop disease management. Previously, we isolated from strawberry leaves an ellagitannin (HeT), which elicits plant defense responses. In this research, we investigated bioactive compounds from field-collected strawberry leaves capable of inducing defense responses in against a bacterial pathogen.

Strawberry fatty acyl glycosides enhance disease protection, have antibiotic activity and stimulate plant growth.

An increasing interest in the development of products of natural origin for crop disease and pest control has emerged in the last decade. Here we introduce a new family of strawberry acyl glycosides (SAGs) formed by a trisaccharide (GalNAc-GalNAc-Glc) and a monounsaturated fatty acid of 6 to 12 carbon atoms linked to the glucose unit. Application of SAGs to Arabidopsis thaliana (hereafter Arabidopsis) plants triggered a transient oxidative burst, callose deposition and defense gene expression, accompanied by increased protection against two phytopathogens, Pseudomonas viridiflava and Botrytis cinerea.

The histone-like protein HupB influences biofilm formation and virulence in Xanthomonas citri ssp. citri through the regulation of flagellar biosynthesis.

Citrus canker is an important disease of citrus, whose causal agent is the bacterium Xanthomonas citri ssp. citri (Xcc). In previous studies, we found a group of Xcc mutants, generated by the insertion of the Tn5 transposon, which showed impaired ability to attach to an abiotic substrate.

Development of PSP1, a Biostimulant Based on the Elicitor AsES for Disease Management in Monocot and Dicot Crops.

In this work, we present a novel biostimulant for sustainable crop disease management, PSP1, based on the plant defense-elicitor AsES, an extracellular protease produced by the strawberry fungal pathogen . Fungal fermentation conditions and downstream processing were determined to maximize extracellular protein production, product stability and a high plant defense-eliciting activity, as monitored by anthracnose resistance in supernatant-treated strawberry plants subsequently infected with a virulent strain of . Fermentation batches were shown to reduce anthracnose development by 30-60% as compared to infected non-treated plants.

The Endophytic Strain Kd70 Lacks Pathogenic Island-Like Regions in Its Genome and Is Incapable of Infecting the Urinary Tract in Mice.

spp. have been isolated from many different environmental habitats but have mainly been associated with nosocomial acquired diseases in humans. Although there are many recently published sequenced genomes of members of this genus, there are very few studies on whole genome comparisons between clinical and non-clinical isolates, and it is therefore still an open question if a strain found in nature is capable of infecting humans/animals.

Soybean-Macrophomina phaseolina-Specific Interactions and Identification of a Novel Source of Resistance.

Charcoal rot, caused by the fungus Macrophomina phaseolina, is an economically important disease of soybean (Glycine max) worldwide. Objectives of the present research were to (i) study the genetic and pathogenic diversity in a collection of M. phaseolina isolates from Argentina and Paraguay and (ii) develop an improved in vitro phenotyping method to evaluate disease response of soybean genotypes to M.

Elicitor-Based Biostimulant PSP1 Protects Soybean Against Late Season Diseases in Field Trials.

Currently, fungicide application in soybean production accounts for an important amount of global pesticide use, and it is therefore most desirable to find new healthier and more environmental friendly alternatives for the phytosanitary management in this crop. In this study, we present convincing evidence for effective induction of disease protection by the agricultural biostimulant PSP1, a formulation based on the plant-defense eliciting activity of the fungal protease AsES ( elicitor subtilisin), in multiple field trials in Argentina. PSP1 was shown to combine well with commercial spray adjuvants, an insecticide, a herbicide and fungicides used in Argentinian soybean production without losing any defense-inducing activity, indicating an easy and efficient adaptability to conventional soybean production and disease management in the region.

Ellagitannin HeT obtained from strawberry leaves is oxidized by bacterial membranes and inhibits the respiratory chain.

Plant secondary metabolism produces a variety of tannins that have a wide range of biological activities, including activation of plant defenses and antimicrobial, anti-inflammatory and antitumoral effects. The ellagitannin HeT (1--galloyl-2,3;4,6-bis-hexahydroxydiphenoyl-β-d-glucopyranose) from strawberry leaves elicits a strong plant defense response, and exhibits antimicrobial activity associated to the inhibition of the oxygen consumption, but its mechanism of action is unknown. In this paper we investigate the influence of HeT on bacterial cell membrane integrity and its effect on respiration.

The ellagitannin HeT induces electrolyte leakage, calcium influx and the accumulation of nitric oxide and hydrogen peroxide in strawberry.

HeT (1-0-galloyl-2,3; 4,6-bis-hexahydroxydiphenoyl-β-D-glucopyranose) is a penta-esterified ellagitannin obtained from strawberry leaves. Previous studies have shown that foliar application of HeT prior to inoculation with a virulent pathogen increases the resistance toward Colletotrichum acutatum in strawberry plants and to Xanthomonas citri subsp. citri in lemon plants.

Biological characterization and mating compatibility of Helicoverpa gelotopoeon (D.) (Lepidoptera: Noctuidae) populations from different regions in Argentina.

Helicoverpa gelotopoeon, the South American bollworm, is a polyphagous pest of the Heliothinae complex that causes damage to soybean, cotton, and chickpea crops. Some species within this complex have developed resistance to genetically modified crops and insecticides, which has led to increased interest in their genetic diversity and population structure. The objective of this study was to characterize biological and reproductive parameters of two populations of H.

The Elicitor Protein AsES Induces a Systemic Acquired Resistance Response Accompanied by Systemic Microbursts and Micro-Hypersensitive Responses in Fragaria ananassa.

The elicitor AsES (Acremonium strictum elicitor subtilisin) is a 34-kDa subtilisin-like protein secreted by the opportunistic fungus Acremonium strictum. AsES activates innate immunity and confers resistance against anthracnose and gray mold diseases in strawberry plants (Fragaria × ananassa Duch.) and the last disease also in Arabidopsis.

Inducible expression of Bs2 R gene from Capsicum chacoense in sweet orange (Citrus sinensis L. Osbeck) confers enhanced resistance to citrus canker disease.

Transgenic expression of the pepper Bs2 gene confers resistance to Xanthomonas campestris pv. vesicatoria (Xcv) pathogenic strains which contain the avrBs2 avirulence gene in susceptible pepper and tomato varieties. The avrBs2 gene is highly conserved among members of the Xanthomonas genus, and the avrBs2 of Xcv shares 96% homology with the avrBs2 of Xanthomonas citri subsp.

Resistance to citrus canker induced by a variant of Xanthomonas citri ssp. citri is associated with a hypersensitive cell death response involving autophagy-associated vacuolar processes.

Xanthomonas citri ssp. citri (X. citri) is the causal agent of Asiatic citrus canker, a disease that seriously affects most commercially important Citrus species worldwide.

A modified indirect mathematical model for evaluation of ethanol production efficiency in industrial-scale continuous fermentation processes.

Aims: To calculate fermentation efficiency in a continuous ethanol production process, we aimed to develop a robust mathematical method based on the analysis of metabolic by-product formation.

Methods And Results: This method is in contrast to the traditional way of calculating ethanol fermentation efficiency, where the ratio between the ethanol produced and the sugar consumed is expressed as a percentage of the theoretical conversion yield. Comparison between the two methods, at industrial scale and in sensitivity studies, showed that the indirect method was more robust and gave slightly higher fermentation efficiency values, although fermentation efficiency of the industrial process was found to be low (~75%).

Reproductive isolation between two populations of Diatraea saccharalis (F.) (Lepidoptera: Crambidae) from different host plant species and regions in Argentina.

The sugarcane borer, Diatraea saccharalis (F.), has a widespread distribution throughout the Western Hemisphere and is a pest of many crop plants including sugarcane, corn, sorghum and rice. The use of Bacillus thuringiensis (Bt) corn has been the primary tool for managing this species in corn fields.

Isolation of cellulolytic bacteria from the intestine of Diatraea saccharalis larvae and evaluation of their capacity to degrade sugarcane biomass.

As a strategy to find efficient lignocellulose degrading enzymes/microorganisms for sugarcane biomass pretreatment purposes, 118 culturable bacterial strains were isolated from intestines of sugarcane-fed larvae of the moth Diatraea saccharalis. All strains were tested for cellulolytic activity using soluble carboxymethyl cellulose (CMC) degrading assays or by growing bacteria on sugarcane biomass as sole carbon sources. Out of the 118 strains isolated thirty eight were found to possess cellulose degrading activity and phylogenetic studies of the 16S rDNA sequence revealed that all cellulolytic strains belonged to the phyla γ-Proteobacteria, Actinobacteria and Firmicutes.

XbmR, a new transcription factor involved in the regulation of chemotaxis, biofilm formation and virulence in Xanthomonas citri subsp. citri.

Xanthomonas citri subsp. citri (Xcc) is the causal agent of citrus canker. Biofilm formation on citrus leaves plays an important role in epiphytic survival of Xcc.

Genome-wide annotation of the soybean WRKY family and functional characterization of genes involved in response to Phakopsora pachyrhizi infection.

Background: Many previous studies have shown that soybean WRKY transcription factors are involved in the plant response to biotic and abiotic stresses. Phakopsora pachyrhizi is the causal agent of Asian Soybean Rust, one of the most important soybean diseases. There are evidences that WRKYs are involved in the resistance of some soybean genotypes against that fungus.

A Study of the Sugarcane Yellow Leaf Disease in Argentina.

Yellow leaf disease, caused by Sugarcane yellow leaf virus (SCYLV), is widespread around the world but very little information is available on this viral disease in Argentina. Therefore, the aims of the study were to assess the presence of SCYLV, analyze its distribution in the main sugarcane production areas of Argentina, characterize the virus, and determine histological alterations caused by its presence. For this purpose, 148 sugarcane samples with and without symptoms were collected in 2011 and 2012 from the province of Tucumán.