Use of Actinobacteria Streptomyces griseocarneus for the Control of Fusarium solani Fungus in Passion Fruit Crops

In passion fruit crops, species of the Fusarium solani fungal complex acts as causal agents of collar rot. The symptoms of this disease are characterized by sudden wilting, collapse, and plant death at any stage of development. One of the possible measures to reduce the environmental risk of intensive cultivation is the use of biological controls, which can be found in the form of endophytic microorganisms. In view of this, the present study investigates the use of the endophytic actinobacterium Streptomyces griseocarneus, isolate R132, to promote in vitro and in vivo biological control of F. solani isolates in passion fruit seedlings. Two experiments were conducted: 1) The antibiosis assay in paired culture was used to quantify the antagonism between the actinobacterium S. griseocarneus R132 and eight isolates of the Fusarium solani species complex. 2) The ability of S. griseocarneus, isolate R132, to control seven isolates of F. solani was tested. In the present study, the in vitro antifungal potential of S. griseocarneus R132 was observed against all F. solani isolates. In the biological control evaluation, the actinobacterium significantly reduced the disease damage compared to untreated plants, suggesting that this bacterium is a potential biological control agent

SUSCEPTIBILITY TO WATER EROSION OF SOILS FROM THE MUNICIPALITY SALTO DO CÉU, SW MATO GROSSO STATE, BRAZIL - BRASIL

The evaluation of the potential for soil erosion may assist in the identification and recovery of degraded areas. The aim of this study was to evaluate the potential for soil erosion in the municipality of Salto do Céu, seeking proper planning of land use. In this area, a geomorphologic and soil type subdivision were made. A map on erosion potential was generated, associating the soil maps with erosion potential classes. These classes and the topographic factor originated a map of susceptibility to erosion. The erosion potential map was obtained matching the erosion susceptibility map with the capacity of land use from the area under study. Conflicts arose from the maps of potential erosion and usability. 59.57% of Salto do Céu area consists of Ultisols. In this municipality, 23.41% of its area has very high erosion potential, 67.80% medium erosion potential and 8.79% low erosion potential. Areas with high potential are composed of Entisols and Ultisols (Nitisols). The sites with high potential for water erosion are being used inadequately. In almost the entire municipality there are conflicts among the current land use and the real capacity to support the actual us

Reassessing the genetic variability of Tectona grandis through high-throughput genotyping: Insights on its narrow genetic base.

Teak (Tectona grandis Linn. f.) is considered one of the most expensive hardwoods in the world. The dispersion of the species over the years has taken the teak beyond its first sources of diversity and little is known about the genetic origin and genetic variability. Thus, this study aimed to investigate the genetic diversity and genetic population structure existing in a representative teak germplasm bank collection. DNA was extracted from young leaves and each sample were genotyped by whole genome sequencing at 3 giga bases per sample, the sequences are aligned using the genome, and SNPcalls and quality control were made. To study the population structure of the genotypes, Bayesian variational inference was used via fastStructure, the phylogenetic tree was based on the modified Euclidean distance and the clustering by the UPGMA hierarchical method. Genetic diversity was analyzed based on the pairwise genetic divergence (Fst) of Weir and Cockerham. Genotyping by sequencing resulted in a database of approximately 1.4 million of variations SNPs were used for analysis. It was possible to identify four populations with considerable genetic variability between and within them. While the genetic variability in teak is generally known to be narrow, this study confirmed the presence of genetic variability scale in teak, which is contrary to what was initially expected