RESUMEN

Soursop (Annona muricata L.) is climacteric fruit with a short ripening period and postharvest shelf life, leading to a rapid softening. In this study, transcriptome analysis of soursop fruits was performed to identify key gene families involved in ripening under postharvest storage conditions (Day 0, Day 3 stored at 28 ± 2 °C, Day 6 at 28 ± 2 °C, Day 3 at 15 ± 2 °C, Day 6 at 15 ± 2 °C, Day 9 at 15 ± 2 °C). The transcriptome analysis showed 224,074 transcripts assembled clustering into 95, 832 unigenes, of which 21, 494 had ORF. RNA-seq analysis showed the highest number of differentially expressed genes on Day 9 at 15 ± 2 °C with 9291 genes (4772 up-regulated and 4519 down-regulated), recording the highest logarithmic fold change in pectin-related genes. Enrichment analysis presented significantly represented GO terms and KEGG pathways associated with molecular function, metabolic process, catalytic activity, biological process terms, as well as biosynthesis of secondary metabolites, plant hormone signal, starch, and sucrose metabolism, plant-pathogen interaction, plant-hormone signal transduction, and MAPK-signaling pathways, among others. Network analysis revealed that pectinesterase genes directly regulate the loss of firmness in fruits stored at 15 ± 2 °C.

RESUMEN

RESUMEN La guanábana (Annona muricata L.) es un cultivo de importancia económica para Nayarit, México. Los frutos han tenido una excelente aceptación en el mercado regional, dificultando su comercialización a lugares lejanos porque la producción es altamente perecedera, aunado a que los árboles de los huertos de guanábana son en su mayoría ecotipos o fenotipos sin ningún plan de mejoramiento genético. Debido a la falta de variedades comerciales y de un banco de germoplasma, es importante conocer la diversidad genética para identificar y seleccionar genotipos; una de las herramientas para este propósito es el uso de marcadores moleculares. El objetivo de esta investigación fue analizar la diversidad genética de guanábana de las principales zonas productoras de Nayarit. Se extrajo ADN genómico de hojas de guanábana, las cuales fueron recolectadas de 11 huertos (poblaciones) de las siguientes zonas: Compostela (cinco poblaciones), Tepic (tres poblaciones) y San Blas (tres poblaciones). Posteriormente, se realizó un análisis mediante marcadores moleculares SSR y SRAP. Los resultados indicaron que los SSR no mostraron polimorfismo entre las poblaciones. Por otro lado, en los marcadores SRAP se obtuvieron 116 loci polimórficos con un promedio de porcentaje de loci polimórfico (P) entre las zonas productoras de 29,55 %. Asimismo, se realizó un AMOVA, el cual mostró que el mayor porcentaje de varianza se encuentra dentro de las poblaciones. Además, los análisis de agrupamiento demostraron la formación de tres grupos independientes. Por tanto, se obtuvo una alta homocigocidad y baja diversidad genética de guanábana entre las zonas y poblaciones estudiadas.

ABSTRACT Soursop (Annona muricata L.) is a crop of economic importance for Nayarit, Mexico. Soursop fruits have had an excellent acceptance in the regional market, making it difficult its commercialization to distant places because the production is highly perishable, in addition to the fact that the trees in the soursop orchards are mostly ecotypes or phenotypes without any genetic improvement plan. Due to the lack of commercial varieties and a germplasm bank, it is important to know the genetic diversity to identify and select genotypes; one of the tools for this purpose is the use of molecular markers. The objective of this research was to analyze the genetic diversity of soursop in the main producing areas of Nayarit. Genomic DNA was extracted from soursop leaves from 11 orchards (populations) in the following areas: Compostela (five populations), Tepic (three populations) and San Blas (three populations). Subsequently, we performed molecular analysis using SSR and SRAP molecular markers. The results indicated that the SSRs showed no polymorphism between the populations. On the other hand, we found 116 polymorphic loci in the SRAP markers with an average percentage of polymorphic loci (P) among the producing areas of 29.55 %. Likewise, an AMOVA was performed, showing that the highest percentage of variance is found within the populations. Furthermore, cluster analyzes demonstrated the formation of three independent groups. Therefore, a high homozygosity and low genetic diversity of soursop were obtained between the areas and populations studied.

RESUMEN

Soursop leaves are a source of phytochemical compounds, such as phenolic acids, flavonoids, hydrolyzable tannins, and acetogenins. These compounds can have several types of biological activities. Lactic acid bacteria can uptake phenolic compounds present in plants or fruits. The aim of the present work was to investigate the in vitro effect of hexane, acetone, methanolic, and aqueous extracts of soursop leaves (Annona muricata L.) on the growth, motility, and biofilm formation of Lactobacillus casei, and to determine compounds related to growth. The minimum concentration promoting growth, motility (swimming, swarming, and twitching), and biofilm-forming capacity (crystal violet) were evaluated. The results showed the growth-promoting capacity of acetone and aqueous extracts at low doses 25-50 mg/L, and an inhibition in the four extracts at higher doses of 100 mg/L. The L. casei growth is related to ellagic acid, quercetin rhamnoside, kaempferol dihexoside, quercetin hexoside, secoisolariciresinol, and kaempferol hexoside-rhamnoside. Hexane extract increased the three types of motility, while aqueous maintained swimming and twitching motility similar to control. The four extracts inhibited the biofilm formation capacity.