Abstract Jackfruit (Artocarpus heterophyllus Lam.) is a fruit of tropical and subtropical zones of the world, is an important source of phytochemicals (phenolic acids, flavonoids and tannins). Several studies have associated phytochemicals with antioxidant and antimicrobial properties. The objective of this work was to analyze the polyphenolic content, the antioxidant and antifungal properties of jackfruit extracts on phytopathogenic fungi. Two phenolic extracts of jackfruit of different maturity level (J1-J2) were used. The total polyphenol content (TPC) was determined by Folin-Ciocalteu method and total flavonoids (TFC) by the aluminum chloride method, the free radical trapping potential was measured using FRAP and ORAC methods. The results showed a TPC of 844 and 1,178 mgEAG/100 g and TFC of 37 and 68 mgQE/100 g, of dry jackfruit, the antioxidant potential analysis by FRAP was 7,575 and 8,691, by ORAC was 13.369 and 14.728 µmol Trolox/100 g, of dry jackfruit for J1 and J2 respectively. Additionally, it was observed that the phenolic extracts of jackfruit reduced the mycelial growth of: Penicillium digitatum (20-14%), Geotrichum candidum (56-55%), Aspergillus niger (72-67%) and Botrytis cinerea (100%-100%) for J1 and J2 respectively. We conclude that regardless of the degree of maturity, jackfruit has antioxidant and antifungal properties on phytopathogens important in agriculture.

Charcoal rot caused by Macrophomina phaseolina is an important disease of sugarcane in Mexico. This study was carried out to characterize isolates of M. phaseolina obtained from sugarcane by the combination of morphological and molecular analyses. The morphological characterization of 10 isolates was performed using scanning electron microscopy and light microscopy. To confirm the morphological identification, rDNA from two representative isolates was extracted, and the internal transcribed spacer (ITS) region was amplified by polymerase chain reaction and sequenced using specific primers MpKF1 and MpKR1. Based on their morphological characteristics, all isolates were identified as M. phaseolina. Moreover, the analysis of two ITS sequences showed 100 % similarity with the M. phaseolina sequences deposited in the GenBank. To our knowledge, this is the first study in the world aimed at characterizing isolates of M. phaseolina obtained from sugarcane.

La pudrición carbonosa, causada por Macrophomina phaseolina, es una enfermedad importante de la caña de azúcar en México. Este estudio se realizó con el objetivo de caracterizar aislados de M. phaseolina obtenidos de caña de azúcar mediante análisis morfológicos y moleculares. La caracterización morfológica de 10 aislados se llevó a cabo con el uso de microscopia electrónica de barrido y microscopia de luz. Para confirmar la identificación, se extrajo el ADNr de 2 aislados representativos, y la región del espaciador interno transcrito (ITS) se amplificó mediante la reacción en cadena de la polimerasa y se secuenció usando los iniciadores específicos MpKF1 y MpKR1. Los aislados se identificaron como M. phaseolina con base en la morfología. El análisis de secuencias ITS mostró 100 % de similitud con las secuencias de M. phaseolina depositadas en el GenBank. Para nuestro conocimiento, este es el primer estudio del mundo enfocado a caracterizar aislados de M. phaseolina obtenidos de caña de azúcar.

Introgresión del tamaño de la gluma y la cobertura del grano en poblaciones de sorgo. El objetivo de esta investigación fue determinar si la introgresión de líneas exóticas de sorgo incrementa la variabilidad del tamaño de la gluma y el porcentaje de grano descubierto. La población NESC7 (P1) se formó durante cuatro ciclos agrícolas (2005-2007), con un ciclo de introgresión, y a partir del quinto ciclo agrícola (2008) se estimó la variabilidad genética del caracter a través de 120 familias de medios hermanos y 110 familias de autohermanos. Se utilizó la metodología de Bloques Incompletos en dos localidades, Facultad de Agronomía de la Universidad Autónoma de Nuevo León (FAUANL) en Marín Nuevo León y el INIFAP en Río Bravo, Tamaulipas. La introgresión de líneas exóticas con menor tamaño de gluma y cobertura de grano en la población NESC7 (P1), mostró una disminución del tamaño de la gluma (13%), un incremento del porcentaje de grano descubierto (28%), y una mayor proporción de ambas características de la varianza aditiva (5% y 1%), heredabilidad en sentido estrecho de 22% y de 1% y mayor respuesta a la selección (4% y 0,3%).

Introgression of glum size and grain cover into sorghum populations. The objective of the study was to determine if the introgression of exotic sorghum lines increases the variability in the size of the glum and in the percent of uncovered grains. The sorghum population NESC7 (P1) was formed during four agricultural cycles (2005-2007) with an introgression cycle, and beginning on the fifth agricultural cycle (2008), the genetic variability for these traits was estimated in the 120 half-silb and 110 selfsib families. The methodology of incomplete block design was used at two locations, the Faculty of Agronomy at the University of Nuevo Leon (FAUANL) in Marín Nuevo Leon and INIFAP in Río Bravo, Tamaulipas. The introgression of exotic lines with smaller glum size and reduced grain cover into the population NESC7 (P1) reduced the size of the (13%), increased the percentage of uncovered grain (28%), and increased the proportion of both characteristics in the additive variance (5% and 1%), the heritability in a narrow sense of 22 % and 1% and higher response to selection (4% y 0.3%).