Adriana Gutiérrez-Díez

ETIQUETAS DE SECUENCIAS EXPRESADAS DIFERENCIALES DE FRUTOS DE AGUACATE RAZA MEXICANA (Persea americana Mill. var. drymifolia)

In this study, Differential Expressed Sequence Tags (ESTs) of immature fruits of Persea americana Mill var. drymifolia of the state of Nuevo León, Mexico were developed and identified. Ten genotypes with fruits of different size and shape were selected to generate ESTs by the differential display technique. In total, 393 amplified differential fragments were obtained, 82 fragments were sequenced and edited for identification and comparison with NCBI nucleotide and protein databases. Forty sequences showed significant similarity to mRNA sequences and / or sequences of hypothetical or predicted proteins belonging to P. americana and / or other genera. Some sequences were related to enzymes such as flavanone-3-hydroxylase (F3H), lecithin-cholesterol acyltransferase, glutathione-S-transferase microsomal and pleiotropic drug resistance protein. With the information of the nucleotide composition of ESTs, primers could be designed to quantify expression levels by real-time RT-PCR of genes in different phenological stages of the fruit and to make comparisons among genotypes that allow determining alternative uses of their fruits.

Genetic Diversity of Mexican Avocado in Nuevo Leon, Mexico

Mexico is considered the center of origin of avocado, and in the mountains of Sierra Madre Oriental in Nuevo Leon the remains of an avocado have been found, which are evidence of the place or origin of Persea americana var. drymifolia, or the Mexican avocado. Wild creoles have been found growing with native vegetation and have contrasting characteristics with cultivated varieties (improved creoles) and creoles (seedling) found in orchards. All this diversity represents a valuable source of genes and genetic combinations that can be used in Persea breeding programs. Therefore, we performed studies in the north and south areas of Nuevo Leon, Mexico, in order to determine the genetic diversity of this crop and implement actions for the characterization and conservation of this genetic resource, which has been disappearing due to changes in soil use, the introduction of improved varieties and the destruction of their habitat.

Gut Enzymes from Cactus Weevil (Cactophagus spinolae, Gyllenhal Coleoptera: Curculionidae) Fed Natural Diet

Abstract. Indian fig opuntia, Opuntia ficus-indica (L.) Mill., is a cultivated cactus adapted to semiarid conditions that has established complex interactions with insects. Several insect pests feed on and cause economic damage to the crop. The cactus weevil, Cactophagus spinolae Gyllenhal, is a phytophagous beetle that during larval and adult stages feeds on Opuntia plants, despite defensive compounds -- reported as antinutritional factors -- in the plants. Most likely the insect has developed metabolic mechanisms that enable it to use Opuntia cladodes as food, despite antinutritional factors in the plant. The aim of this work was to determine enzymes as auxiliary elements in the digestive process of the insect. The digestive enzymatic profile was described by zymographic techniques, hydrolysis of synthetic substrates, and chemical-specific inhibitors. Amylase activity was detected, represented by only one band of 80 kDa at pH 7. Serine proteinases dependent of calcium as cofactor were active at pH 8 and 9. Cysteine proteinases were active at pH 5 and 6 and found to be part of the proteolytic battery. Assays with specific substrates allowed detection of trypsin, chymotrypsin, and elastase-like proteinase activities, with 694, 1016, and 891 proteolytic activity units per milligram of protein, respectively. An attenuation effect in the activities of proteinases was detected when interacting with a protein crude extract obtained from the cladode of Indian fig opuntia, showing inhibition of the insect serine proteinases and increased cysteine proteinase activities. Interaction between plants and specialist insects is complex, and knowledge of the relationship between Opuntia plants and the insects that attack them, could be an interesting model to understand how strong the interaction is with specialist phytophagous and potentially useful to develop pest management strategies.

COMPORTAMIENTO AGRONÓMICO DE LÍNEAS PARA LA PRODUCCIÓN DE SEMILLA DE SORGO

The objective of the study was to evaluate the agronomic performance of A, B isogenic lines and R grain sorghum lines which restore androfertility of sorghum for grain production. This work was performed during the spring-summer 2010 in Marin Nuevo Leon under drip irrigation. Days to flowering, seed yield per plant, brix degrees and weight of 1000 seeds were measured. The statistical analysis with the benchmark test of averages with independent samples was realized in A, B sorghum lines to days to flowering, seed yield per plant, brix degrees and weight of 1000 seeds. In R lines the analysis of variance and DMS (P<0.05%) test was performed. A an B lines were not completely isogenic; there are A and R lines that may be crossed to produce commercial sorghum grain seed. B and R lines might be used as varieties and A, R parental lines planting splits were defined to produce hybrid sorghum seed.

Agronomic performance of sorghum seed production lines.

The objective of the study was to evaluate the agronomic performance of A, B isogenic lines and R grain sorghum lines which restore androfertility of sorghum for grain production. This work was performed during the spring-summer 2010 in Marin Nuevo Leon under drip irrigation. Days to flowering, seed yield per plant, brix degrees and weight of 1000 seeds were measured. The statistical analysis with the benchmark test of averages with independent samples was realized in A, B sorghum lines to days to flowering, seed yield per plant, brix degrees and weight of 1000 seeds. In R lines the analysis of variance and DMS (P<0.05%) test was performed. A an B lines were not completely isogenic; there are A and R lines that may be crossed to produce commercial sorghum grain seed. B and R lines might be used as varieties and A, R parental lines planting splits were defined to produce hybrid sorghum seed.