ABSTRACT
Background The genetic diversity and structure of 31 popcorn accessions of the germplasm bank of the State University of Maringá were assessed using 30 microsatellite primers. Results 127 alleles were identified from 30 evaluated loci. The number of alleles per locus ranged from two to eight. The overall mean of the polymorphic loci averaged 79.89%. The primers UMC1549 and UMC1072 detected polymorphism in all accessions analyzed. The mean observed heterozygosity ranged from 0.07 to 0.30 and the highest proportion of heterozygous plants was observed in accession BOZM 260 (Ho = 0.30). The analysis of molecular variance revealed that 60% of the total genetic variation was found within accessions and 40% was found between accessions. The Bayesian clustering approach grouped the 31 accessions into two genetically differentiated clusters. The dendrogram revealed that accessions TATU 2 and ARZM 05 083 are genetically less similar than the others. Conclusions The analysis allowed to identify microsatellite loci with high levels of heterozygosity (UMC1549 and UMC1072). These loci can be indicated as promising for detecting polymorphisms in popcorn accessions and in the monitoring of genetic improvement programs. Moreover, allowed to identify heterozygous accessions (BOZM 260), this accession showed allelic variation at all analyzed microsatellite loci and can be recommended for crosses with plants that have desirable agronomic characteristics, with a view to the broadening of the genetic base of popcorn accessions and developing new cultivars.
Subject(s)
Genetic Variation , Genetic Markers , Microsatellite Repeats , Zea mays/genetics , Brazil , Alleles , Seed Bank , HeterozygoteABSTRACT
The genetic variability of Atta sexdens rubropilosa leaf-cutting ants collected from five brazilian localities was evaluated with PCR-RAPD technique. We used 15 primers producing 148 fragments of which 123 (83.11 %) contained polymorphisms. The estimated Shannon index was 0.3836 ± 0.2335 showing that these ants possess high genetic diversity. The G ST value was 0.2372 and ΦPT = 0.184, indicating that the analyzed populations are moderately differentiated and 82 % of the variation obtained occur within populations. Although Mantel's test had shown correlation between genetic distances and geographic was observed that Ivatuba and Itambé (33.8 km) have the small geographical distance and the largest genetic distance. The lower genetic distance was estimated for Maringá and Ivatuba but this localities have a small geographic distance (42.3 km), indicating that there are no barriers for mating among reproducers in these populations. The high degree of polymorphism (83.11 %) and the ability to cross among the populations in the studied regions indicate that this species of leaf-cutting ant is well adapted to the region; therefore, integrated control programs can be developed.
La variabilidad genética de las hormigas Atta sexdens rubropilosa colectadas en cinco lugares distintos de Brasil fueron evaluados por la técnica PCR-RAPD. Un total de 15 primers produjeron 148 fragmentos, de los cuales 123 fueron polimórficos, lo que corresponden al 83,11 %. La estimación de la diversidad genética por el índice de Shannon fue 0,3836 y el desviación estándar fue de ± 0,2335. Estos valores demuestran una alta diversidad genética. El valor de G ST fue 0,2372 y ΦPT = 0,184 lo que indica que las poblaciones están moderadamente diferenciadas y que el 82 % de la variación obtenida se produce dentro de las poblaciones. Aunque la prueba de Mantel ha demostrado una correlación entre la distancia genética y geográfica se observó que Ivatuba e Itambé (33,8 km) tiene una pequeña distancia geográfica y la mayor distancia genética. La distancia inferior genética fue estimada para Maringá e Ivatuba pero estas localidades cuentan con una distancia geográfica pequeña (42,3 km), lo que indica que no hay barreras para el apareamiento entre los reproductores en estas poblaciones. El alto valor de polimorfismo (83,11 %) y la capacidad de emparejamiento entre las poblaciones presentes en las regiones estudiadas, indican que esta especie de hormiga cortadora está bien adaptada a la región, y deben ser desarrollados programas integrados de control si se convierten en plagas.
ABSTRACT
The production of alkaloids from Cereus peruvianus callus cultured in medium supplemented with different tyrosine concentrations, different 2,4-D/kinetin levels, and with NaCl was investigated using long-term callus culture. - and -Esterase isozyme patterns were also analyzed to investigate the differential gene expression in callus subcultured with the different tyrosine concentrations. The greatest amounts of alkaloids were obtained from callus maintained in medium containing 200 mg/L of tyrosine. Tyrosine induced a differential gene expression for the synthesis of specific - and -esterase isozymes. Two -carboxylesterases (EC 3.1.1.1) and one /-arylesterase (EC 3.1.1.2) were induced in callus, one /-acetylesterase (EC 3.1.1.6) and two -carboxylesterase were detected as more intensely stained while two /-carboxylesterases were absent or detected as more weakly stained bands after the addition of tyrosine as precursor
Tecidos de calos em cultura prolongada de Cereus peruvianus foram utilizados para investigar a produção de alcalóides pelos calos quando mantidos em meio de cultura suplementados com diferentes concentrações de tirosina, com diferentes níveis de 2,4-D/cinetina, e contendo NaCl. Foi analisado também, o padrão de isozimas - e -esterases, para investigar a expressão diferencial de genes nos calos subcultivados com as diferentes concentrações de tirosina. A maior quantidade de alcalóides foi obtida a partir de calos mantidos em meio contendo 200 mg/L de tirosina. A adição de tirosina no meio induziu uma expressão gênica diferencial para a síntese de isozimas - e -esterases. Duas -carboxilesterases (EC 3.1.1.1) e uma /-arilesterase (EC 3.1.1.2) foram induzidas nos calos, uma /-acetilesterase (EC 3.1.1.6) e uma -carboxilesterase foram detectadas como bandas mais intensamente coradas, enquanto duas /-carboxilesterases não foram detectadas ou foram fracamente coradas após a adição de tirosina como precursor no meio de cultura