Browsing by Author "Caligari, Peter D. S."

Now showing 1 - 7 of 7
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    Application of inter-simple sequence repeats relative to simple sequence repeats as a molecular marker system for indexing blueberry cultivars
    (2013) Garriga, Miguel; Parra, Pablo A.; Caligari, Peter D. S.; Retamales, Jorge B.; Carrasco Gálvez, Basilio Alejandro; Lobos, Gustavo A.; García Gonzales, Rolando
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    Development and characterization of microsatellite markers in Gaultheria pumila Lf. (Ericaceae)
    (2018) Carrasco Gálvez, Basilio Alejandro; Garcia Gonzales, Rolando.; Pico Mendoza, José.; Quiroz, Karla.; Cáceres, Pablo.; Chong Perez, Borys.; Pino, Hugo.; Seiltgens, Marjorie.; Greck, Eglis.; Caligari, Peter D. S.
    Abstract Background Polymorphic microsatellite markers were developed for Gaultheria pumila (Ericaceae) to evaluate genetic diversity and population structure within its native range in Chile. This is a very important Ericaceae endemic to Chile with a large commercial potential. Its resistance to different abiotic conditions makes it a valuable target for genetic improvement. Results Ten polymorphic simple sequence repeat (SSR) loci were isolated from Gaultheria pumila using new-generation 454 FLX Titanium pyrosequencing technology. The mean number of alleles per locus ranged from 2 to 4. Observed and expected heterozygosity ranged from 0.00 to 1.0 and 0.00 to 0.64, respectively. Conclusions From 10 SSR markers developed for G. pumila, 9 markers are promising candidates for analyzing genetic variation within or between natural populations of G. pumila and other species from the same genus.
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    Efficient protocols for the extraction of microbial DNA from the rhizosphere of hydrophilic forests in Chile
    (PONTIFICIA UNIV CATOLICA CHILE, FAC AGRONOMIA INGENIERIA FORESTAL, 2012) Caceres, Pablo; Cordero, Cecilia; Gonzalez, Gloria; Quiroz, Karla; Bobadilla, Juan C.; Bravo, Carmen; Caligari, Peter D. S.; Carrasco, Basilio; Garcia Gonzales, Rolando
    P. Caceres, C. Cordero, G. Gonzalez, K. Quiroz, J.C. Bobadilla, C. Bravo, P.D.S. Caligari, B. Carrasco, and R. Garcia-Gonzales. 2012. Efficient protocols for the extraction of microbial DNA from the rhizosphere of hydrophilic forests in Chile. Cien. Inv. Agr. 38(3): 585-592. A lysis buffer-based protocol (Protocol BA), a modified lysis buffer-based protocol (Protocol BA Mod) and a commercial extraction kit (Protocol PS Kit) (Power Soil, Mo bio Laboratories, CA USA) were each evaluated for their ability to produce high-quality DNA with yields sufficient to allow its use in biodiversity studies. Similarly, the effect of liquid nitrogen on the process of cell disruption in all of the protocols that were studied. DNA yields ranged from 12.4 ng g(-1) of processed soil to 9620 ng g(-1) using the modified lysis buffer and commercial extraction kit, respectively. The quality of the DNA was determined by the ability of the DNA to produce efficient and reproducible polymerase chain reaction (PCR) products, using primers for universal 16S and 18S ribosomal RNA regions from bacteria and fungi, respectively. High-quality DNA was obtained to run PCRs in all protocols, but the efficiency of the method depended on the dilution of the DNA prior to performing the PCR. The three extraction methods generated PCR products with 90% efficiency. The DNA produced with the commercial kit was able to produce the highest PCR efficiency (95%) when the 10(-1) dilution was used. The method based on the use of lysis buffer produced the highest efficiency (90%) using a 10(-2) dilution. Meanwhile, the modified lysis buffer-based protocol generated the highest efficiency of PCR products using the 10(-3) dilution factor with 95% of efficiency. For the first time, reliable and efficient DNA isolation from the rhizosphere of hydrolic forest is documented, enabling a wide range of applications for this technique.
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    Genetic structure of highland papayas (Vasconcellea pubescens (Lenn, et C. Koch) Badillo) cultivated along a geographic gradient in Chile as revealed by Inter Simple Sequence Repeats (ISSR)
    (SPRINGER, 2009) Carrasco, Basilio; Avila, Patricio; Perez Diaz, Jorge; Munoz, Patricio; Garcia, Rolando; Lavandero, Blas; Zurita Silva, Andres; Retamales, Jorge B.; Caligari, Peter D. S.
    In Chile Vasconcellea pubescens is cropped to produce canned fruit, juice, jam and processed sweets. Additionally this species produces latex with a high level of papain, an important and valuable proteolytic enzyme with industrial applications. In this investigation seven ISSR primers were used to study the level and organization of genetic diversity in 333 samples of V. pubescens. Out of the 114 bands recorded, 63 proved to be polymorphic (P = 55.3%). At the species level, the genetic diversity was rather low (h = 0.01 +/- A 6,80188E-05, Shannon's Index I = 0.16 +/- A 0,000148). The major portion of the genetic diversity was found within groups (65%). The genetic differentiation between the different groups was significant, as the AMOVA analysis suggested (I broken vertical bar(pt) = 0.35). When analysing the Northern area alone, the differentiation increased to I broken vertical bar(pt) = 0.40. When only the Southern area was analysed, I broken vertical bar(pt) decreased to 0.18, indicating greater genetic similarity among the samples. The results generated from Structure and Bayesian Analysis of Population Structure distinguished 8 genetically different groups, five of them located in the north and three in the south. The results are discussed in the light of the growers' practices.
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    In vitro propagation of cedar (Cedrela odorata L.) from juvenile shoots
    (2011) García Gonzáles, Rolando; Delgado, Miladys; González, Yailín; González, Aníbal; Garriga, Miguel; Caligari, Peter D. S.; Carrasco Gálvez, Basilio Alejandro; Quiroz Bravo, Karla
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    Meristem culture and subsequent micropropagation of chilean strawberry (Fragaria chiloensis (L.) Duch.)
    (2017) Quiroz, Karla A.; Carrasco Gálvez, Basilio Alejandro; Berríos, Miguel.; Retamales, Jorge B.; Caligari, Peter D. S.; García-Gonzáles, Rolando.
    Abstract Background Vegetative propagation of Fragaria sp. is traditionally carried out using stolons. This system of propagation, in addition to being slow, can spread plant diseases, particularly serious being viral. In vitro culture of meristems and the establishment of micropropagation protocols are important tools for solving these problems. In recent years, considerable effort has been made to develop in vitro propagation of the commercial strawberry in order to produce virus-free plants of high quality. These previous results can serve as the basis for developing in vitro-based propagation technologies in the less studied species Fragaria chiloensis. Results In this context, we studied the cultivation of meristems and establishment of a micropropagation protocol for F. chiloensis. The addition of polyvinylpyrrolidone (PVP) improved the meristem regeneration efficiency of F. chiloensis accessions. Similarly, the use of 6-benzylaminopurine (BAP) in the culture media increased the average rate of multiplication to 3–6 shoots per plant. In addition, the use of 6-benzylaminopurine (BAP), had low levels (near zero) of explant losses due to oxidation. However, plant height as well as number of leaves and roots were higher in media without growth regulators, with average values of 0.5 cm, 9 leaves and 4 roots per plant. Conclusions For the first time in Chilean strawberry, meristem culture demonstrated to be an efficient tool for eliminating virus from infected plants, giving the possibility to produce disease free propagation material. Also, the addition of PVP into the basal MS medium improved the efficiency of plant recovery from isolated meristems. Farmers can now access to high quality plant material produced by biotech tools which will improve their technological practices.Abstract Background Vegetative propagation of Fragaria sp. is traditionally carried out using stolons. This system of propagation, in addition to being slow, can spread plant diseases, particularly serious being viral. In vitro culture of meristems and the establishment of micropropagation protocols are important tools for solving these problems. In recent years, considerable effort has been made to develop in vitro propagation of the commercial strawberry in order to produce virus-free plants of high quality. These previous results can serve as the basis for developing in vitro-based propagation technologies in the less studied species Fragaria chiloensis. Results In this context, we studied the cultivation of meristems and establishment of a micropropagation protocol for F. chiloensis. The addition of polyvinylpyrrolidone (PVP) improved the meristem regeneration efficiency of F. chiloensis accessions. Similarly, the use of 6-benzylaminopurine (BAP) in the culture media increased the average rate of multiplication to 3–6 shoots per plant. In addition, the use of 6-benzylaminopurine (BAP), had low levels (near zero) of explant losses due to oxidation. However, plant height as well as number of leaves and roots were higher in media without growth regulators, with average values of 0.5 cm, 9 leaves and 4 roots per plant. Conclusions For the first time in Chilean strawberry, meristem culture demonstrated to be an efficient tool for eliminating virus from infected plants, giving the possibility to produce disease free propagation material. Also, the addition of PVP into the basal MS medium improved the efficiency of plant recovery from isolated meristems. Farmers can now access to high quality plant material produced by biotech tools which will improve their technological practices.
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    Plant tissue culture : current status, opportunities and challenges.
    (2010) García González, Rolando; Quiroz Bravo, Karla; Carrasco Galvez, Basil Alexander; Caligari, Peter D. S.