Growth regulators and darkness increase efficiency on in vitro culture of immature embryos from peppers

[EN] Common pepper (Capsicum annuum L.) is one of the most important vegetables in the world, and extensive breeding efforts are being made to develop new improved strains of this species. In this regard, in vitro culture of immature embryos may help breeders accelerate breeding cycles and overcome interspecific barriers, among other applications. In this study, we have optimized a protocol for in vitro culture of immature embryos of C. annuum. Levels of indole-3-acetic acid (IAA) and zeatin have been tested to improve the efficiency (germination rates) of this technique in C. annuum embryos at the four main immature stages (i.e. globular, heart, torpedo, and early cotyledonary) from four varietal types of this species (California Wonder, Piquillo, Guindilla, and Bola). The effect of 5-day initial incubation in the dark was also tested on the most efficient hormone formulation. On average, relatively low levels of both IAA and zeatin (0.01 mg L-1 each) (M-1) provided the highest germination rates, particularly in the advanced stages (torpedo and cotyledonary). To a lesser extent, the lack of these growth regulators (M-0) or high IAA (0.2 mg L-1)/low zeatin (0.01 mg L-1) (M-2) combination also had a positive response. On the contrary, high zeatin levels (0.2 mg L-1) produced very low germination rates or callus development (efficiency 0-7 %). Different responses were also found between genotypes. Thus, considering the best media (M-0, M-1, M-2), Bola embryos had the highest rates. M-1 plus 5-days of initial dark incubation (M-1-D) improved the efficiency rates at all embryo stages, particularly in the earliest (globular) embryos which increased from 3 % to > 20 %.Juan P. Manzur thanks Polytechnic University of Valencia for a research grant (2011-S2-4264, research staff training program, FPI). This work has been co-financed by INIA projects RTA2010-00038-C03-03 and RF2010-00025-00-00, and FEDER fundings. The authors thank NEIKER and the Regulatory Boards of D.O.P. Pimenton de Murcia and D.O.P. Pimiento del Piquillo de Lodosa for providing us with seeds of Guindilla de Ibarra, Bola and Piquillo.Manzur Poblete, JPA.; Calvache Asensio, MDLN.; Rodríguez Burruezo, A. (2014). Growth regulators and darkness increase efficiency on in vitro culture of immature embryos from peppers. Scientia Agricola. 71(6):488-493. https://doi.org/10.1590/0103-9016-2013-0230S48849371

In vitro propagation of purple pitahaya (Hylocereus costaricensis [F.A.C. Weber] Britton & Rose) cv. Cebra

Limitations to large-scale propagation of purple pitahaya (Hylocereus costaricensis [F.A.C. Weber] Britton & Rose), a potential source of betalains for the food industry, can be overcome through utilization of in vitro culture technologies. In this work, successful in vitro propagation from areoles of adult purple pitahaya plants is reported. Factors affecting culture initiation, bud sprouting and growth, shoot multiplication, rooting, and acclimatization were studied. Best results for culture initiation were obtained from the central region of new joints by disinfection of large (5–7 cm in length) explants that were subsequently divided. Explants were sequentially treated with Extran® alkaline detergent for 10 min, followed by immersion in 70 % (v/v) ethanol for 15–30 s, a mixture of the fungicide Benomyl and the bactericide Agrymicin (2 g l−1 each) for 30 min, and disinfection in sodium hypochlorite (1.0 % w/v) for 15 min. Culture of sectioned individual areoles, without removing thorns, on Murashige and Skoog medium supplemented with 15 or 30 μM N 6-benzylaminopurine (BAP) for 3 mo with monthly subcultures, followed by transfer to the same medium with reduced BAP (0–2 μM), induced bud sprouting in over 80 % of explants, adequate growth of the shoots, with production of lateral shoots, and spontaneous rooting within 160 d. These plants were successfully acclimatized in vermiculite and peat moss (1:1), or perlite and peat moss (2:1) in the greenhouse, with over 90 % survival rate. One hundred percent of the in vitro-derived plants were successfully transferred to the field. Furthermore, these plants showed higher survival rates, larger height and increase in stem diameter than equivalent plants from the same genotype, derived from stem segments (the common clonal propagation system utilized for this species) that were simultaneously planted.Universidad de Costa Rica/[734-A5-029]/UCR/Costa RicaUCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Agroalimentarias::Centro para Investigaciones en Granos y Semillas (CIGRAS

ENIGMA--evidence-based network for the interpretation of germline mutant alleles:an international initiative to evaluate risk and clinical significance associated with sequence variation in BRCA1 and BRCA2 genes

As genetic testing for predisposition to human diseases has become an increasingly common practice in medicine, the need for clear interpretation of the test results is apparent. However, for many disease genes, including the breast cancer susceptibility genes BRCA1 and BRCA2, a significant fraction of tests results in the detection of a genetic variant for which disease association is not known. The finding of an “unclassified” variant (UV)/variant of uncertain significance (VUS) complicates genetic test reporting and counseling. As these variants are individually rare, a large collaboration of researchers and clinicians will facilitate studies to assess their association with cancer predisposition. It was with this in mind that the ENIGMA consortium (www.enigmaconsortium.org) was initiated in 2009. The membership is both international and interdisciplinary, and currently includes more than 100 research scientists and clinicians from 19 countries. Within ENIGMA, there are presently six working groups focused on the following topics: analysis, clinical, database, functional, tumor histopathology, and mRNA splicing. ENIGMA provides a mechanism to pool resources, exchange methods and data, and coordinately develop and apply algorithms for classification of variants in BRCA1 and BRCA2. It is envisaged that the research and clinical application of models developed by ENIGMA will be relevant to the interpretation of sequence variants in other disease genes