Optimizing multi-environment testing in potato breeding: using heritability estimates to determine number of replications, sites, and years for field trials

Multi-environment trials (METs) of potato breeding clones and cultivars allow to precisely determine their performance across testing sites over years. However, these METs may be affected by the genotype × environment interaction (GEI) as noted in tuber yield. Furthermore, trials are replicated several times to optimize the predictive value of the data collected because knowledge on spatial and temporal variability of testing environments is often lacking. Hence, the objectives of this research were to use components of variance from METs to estimate broad sense heritability (H2) based on best linear unbiased predictors and use these estimates to determine the optimum number of sites, years, and replications for testing potato breeding clones along with cultivars. The data were taken from METs in southern and northern Sweden comprising up to 256 breeding clones and cultivars that underwent testing using a simple lattice design of 10-plant plots across three sites over 2 years. Percentage starch in the tuber flesh had the largest H2 in each testing environment (0.850–0.976) or across testing environments (0.905–0.921). Total tuber weight per plot also exhibited high H2 (0.720–0.919) in each testing environment or across them (0.726–0.852), despite a significant GEI. Reducing sugar content in the tuber flesh had the lowest, but still medium H2 (0.426–0.883 in each testing environment; 0.718–0.818 across testing environments). The H2 estimates were smaller when their variance components were disaggregated by year and site, instead of lumping them as environments. Simulating H2 with genetic, site, year, site × year, genetic × site, genetic × year, genetic × site × year, and residual variance components led to establish that two replicates at each of two sites in 2-year trials will suffice for testing tuber yield, starch and reducing sugars. This article provides a methodology to optimize the number of testing size and years for METs of potato breeding materials, as well as tabulated information for choosing the appropriate number of trials in same target population of environments

EFECTO DE LA LAMBDA-CIHALOTRINA EN EL DESPRENDIMIENTO DE LA OOTECA, EN LA VIABILIDAD Y MOTILIDAD ESPERMÁTICA DE BLATELLA GERMANICA (L.)(DICTYOPTERA: BLATELLIDAE)

Las cucarachas son una de las plagas domésticas más importantes a nivel mundial. El objetivo del presente estudio fue evaluar la exposición de la lambda-cihalotrina sobre el desprendimiento de la ooteca, y la viabilidad y motilidad espermática de Blatella germanica (Linnaeus). No se observó desprendimiento prematuro de la ooteca en las hembras, pero si una mayor mortalidad en machos (TL = 1h 6 min) que en hembras sin ootecas (TL = 1h 54 min). La lambda-cihalotrina 50 50 produjo efectos en la inhibición de la viabilidad (CE = 1130 mg·L-1) y la motilidad espermática 50 (CE = 660, 6 mg·L-1) de B. germanica

Partial least squares enhance multi-trait genomic prediction of potato cultivars in new environments

It is of paramount importance in plant breeding to have methods dealing with large numbers of predictor variables and few sample observations, as well as efficient methods for dealing with high correlation in predictors and measured traits. This paper explores in terms of prediction performance the partial least squares (PLS) method under single-trait (ST) and multi-trait (MT) prediction of potato traits. The first prediction was for tested lines in tested environments under a five-fold cross-validation (5FCV) strategy and the second prediction was for tested lines in untested environments (herein denoted as leave one environment out cross validation, LOEO). There was a good performance in terms of predictions (with accuracy mostly > 0.5 for Pearson’s correlation) the accuracy of 5FCV was better than LOEO. Hence, we have empirical evidence that the ST and MT PLS framework is a very valuable tool for prediction in the context of potato breeding data

Anales de la Facultad de Medicina 1995-2015: análisis y perspectivas en el rol de la difusión científica en nuestro país

First published in 1918, Anales de la Facultad de Medicina is the official journal of San Fernando Faculty of Medicine, Universidad Nacional Mayor de San Marcos. Following some years of absence, Anales was again published in 1995, under the direction of Dean José Piscoya Arbañil. Most of the Editorial Staff was later included in the new Editorial Committee in 2000 under the direction of José Pacheco Romero. Permanence, punctuality, visibility and impact distinguished the 15 years of administration of the journal despite editorial and financing limitations. Anales has received support from all the Faculty of Medicine Deans and the University Research Vice-Rector. It has obtained important indizations, and has digitized all journal articles and their respective doi since 1918, allowing more visits, article discharges and citations.La Revista Anales de la Facultad de Medicina, órgano oficial de la Facultad de Medicina San Fernando de la Universidad Nacional Mayor de San Marcos fue publicada por primera vez en 1918. El año 1995 reapareció después de algunos años de ausencia, bajo la dirección del entonces Decano de la Facultad de Medicina Dr. José Piscoya Arbañil. La mayor parte del Comité Editorial de entonces conformó el Comité Editorial que, desde el año 2000, bajo la conducción del Dr. José Pacheco Romero, ha continuado publicando la Revista con permanencia, puntualidad, visibilidad e impacto, cumpliendo el presente año 2015 quince años de gestión. A pesar de las limitaciones de recursos editoriales y financiamiento, la Revista recibió el apoyo de los diferentes Decanos y del Vicerrectorado de Investigación, habiendo sido incorporada en importantes indizadoras, así como ha digitalizado todos los artículos de Anales desde 1918 que aparecen de manera virtual en internet, con sus respectivos doi, lo que brinda más visitas, descargas y citaciones

Efecto de la lambda-cihalotrina en el desprendimiento de la ooteca, en la viabilidad y motilidad espermática de blatella germanica (l.)(dictyoptera: blatellidae)

Cockroaches are one of the most important worldwide household pests. The objective of the current research was to assess exposure of lambda-cyhalothrin on release of ootheca, and sperm viability and motility of Blatella germanica (Linnaeus). No premature release of female oothecas were evident, but mortality in males (LT = 1h 6 min) was higher than in females (LT = 1h 54 50 50 min). Lambda-cyhalothrin produced effects on inhibition of sperm viability (EC = 1130 mg·L-1) 50 and sperm motility (EC = 660, 6 mg·L-1) of B. germanica.Las cucarachas son una de las plagas domésticas más importantes a nivel mundial. El objetivo del presente estudio fue evaluar la exposición de la lambda-cihalotrina sobre el desprendimiento de la ooteca, y la viabilidad y motilidad espermática de Blatella germanica (Linnaeus). No se observó desprendimiento prematuro de la ooteca en las hembras, pero si una mayor mortalidad en machos (TL = 1h 6 min) que en hembras sin ootecas (TL = 1h 54 min). La lambda-cihalotrina 50 50 produjo efectos en la inhibición de la viabilidad (CE = 1130 mg·L-1) y la motilidad espermática 50 (CE = 660, 6 mg·L-1) de B. germanica

Partial least squares enhance multi-trait genomic prediction of potato cultivars in new environments

Abstract It is of paramount importance in plant breeding to have methods dealing with large numbers of predictor variables and few sample observations, as well as efficient methods for dealing with high correlation in predictors and measured traits. This paper explores in terms of prediction performance the partial least squares (PLS) method under single-trait (ST) and multi-trait (MT) prediction of potato traits. The first prediction was for tested lines in tested environments under a five-fold cross-validation (5FCV) strategy and the second prediction was for tested lines in untested environments (herein denoted as leave one environment out cross validation, LOEO). There was a good performance in terms of predictions (with accuracy mostly > 0.5 for Pearson’s correlation) the accuracy of 5FCV was better than LOEO. Hence, we have empirical evidence that the ST and MT PLS framework is a very valuable tool for prediction in the context of potato breeding data

Anales de la Facultad de Medicina 1995-2015: análisis y perspectivas en el rol de la difusión científica en nuestro país

First published in 1918, Anales de la Facultad de Medicina is the official journal of San Fernando Faculty of Medicine, Universidad Nacional Mayor de San Marcos. Following some years of absence, Anales was again published in 1995, under the direction of Dean José Piscoya Arbañil. Most of the Editorial Staff was later included in the new Editorial Committee in 2000 under the direction of José Pacheco Romero. Permanence, punctuality, visibility and impact distinguished the 15 years of administration of the journal despite editorial and financing limitations. Anales has received support from all the Faculty of Medicine Deans and the University Research Vice-Rector. It has obtained important indizations, and has digitized all journal articles and their respective doi since 1918, allowing more visits, article discharges and citations.La Revista Anales de la Facultad de Medicina, órgano oficial de la Facultad de Medicina San Fernando de la Universidad Nacional Mayor de San Marcos fue publicada por primera vez en 1918. El año 1995 reapareció después de algunos años de ausencia, bajo la dirección del entonces Decano de la Facultad de Medicina Dr. José Piscoya Arbañil. La mayor parte del Comité Editorial de entonces conformó el Comité Editorial que, desde el año 2000, bajo la conducción del Dr. José Pacheco Romero, ha continuado publicando la Revista con permanencia, puntualidad, visibilidad e impacto, cumpliendo el presente año 2015 quince años de gestión. A pesar de las limitaciones de recursos editoriales y financiamiento, la Revista recibió el apoyo de los diferentes Decanos y del Vicerrectorado de Investigación, habiendo sido incorporada en importantes indizadoras, así como ha digitalizado todos los artículos de Anales desde 1918 que aparecen de manera virtual en internet, con sus respectivos doi, lo que brinda más visitas, descargas y citaciones