MULTIVARIATE ANALYSES OF POTATO HYBRIDS. I. DISCRIMINATION BETWEEN TETRAPLOID-DIPLOID HYBRID FAMILIES AND THEIR RELATIONSHIP TO CULTIVARS

1980 ◽  
Vol 22 (2) ◽  
pp. 227-235 ◽  
Author(s):  
G. C. C. Tai ◽  
H. De Jong
Keyword(s):  
Potato Breeding ◽  
Multivariate Analyses ◽  
Field Trials ◽  
Canonical Analysis ◽  
Diploid Hybrid ◽  
Horticultural Traits ◽  
Mean Vectors ◽  
Group Tuberosum ◽  
Substantial Distance

Clones of ten 4x-2x hybrid families were obtained by crossing five Group Tuberosum parents with each of two (Group Phureja × haploid Group Tuberosum) parents. The performances of horticultural traits of the 4x-2x progenies were distinctly different from those of the 4x parents and cultivars. Multivariate analyses of eight traits were performed on data of each of the three field trials in 1976, 1977 and 1978 and on the means of clones over the three years. Multivariate analyses of variance indicated significant differences between mean vectors of the 4x-2x families. Canonical analysis based on means of clones revealed clearly the effects of 4x and 2x parents on the distributions of the 4x-2x families. However, analysis of canonical distances between the hybrid families also suggested the possible existence of interactions of 4x and 2x parents. Substantial distance was observed between the 4x-2x families and the 4x parents and cultivars. The results lead to a discussion on future strategies of using the 4x-2x hybrids in potato breeding.

scholarly journals A nonS-locus F-box gene breaks self-incompatibility in diploid potatoes

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ling Ma ◽  
Chunzhi Zhang ◽  
Bo Zhang ◽  
Fei Tang ◽  
Futing Li ◽  
...  
Keyword(s):  
Potato Breeding ◽  
Inbred Lines ◽  
Hybrid Breeding ◽  
Self Incompatibility ◽  
Diploid Hybrid ◽  
Food Crop ◽  
Global Food Security ◽  
The Third ◽  
Self Compatibility ◽  
Global Food

AbstractPotato is the third most important staple food crop. To address challenges associated with global food security, a hybrid potato breeding system, aimed at converting potato from a tuber-propagated tetraploid crop into a seed-propagated diploid crop through crossing inbred lines, is under development. However, given that most diploid potatoes are self-incompatible, this represents a major obstacle which needs to be addressed in order to develop inbred lines. Here, we report on a self-compatible diploid potato, RH89-039-16 (RH), which can efficiently induce a mating transition from self-incompatibility to self-compatibility, when crossed to self-incompatible lines. We identify the S-locusinhibitor (Sli) gene in RH, capable of interacting with multiple allelic variants of the pistil-specific S-ribonucleases (S-RNases). Further, Sli gene functions like a general S-RNase inhibitor, to impart SC to RH and other self-incompatible potatoes. Discovery of Sli now offers a path forward for the diploid hybrid breeding program.

scholarly journals Field Evaluation of CRISPR-Driven Jointless Pedicel Fresh-Market Tomatoes

Agronomy ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1957
Author(s):  
Tong Geon Lee ◽  
Samuel F. Hutton
Keyword(s):  
Large Scale ◽  
Fruit Size ◽  
Field Evaluation ◽  
Field Trials ◽  
Growth Conditions ◽  
Isogenic Line ◽  
Fresh Market ◽  
New Variety ◽  
Horticultural Traits ◽  
Tomato Field

Clustered regularly interspaced short palindromic repeats (CRISPR)-driven traits are commonly introduced into tomato (Solanum lycopersicum) in less than a year. Although CRISPR technology is highly suitable for rapid incorporation of new traits into plants with superior breeding backgrounds, the usefulness of these traits must be demonstrated prior to large-scale distribution of any new variety possessing them. The jointless pedicel trait is crucial for stem-free harvest of tomato fruits and is therefore an essential requirement for developing low-labor tomato varieties. We aimed to evaluate the effect of CRISPR-driven jointless pedicel trait on the yield and horticultural traits of fresh-market tomatoes. We conducted field trials during three consecutive seasons using three related genotypes of two elite fresh-market tomatoes, namely a jointed pedicel tomato, a CRISPR-driven jointless pedicel mutant of the jointed pedicel tomato, and a conventionally-bred jointless pedicel near isogenic line (NIL) to the jointed pedicel tomato. Field evaluations confirmed that the total and medium-, large-, or extra-large-size fruit yields of the CRISPR-driven mutants were not statistically different for those corresponding to their backgrounds and that the fruit yield stratified by fruit size might be varied under different growth conditions. We did not observe any negative correlation between the genotype and the fruit/abscission joint detachment force for any of the genotypes under study.

Geographic Patterns of Genetic Variation in Eucalyptus globulus ssp. globulus and a Revised Racial Classification

1999 ◽  
Vol 47 (2) ◽  
pp. 237 ◽  
Author(s):  
G. W. Dutkowski ◽  
B. M. Potts
Keyword(s):  
Genetic Variation ◽  
Eucalyptus Globulus ◽  
Multivariate Analyses ◽  
Basic Density ◽  
Field Trials ◽  
Racial Classification ◽  
Regional Patterns ◽  
Growth And Survival ◽  
Geographic Patterns ◽  
Quantitative Genetic

The geographic patterns of genetic variation in a wide variety of quantitative traits were studied in Eucalyptus globulus ssp. globulus and its intergrades, leading to a revised racial classification. The analysis was based on 35 traits assessed in five field trials in northern Tasmania from approximately 500 open-pollinated families, encompassing 49 collection localities in native stands. There were significant differences between the collection localities for most traits. While growth and survival traits exhibited weak spatial structuring, there were clear regional patterns in bark thickness, wood basic density, flowering precocity and some aspects of juvenile leaf morphology. There were a number of significant correlations between trait locality means, but few simple correlations between the regional patterns observed and climate. Multivariate analyses indicated that the localities could be effectively amalgamated into larger, geographically concordant races. A hierarchy of five major groupings of 13 races and 20 subraces is proposed to account for most of the quantitative genetic variation while allowing for outliers and intermediate populations. Some areas of the distribution may need further sampling to more accurately elucidate their racial affinities, especially those with traits of high economic importance.

scholarly journals Identification of the High Frequency of Triploid Potato Resulting from Tetraploid × Diploid Crosses

HortScience ◽  
2019 ◽  
Vol 54 (7) ◽  
pp. 1159-1163
Author(s):  
Ryan C. Graebner ◽  
Hsuan Chen ◽  
Ryan N. Contreras ◽  
Kathleen G. Haynes ◽  
Vidyasagar Sathuvalli
Keyword(s):  
High Frequency ◽  
Potato Breeding ◽  
Unreduced Gametes ◽  
Hybrid Population ◽  
Development Programs ◽  
Diploid Hybrid ◽  
Diploid Parent ◽  
Genomic Studies ◽  
Triploid Block ◽  
Triploid Clones

Conventional wisdom regarding potato breeding indicates that a strong triploid block prevents the development of viable triploid seeds from crosses between tetraploid and diploid clones. However, in a recent set of crosses between elite tetraploid potatoes and an improved diploid hybrid population derived from group Stenotomum and group Phureja, 61.5% of the resulting clones were found to be triploid. If clones derived from one diploid parent suspected of producing a high frequency of unreduced gametes were excluded, then the frequency of triploid clones increased to 74.4%. Tubers of these triploids are generally intermediates of the two parental groups. Our findings indicate the possibility of using triploid potatoes in potato variety development programs and in genetic and genomic studies.

scholarly journals Little heterosis found in Diploid Hybrid Potato

2021 ◽  
Author(s):  
James Randall Adams ◽  
Chaozhi Zheng ◽  
Michiel E. de Vries ◽  
Fred A. van Eeuwijk
Keyword(s):  
Complex Traits ◽  
Potato Breeding ◽  
Diallel Analysis ◽  
Hybrid Breeding ◽  
Target Market ◽  
Hybrid Vigour ◽  
Diploid Hybrid ◽  
Genetic Components ◽  
Deleterious Alleles ◽  
Highly Correlated

Hybrid potato breeding has become a novel alternative to conventional potato breeding allowing breeders to overcome intractable barriers (e.g. tetrasomic inheritance, masked deleterious alleles, obligate clonal propagation) with the benefit of seed-based propagule, flexible population design, and the potential of hybrid vigour. Until now, however, no formal inquiry has adequately examined the relevant genetic components for complex traits in hybrid potato populations. In this present study, we use a two-step modelling approach to estimate the relevant variance components to assess the magnitude of the general and specific combining abilities (GCA and SCA, respectively) in diploid hybrid potato (DHP). SCA effects were identified for all yield components studied here warranting evidence of non-additive genetic effects in hybrid potato yield. However, the estimated GCA effects were on average two times larger than their respective SCA quantile across all yield phenotypes. Tuber number GCAs and SCAs were found to be highly correlated with total yield's genetic components. Tuber volume appearing under-selected in this population. The prominence of additive effects found for all traits presents evidence that breeders can perform hybrid potato evaluation using the mid-parent value alone. Heterotic vigour stands be useful in bolstering simpler traits but this will be very dependent on the target market of a population. This study represents the first diallel analysis of its kind in diploid potato using material derived from a commercial hybrid breeding programme.

scholarly journals Optimal Plot Dimensions for Performance Testing of Hybrid Potato in the Field

2021 ◽  
Author(s):  
Julia E. Stockem ◽  
George Korontzis ◽  
Stefan E. Wilson ◽  
Michiel E. de Vries ◽  
Fred A. van Eeuwijk ◽  
...  
Keyword(s):  
Potato Breeding ◽  
Tuber Yield ◽  
Performance Testing ◽  
Field Trials ◽  
Genetic Differences ◽  
Field Variation ◽  
Tuber Shape ◽  
Plot Size ◽  
Trial Field ◽  
New Varieties

Abstract Field trials to evaluate the performance of new varieties are an essential component of potato breeding. Besides the genetic differences, environmental factors can lead to variation in a trial. In variety trials, the observed differences amongst varieties should reflect genetic differences, without a large impact of the random or systematic variation in the field. One way to reduce within-field variation is to adjust the plot size and its shape in a trial. Two years of field trials in which individual plants in 90-plant plots of both diploid hybrid and tetraploid varieties were measured provided data to derive relationships between LSD% and plot size and shape. We provide a method to estimate the equations to calculate the expected variation when using different plot dimensions in a relatively homogeneous trial field for tuber yield, tuber volume, tuber count, tuber shape and the standard deviations of tuber volume and shape. Compared with the yield traits, the variation for tuber shape was relatively small. The effect of plot shape was minor. With these equations, breeders can determine what plot dimensions are needed to reach the desired precision for each trait.

Associations Between Informal Caregivers’ Burden and Educational Level

GeroPsych ◽  
2019 ◽  
Vol 32 (1) ◽  
pp. 19-29 ◽  
Author(s):  
Monika Oedekoven ◽  
Katja Amin-Kotb ◽  
Paul Gellert ◽  
Klaus Balke ◽  
Adelheid Kuhlmey ◽  
...  
Keyword(s):  
Support Services ◽  
Educational Level ◽  
Autonomy Support ◽  
Population Survey ◽  
Multivariate Analyses ◽  
Informal Caregivers ◽  
Loss Of Self ◽  
Perceived Burden ◽  
Result Show ◽  
Care Situation

Abstract. We investigated the association between the education of informal caregivers’ (IC) and their physical and mental burden. We hypothesized that better-educated IC would have more resources available to manage the care situation and as a result show lower perceived burden. We conducted a population survey of 6,087 German residents aged 18+ years, 966 of whom reported to be IC. Results show that IC felt more often mentally than physically burdened. In the multivariate analyses, higher-educated IC did not have lower odds of feeling physically burdened than lower-educated IC, though they did have increased odds of feeling mentally burdened. The higher perceived mental burden of higher-educated IC may be related to fear of loss of self-fulfilment and autonomy. Support services should consider the mental burden of higher-educated IC and tailor their interventions accordingly.

Subtypes of Attention Deficit Hyperactivity Disorder: Evidence From DSM-IV Field Trials

1995 ◽  
Author(s):  
B. B. Lahey ◽  
B. Applegate ◽  
K. McBurnett ◽  
J. Biederman ◽  
L. Greenhill ◽  
...  
Keyword(s):  
Attention Deficit Hyperactivity Disorder ◽  
Attention Deficit ◽  
Field Trials ◽  
Hyperactivity Disorder ◽  
Dsm Iv

Designing and Implementing Randomized Field Trials of Interventions in Schools

2007 ◽  
Author(s):  
George Bohrnstedt ◽  
Jeanne Poduska ◽  
Mike Garet ◽  
Sheppard Kellam ◽  
David Myers
Keyword(s):  
Field Trials ◽  
Randomized Field Trials
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