scholarly journals Path analysis under multiple-trait BLUP: application in the study of interrelationships among traits related to cotton fiber length

2021 ◽  
Vol 53 (1) ◽  
pp. 1-10
Author(s):  
Rodrigo Alves ◽  
João Rocha ◽  
Larissa Teodoro ◽  
Luiz Carvalho ◽  
Francisco Farias ◽  
...  
Keyword(s):  
Path Analysis ◽  
Fiber Length ◽  
Mixed Model ◽  
Fiber Quality ◽  
Genetic Correlations ◽  
Residual Effects ◽  
Phenotypic Variance ◽  
Multiple Trait ◽  
Effect Relationship ◽  
Cause And Effect

Multi-trait best linear unbiased prediction (BLUP) is, generally, the most appropriate method to genetic evaluation because it considers the genetic and residual correlations among traits and conduct to higher selection accuracy. Thus, the present study aimed to identify traits correlated to the fiber length via path analysis under multi-trait BLUP for the cotton breeding. To this end, thirty-six elite lines were evaluated in three environments and phenotyped for many traits related to fiber quality and agronomic traits. Variance components were estimated via residual maximum likelihood (REML). The genetic correlation coefficients among traits were obtained through mixed model output, and to graphically express these results a correlation network was built. Subsequently, we performed path analysis considering fiber length as a principal dependent variable. Genetic parameters obtained by multi-trait BLUP model indicate that the phenotypic variance for most traits is mostly composed of residual effects, which reinforces the need for using more accurate statistical methods such as multi-trait BLUP. The results found for genetic correlations and path analysis under multi-trait BLUP reveal the difficulty of selection based on important fiber quality traits, especially fiber length, since most traits show very low cause-and-effect relationship, and other important traits present undesirable cause-and-effect relationship. Highlights Multiple-trait BLUP is the most appropriate method to predict genetic values. This is the first study in cotton to perform path analysis under multiple-trait BLUP. The findings of this study indicate that there is no genotype presenting all desirable traits.

scholarly journals Path analysis of yield components in tropical pumpkin

1969 ◽  
Vol 90 (3-4) ◽  
pp. 183-191
Author(s):  
Miguel Espitia-Camacho ◽  
Franco A. Vallejo-Cabrera ◽  
Diosdado Baena-Garcia ◽  
Linda Wessel-Beaver
Keyword(s):  
Path Analysis ◽  
Indirect Effects ◽  
Block Design ◽  
Genetic Correlations ◽  
Fruit Weight ◽  
Residual Effects ◽  
Path Coefficient ◽  
Direct Effects ◽  
Randomized Complete Block Design ◽  
Effect On Yield

Path coefficient analysis was carried out in tropical pumpkin (Cucurbita moschata Duchesne) for yield per plant as a function of number of fruit per plant and weight per fruit, using phenotypic and genetic correlations from two diallels: one using five varieties (variety diallel) and a second using five S1 lines derived from the varieties (line diallel). A randomized complete block design with five replications was used to evaluate 15 genotypes from each diallel, not including reciprocals. Direct effects were 300 to 500% greater than indirect effects in the line diallel. In contrast, direct effects were only 17 to 68% greater than indirect effects in the variety diallel. Effects (direct and indirect) were greater (17 to 500%) when genetic correlations rather than phenotype correlations (42 to 440%) were used in the path analysis. Fruit weight showed a greater effect on yield than did number of fruit, with values between 3.2 to 4.9 times the residual effects. Fruit weight and number of fruit can be used as selection criteria to increase yield in tropical pumpkin.  

scholarly journals Mixed model analysis of a selection experiment for food intake in mice

1991 ◽  
Vol 57 (1) ◽  
pp. 71-81 ◽  
Author(s):  
K. Meyer ◽  
W. G. Hill
Keyword(s):  
Body Weight ◽  
Food Intake ◽  
Mixed Model ◽  
Selection Criterion ◽  
Residual Effects ◽  
Phenotypic Correlation ◽  
Selection Line ◽  
Phenotypic Variance ◽  
Mixed Model Analysis ◽  
Intraclass Correlations

SummaryData from 23 generations of mice selected for increased and reduced appetite were analysed by Restricted Maximum Likelihood fitting an animal model with litters as additional random effects. Traits considered were food intake between 4 and 6 weeks of age adjusted for 4-week body weight (AFI), the selection criterion, and body weight at 6 weeks (6WW). Selection was carried out within families. A high and a low selection line and a control were maintained in each of three replicates. Analyses were performed for each replicate separately taking subsets of the data spanning different numbers of generations. Overall estimates of heritabilities were 0·15 for AFI, which agreed well with realized heritability estimates, and 0·42 for 6WW. The litter variance, expressed as a proportion of the phenotypic variance, was 0·21 for both traits, yielding intraclass correlations of full-sibs of 0·29 and 0·42, respectively. Similar results were obtained for variances of each trait using univariate and multivariate analyses. From the latter, estimates of correlations between the two traits were 0·46 for additive genetic, −0·19 for litter and 0·31 for residual effects, resulting in a phenotypic correlation of 0·23. Analyses of data from generations 2–7, 8–13 and 14–23 separately showed a marked decrease in genetic variance and heritability in later generations for both traits. Heritabilities of AFI, for instance were 0·24, 0·10 and 0·07, respectively. These changes could not be attributed to the effects of inbreeding or of selection in an infinitesimal model and suggested that some change in variance due to change in gene frequency had occurred during the course of the experiment.

Estimation of genetic parameters for litter size in sheep: a comparison of a repeatability and a multivariate model

1998 ◽  
Vol 66 (3) ◽  
pp. 685-688 ◽  
Author(s):  
M. J. de Vries ◽  
E. H. van der Waaij ◽  
J. A. M. van Arendonk
Keyword(s):  
Animal Model ◽  
Genetic Correlation ◽  
Litter Size ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Multivariate Model ◽  
Phenotypic Variance ◽  
Multiple Trait ◽  
Environmental Correlations ◽  
Estimation Of Genetic Parameters

AbstractGenetic parameters were estimated for litter size in two prolific sheep breeds, i.e. the Zwartbles and the synthetic breed Swifter. Genetic parameters and breeding values for litter size in different parities were estimated using both a repeatability and a multivariate animal model. The estimated heritability from the repeatability model was 0·10 for the Zwartbles and 0·12 for the Swifter. For the multivariate model, heritability of litter size in first, second and third parity was 0·05, 0·07 and 0·10 for the Zwartbles and 0·09, 0·12 and 0·09 for the Swifter. Genetic correlation for litter size in Swifter was 0·81 between parity 1 and 2 and 0·99 between parity 2 and 3. For the Zwartbles genetic correlations were all very close to unity. Environmental correlations between litter size in subsequent parities were not constant over parities. Phenotypic variance in litter size in both breeds was 0·309 in first parity and was almost 50% higher in later parities. Based on the results it is recommended to apply a multiple trait model.

scholarly journals Childhood asthma and vitamin D deficiency in Turkey: is there cause and effect relationship between them?

2013 ◽  
Vol 39 (1) ◽  
Author(s):  
Metin Uysalol ◽  
Levent Cem Mutlu ◽  
Gamze Varol Saracoglu ◽  
Erkut Karasu ◽  
Savas Guzel ◽  
...  
Keyword(s):  
Vitamin D ◽  
Vitamin D Deficiency ◽  
Childhood Asthma ◽  
Effect Relationship ◽  
Cause And Effect

scholarly journals Diabetes and sleep: A complex cause-and-effect relationship

2011 ◽  
Vol 91 (2) ◽  
pp. 129-137 ◽  
Author(s):  
Mark T.U. Barone ◽  
Luiz Menna-Barreto
Keyword(s):  
Effect Relationship ◽  
Cause And Effect

Isoniazid as a Cause of Optic Neuritis and Atrophy

PEDIATRICS ◽  
1957 ◽  
Vol 20 (5) ◽  
pp. 865-865
Keyword(s):  
Optic Neuritis ◽  
Gradual Improvement ◽  
Effect Relationship ◽  
Cause And Effect ◽  
Neurotoxic Effects ◽  
Eye Lesions

Two patients are reported in whom there was an association between the occurrence of optic neuritis with atrophy and the administration of isoniazid for the treatment of tuberculosis. Although a cause and effect relationship was not established, discontinuation of isoniazid therapy in one patient was followed by gradual improvement of the eye lesions. The authors assume that the optic lesions were neurotoxic effects of isoniazid and recommend that pyridoxine be given daily for prophylaxis.

The incorporation of fertility indices in genetic improvement programmes

2001 ◽  
Vol 26 (1) ◽  
pp. 237-249 ◽  
Author(s):  
J.E. Pryce ◽  
R.F. Veerkamp
Keyword(s):  
Genetic Variance ◽  
Selection Index ◽  
Genetic Correlations ◽  
Live Weight ◽  
Parameter Estimates ◽  
Phenotypic Variance ◽  
Production Traits ◽  
Genetic Progress ◽  
Detection Rates ◽  
Days Open

AbstractIn recent years there has been considerable genetic progress in milk production. Yet, increases in yield have been accompanied by an apparent lengthening of calving intervals, days open, days to first heat and a decline in conception rates, which appears to be both at the genetic and phenotypic level. Fertility has a high relative economic value compared to production traits such as protein, making it attractive to include in a breeding programme. To do this there needs to be genetic variance in fertility. Measures of fertility calculated from service dates have a small genetic compared to phenotypic variance, hence heritability estimates are small, typically less than 5%, although coefficients of genetic variance are comparable to those of production traits. Heritabilities of commencement of luteal activity determined using progesterone profiles are generally higher, and have been reported as being from 0.16 to 0.28, which could be because of a more precise quantification of genetic variance, as management influences such as delaying insemination and heat detection rates are excluded. However, it might not be the use of progesterone profiles alone, as days to first heat observed by farm staff has a heritability of 0.15. The most efficient way to breed for improved fertility is to construct a selection index using the genetic and phenotypic parameter estimates of all traits of interest in addition to their respective economic values. Index traits for fertility could include measures such as calving interval, days open, days to first service, or days to first heat but there may also be alternative measures. Examples include traits related to energy balance, such as live weight and condition score (change), both of which have higher heritabilities than fertility measures and have genetic correlations of sufficient magnitude to make genetic progress by using them feasible. To redress the balance between fertility and production, some countries already publish genetic evaluations of fertility including: Denmark, Finland, France, Germany, Israel, The Netherlands, Norway and Sweden.

Transplanting improves the allometry and fiber quality of Bt cotton in cotton–wheat cropping system

2019 ◽  
Vol 56 (1) ◽  
pp. 26-36
Author(s):  
Muhammad Asghar Shah ◽  
Mubshar Hussain ◽  
Muhammad Shahzad ◽  
Khawar Jabran ◽  
Sami Ul-Allah ◽  
...  
Keyword(s):  
Fiber Length ◽  
Fiber Strength ◽  
Management Practice ◽  
Cropping Systems ◽  
Fiber Quality ◽  
Cropping System ◽  
Bt Cotton ◽  
Area Index ◽  
Fiber Fineness

AbstractIn cotton–wheat cropping system of Pakistan, wheat (Triticum aestivum L.) is harvested in late April; however, the optimum sowing time of Bt cotton is mid-March. This indicates a time difference of 4–6 weeks between the harvest of wheat and cotton sowing. It is hypothesized that this overlapping period may be managed by transplanting cotton seedlings (30–45 days old) in late April, after the harvest of wheat due to better performance of already established seedlings. To this end, this study was conducted to evaluate the allometric traits and fiber quality of transplanted Bt cotton after harvesting wheat in the cotton–wheat cropping system. The Bt cotton–wheat cropping systems were flat sown wheat (FSW)–conventionally tilled cotton, FSW–zero tilled cotton, ridge sown wheat–ridge transplanted cotton using 30- and 45-days-old seedlings, and bed sown wheat (BSW)–bed transplanted cotton (BTC) also using 30- and 45-days-old seedlings. The study was conducted at Vehari and Multan in Punjab, Pakistan. Bt cotton in BSW–BTC with 45-days-old seedlings showed better performance for allometric (leaf area index; (LAI), net assimilation rate; (NAR), and crop growth rate; (CGR)), seed cotton yield, and fiber traits (fiber uniformity, fiber length, fiber strength, and fiber fineness) in comparison to other treatments. Most of the fiber quality traits were positively correlated with allometric traits and biological yield (dry matter yield at maturity) at both locations, except correlations of CGR and LAI with fiber fineness and fiber length and NAR with fiber length. As plant growth and fiber quality of transplanted cotton was significantly higher than conventionally grown cotton, our data indicate transplanting is an interesting management practice for improving productivity in wheat–cotton cropping systems.

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