scholarly journals Screening of Popcorn Genotypes for Drought Tolerance Using Canonical Correlations

Agronomy ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1519
Author(s):  
Samuel Henrique Kamphorst ◽  
Gabriel Moreno Bernardo Gonçalves ◽  
Antônio Teixeira do Amaral Júnior ◽  
Valter Jário de Lima ◽  
Jhean Torres Leite ◽  
...  
Keyword(s):  
Root Traits ◽  
Grain Filling ◽  
Inbred Lines ◽  
Agricultural Activities ◽  
Canonical Correlations ◽  
Water Condition ◽  
Crown Root ◽  
Selection For ◽  
Leaf Greenness ◽  
Condition Interaction

Getting around the damage caused by drought is a worldwide challenge, particularly in Brazil, given that economy is based on agricultural activities, including popcorn growing. The purpose of this study was to evaluate popcorn inbred lines under water stressed (WS) and well-watered (WW) conditions regarding agronomic attributes, root morphology, and leaf “greenness” index (SPAD index), besides investigating the viability of indirect selection by canonical correlations (CC) of grain yield (GY) and popping expansion (PE). Seven agronomic, six morphological root traits were evaluated and SPAD index at five different dates during grain filling. The WS (−29% less water than WW) affected significantly the GY (−55%), PE (−28%), increased the brace and crown root density, and more vertically oriented the brace and crown angles. Higher SPAD index is associated with a higher yield, and these measures were the only ones with no significant genotype × water condition interaction, which may render concomitant selection for WS and WW easier. For associating the corrections of the different traits, CC proved to have better potential than simple correlations. Thus, the evaluation of SPAD index at 29 days after the anthesis showed the best CC, and based on the previous results of SPAD index, may be used regardless of the water condition.

Effect of the year on the vegetative and generative phases in the growing period of maize

2005 ◽  
Vol 53 (2) ◽  
pp. 133-141 ◽  
Author(s):  
L. C. Marton ◽  
T. Szundy ◽  
I. Pók
Keyword(s):  
Diallel Cross ◽  
Grain Filling ◽  
Inbred Lines ◽  
Vegetative Phase ◽  
Late Flowering ◽  
Growing Period ◽  
Dry Conditions ◽  
The Mean ◽  
Selection For ◽  
Generative Phase

The evaluation of an 8 × 8 diallel cross revealed that the mean length of the growing period was the same for inbred lines and their hybrids. However, the vegetative phase was 7-8% shorter and the generative phase 7-8% longer for the hybrids than for the inbred lines. The generative phase of the growing period, unlike the vegetative phase, proved to be extremely variable. Under dry conditions the length of the generative phase was negatively correlated with the length of the vegetative phase. The later a genotype flowered the less time remained for grain filling, due to the stress which curtailed the growing period. The shorter generative phase of late-flowering hybrids was the reason for the weakening of the growing period-yield correlation under dry conditions. This vulnerability of late-flowering hybrids makes selection for stress tolerance particularly important.

Genetic variation in a line of mice selected to its limit for high body weight

1974 ◽  
Vol 19 (3) ◽  
pp. 273-289 ◽  
Author(s):  
W. K. Al-Murrani ◽  
R. C. Roberts
Keyword(s):  
Body Weight ◽  
Genetic Variance ◽  
Genetic Model ◽  
Random Mating ◽  
Inbred Lines ◽  
High Body Weight ◽  
High Body ◽  
Lower Body Weight ◽  
Recessive Genes ◽  
Selection For

SUMMARYA line of mice, at its limit to selection for high body weight did not decline in performance over 11 generations of random mating, neither did it respond when selection was renewed. The experiment tested a method of improving body weight by a scheme which had earlier increased litter size under similar circumstances. The scheme was to derive partially inbred lines from the plateaued line, to select during inbreeding and, finally, to cross the best inbreds. Body weight was not increased, but the study allowed further examination of the residual genetic variance in the line.During inbreeding, the inbred lines became clearly differentiated in body weight, proving that loci controlling body weight had not become fixed. There was also a significant response to selection for a lower body weight during inbreeding. The pattern of results suggested the segregation of recessive genes, detrimental to high body weight but which selection had become inefficient at removing. A genetic model compatible with the results accommodated several such recessives, perhaps as many as 10, each with an effect of about two-thirds of a standard deviation (or some equivalent combination of gene number and effect), and at frequencies of around 0·2. Nevertheless, the total improvement in body weight to be gained by their elimination was only half a gram, or less than 2 %. Thus, substantial genetic effects can occur at individual loci despite trivially low heritabilities and negligible potential gains.

scholarly journals Shoot and Root Traits Contribute to Drought Resistance in Recombinant Inbred Lines of MD 23–24 × SEA 5 of Common Bean

2017 ◽  
Vol 8 ◽  
Author(s):  
Jose Polania ◽  
Idupulapati M. Rao ◽  
Cesar Cajiao ◽  
Miguel Grajales ◽  
Mariela Rivera ◽  
...  
Keyword(s):  
Common Bean ◽  
Drought Resistance ◽  
Recombinant Inbred ◽  
Recombinant Inbred Lines ◽  
Root Traits ◽  
Inbred Lines

scholarly journals Efficiency of crosses selection for yield in red rice through diallel analysis

2021 ◽  
Vol 7 ◽  
pp. 1-10
Author(s):  
Ricardo Montalván Del Águila ◽  
Edson Ferreira Silva
Keyword(s):  
Early Identification ◽  
Genetic Improvement ◽  
Diallel Analysis ◽  
Inbred Lines ◽  
Red Rice ◽  
Self Fertilization ◽  
Selection For ◽  
Selection Of

Diallel analysis is a methodology used in the genetic improvement of plants. One of its main purposes is to provide subsidies for early identification of promising crosses for the development of high yielding inbred lines. Several articles have been published in diallel analysis, and many recommendations were made either for the selection of certain crosses of lines for hybrids or for the development of competitive inbred lines. However, articles about the validation of information predicted by these analyses and the results in the field are scarce or nonexistent. The objective of this article was to validate diallel analysis using model IV of Gardner and Eberhart published in 1966, a methodology recommended to identify promising crosses among developed inbred lines in red rice. We compared the recommendations of the diallel analysis crosses with the process end the result of inbreeding generations. Recommended crosses by the diallel analysis were different from those obtained after generations of self-fertilization and selection. However, two of the four selected parents were matched. Considerations were made about the accuracy of diallel analysis and the need to validate in practice methodologies that theoretically are of great value.

scholarly journals FLOWERING SYNDROME – HYBRID PERFORMANCE RELATIONSHIP IN MAIZE 1- Field traits and growth rates

2016 ◽  
Vol 47 (4) ◽  
Author(s):  
Al- Khazaali & et al.
Keyword(s):  
Grain Yield ◽  
Dry Matter ◽  
Growth Traits ◽  
Block Design ◽  
Inbred Lines ◽  
High Yield ◽  
Late Flowering ◽  
Randomized Block Design ◽  
Four Seasons ◽  
Selection For

In order to identify the role of selection for early and late silking on the inbred lines from Maize (Zea Mays L.) regarding the grain yield of the consequent hybrids. Filed experiment for four seasons (spring and full 2014 and 2015) was conducted in the experimental field of Field Crop Dept., Coll. of Agric., Univ. of Baghdad. Four inbred lines (Zm19, Zm32, Zm51 and Zm61) and two testers (Zm21 late and Zm60 early silking) were used. In the first two seasons, the seeds of the four inbred lines were planted, first 10 plants that flowered early and 10 plants that flowered late were selected and the seeds of the selected plants were multiplied. The seeds of the early and late selected inbred lines were planted in the third season and crossed with testers. Crosses from the early and late flowering were produced and their seeds were cultivated in the last season. Comparison in some field and growth traits were conducted among the crosses. The experiments laid out in completely randomized block design (RCBD) at three replicates. Selection for early and late flowering parents has induced significant differences in days to flowering for all crosses and ranged between 62 days for early parents and 66 days for late parents. Also, significant differences were shown in several traits, the most prominent were crop’s and seed’s growth rate (CGR and SGR ), that correlated with seed filling duration (SFD), which contributed to increase the deposition of the dry matter into the grain for a longer period, which gave a high grain yield (GY). CGR of outstanding crosses ranged from 3.18 to 6.21 g.m-2.day, SGR ranged between 2.3 to 7.3 g. m-2.day, and the SFD between 35-38 days. In parallel, the testers (Zm21 late and Zm60 early silking) have significantly differed in their effect on the traits of some derived crosses, where the results showed significant superiority of the crosses Zm32Zm60 resulted from crossing the tester Zm60 with early silking parents selected from inbred line Zm32 on the crosses Zm32Zm21 resulted from crossing the tester Zm21 with the same parents of Zm32 in the traits of Total Dry Matter (TDM) (1.85 kg.m-2), CGR (18.28 g.m-2.day), Harvest Index (HI) (0.56), and SGR (3.3 g.m-2.day). It can be conclude  that selection for early and late silking inbred lines, as well as the effect of the early and late silking tester have a great importance in deriving hybrids of a high yield and distinct in several traits, which are all significantly contributing in increasing the GY.

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