scholarly journals Studies of Genetic Variability, Heritability and Genetic Gain for Some Important Horticultural Traits in Cauliflower (Brassica oleracea var. botrytis L.)

2018 ◽  
Vol 7 (04) ◽  
pp. 82-92
Author(s):  
Subhrajyoti Chatterjee ◽  
Debmala Mukherjee ◽  
Omkar Aralikatti ◽  
Sumit Patil ◽  
Hardyal Singh Kanwar ◽  
...  
Keyword(s):  
Genetic Variability ◽  
Brassica Oleracea ◽  
Genetic Gain ◽  
Horticultural Traits

scholarly journals Predicting the genetic gain in the Brazilian white maize landrace

2009 ◽  
Vol 39 (1) ◽  
pp. 19-24 ◽  
Author(s):  
Ana Raquel Ribeiro e Souza ◽  
Glauco Vieira Miranda ◽  
Messias Gonzaga Pereira ◽  
Leandro Vagno de Souza
Keyword(s):  
Genetic Variability ◽  
Grain Yield ◽  
Genetic Gain ◽  
Plant Density ◽  
Production Systems ◽  
Agronomic Traits ◽  
Minas Gerais ◽  
Phenotypic Variance ◽  
Environment Interaction ◽  
Maize Landrace

The objectives of this research were to evaluate the genetic variability and predict genetic gain in the white maize landrace rescued in Barbacena, Minas Gerais, Brazil. The Brazilian maize landraces have economic and social importance for certain areas in Brazil, and research on this germplasm is very important for local food security. Three experiments were carried out with 100 half-sib progenies, in Campos dos Goytacazes, RJ, Coimbra and Barbacena, Minas Gerais, Brazil. These sites were chosen for their soil and climatic differences. An analysis of variance was significant among the progeny for all characters, indicating the presence of genetic variability between the three populations. In Campos dos Goytacazes and Coimbra, the genetic variation of the white maize landrace was responsible for most of the phenotypic variance in grain yield and can be used in selection cycles. There was no significant genetic variance in grain yield in Barbacena. For the white maize landrace it was concluded that: the characters of the component of productivity such as plant density and number of plants with kernels can produce indirect genetic gain for grain yield and are suitable for breeding; prebreeding of the maize landrace is necessary before being used directly in the elite germplasm; the population contains high genetic variability and opportunities for genetic gain; the average agronomic traits are suitable only for traditional production systems with few inputs, and polyculture; the difference between environments produces specific responses in the progeny i.e. there is a progeny x environment interaction.

Genetic Variability for Pod Yield and Component Traits in Sugar Snaps (Pisum sativum var. saccharatum)

2020 ◽  
Author(s):  
Ajay Chauhan ◽  
Akhilesh Sharma ◽  
Parveen Sharma ◽  
Viveka Katoch ◽  
Sanjay Chadha ◽  
...  
Keyword(s):  
Genetic Variability ◽  
Block Design ◽  
Internodal Length ◽  
Breeding Lines ◽  
Pod Yield ◽  
Horticultural Traits ◽  
Component Traits ◽  
Additive Gene ◽  
High Heritability ◽  
Positive Direct

Background: Edible podded pea is an oriental vegetable crop which shares the cultivation pattern with the garden pea. Fresh tender pods lacking parchment layer are consumed whole like beans. It is a newly introduced crop in India and therefore, it would be imperative to identify the most promising genotypes vis-à-vis traits of interest, those contributing towards maximization of yield. The present investigation was, therefore, planned to assess the genetic parameters of variability for pod yield and related horticultural traits in order to identify the most promising edible pod pea genotypesMethods: Thirty six genotypes comprising of 29 F7 advanced breeding lines and nine lines from different institutes including three checks namely, ‘Arka Apoorva’, ‘Arka Sampoorna’ and ‘Mithi Phali’ were evaluated in randomized complete block design over three replications during winters 2016-2017 at C.S.K. Himachal Pradesh Krishi Vishvavidyalaya, Palampur for pod yield and related horticultural traits.Result: Sufficient genetic variability was observed for all morphological and yield contributing attributes. The magnitude of phenotypic (PCV) and genotypic (GCV) coefficients of variation were high for pod yield while branches per plant, internodal length, harvest duration and pods per plant showed high PCV and moderate GCV. High heritability along with high genetic advance was observed for internodal length, plant height, average pod weight and pod yield per plant indicating the importance of additive gene action. Pod yield per plant revealed positive correlation at both phenotypic and genotypic levels with pods per plant, average pod weight, pod length and pod breadth. Pods per plant and average pod weight at both phenotypic and genotypic levels had maximum positive direct and indirect effects to the total association of component traits suggesting the importance of these traits towards pod yield. 

scholarly journals Heterosis for Horticultural Traits in Broccoli

HortScience ◽  
2006 ◽  
Vol 41 (4) ◽  
pp. 990C-990
Author(s):  
Anna L. Hale ◽  
Mark W. Farnham
Keyword(s):  
Brassica Oleracea ◽  
Plant Height ◽  
Inbred Lines ◽  
Stem Diameter ◽  
Hybrid Vigor ◽  
Plant Vigor ◽  
Horticultural Traits ◽  
Predominant Type ◽  
Head Weight ◽  
Almost All

Over the last 3 decades, broccoli (Brassica oleracea L., Italica Group) hybrids made by crossing two inbred lines replaced open-pollinated populations to become the predominant type of cultivar. The change to hybrids evolved with little or no understanding of heterosis or hybrid vigor in this crop. Therefore, the purpose of the present study was to determine levels of heterosis expressed by a set of hybrids derived by crossing relatively elite, modern inbreds (n = 9). A total of 36 hybrids formed by crossing nine parents were evaluated for horticultural characters, including head weight, head stem diameter, plant height, plant width (in a row), and maturity (e.g., days from transplant to harvest) in four environments. When averaged across all four environments, roughly half of the hybrids exhibited high parent heterosis for head weight (1 to 30 g) and stem diameter (0.2 to 3.5 cm). Almost all hybrids showed high parent heterosis for plant height (1 to 10 cm) and width (2 to 13 cm). Unlike other traits, there was negative heterosis for maturity, indicating that heterosis for this character in hybrids is expressed as earliness. With modern broccoli inbreds, heterosis for head characteristics appears less important than for traits that measure plant vigor.

Studies of Genetic Variability of Tomato (Solanum lycopersicum L.) Hybrids under Protected Environment

2021 ◽  
Vol 12 (5) ◽  
pp. 264-270
Author(s):  
Kanchhi Maya Waiba ◽  
◽  
Parveen Sharma ◽  
Kasi Indra Kumar ◽  
Shivani Chauhan ◽  
...  
Keyword(s):  
Genetic Variability ◽  
Block Design ◽  
Himachal Pradesh ◽  
Climatic Zones ◽  
Hybrid Combination ◽  
Solanum Lycopersicum L ◽  
Horticultural Traits ◽  
Randomized Complete Block Design ◽  
The Mean ◽  
The One

A study was conducted to estimate genetic variability among horticultural traits and to evaluate these hybrids for protected environmental cultivation during spring-summer season, 2019 (April-September). Twelve hybrids of tomato were evaluated under modified naturally ventilated poly-house at the Vegetable Research Farm, Department of Vegetable Science and Floriculture, Chaudhary Sarwan Kumar Himachal Pradesh Krishi Vishvavidyalaya following Randomized Complete Block Design (RBD) with three replications, Palampur, Himachal Pradesh, India. Based on the mean performance, hybrid CLN2126×CLN1314G was found promising for yield plant-1 (4.37 kg) yield m-2 area (26.24 kg), TSS (6.53 °B), days to 50% flowering (26.66 days), days to first picking (67.33 days), number of fruits per plant (64.01), inter-nodal length (17.71 cm), number of nodes plant-1 (16.70 nodes) and plant height 316.87 cm). So, an ideal plant type producing a higher yield per plant will be the one having traits like a higher number of fruits per plant, and lesser days to first picking. It is concluded that the hybrid combination CLN2126×CLN1314G is promising for these traits. This can be included for multi-locational testing in different agro-climatic zones of Himachal Pradesh under protected environment.

scholarly journals TENDÊNCIA DOS EFEITOS GENÉTICOS DIRETOS E MATERNOS DO PESO A DESMAMA DE BOVINOS DA RAÇA NELORE MOCHA NA REGIÃO PECUÁRIA CAMPO GRANDE E DOURADOS – MATO GROSSO DO SUL

2003 ◽  
Vol 8 (1) ◽  
Author(s):  
F.Q. GARCIA ◽  
P.B. FERRAZ FILHO ◽  
J.C. SOUZA ◽  
L.O.C. SILVA
Keyword(s):  
Animal Models ◽  
Genetic Variability ◽  
Maternal Effects ◽  
Maternal Effect ◽  
Genetic Gain ◽  
Fixed Effects ◽  
Mato Grosso ◽  
Abstract Data ◽  
Mato Grosso Do Sul ◽  
Genetic Trends

Dados relativos a 2891 observações de pesos de animais da raça Nelore Mocha, nascidos e criados na região pecuária Campo Grande - Dourados, no Estado de Mato Grosso do Sul, no período de 1975 a 1996, foram analisados com o objetivo de avaliar as mudanças genéticas aditivas diretas e maternas, dos pesos à desmama, padronizados para os 205 (P205) dias de idade. A tendência genética foi estimada pela regressão ponderada das médias anuais dos valores genéticos (aditivo e materno) sobre o ano de nascimento do animal. As estimativas dos componentes de (co) variância utilizadas para o cálculo dos valores genéticos, foram obtidas pelo método de máxima verossimilhança restrita livre de derivadas (REML), usando o aplicativo MTDFREML (sob modelo acima). No modelo foram incluídos os efeitos aleatórios aditivo direto e materno, além dos efeitos fixos de grupo de contemporâneos (fazenda, sexo, estação e ano de nascimento do animal) e a covariável idade da vaca ao parto (efeitos linear e quadrático). As tendências genéticas estimadas dos efeitos diretos e maternos foram 0,78 kg/ano e – 0,35 kg/ano, respectivamente. A evolução do ganho genético oriundo do efeito aditivo direto foi de -0,51 a 2,14 kg/ano, resultando em uma amplitude de 0,1262 kg/ano, e a mesma medida da dispersão da tendência genética do efeito materno foi de -0,0611 kg/ano, conseqüente de uma de variação de 0,27 a -1,02 kg/ano no período estudado. Considerando a variabilidade genética existente nos rebanhos da região, os resultados observados estão bem aquém das mudanças possíveis. Tendency of the direct and maternal genetic effects on the weight at the weaning of Nelore bovines at the cattle raising region of Campo Grande and Dourados Abstract Data related to 2891 observations of weights of Nelore Polled breed, borned and servants in the region of Campo Grande - Dourados, in the state of South Mato Grosso, in the period from 1975 to 1996, were analyzed with the objective of evaluating the direct and maternal addictive genetic trends. The weights were standardized for the 205 (P205) days of age. The genetic trends were dear for the pondered regression of the annual averages of the genetic values (addictive and maternal) on the year of birth of the animal. The estimates of the components of (co) variance used for the calculation of the genetic values, were obtained by the method of maximum restricted verisimilitude free from having derived (REML), using the application MTDFREML (animal models) contends direct and maternal addictive aleatory effects, besides the fixed effects of contemporaries’ group (farm, sex, season and weight of the animal) and the co-variable age of the cow to the childbirth (lineal and quadratic). The esteemed genetic trends of the direct and maternal effects were 0,78 kg/ year and - 0,35 kg/year, respectively. The evolution of the genetic gain originating from of the direct addictive effect was from -0,51 to 2,14 kg/year, resulting in a width of 0,1262 kg/year, and the same measure of the dispersion of the genetic trends of the maternal effect was of -0,0611 kg/year, as a consequence from a variation of 0,27 to -1,02 kg/year in the period. Considering the existent genetic variability in the region, the observed results are bellow possible changes.

Effect of controlling future rate of inbreeding on expected genetic gain and genetic variability in small livestock populations

2020 ◽  
Vol 60 (14) ◽  
pp. 1681
Author(s):  
S. I. Mwangi ◽  
T. K. Muasya ◽  
E. D. Ilatsia ◽  
A. K. Kahi
Keyword(s):  
Genetic Variability ◽  
Milk Yield ◽  
Genetic Gain ◽  
Genetic Relationships ◽  
Breeding Population ◽  
Breeding Values ◽  
Sahiwal Cows ◽  
Improvement Programs ◽  
Small Livestock ◽  
Estimated Breeding Values

Context In the present study we assessed the use of average relationship as a means to control future rates of inbreeding in small cattle closed nucleus and its effect on genetic gain for milk yield as a means of managing genetic variability in livestock improvement programs. Aim The aim was to strike an ideal balance between genetic gain and loss of genetic variability for Sahiwal population. Methods A total of 8452 milk yield records of Sahiwal cows from National Sahiwal Stud, Kenya, were used to estimate breeding values and 19315 records used to estimate average relatedness of all individuals. The estimated breeding values and genetic relationships were then used to optimise individual genetic contributions between the best two males and the top 210 females in 2000–2008-year group, as well as between the best four, six and eight males and top, 420, 630 and 840 females based on estimated breeding values for lactation milk yield. Weights on genetic merit and average relationship considered in this study were (1, 0), (1, −300), (1, −500), (1, −1000) and (0, −1). Key results When the best sires were selected and used for mating disregarding average relationship with their mates i.e. (0, –1), genetic gain of up to 213 kg was realised accompanied by a rate of inbreeding per generation of 4%. Restricting average relationship alone i.e. (0, –1), resulted in a future rate of inbreeding of 1.6% and average merit of 154 when top two sires were used for breeding. At the same restriction level but using eight top sires, the rate of inbreeding per generation was 0.9% accompanied by an average merit of 128.2 kg. Controlling average relationship between mates resulted in increased genetic variability i.e. lower rate of inbreeding though average merit declined. Conclusion A rate of inbreeding per generation of <1% is required for a population to maintain its long-term viability. For this level to be attained, the size of the breeding population should be increased from the current two sires vs 210 dams to eight sires vs 840 dams. Implications Practical implications for closed nucleus programs such as the Sahiwal program in Kenya should include expanding the nucleus to comprise other institutional and privately-owned herds.

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