scholarly journals Theobroma grandiflorum breeding optimization based on repeatability, stability and adaptability information

2021 ◽  
Author(s):  
Saulo Fabrício da Silva Chaves ◽  
Rafael Moysés Alves ◽  
Rodrigo Silva Alves ◽  
Alexandre Magno Sebbenn ◽  
Marcos Deon Vilela de Resende ◽  
...  

The cultivation of Theobroma grandiflorum in the Brazilian Amazon is mainly conducted by family farmers who use a range of different management strategies. Thus, breeding programs of the species must address the challenge of developing cultivars that are adapted to and stable in a variety of cultivation environments. In this context, this study aimed to estimate the optimum number of harvests for genetic selection of T. grandiflorum progenies and identify the most promising ones in terms of productivity, stability, and adaptability. The trials were implemented in three environments, using a randomized complete block design, with 25 full-sib progenies, five replications, and three plants per plot. The traits mean number of fruits/plant, mean fruit production/plant, and rate of infection with witches’ broom (Moniliophthora perniciosa) were evaluated over 11 harvests. The Restricted Maximum Likelihood/Best Linear Unbiased Prediction (REML/BLUP) mixed model method was used to estimate genetic parameters and predict genetic values, which were then applied to assess stability and adaptability. The results show that there is genetic variability among the studied T. grandiflorum progenies and that accurate genetic selection aiming at recombination is effective after three harvests, for recombination, or eleven harvests for identification of recommended progenies. Six progenies were selected that met the requirements for productivity, stability, and adaptability to different cultivation environments. These results can be used to optimize and advance T. grandiflorum breeding programs.

2021 ◽  
Author(s):  
Saulo Fabrício da Silva Chaves ◽  
Rafael Moysés Alves ◽  
Rodrigo Silva Alves ◽  
Alexandre Sebbenn ◽  
Marcos Deon Vilela de Resende ◽  
...  

Abstract The cultivation of Theobroma grandiflorum in the Brazilian Amazon is mainly conducted by family farmers who use a range of different management straegies. Thus, breeding programs of the species must address the challenge of developing cultivars that are adapted to and stable in a variety of cultivation environments. In this context, this study aimed to estimate the optimum number of harvests for genetic selection of T. grandiflorum progenies and identify the most promising ones in terms of productivity, stability, and adaptability. The trials were implemented in three environments, using a randomized complete block design, with 25 full-sib progenies, five replications, and three plants per plot. The traits mean number of fruits/plant, mean fruit production/plant, and rate of infection with witches’ broom (Moniliophthora perniciosa) were evaluated over 11 harvests. The Restricted Maximum Likelihood/Best Linear Unbiased Prediction (REML/BLUP) mixed model method was used to estimate genetic parameters and predict genetic values, which were then applied to assess stability and adaptability. The results show that there is genetic variability among the studied T. grandiflorum progenies and that accurate genetic selection aiming at recombination is effective after three harvests, for recombination, or eleven harvests for identification of recommended progenies. Six progenies were selected that met the requirements for productivity, stability, and adaptability to different cultivation environments. These results can be used to optimize and advance T. grandiflorum breeding programs.


Author(s):  
Geovani S. de Lima ◽  
Francisco W. A. Pinheiro ◽  
Hans R. Gheyi ◽  
Lauriane A. dos A. Soares ◽  
Pedro F. do N. Sousa ◽  
...  

ABSTRACT The objective of this study was to evaluate the effects of saline water irrigation management strategies and potassium doses on the concentration of photosynthetic pigments, gas exchange, and fruit production of ‘BRS GA1’ yellow passion fruit. The experiment was carried out under field conditions using a randomized block design, with treatments based on a 6 × 2 factorial scheme, related to six management strategies for irrigation with saline water (irrigation with low-salinity water throughout the crop cycle-WS; irrigation with high-salinity water in the vegetative stage-VE; flowering stage-FL; fruiting stage-FR; and successively in vegetative/flowering stages-VE/FL and vegetative/fruiting stages-VE/FR) and two doses of potassium (60 and 100% of the recommendation), with four replicates. The dose of 100% recommendation corresponded to 345 g of K2O plant-1 year-1. High electrical conductivity irrigation water (4.0 dS m-1) was used in different phenological stages according to treatment, alternating with water of low electrical conductivity (1.3 dS m-1). The synthesis of chlorophyll a and b, stomatal conductance, instantaneous carboxylation efficiency and water use efficiency of ‘BRS GA1’ yellow passion fruit were reduced under irrigation with water of 4.0 dS m-1 in all strategies adopted. Fertilization with 60% of the K recommendation promoted greater number of fruits and yellow passion fruit yield. Irrigation with 4.0 dS m-1 water in the vegetative/flowering and flowering stages reduced the yield of yellow passion fruit.


2017 ◽  
Vol 47 (3) ◽  
pp. 175-184 ◽  
Author(s):  
Rafael Moysés ALVES ◽  
Carlos Rogério de Sousa SILVA ◽  
Paulo Sérgio Bevilaqua de ALBUQUERQUE ◽  
Vinicius Silva dos SANTOS

ABSTRACT The expansion of the genetic base of cultivated materials is an ongoing activity of the cupuassu (Theobroma grandiflorum) breeding program. However, the parents involved need to be genotypically and phenotypically characterized to ensure compatibility of crossings, as well as to assist in the selection of more promising individuals for hybridization. This study aimed to identify and select T. grandiflorum clones that are compatible and genetically divergent using tools such as the estimates of genotypic, phenotypic, and combined distances, as well as the compatibility rates among clones. The genetic distance analysis of the clones was performed with 14 heterologous microsatellite primers of cocoa (Theobroma cacao) that amplify the DNA of cupuassu. Phenotypic characterization was based on 14 variables related to fruit production. The joint dissimilarity matrix was obtained by means of the sum of the phenotypic and molecular dissimilarity matrices. The intra- and inter-clonal compatibility was estimated through controlled crossings. A low correlation was noted between the dissimilarity matrices based on the molecular and agronomic data. As for compatibility, all clones were self-incompatible, with different compatibility rates when crossed. The compatibility index was strongly influenced by the degree of relationship of the clones. It was possible to identify and select the most promising sets of cupuassu clones to be used in breeding programs, despite their genetic relationship.


2017 ◽  
pp. 31-43
Author(s):  
Berta Ratilla ◽  
Loreme Cagande ◽  
Othello Capuno

Organic farming is one of the management strategies that improve productivity of marginal uplands. The study aimed to: (1) evaluate effects of various organic-based fertilizers on the growth and yield of corn; (2) determine the appropriate combination for optimum yield; and (3) assess changes on the soil physical and chemical properties. Experiment was laid out in Randomized Complete Block Design, with 3 replications and 7 treatments, namely; T0=(0-0-0); T1=1t ha-1 Evans + 45-30-30kg N, P2O5, K2O ha-1; T2=t ha-1 Wellgrow + 45-30-30kg N, P2O5, K2O ha-1; T3=15t ha-1 chicken dung; T4=10t ha-1 chicken dung + 45-30-30kg N, P2O5, K2O ha-1; T5=15t ha-1 Vermicast; and T6=10t ha-1 Vermicast + 45-30-30kg N, P2O5, K2O ha-1. Application of organic-based fertilizers with or without inorganic fertilizers promoted growth of corn than the control. But due to high infestation of corn silk beetle(Monolepta bifasciata Horns), its grain yield was greatly affected. In the second cropping, except for Evans, any of these fertilizers applied alone or combined with 45-30-30kg N, P2O5, K2O ha-1 appeared appropriate in increasing corn earyield. Soil physical and chemical properties changed with addition of organic fertilizers. While bulk density decreased irrespective of treatments, pH, total N, available P and exchangeable K generally increased more with chicken dung application.


Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 533
Author(s):  
Fernanda Zatti Barreto ◽  
Thiago Willian Almeida Balsalobre ◽  
Roberto Giacomini Chapola ◽  
Antonio Augusto Franco Garcia ◽  
Anete Pereira Souza ◽  
...  

Sugarcane breeding programs require 15 years of experimentation to create more productive cultivars, and estimates of genetic progress can indicate the efficiency of breeding programs. In this study, we used a diversity panel, the Brazilian Panel of Sugarcane Genotypes (BPSG), with the following objectives: (i) to estimate, through a mixed model, the adjusted means and genetic parameters of ten traits evaluated over three harvest years; (ii) to estimate genotypic correlation among those traits; and (iii) to estimate genetic progress over six decades of breeding. The heritabilities ranged from 0.43 to 0.88, and we detected 42 significant correlations, 9 negative and 33 positive. Over six decades, the sucrose-related traits BRIX, POL%C, and POL%J showed an average increase per decade of 0.27 °Brix (0.26% and 0.31%, respectively). Stalk number, height, and weight of the plot, and cane and sucrose yields revealed average increases per decade of 3.27 stalks, 0.06 m, 9.42 kg, 11.22 t/ha, and 2.08 t/ha, respectively. The genetic progress of the main agronomic traits is discussed through a historical series of sugarcane genotypes present in the BPSG. The findings of this study could contribute to the management of new breeding strategies and allow for future studies of associative mapping.


2015 ◽  
Vol 28 (3) ◽  
pp. 230-238 ◽  
Author(s):  
PHILIPE LIMA DE AMORIM ◽  
JANAINA AZEVEDO MARTUSCELLO ◽  
JOSÉ TEODORICO DE ARAÚJO FILHO ◽  
DANIEL DE NORONHA FIGUEIREDO VIEIRA DA CUNHA ◽  
LIANA JANK

ABSTRACT: Cultivars of the genus Nopalea are known in Brazil for being tolerant to cochineal carmine attacks, thus making the cultivation of this genus a promising alternative for mitigating the negative effects of this insect on the production of biomass. With the objectives of characterizing morphologically spineless forage cactus varieties and identify morphological characteristics that may be the focus in spineless forage cactus breeding programs, an experiment was conducted in a completely randomized block design with 11 treatments and four replications. The variety Alagoas showed the highest values of weight, area and volume of cladodes. The varieties Negro Michoacan F7 and V7, Tamazunchale V12 showed the highest values of the cladode area index, the total volume of cladodes and total fresh mass production. The varieties Negro Michoacan V7 and F7 presented the highest water use efficiency and dry mass yield. Cladode volume showed the highest correlation coefficients with the fresh weight of cladodes. Aiming the release of varieties for biomass production, varieties Negro Michoacan F7, V7 and Tamazunchale V12 may substitute the Miúda variety. The number and cladode area index may be used as criteria for selection of superior varieties in breeding programs.


Plant Disease ◽  
2019 ◽  
Vol 103 (6) ◽  
pp. 1189-1195 ◽  
Author(s):  
Joseph Opoku ◽  
Nathan M. Kleczewski ◽  
Kelly A. Hamby ◽  
D. Ames Herbert ◽  
Sean Malone ◽  
...  

Brown marmorated stink bug (Halyomorpha halys Stål) is an invasive agricultural pest that causes severe damage to many crops. To determine potential associations between H. halys feeding damage, Fusarium infection, and mycotoxin contamination in field corn, a field survey was conducted in eight counties in Virginia. Results indicated an association between H. halys feeding damage and fumonisin contamination. Subsequent field experiments in Delaware, Maryland, and Virginia examined the ability of H. halys to increase Fusarium verticillioides (Sacc.) Nirenberg infection and fumonisin concentrations in corn. At the milk stage, H. halys (0 or 4 adults) and Fusarium (with or without F. verticillioides inoculum) treatments were applied to bagged ears in a two by two factorial randomized complete block design with 12 replicates. H. halys treatments increased levels of feeding damage (P < 0.0001) and Fusarium infection (P = 0.0380). Interaction between H. halys and Fusarium treatments influenced severity of infection (P = 0.0018) and fumonisin concentrations (P = 0.0360). Results suggest H. halys has the ability to increase both Fusarium infection and fumonisin concentrations in field corn. Further studies are needed to understand mechanisms by which H. halys increases fumonisin and to develop management strategies to mitigate impacts of H. halys on field corn in the region.


2003 ◽  
Vol 21 (3) ◽  
pp. 443-447 ◽  
Author(s):  
Márcio S. de Lima ◽  
Antonio I. I. Cardoso ◽  
Marcelo F. Verdial

Squash seeds yield and quality can be improved by proper population plant spacing and the pollen quantity, which influences the pollination quality and fertilization. Nine experiments were conducted as a factorial combination of three spacing between plants (0.8 x 0.3, 0.8 x 0.6 and 0.8 x 0.9 m), two quantities of pollen (50% of an anther and another entire one) and natural insect pollination. Seed and fruit production parameters, and seed quality were evaluated. A randomized complete block design, five replications, with ten plants per plot was adopted. Larger plant spacing increased the average number of mature fruits and seed yield per plant. Seed yield was directly proportional to the amount of pollen used during pollination. Higher amounts of pollen resulted in higher seed yield per area, but the plant spacing did not affect this characteristic. Manual pollination, using a whole anther, did not differ from natural pollination in relation to seed yield and quality.


2011 ◽  
Vol 29 (4) ◽  
pp. 600-604 ◽  
Author(s):  
Damiana Cleuma de Medeiros ◽  
José Francismar de Medeiros ◽  
Francisco Aécio de L Pereira ◽  
Sonally Cristina de M Silva ◽  
Maria das Graças Amâncio

Among the problems faced by the melon crop in the state of Rio Grande do Norte, northeastern Brazil, the effect of water and soil salinity is considered one of the key factors to limit fruit production and quality. The aim of this work was to study the effects of using irrigation waters with different salinity levels on yield and quality of fruits of the yellow melon hybrid Mandacaru. A randomized complete block design was used with five treatments (irrigation water salt concentrations: 0.54, 1.48, 2.02, 3.03, 3.9 dS m-1) and four replications. The effects of these concentrations were evaluated through, number of marketable fruits per plant, marketable and total fruit yield, average marketable fruit mass, soluble solids content and pulp firmness. Increment in water salinity level negatively influenced crop yield. The 3.9 dS m-1 salinity level caused yield losses of 20.31%, due to the reduction of fruit number per plant. The highest soluble solid content and the highest pulp firmness values were estimated to occur at salinity levels 2.09 and 3.5 dS m-1, respectively.


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