Functional Plant Breeding Journal

SELECTION OF PEACH GENOTYPES WITH LOW CHILLING REQUIREMENTS VIA MIXED MODELS

Marina Martinello Back — 2023-04-25

A good selection of genotypes that show proper stability and adaptability in the characters of interest is crucial to obtaining elite cultivars. In this way, the objective of this work was to study, via mixed models, the performance of advanced selections of peach trees with low chilling requirements. Sixteen advanced peach selections from the EPAGRI Drupaceae breeding program were evaluated during three crops (2017, 2018, and 2019) and at two sites with different altitudes (220 m and 360 m). The characters evaluated were: yield (t.ha-1), maturation cycle (days), average fruit mass (g), soluble solids (°BRIX), and titratable acidity (%). They were analyzed via mixed models that use variance estimates obtained by the REML method (restricted maximum likelihood) by the SELEGEN – REML/BLUP program. Several genotypes showed good performance for the assessed characteristics, where sel. 0574 stood out as it obtained a good yield, high sugar content, and a good sugar/acidity ratio. Selections 0184, 0574, 0374, and 0791 present better performances for fruit yield, such as stability and adaptability (HMGV, RPGN, and HMRPGN). For the traits yield and average fruit mass, the effects of the environment do not change the behavior of the selections, making the genotypes representative of the region of interest.

BRS FS313: JALO TYPE COMMON BEAN CULTIVAR WITH LARGE BEANS AND HIGH YIELD

Marcelo Sfeir Aguiar — 2023-04-25

BRS FS313 is a common bean cultivar with high yield (3,200 kg.ha-1), jalo type bean grain, and greater 100-seed weight (50 g). It has a semi-early cycle, semi-upright plant architecture, and resistance to anthracnose and to root rots. BRS FS313 is recommended for the Central and South-Central regions of Brazil

MORPHO-AGRONOMIC GENETIC DIVERSITY IN COMMON BEAN LANDRACES BASED ON BLUP VALUES

César Pedro — 2023-04-25

The objective of the research was to evaluate morpho-agronomic of genetic diversity in common bean landraces based in predicted genotypic values, to identify divergent genotypes with agronomic potential in several traits for selection activities and crosses in the breeding program. Traits evaluated were plant height, branches per plant, days to flowering, days to maturity, pods per plant, seeds per pod, seeds mass and grain yield at Nampula Research Station, Mozambique, in an augmented design with four blocks, 27 genotypes (24 landraces and 3 checks). Data were subjected to analysis of deviance, variance components and genetic parameters. The genotypic values were estimated by REML/BLUP mixed model and were used in heat map clustering, pairwise distances and constellation plot. The results indicated genetic variability for all traits except branches per plant and showed six clusters of divergent genotypes. Days to flowering, pods per plant and plant height, had the highest contribution to genetic divergence. The morpho-agronomic analysis of genetic diversity in common bean landraces based in predicted genotypic values allowed to identify divergent genotypes with agronomic potential in several traits for selection activities and crosses in the breeding program

SELECTION BETWEEN WATERMELON (CITRULLUS LANATUS) ACCESSIONS VIA THEIR ASSOCIATED MICROBIOTA

Rania Aydi-Ben-Abdallah — 2023-04-25

Microbiome engineering, which can improve the functional capabilities of native microbial species under challenging agricultural ambiance, is an emerging biotechnological strategy to improve crop yield and resilience against biotic and abiotic environmental constraints. In this study, the microbial community structure in the rhizosphere of 7 watermelon accessions was monitored using the soil dilution plating technique on specific media. All accessions tested were screened for their root growth before planting to select accessions with an improved root system. The fruit production was determined at four months post-planting. The total soluble solids (TSS) content was measured on flesh of sampled fruits. The dendrogram of hierarchical ascending classification clustered watermelon accessions into two main groups. The 1st cluster comprised two accessions P1 and P8 which were characterized by the highest abundance of actinomycetes and Aspergillus spp. communities in their rhizopshere, the highest weight of fruits with sweet taste. The current study clearly demonstrated that the soil microbial community structure has been shaped by Citrullus lanatus accessions. Future watermelon breeding programs will be focused on the selection of accessions that are quite able to exploit these associated beneficial microbial communities for enhanced growth and improved resistance to associated biotic stresses.

PERFORMANCE OF EARLY-CYCLE SOYBEAN GENOTYPES FOR USE IN A SUGARCANE ROTATION SYSTEM

Julia Godoy Alexandrino — 2023-04-25

Sugarcane and soybean are relevant crops for Brazilian agribusiness, and the demand for their products and by-products is growing worldwide. The Soybean x Sugarcane (SSC) production system operates with high efficiency and contributes to the sustainability of agribusiness. Soybean cultivars suitable for use in SSC must have an early cycle, adaptation to the edaphoclimatic region, and high yield. The Value of Cultivation and Use (VCU) assays are conducted in different edaphoclimatic regions, to identify promising soybean genotypes in an advanced stage of inbreeding. The objective of this work was to identify soybean genotypes with high adaptability and stability that are possible candidates for registration and protection of new commercial cultivars, for use in the SSC system in the São Paulo State, Brazil. Twenty genotypes and four commercial cultivars were evaluated in six environments, in a randomized block design with three replications. To verify adaptability and stability, the AMMI method was used. Using the adopted methodology, it was possible to identify superior genotypes for SSC that showed good adaptability and general stability between the evaluated environments, being possible recommendable candidates for SSC in the edaphoclimatic regions in which they were evaluated.

COMBINING ABILITIES OF SPRING WHEAT (Triticum aestivum L.) FOR GRAIN YIELD AND RELATED TRAITS

Md. Jakir Mahmud — 2023-04-25

An 8 x 8 F 2 spring wheat (Triticum aestivum L.) half diallel population with respective parents was assessed in a field trial at the field laboratory of the department of genetics and plant breeding at the Bangladesh Agricultural University, Mymensingh, during the period from November 2016 to April 2017, following a randomized complete block design (RCBD). The research objectives were to discover the combining abilities of grain yield and its associated traits. Significant variations among the genotypes were observed for different traits viz., number of spikes plant-1, length of spike (cm), number of spikelets spike-1, plant height (cm), straw grain weight (gm), number of grains spike-1, 1000 grain weight (gm), yield plant-1 (gm), harvest index (%), and grain yield in hectare. The genetic analysis following Griffing’s approach revealed significant additive and non-additive gene actions, with a preponderance of both additive and non-additive genetic components for regulating different traits. For grain yield plant-1 BARI Gom 27 and Kheri were observed as the best general combiners whereas BARI Gom 21 × BARI Gom 27 and Kheri × BARI Gom 30 exhibited as the best heterotic patterns. All of the traits investigated had a significant positive correlation with yield plant-1. BARI Gom 21 × BARI Gom 27 and Kheri × BARI Gom 30 were the top yielding cross combinations on the basis of combining ability among the studied genotypes. Those cross combinations may be used for hybrid crop development or to extract transgressive segregants in developing high-yielding bread wheat cultivars.

INTRAPOPULATION RECURRENT SELECTION STRATEGIES IN PLANT BREEDING

Magno Antonio Patto Ramalho — 2023-04-25

The conduction of each intrapopulation recurrent selection (IRS) cycle typically requires a few years. There are several factors, with and without the control of plant breeders, that affect the success obtained with the IRS. For it to be more efficient, such factors must be judiciously assessed. In this light, this study aimed to compare a large number of variables involved in the efficiency of the IRS. Selection gain (SG) estimates with the IRS were obtained. Considering different variables under the control of the breeders such as the following: two types of progenies, half-sib (HS) and full-sib (FS); three experiment evaluation conduction strategies with multiple tree plots (MTP), single tree plots (STP), and clonal progeny test (CPT), and other variables. Variables without the control of plant breeders were also considered: mean allele frequencies of the populations (p); level of dominance (d/a); broad-sense heritability at the individual level (h²). Over 3000 SG estimates were obtained. When the CPT was used, the SG was always higher than that obtained with STP or MTP; the SG when employing HS was always higher than with FS. However, the employment of HS, especially when using clones for the recombination, has the serious restriction of not allowing higher selection intensities and maintaining the same number of progenies in the different IRS calculations. In this context, the employment of FS is more advisable since it allows applying a more significant selection intensity and enables more homogeneous recombination.

ADAPTABILITY AND PHENOTYPIC STABILITY OF UPLAND RICE GENOTYPES IN MOZAMBIQUE

Alcides Mário Charimba — 2023-04-25

The alternative adopted in rice (Oryza sativa L.) breeding programs to decrease the effect of genotype x environment to reduce the effect of the interaction of genotype x environment (G x E), consists in the evaluation of genotypes in different environments and years, for an accurate recommendation of the most stable and adapted genotypes. Therefore, the objective of this work was to evaluate the phenotypic adaptability and stability of the productive upland rice genotypes in Mozambique, using the graphical tool for data analysis, the GGE biplot. We used data on grain yield, derived from the evaluation of five upland rice genotypes from the Rice Genetic Improvement Program of the Institute of Agrarian Research from Mozambique - Northeastern, Zonal Center (IIAM-CZnd). The trials were conducted in the complete block design with four repetitions in the agricultural years 2019/2020, 2020/2021, and 2021/2022. The trials were conducted in a total of five environments divided into three agricultural years, located in northern Mozambique. It was concluded from this work that genotypes G4 and G2 were superior to the overall average for productivity and genotype G3 showed high stability. The genotype G4 can be recommended for all mega-environments, for presenting good adaptability and phenotypic stability.

PHENOTYPIC, GENETIC, AND ENVIRONMENTAL CORRELATIONS IN S1 PROGENIES OF LANDRACE MAIZE

Mauricio Ferrari — 2023-04-26

Maize (Zea mays L.) belongs to the Poaceae family and stands out among the most cultivated cereals worldwide because of its great economic and social importance. This study aims to estimate and identify phenotypic, genetic, and environmental associations in S 1 maize progenies from the southern Rio Grande do Sul landrace populations. The experimental design was the augmented blocks, with ten S1 progenies groups, and two commercial controls, the simple cross hybrids Pioneer 30F53 and Agroeste 1590, allocated in four repetitions. The S1 progenies were obtained after self-fertilization of random plants in the maize landrace populations, being them: Amarelão, Argentino Branco, Argentino Amarelo, Branco Vermelho Indio, Branco Oito Carreiras, Caiano Rajado, Cateto Branco, Criolão and Dente de Ouro, and the open pollinated variety BRS Planalto. The S 1 progenies present specific genetic and phenotypic correlations in both senses and magnitudes, becoming difficult to define strategies for indirect selection based on correlation between traits. Spike length presents strong and positive genetic and phenotypic correlation with spike mass and may be used for indirect selection of S 1 progenies with greater spike mass, regardless of the origin of the progeny.Positive phenotypic and genotypic correlations of intermediate magnitudes were verified between spike diameter and grain depth, which are similar for all progenies. Plant height reveals strong and positive phenotypic and genetic associations with spike insertion height, however, this trait did not steadily correlate with grain yield.The environmental correlations present significant effects of the phenotypes expression of S1 progenies produced in the southern Rio Grande do Sul.