Coffee breeding based on root traits is important to identify productive genotypes under adverse environmental conditions. This study assessed the diversity of root traits in Coffea canephora and its correlation with plant height and crop yield. Undisturbed soil samples were collected down to 60 cm from 43 coffee genotypes, in which one of them was propagated by seed and all others by stem cutting. The roots were washed, scanned, and processed to quantify root length density, root volume, root superficial area, and root diameter. Additionally, plant height and crop yield were also assessed. Root length density ranged from 40 to 1411 mm cm−3, root volume from 6 to 443 mm3 cm−3, root superficial area from 61 to 1880 mm2 cm−3, and root diameter from 0.6 to 1.1 mm. Roots were concentrated in the topsoil (0–20 cm) for most genotypes. In deeper depths (30–60 cm), root length density, root volume, and root superficial area were higher in genotypes 14, 25, 31, and 32. Positive correlations were found between root traits and both plant height and crop yield. The results of this work may contribute to the overall cultivation of C. canephora, specially for crop breeding in adverse environmental conditions.
Coffee genotypes cultivated in the Amazonian region have been gaining increasing prominence in Brazilian plantations. This study aimed to quantify nutrient accumulation in the fruits, grains, and husks of Robusta coffee genotypes cultivated in the Brazilian Amazon and estimate genetic diversity. The experiment was conducted in Alta Floresta D’Oeste—Rondônia, Brazil. To assess nutrient accumulation, fresh fruits were collected. These were dried, processed, separated into grains and husks, and subjected to chemical analysis. Nutrient accumulation in fruits, grains, and husks, as well as the grain/husk ratio, underwent analysis of variance through the F-test (p < 0.01. For each evaluated trait, the experimental coefficient of 337 variation (CVe), genetic coefficient of variation (CVg), and genotypic determination coefficient (H2) were also estimated. Variability was observed among Robusta coffee genotypes, with VP06, AS4, and AS10 being the most dissimilar. LB080 had the lowest dry fruit weight and the lowest percentage of grains in relation to husks. ZD156 accumulated more K in the grains, while VP06 and AS10 were the genotypes that accumulated more nutrients in the husks. Nutrients N, K, Ca, and P are accumulated in larger quantities, necessitating the calibration of mineral fertilization dosages and distribution.
This work aimed to evaluate the variability in the distribution of the root system among genotypes of C. canephora cv. Conilon and indicate management strategies for a more efficient mineral fertilization. Root distribution was evaluated in six genotypes. The experimental design was in randomized blocks with three replications. Soil monoliths measuring about 27 cm3 were collected at six different soil depths, at three row distances and nine distances of inter-row planting. The collections were carried out in one plant of each repetition. In total, 1296 samples were evaluated. The roots were washed, digitized and processed to quantify length density, volume, surface area and diameter. The distribution of the root system was characterized using semivariograms. It was observed that the highest concentration of roots occurred in the distances close to the irrigation drippers. There was variation in the distribution of the root system among the genotypes. However, in general, the root system is concentrated at a depth of 0 to 20 cm in the soil, at distances up to 50 cm in the planting row and up to 60 cm in inter-rows. Therefore, the greatest efficiency in nutritional management can be achieved by applying fertilizers within a radius of 50 cm around the plant.
12 July 2019 in Journal of Experimental Agriculture International
The present work aimed to characterize and evaluate Capsicum peppers in the South of the State of Espírito Santo, in order to estimate the variability among the accessions for the Germplasm Bank implementation. For this, 33 genotypes were collected through donations in four municipalities in the region. The genotypes were characterized based on nine quantitative descriptors: number of seeds per fruit (NS), number of fruit locules (NL), number of fruits per plant (NFR), plant height (PH), leaf width (LW), leaf length (LL), fruit length (FRL) and fruit diameter (FRD). Analysis of variance and means grouping by the Scott-Knott test was performed (P=.01). To estimate the diversity, the Tocher method was realized. The GT Biplot analysis was performed with using RStudio program to estimate discrimination, representativeness and correlation of characteristics. It was found a great diversity among the studied genotypes, being able to emphasize the accession Ifes 01 and Ifes 03 as the most divergent ones. The Tocher grouping allowed the formation of seven groups. The biplot analysis presented the formation of three groups of characteristics. The access Ifes 01 stood out for the group of characteristics FRL, NS and FRD. The Ifes 32 accession was highlighted for the PH and DC characteristics group, and the Ifes 20 accession was highlighted for the group formed by the NFR characteristic. It was observed that the characteristics that contributed the most to the divergence of accessions were PH and DC, and the most representative characteristic was DC. So, it’s concluded that there is great variability among the genotypes collected, presenting great phenotypic variation for the nine characters studied. In addition, some accesses were promising for plant breeding programs, pointing to gains in the various segments of the peppers market, which shows the importance of the collections of the producers in the South of Espírito Santo.
Studies on the genetic diversity of coffee trees are important, considering their role in the maximization of productivity and quality. However, the success of a breeding program depends on the existence of genetic variability in the population under study. Our study aimed to evaluate the genetic diversity of the morpho-agronomic and anatomical leaf traits of different cultivars of Coffea arabica grown in the Gorongosa mountain region, in the area of Gorongosa National Park, Mozambique. The experiment assessed nine coffee cultivars based on their morpho-agronomic and anatomical traits. The plagiotropic branch diameter, leaf dry mass, leaf mass per area, number of epidermal cells + stomata, and stomatal form indicated differences among the studied cultivars. Among the nine C. arabica cultivars grown in the mountainous region of Gorongosa National Park, Mozambique, low genetic variability in morpho-agronomic traits was detected, while the genetic variability in leaf anatomical traits was higher. The nine cultivars were segregated into two groups, one consisting of Catucaí Amarelo 2SL and Catuaí Vermelho IAC 81, and the second consisting of Catuaí Amarelo IAC 39, Catucaí Vermelho 19/8, Acauã, Catucaí 785-15, Costa Rica, Catimor 128, and Catuaí Vermelho IAC 44. The cultivar segregation into the two groups indicated that the morpho-anatomical traits can be considered during the selection stages in breeding programs.
The root system distribution of coffee, especially Coffea canephora cv. Robusta, remains poorly characterized. The aim of this study were: (i) to analyze the distribution of the root system in various genotypes of C. canephora cv. Robusta cultivated in the Amazon region; (ii) to evaluate genetic variability based on root traits; and (iii) to test the correlation between root traits, aboveground part, and production capacity. Roots were collected up to a depth of 60 cm and 30 cm away from the stems. The roots were washed, scanned, and processed to quantify root volume (mm3 cm−3), surface area (mm2 cm−3), diameter (mm), and length (mm cm−3). The variations in root systems reveled phenotypic variability among different genotypes of C. canephora cv. Robusta. Most roots were concentrated in the surface layer of the soil (0–30 cm), with LB015 standing out. At a depth of 50–60 cm, AS10, AS4, A106, and GJ08 had more roots than other genotypes, suggesting a promising capacity to avoid drought. There were significant negative correlations between root traits, aboveground part, and production capacity. This study provides valuable information for the selection of genotypes with desirable root traits for different environmental conditions, contributing to the improvement of management practices and breeding programs for Robusta coffee.