AMMI and GGE Biplot Analysis for Stability of Yield in Mid-early Pigeonpea [Cajanus cajan (L.) Millspaugh] Genotypes

Background: The genotype × environment interaction greatly influences the success of breeding and in multi-location trials complicates the identification of superior genotypes for a single location, due to magnitude of genotype by location interaction are often greater than genotype by year interaction. This necessitates genotype evaluation in multi environments trials in the advanced stages of selection. Methods: Nine elite pigeonpea genotypes of mid-early duration were evaluated in six diverse locations in randomized complete block design with three replications during kharif, 2019 to ascertain the stable genotypes, environments discrimination and genotype by environment crossovers using AMMI and GGE biplot stability models. Result: The results in the present investigation revealed that first two principal components explained 73.4% of variation interaction, while, 80.50% in GGE biplot. Both the models identified WRGE-126 (G6) as stable performer with high yield (1733 kg ha-1) and among the locations Tandur (E1) measured as the ideal environment. Whereas, the environments, Adilabad (E3) and Warangal (E4) were observed representative with better discriminating ability.

Dissimilarity between Andropogon lateralis ecotypes under different defoliation frequencies and heights

ABSTRACT: Andropogon lateralis Nees is a native grass of southern Brazil and is one of the most frequent specie found in native grasslands. The species is widely distributed and has a high degree of phenotypic plasticity, which makes it highly adaptable to different edaphoclimatic conditions and management. This study aimed to evaluate the behavior of twelve ecotypes of A. lateralis, collected in different regions of the state of Rio Grande do Sul and cut to three different heights and subjected to two different defoliation frequencies. From September to February, the ecotypes were evaluated for total dry matter, leaf and stem yields. In addition, total, vegetative and reproductive tillers and plant height were measured. These characteristics are important for the selection of superior genotypes in terms of genetic variability and forage production. Total dry matter and leaf dry matter are characteristics with agronomic importance and they showed the highest correlation (r = 0.77), enabling an indirect selection for one of these characteristics. The natural selection of plants resulted in distinct structural, morphological and productive characteristics with heterogeneity that allows the selection and grouping according to the characteristics, ecotypes with superior agronomic characteristics can be included in breeding programs.

Sorghum cultivation of the ratoon system for increased yields in dry land

Planting sorghum twice a year on dry land is constrained by the short duration of rainfall, so it requires technology to increase yields with the ratoon cropping system. The research was carried out in Agricultural Technology Research and Assessment Installation of Bajeng, Gowa, South Sulawesi from March to October 2019. The superior genotypes of sorghum were planted on marginal land as the main crop with a spacing of 75 cm x 20 cm (66,666 plants/ha). The ratoon plant used a split-split plot design. The main plot consisted of two mulches: M1=no mulch + 50% dose of main crop fertilization and M2=sorghum stover mulch + biodecomposer 1kg/ha without NPK fertilizer. The sub-plots consisted of 2 populations: P1=population of 66,666 plants/ha (1 shoot/hole), P2=133,332 ratoon plants/ha (2 shoots per hole). The sub-sub-plots consisted of 5 (five) genotypes/varieties of sorghum: V1=Numbu, V2=No.58-1, V3=No. 86.1, V4=No.103-1 and V5=No. 113-1, so that 20 treatment combinations were obtained with 3 replications. The results showed that to obtain high grain yield in ratoon cultivation in dry land, NPK fertilization (150-100-50)/ha is still necessary. The increase in population density of ratoon from 66,666 to 133,333 plants/ha significantly affected the increase in grain yield. Sorghum genotype No. 58-1, No. 86-1, No. 103-1 and No. 113-1 is technically and economically feasible to be developed in the cultivation of the double harvest ratoon system with the profit (Rp 10,989,000-12,247,500/ha) from the cultivation of sorghum once the main crop (Rp 4,003,000-4,856,000). The R/C value is 2.00-2.10 and the MBCR value is 2.27-2.38.

Performance of Fenugreek (Trigonella foenum-graecum L.) Genotypes towards Growth, Yield and UPOV Properties

Background: Genetic diversity is referred to the diversity present within different genotypes of same species, serves as the most valuable reservoir in providing variability for various traits. This variability would provide a basis for improving the crop in breeding program. The present study aimed to assessment of genetic diversity and selection of superior genotypes for fenugreek breeding. Methods: In this study, 75 fenugreek genotypes with cultivars (Çiftçi and Gürarslan) were used and these genotypes were established in augmented trial design. Each genotype was analyzed for morphological and yield traits and nineteen traits were scored according to the International Union for the Protection of New Varieties of Plants (UPOV). Result: As a result of the study, PI 568215 and PI 577712 were noted as promising genotypes for seed yield and protein content, respectively. Dendrogram analysis showed that same origin genotypes were found in different main groups. Correlation analysis revealed that 22 positive or negative correlations were found among the examined properties. PCA analysis results were found among the examined properties and total variation was noted as 39.95%.

Screening coffee genotypes for Cercospora coffeicola resistance in Brazil

Several efforts have been made by many researchers worldwide to develop coffee plants resistant to different Cercospora species; however, studies concerning C. coffeicola , specifically, are still incipient. In the present study, a blend of strains from this pathogen was inoculated into 18 Brazilian commercial cultivars, a coffee clone of Arabica, as well as into 41 accessions from the Germplasm Collection of Minas Gerais, to evaluate the genetic resistance ability within the population and select superior genotypes for the breeding program. After predicting genotypic values of the evaluated material, the most efficient way to select genotypes based on the data of severity to brown eye spot (BES) was also examined. Moreover, the action of defense mechanisms against C. coffeicola attacks was investigated by assessing the levels of total soluble phenolic compounds and soluble lignin in contrasting genotypes regarding disease susceptibility. Based on the results, the accession MG 1207 Sumatra demonstrated an intrinsic genetic capacity to maintain low levels of severity to brown eye spot. This genotype can thus substantially contribute to the development of new cultivars, which may lead to reduced use of pesticides. This study also evidenced that four evaluations of severity is enough to reach accuracy and efficiency for the severity of BES, thus providing expressive genetic gains. Finally, it is suggested that the levels of lignin and phenolic compounds are not associated with the resistance of coffee genotypes to brown eye spot.

Biomass production and nutritional properties of promising genotypes of Tithonia diversifolia (Hemsl.) A. Gray under different environments

Tithonia diversifolia is a shrub with excellent forage characteristics that has shown a wide genetic and phenotypic diversity. The objective of this study was to determine the biomass production and nutritional quality of seven genotypes of T. diversifolia with outstanding characteristics for ruminant nutrition, to analyze the Genotype x Environment (GxE) interaction of biomass production and to compare the performance of these genotypes with grasses offered normally in tropical conditions. For the GxE interaction the AMMI and SREG models were used, and evaluations were made in three environments. In the GxE analysis, the interaction was significant and effects of the environment on biomass productivity were observed with differences between genotypes (p <0.05). In the three environments, the chemical composition was adequate to be offered to ruminants. It is worth noting the high content of crude protein (28.89 g/100 g of dry matter - DM), the low fiber content (30.95 g of neutral detergent fiber - NDF/100 g of DM) and the high percentages of in vitrodegradation of DM for all the genotypes. It is possible to conclude that there are superior genotypes of T. diversifolia with the ability to have good productive and adaptive performance for high-altitude and low-altitude zones with low fertility soils.

Incorporating Molecular Markers and Causal Structure among Traits Using a Smith-Hazel Index and Structural Equation Models

The goal in breeding programs is to choose candidates that produce offspring with the best phenotypes. In conventional selection, the best candidate is selected with high genotypic values (unobserved), in the assumption that this is related to the observed phenotypic values for several traits. Multi-trait selection indices are used to identify superior genotypes when a number of traits are to be considered simultaneously. Often, the causal relationship among the traits is well known. Structural equation models (SEM) have been used to describe the causal relationships among variables in many biological systems. We present a method for multi-trait genomic selection that incorporates causal relationships among traits by coupling SEM with a Smith–Hazel index that incorporates markers. The method was applied to field data from a Nebraska winter wheat breeding program. We found that the correlation and the relative efficiency increased for the proposed Smith–Hazel indices when the total causal information among traits was accounted for by the vector of weights (b), which includes the causal path coefficients in the causal matrix (Λ). On the other hand, when selection was based on a primary trait, for example yield, the proposed SI increased the mean yield of the best 28 (Top 10%) genotypes to 7%.

Morpho-agronomy performance, seed nutrition content, and Aphis craccivora resistance of cowpea (Vigna unguiculata) genotypes

Sas MGA, Wahyu Y, Syukur M, Hidayat P. 2021. Morpho-agronomy performance, seed nutrition content, and Aphis craccivora resistance of cowpea (Vigna unguiculata) genotypes. Biodiversitas 22: 4320-4326. Cowpea (Vigna unguiculata subsp. unguiculata) is an agricultural commodity that can be a source of vegetable protein and replace the need for soy as a food ingredient. The wide adaptability under sub-optimum conditions placed cowpeas as the choice to be developed. This study aimed to evaluate the cowpea genotype’s agronomic performance and resistance to Aphis craccivora to be proposed as superior genotypes. Observations were made on the morpho-agronomic characters, including the color of the young pods and dry seeds, the number of pods, the productivity of fresh pods and dried seeds, and the nutrition content. The resistance to Aphis craccivora was evaluated using a no-choice test whole plant for the resistance and tolerance evaluation. This study showed that the productivity of young pods (4.86-15.13 tons ha-1), dry seed productivity (0.83-2.71 tons ha-1). The protein content differed significantly among the 20 genotypes ranging from 19.24% to 24.45%. Aphid infestation significantly inhibited plant growth compared with non-infested plants. Infestation of Aphis craccivora decreased the dry weight of the plant by about 20% to 70%. Based on the aphid population, the 20 genotypes were classified into medium-high to very high aphid damage intensity.

Stability of Rice Mutant Lines By Linear Mixed Model And Suggestion A New Index Based For Yield Performance And Stability

Fourteen rice mutant lines with four cultivars were evaluated in a randomized complete block design with three replications in three locations in Iran (Rasht, ChaparSar and Fars province) during two growing seasons (2014-2016). In addition, a new index namely as equivalent index of stability and performance (EISP) is suggested for simultaneous evaluation of yield performance and stability. The heat map of yield performance and WAASB (weighted average of absolute scores based on BLUP (best linear unbiased prediction)) identified G3, G9, G6, G12 and G5 as highly productive and stable genotypes. Based on the analysis by multi-trait stability index (MTSI) G7, G5 and G1 were selected as superior genotypes. The top five superior genotypes based on harmonic mean and of the relative performance of genotypic values (HMRPGV) were G5, G12, G7, G2 and G1. For verification of EISP, its value was calculated for some of multi and univariate stability indices and identified genotypes G5 and G12 as the best ones. Principal component analysis indicated yield positively correlated with HMGV, RPGV, HMRPGV, EIS2P EIbP and EIPiP. In conclusion, G12, G5 and G9 had a significant advantage over all genotypes and could undergo selection or cultivar introduction processes.