Multi-location Experiments Research Articles

Analysis of genetic variability for nutritional quality traits among maize inbreds adapted to Punjab: A North‐Western province of India

AbstractBackground and ObjectivesThe deficiency of essential amino acids such as methionine, lysine, and tryptophan in maize protein presents a significant challenge in meeting nutritional demand. Comprehensive evaluation of maize germplasm for variability of essential amino acids, protein content, starch content, and β‐carotene contents in grains, along with their relationships with yield and its associated traits, is a prerequisite for strengthening genetic enhancement for nutritional traits. Thus, the current study presents the profiling of 60 maize inbred lines across 11 nutritional quality and yield, aiming to identify variability in these traits and potential donor candidates for commercial breeding.FindingsThe test inbreds exhibited significant variations in the content of grain methionine (0.04%–0.28%), tryptophan (0.019%–0.069%), lysine (0.063%–0.318%), protein (9.31%–11.80%), starch (58.32%–70.88%), and β‐carotene (2.38 ppm–6.79 ppm). Additionally, variations were noted in grain yield (0.87–2.52 t ha−1). Inter‐relationship analyses suggested the feasibility of simultaneous selection of essential amino acids (methionine, tryptophan, lysine) and β‐carotene. The germplasm stock was clustered, and potential diverse donors identified were recommended for utilization in breeding programs. Furthermore, the use of Attenuated Total Reflectance‐Fourier Transform Infrared (ATR‐FTIR) spectroscopy for screening high methionine and high lysine lines in large germplasm based on differences in peak intensity at 2922 cm−1 and 1110 cm−1 was reported, respectively.ConclusionsThe multilocation experiment revealed genetic diversity in both nutritional quality and yield across the 60 inbreds. The absence of a negative correlation between the amino acids and β‐carotene indicates the possibility of the development of hybrids with elevated essential amino‐acid levels combined with high β‐carotene content.Significance and NoveltyThis is the first holistic report on the variability of nutritional quality traits coupled with yield in maize germplasm. Identified nutrient‐rich inbreds will serve as valuable germplasm in maize biofortification programs. AT‐FTIR is proposed as an easy screening technique and the first report, which can be employed for the initial screening of a large set of germplasm for methionine and lysine content.

Multi-environments Evaluation of Zn and Fe Enhanced Bread Wheat Genotypes in Optimum Areas of Ethiopia

A multi-location experiment was conducted during June, 2020–October, 2021 under rainfed condition at Kulumsa, Asasa, Adet, Holeta, and Sinana Research centers, Ethiopia to evaluate the genotype-by-environment interaction effect and grain yield stability of Zn and Fe enhanced bread wheat genotypes grown. The treatments constituted 21 advanced genotypes and two standard checks were evaluated in an alpha lattice design replicated three times and data analysis was carried using R software. The results showed that genotypes and genotype x environmental interaction had a significant (p<0.001) effect on days to 50% heading, days to 90% maturity, plant height, grain yield, and 1000 kernel weight. The bread wheat lines BW172862, EBW193416, BW172864, and EBW193414 were high-yielding across most test environments, whereas genotype EBW192455 and Hidasse were low-yielding ones. From stability analysis genotypes BW172862, and EBW193416 were identified to be the most adapted bread wheat genotypes. “BW172862 produced 24.43% and 86.38% yield advantage over the standard check (Lemu) and local check (Hidasse), respectively. The second candidate genotype EBW193416 also produced 23.58% and 85.1% yield advantage over the standard check (Lemu) and local check (Hidasse), respectively. EBW193416 and BW172862 have also exhibited lower Yellow and Stem rust severity compared to others across the test environments. Thus, BW172862 and EBW193416 were selected as best parent to recycle for bread wheat population improvement in 2023 for medium agro-ecology of Ethiopia.

Importance of mega-environments in evaluation and identification of climate resilient maize hybrids (Zea mays L.)

Multi-location experiments on maize were conducted from 2016 to 2019 at ten locations distributed across two agro-climatic zones (ACZ) i.e., ACZ-3 and ACZ-8 of Karnataka, India. Individual analysis of variance for each location-year combination showed significant differences among the hybrids; similarly, combined analysis showed a higher proportion of GE interaction variance than due to genotype. Mega-environments were identified using biplot approaches such as AMMI, GGE, and WAASB methodologies for the years 2016 to 2019. The BLUP method revealed a high correlation between grain yield and stability indices ranging from 0.67 to 1.0. Considering all three methods together, the three location pairs Arabhavi-Belavatagi, Bailhongal-Belavatagi, and Hagari-Sirguppa had three occurrences in the same mega-environment with a value of 0.67, and these location combinations consistently produced winning genotypes. Among the common winning genotypes identified, it was G7 during 2016 and 2017 and G10 during 2018 and 2019, based on WAASBY. The likelihood of Arabhavi-Nippani, Hagari-Mudhol, and Dharwad-Hagari occurring in the same mega-environment is minimal because they did not share the same winning genotype, with the exception of a small number of events. Despite being in the same agro-climatic zone, Arabhavi, Hagari, and Mudhol rarely had a winning genotype in common. An agro-climatic zone is grouped based on climatic and soil conditions which doesn’t consider GE interaction of cultivars thus, releasing the cultivars for commercial cultivation considering mega environments pattern would enhance the yield for the given target region.

Saffron spice quality in response to integrated nutrient management under lesser Himalayan conditions of Rawalakot Azad Jammu & Kashmir

Integrated nutrient management is an environment friendly approach of plant nutrition being used for crop productivity and improvement in soil quality on sustainable basis. A three-year multi-location experiment was conducted to estimate the spice quality of saffron subjected to the integration of organic and inorganic nitrogen sources. At each location, the experiment was laid out in randomized complete block design. The treatments were T1 = control (without organic/inorganic N source/amendment); T2 = Full recommended nitrogen (i.e. urea fertilizer @ equivalent to 100 kg N ha−1; UN100); T3 = Poultry manure (PM) @ equivalent to 100 kg total N ha−1 (i.e. PM100); T4 = Farm yard manure (FYM) @ equivalent to 100 kg total N ha−1 (i.e. FYM100); T5 = PM50+FYM50; T6 = UN75 + PM25; T7 = UN50 + PM50; T8 = UN25 + PM75; T9 = UN75 + FYM25; T10 = UN50 + FYM50; T11 = UN25 + FYM75 and T12 = UN50 + PM25+ FYM25. Among treatments, poultry manure (100%) and urea nitrogen with poultry manure (UN50 + PM50) significantly affected the quality attributes of saffron. On the other hand, among sites, the crocin, picrocrocin and saffranal contents were in order of Khaigala (23.81% crocin, 20.01% picrocrocin and 0.27% saffranal) >Trarkhel (19.04% crocin, 16.99% picrocrocin and 0.25% saffranal) and > Abbaspur (17.80% crocin, 15.45% picrocrocin and 0.23% saffranal). Similarly, among years, the crocin, picrocrocin and saffranal contents were significantly higher in the third year compared to the first and second year. In conclusion, the integration of organic nitrogen sources with inorganic nitrogen has the potential to improve saffron quality.

Genotype×Environment Interaction and Stability Analysis Using GGE Biplot for Grain Yield of Bread Wheat (Triticum aestivum) Genotypes under Low Moisture Stress Areas of Ethiopia

A multi-location Experiment was conducted using 28 genotypes and two checks during the main cropping seasons of 2017 and 2018 at Kulumsa, Dhera, Melkasa, Asasa, Ilala, and Geregera in moisture-stress areas of Ethiopia to evaluate the genotype-Environment interaction effect and grain yield stability of bread wheat genotypes. The experiment was arranged in alpha lattice design replicated three times. The stability analysis was carried out for grain yield using R software. ANOVA showed a highly significant difference among genotypes and genotype×environmental interaction for traits; days to heading, days to maturity, plant height, grain yield, 1000 kernel weight. The average mean yield of the genotypes across the environments was 4.5 with the range of 3.5–5.3 t ha-1. The genotypes ETBW 9578, ETBW 9565, ETBW 9570 and ETBW 9571 were top-yielding, ideal, and stable across the ten environments. However ETBW 9589 and Ogolcho were the low-yielding genotypes. The “which-won-where” graph categorizes the genotypes into four groups. The locations within the same group were closely correlated and share the same winning(vertex) genotype. E7 was ideal that has both discriminating abilities of the genotypes and representative of the other test environments. ETBW 9578 gave 37.7% and 39.1% yield advantage over the standard check Kingbird and local check Ogolcho, respectively. As a result the genotype ETBW 9578 was released in 2020 and designated by the variety name “Dursa”. Thus, it was concluded that the Dursa variety could be used as a stable variety for cultivation.

Productivity and Stability Evaluation of 12 Selected Avena magna ssp. domestica Lines Based on Multi-Location Experiments during Three Cropping Seasons in Morocco

Avena magna (2n = 4x = 28) is a tetraploid oat with a very high protein content compared to the hexaploid common oat, A. sativa (2n = 6x = 42). The wild type of A. magna originates from Morocco; its domestication has been achieved only within the past 25 years. The present study aimed to evaluate the productivity potential of an A. magna ssp. domestica collection of 11 advanced lines and a control variety, ‘Avery’. Twelve trials were conducted during three cropping seasons at four, three, and five locations and revealed significant differences among the accessions. Data on twelve agro-morphological characters and two disease traits were collected, and they confirmed the presence of variability in this oat germplasm set. Mean grain yield was 30.76 q/ha and varied from site to site, ranging from 6.89 q/ha at Bouchane_19 to 85.5 q/ha at Alnif_21. Across experimental sites, plant height ranged from 48.93 to 120.47 cm; thousand kernel weight from 32.83 to 49.73 g; and harvest index from 20.43 to 31.33%. Line AT6 was relatively tolerant of BYDV and crown rust infections, based on disease severity scoring at the heading stage. According to AMMI analysis, 78% of the grain yield variability was due to the environment factor and 4% was explained by the genetic factor. Among the highest-yielding lines, AT5 and ATC were relatively unstable. Line AT5 was more productive at the elevated site of El Kbab_19, and ATC performed better at the oasis location of Alnif_21 under irrigation. Line AT7 showed the most stable behavior; it was high yielding across the five environments and exceeded the general mean of the experiments. The A. magna ssp. domestica lines proved their suitability for cultivation under local farming conditions. Their nutritional quality, especially their high protein content, makes them good candidates for further testing in the Moroccan breeding program and for integration into local cropping systems.

Evaluation and Heritability Analysis of the Seed Vigor of Soybean Strains Tested in the Huanghuaihai Regional Test of China.

High seed vigor is a prerequisite for high and stable yield. At present, seed vigor is not considered a goal of soybean breeding in China. Therefore, the seed vigor status of soybean strains is unclear. In this study, the seed vigor of 131 soybean strains included in the Huanghuaihai regional test in 2019 was measured using the artificial accelerated aging method. Significant (p < 0.01) differences in seed vigor were found, with a coefficient of variation of four vigor indexes being more than 48%. The strains with high vigor only accounted for 28.24%, indicating the seed quality of the tested strains was generally not high. Furthermore, the seed vigor of four representative strains selected from each of three vigor types was evaluated using multiyear and multilocation experiments. The seed vigor indexes of high-vigor-type strains were the most stable, while medium- and low-vigor-type strains varied under different environmental conditions. The generalized heritability of the four vigor indexes of the three vigor types was more than 51% and in the order of high vigor type > low vigor type > medium vigor type. Our results suggested that the genotypes of high-vigor-type strains have a greater influence on seed vigor, so to ensure varieties with high seed vigor, this criterion should be prioritized in soybean breeding programs in China.

Effects of Fungicides and Cultivar Resistance on Fusarium Head Blight and Deoxynivalenol in Spring Barley from 2014 to 2019

Spring barley production and quality in the United States is severely impacted by Fusarium head blight (FHB), primarily caused by Fusarium graminearum. Management of FHB is best accomplished using an integrated approach including resistant varieties and fungicides. Field experiments were established from 2014 to 2019 to quantify the effects of host resistance, fungicide, and fungicide timing on management of FHB and deoxynivalenol (DON) and yield protection in spring barley. Three separate research objectives were investigated using multiyear and multilocation experiments. These included investigating the efficacy of prothioconazole + tebuconazole applied at either Feekes growth stage (FGS) 10.5 (full head) or 3 to 7 days after FGS 10.5; the efficacy of sequential fungicide applications occurring at both FGS 10.5 and 3 to 7 days after FGS 10.5 using prothioconazole + tebuconazole, metconazole, prothioconazole, or tebuconazole; and the efficacy and timing of pydiflumetofen + propiconazole. Pooled analysis results suggest that metconazole, prothioconazole + tebuconazole, and pydiflumetofen + propiconazole are all effective fungicides for reducing DON, reducing FHB, and protecting yield. The use of sequential fungicide applications with one occurring at FGS 10.5 and another at 3 to 7 days after FGS 10.5 provided greater suppression than a single application at FGS 10.5. The greatest DON reduction from pydiflumetofen + propiconazole occurred when applied at full head or 3 to 7 days after full head. Across all research objectives, the most effective single fungicide application timing to reduce FHB, reduce DON, and protect yield in barley is 3 to 7 days after FGS 10.5.

Limited yield penalties in an early transition to conservation agriculture in cotton-based cropping systems of Benin

Transitioning toward minimum or no tillage is challenging for smallholder farmers in sub-Saharan Africa (SSA), due to the possible yield penalties during the initial years of a transition. Understanding the early impacts of such transitions is crucial in a cash crop such as cotton, on which farmers rely for their income, and is necessary to inform agroecological strategies to cope with both these challenges. This study explores the combined impact of minimum or no tillage and fertilizer regimes on agronomic parameters of cotton–cereal rotations, as practiced by smallholder farmers in Benin. A multilocation experiment was set up in three different agroclimatic zones, namely, Savalou (7°55′41″, 1°58′32″), Okpara (2°48′15″, 7°72′07″), and Soaodou (10°28′33″, 1°98′33″). In each area, the experiment was laid out as a split-plot design with four replications (main plot = soil preparation; subplot = fertilizers regimes). The treatments consisted of three different forms of soil preparation, namely, tillage, strip tillage, and no tillage or direct seeding, and four fertilization regimes, namely, basal mineral fertilizers (BMF, 200 kg ha1 of N14P18K18S6B1 + 50 kg ha1 of urea), BMF + A (200 kg ha1 of calcium phosphate amendment, 22P2O5-43CaO−4S), BMF + C (400 kg ha1 of compost), and BMF + A + C. At all sites, direct seeding led to lower below-ground biomass growth and seed cotton yields compared with conventional tillage in an early transition to conservation agriculture starting from degraded soils (2% to 25%). Weak rooting under direct seeding resulted in lower cotton yields compared with that under tillage (−12%) and strip tillage (−15%). At 45 and 90 days after emergence, cotton plants were shorter under direct seeding compared with tillage (−9% and −13%, respectively) and strip tillage (−23% and −6%, respectively). Fertilizer regimes affected seed cotton yields differently across sites and treatments, with marginal responses within soil preparation methods, but they contributed to increase yield differences between conventional and no tillage. Considering the need for sustainable practices, in the context of degraded soils and poor productivity, such limited yield penalties under CA appear to be a reasonable trade-off in the first year of a transition. Alternatively, the results from the first year of this experiment, which is meant to continue for another 5 years, suggest that strip tillage could be a sensible way to initialize a transition, without initial yield penalties, toward more sustainable soil management.

Legume-rhizobium specificity effect on nodulation, biomass production and partitioning of faba bean (Vicia faba L.)

Greenhouse and multi-location experiments were conducted for two consecutive years to investigate the effects of rhizobium on nodulation, biomass production and partitioning of faba bean. Split-plot in randomized complete block design was used for field experiments. Treatments consisted of six rhizobium strains and three faba bean varieties. Peat carrier-based inoculant of each strain was applied at the rate of 10 g kg−1 seed. Non-inoculated plants without N fertilizer and with N fertilizer served as –N and + N controls, respectively. Data on nodulation, shoot dry weight and root dry weight were collected and analyzed. Inoculation of rhizobium significantly increased nodulation of faba bean under greenhouse and field conditions. Location x strain x variety interaction had significant effects on nodulation, dry matter production and partitioning. Rhizobium inoculation increased nodulation, shoot and root dry weights of faba bean across locations. For example, inoculation with rhizobium strains NSFBR-15 and NSFBR-12 to variety Moti resulted in 206.9 and 99.3% shoot dry weight increase at Abala Gase and Hankomolicha, respectively and 133.3 and 70.7% root dry weight increase on the same variety at the same sites, respectively. Nodulation and biomass production depend on the compatibility between faba bean genotype and rhizobium strain and its interaction with soil bio-physical conditions.

Fungicidal Management of False Smut Disease in Rice Caused by Ustilaginoidea virens

False smut of rice caused by the fungus Ustilaginoidea virens has been recorded, in recent years, in the all rice growing areas of State Uttar Pradesh, India. Recommended fungicides are not yet available for chemically controlling the disease. Therefore, uses of unregistered fungicides are common by the farmers, for the management of the disease. The present study, was undertaken to identify effectiveness of fungicides to control false smut of rice. Four systemic fungicides (Propiconazole 25% EC @ 1.0 ml/L, Azoxystrobin 18.2% + Difenconazole 11.4% SC @ 0.5 g + 0.5 ml/L, Azoxystrobin 18.2% @ 1.0 g/L and Tebuconazole 250 EC @ 1.0 ml/L) were evaluated as foliar application in the naturally induced diseased rice, at five different locations in district Siddharthnagar, Uttar Pradesh. Fungicide was applied twice, first at panicle initiation and second at early flowering stage. All the fungicides applied were found effective in controlling the disease. As compared to the untreated (only water application), the fungicide ‘Propiconazole 25% EC’ reduced the maximum disease severity by 93.57%, followed by ‘Azoxystrobin 18.2% + Difenconazole 11.4% SC @ 0.5 g + 0.5 ml/L’, Fungicide Tebuconazole 250 EC @ 1.0 ml/L was found least effective in controlling the disease. It is concluded that more multi-location experiments will be required to reach a decisive conclusion on foliar chemical options for controlling rice false smut disease in eastern parts of Uttar Pradesh.

Native Bradyrhizobium Strains From Ghana Can Enhance Grain Yields of Field-Grown Cowpea and Groundnut

The existence of large population of ineffective native rhizobia and inconsistent performance of exotic strains in Ghanaian soils necessitate the need to identify effective and locally adapted elite strains for enhanced legume-rhizobium symbiosis. This study was designed to test the suitability of two previously selected potential elite Bradyrhizobium strains for use as inoculants on cowpea (Vigna unguiculata L. Walp) and groundnut (Arachis hypogaea L.) in multi-location experiments. Field experiments were set up at 26 locations (12 planted with cowpea and 14 planted with groundnut) in the Northern region of Ghana. Four treatments were applied at each location: inoculation with Bradyrhizobium strains KNUST 1002 and KNUST 1006, a positive nitrogen (+N) control and a negative control (without nitrogen or inoculation) arranged in randomized complete blocks with four replications. The results showed that inoculation with strains KNUST 1002 and KNUST 1006 promoted significant increases in grain yields of both cowpea and groundnut. On average, inoculating cowpea with strains KNUST 1002 and KNUST 1006 resulted in 63 and 52% increases in grain yield when compared to the negative control. Pod yields of groundnut on the other hand, were significantly (p< 0.05) increased at 57% of the study location with one or both test strains. Responses to inoculation were, however, highly variable across the different study locations (i.e. significant Treatment ⸼ Location Interaction, TLI). A detailed analysis of this significant TLI based on the genotype main effect (G) plus genotype-by-environment (GE) interaction (GGE) biplot analysis revealed that location contributed 71 and 88% of the variation observed in cowpea and groundnut, respectively, and grouped the locations into mega-environments. These results demonstrate that native elite Bradyrhizobium strains KNUST 1002 and KNUST 1006 have potential for use as inoculants to increase cowpea and groundnut production in Northern Ghana.

Modeling the emergence of North African knapweed (Centaurea diluta), an increasingly troublesome weed in Spain

AbstractNorth African knapweed (Centaurea diluta Aiton) is an annual weed that is widespread in southern Spain and is of increasing concern in dryland cropping systems. Despite its expanding range in Spain, there is limited information on the emergence timing and pattern of this species, knowledge of which is critical for developing more timely and effective management strategies. Therefore, there is a need to develop simple and reliable models to predict the timing and emergence of this annual weed under dryland conditions. A multi-location field experiment was established across Spain in 2016 to 2017 to assess the emergence of C. diluta. At each of 11 locations, seeds were sown in the fall, and emergence was recorded. Overall emergence averaged 39% in the first year across all sites and 11% in the second year. In both years, the main emergence flush occurred at the beginning of the growing season. A three-parameter Weibull function best described seedling emergence of C. diluta. Emergence models were developed based on thermal time (TT) and hydrothermal time (HTT) and showed high predictability, as evidenced by root mean-square error prediction values of 10.8 and 10.7, respectively. Three cardinal points were established for TT and HHT at 0.5, 10, and 35 C for base, optimal, and ceiling temperatures, respectively, while base water potential was estimated at −0.5 MPa.

Dennis James Greenland. 13 June 1930—23 December 2012

Dennis Greenland was an outstanding soil scientist who combined the analytical rigour of a chemist with the practical application of an agricultural scientist. His early research employed X-ray diffraction and other emerging analytical techniques to determine the surface properties of clay minerals and their interactions with organic components of soils. This, in turn, led to research to understand the forces leading to aggregate and structural stability (and instability) in soils of the UK, Australia, Nigeria and the tropics generally. Simultaneously, Dennis engaged with the practical problems faced by farmers in the tropics to maintain the fertility of their soils and ensure long-term crop production; his early work (with Peter Nye) on shifting cultivation is regarded as a classic of the soil science literature. These two elements of his research came together during his periods as deputy director general, with responsibility for research, at the International Institute for Tropical Agriculture (IITA) in Nigeria (1974–1976) and the International Rice Research Institute (IRRI) in The Philippines (1979–1987). At both institutions he sought to improve the research in natural resources so that the genetic gains delivered by crop breeding could be achieved by farmers on their fields. At IRRI he encouraged research on rice-growing environments and improved water management taking account of catchment uses, and he promoted integrated approaches to nutrient management that combined organic and inorganic sources. This passion for integrated approaches to soil management led to his championing, and eventually chairing, the International Board for Soil Research and Management (IBSRAM), in which he played a major role in forming networks of multi-location experiments with many institutions.

Estimations of fibre trait stability and type of inheritance in cotton

Traits affecting fibre quality were evaluated in a multi-location environmental experiment. Four main cotton regions in Greece were selected as different environments. Five commercial cotton cultivars were used for evaluation of 10 fibre quality traits. Each cultivar was sown in 10 different fields in each region. Environmental fluctuations within regions affected each quality trait differently showing a different degree of inheritance. Four traits showed the lowest stability index values indicating quantitative inheritance, further four traits with intermediate values indicated determination by a few genes, while the more stable and thus with qualitative inheritance traits were considered to indicate fibre maturity and uniformity. The mean estimation of stability in multi-location experiments was found the same as in multi-genotype evaluation. Two cultivars (Elsa and Celia) were found to be more stable across the Greek environments and two regions favoured stability for almost all traits. Correlations between regions were high and the same was found between genotypes.

On-farm multi-location evaluation of occurrence of drought types and rice genotypes selected from controlled- water on-station experiments in Northeast Thailand

Rainfed lowland rice is the most common crop ecosystem in Northeast Thailand and varieties well adapted to drought-prone environments are required. On-farm multi-location experiments were conducted for 3 years to determine the drought type commonly developed, to identify genotype by environment interaction for rainfed lowland rice and to examine whether genotypic variation in these experiments was related to that in on-station controlled water- environment screening experiments conducted previously (Monkham et al., 2015). Among 32 on-farm experiments, 4 experienced continuous drought with no standing water during the whole growing season, and 3 of them all in high toposequence positions died before maturity. For the remaining experiments, both intermittent and terminal droughts were common, while some experiments developed early season drought and delayed transplanting but resulted in no apparent yield penalty. The first set of multi-location experiments consisted of 14 experiments in 6 provinces in Northeast Thailand across 2years with 24 common genotypes. Mean grain yield of 13 environments that were harvested was 2300–3900kgha−1 and no severe drought developed at any environment. While main effect of genotype was not significant for grain yield, genotype by environment interaction was significant, and the results of clustering analysis identified 3 environmental groups and 3 genotype groups that explained the main source of the genotype by environment interaction. The genotypic variation obtained in the on-farm multi-location experiments in one environmental group of low yielding environments was correlated with that obtained under earlier intermittent drought selection experiments on-station. The results also indicate the usefulness of screening genotypes based on short delays in the intermittent drought conditions on-station.A second set of multi-location experiments conducted throughout Northeast Thailand to test the performance of four genotypes selected from the first set of multi-location experiments confirmed that these genotypes outperformed the popular variety KDML105. The present study confirmed the usefulness of initial screening under intermittent drought conditions conducted on research stations followed by further on-farm selection. It is suggested that on-station selection experiments should target yield levels representative of on-farm yield levels.

Identification and multi-environment validation of resistance to rust (Uromyces viciae-fabae) in Vicia faba

A germplasm collection of 484 accessions of Vicia faba was screened for resistance to rust (Uromyces viciae-fabae) under field conditions. Accessions varied in the levels of rust infection, although no complete resistance was identified. Stability of resistance of the 39 most-resistant accessions was tested in a multi-location experiment in Austria, Egypt, Tunisia, United Kingdom and Spain over three additional field seasons. Genotype × environment interaction accounted for 43% of the sum of squares of the multi-environment evaluation, revealing instability of the phenotypic expression across environments. This might hamper the efficiency of selection suggesting the need for selection in different environments. Three possible mega-environments were discerned in the studied area, Mediterranean (Spain, Tunisia and Egypt), Oceanic (UK) and Continental (Austria). Córdoba (Spain) and Kafr El-Sheik (Egypt) showed as ideal environments for rust resistance screenings within Mediterranean environment. Several accessions (300, 303, 311, 313, 720, 1196 and 1271) were grouped as moderately to highly resistant in the three defined mega-environments. These accessions showed clear differences both in terms of reduced disease severity and high stability, which make them good candidates for international faba bean breeding programmes. Concerning each mega-environment, accessions 300 and 311 were the most resistant and stable ones across the Mediterranean one, followed by accessions 720, 1022, 1272, 1320 and BPL261. On the contrary other accessions (313, 452, 481 and 1196) were the most resistant in Oceanic and Continental environments. However, 452 and 481 were susceptible in the Mediterranean mega-environment. This contrasting performance across the environments was also supported by contradictory performance of the checks BPL261 and Baraca in Oceanic and Continental environments, suggesting differential virulence in rust populations, which deserves further attention.

Evaluation of spring barley breeding lines in a two-year multi-location experiment using some statistical methods

Abstract In breeding experiments conducted prior to tests connected with the registration of new breeding lines of crops, pre-preliminary and preliminary trials are carried out. In this study a comparison was made among some models of analysis of variance, in relation to the selection of new breeding lines of spring barley (Hordeum vulgare L.). The aim is to determine whether the choice of model of analysis of variance may influence the choice of tested breeding lines. The trait considered was the yield in two years of trials. A more comprehensive analysis of variance model was found to be superior. It was also found that the results of analyses performed using average measurements for lines significantly differ from those obtained on the basis of all measurements. It was concluded that the type of ANOVA model used may have an impact on inferences about breeding lines. Moreover, a lack of stability in the yields of tested lines was revealed, implying the necessity of several years of trials.

Spring Wheat Breeding: Evaluation of Selected Adapted Spring Wheat Germplasm in Eastern Canada

Twenty-five hard red spring wheat (&lt;em&gt;Triticum aestivum&lt;/em&gt;) lines, including three known cultivars used as checks, were grown in seven locations across Eastern Canada. The objective of this multi-location experiment was to evaluate selected Eastern Cereal and Oilseed Research Centre advanced lines (ECAD lines) from the Spring Wheat Breeding Program in order to identify the best lines for performance and grower trials. The lines from this trial performed very well compared to the check varieties, especially at the Ontario locations. Overall, the ECAD lines were on a par with or superior to the checks in terms of several attributes, including yield, protein content, and Fusarium head blight resistance.

GENOTYPIC STABILITY AND PHENOTYPIC ADAPTABILITY FOR SOME YIELD TRAITS IN SOME LONG STAPLE COTTON GENOTYPES

the development of genotypes, which can be adapted to a wide range of diversified environments, is the ultimate goal of plant breeders in a crop improvement program. A multilocation experiment was performed to study genotype by environment interaction (GEI) using different stability parameters. Twenty two genotypes obtained from the Egyptian cotton breeding programme, besides two check varieties were evaluated for seed cotton yield and lint yield stability under five locations in the Delta region of Egypt. The results showed that variances due to genotypes, environments and genotype x environment interaction were highly significant for both traits, which indicated that these genotypes interacted differentially with environments. The environmental variation caused more than 60% of the total variance on these genotypes, while the genotypes variations cause 3.96% and 4.341% for seed cotton yield and lint yield, respectively. Seven stability parameters were used to determine stability of these genotypes. The Genotypes; G6, G9, G18 G19, G20, G22 and G23 were the most stable genotypes across these different methods,( and some of them could be recommended for farthen use in the breeding programme). Also, these Genotypes showed high sustainability index ranged from 76% to 90% for both traits which indicate that these genotypes were stable across the environments and characterized with wide adaptability and highmean performance. The Spearman’s correlation coefficients between the two yield traits and seven stability parameters were insignificant except, with ecovalence (W2 i) model which was highly significant and positive. Within the parameters, most of them showed highly significant positive correlation with each other, indicating that these measures have similar aspects of stability.