Standard Cultivars Research Articles

Ecological implications of row width and cultivar selection on rice (Oryza sativa) and barnyardgrass (Echinochloa crus-galli)

Rice (Oryza sativa L.) producers in the Mid-south are experiencing difficulties with herbicide-resistant weeds such as barnyardgrass [Echinochloa crus-galli (L.) P. Beauv.]. As a result, methods that can alter E. crus-galli ecology are needed. This research evaluated the ecological implications of rice cultivar and row widths on crop and E. crus-galli growth. Overall, for E. crus-galli, as the row width increased, greater density, panicle counts, and seed production occurred. Echinochloa crus-galli density was 120% greater in a 38-cm row width than the 13-cm row width at the preflood rice stage. Reduced early-season rice canopy coverage in the wider row widths allowed for increased E. crus-galli densities. At the preharvest stage, E. crus-galli panicle counts were similar for the 13- and 19-cm rows. Row width did not affect rice yield, indicating wider row widths could be feasible agronomically, but additional weed management efforts would be needed because greater ecological advantages were obtained in narrower rows. Less E. crus-galli seed production occurred in competition with hybrid cultivars compared to inbred cultivars. Overall, the standard row width (19-cm) and hybrid cultivars would provide the greatest ecological advantage over E. crus-galli.

Selection of Standard Rice Cultivars for Evaluating Cracking Resistance and Finding a Novel QTL Responsible for It

Selection of Standard Rice Cultivars for Evaluating Cracking Resistance and Finding a Novel QTL Responsible for It

Morphological Characterization of Some Capia Pepper (Capsicum annuum L.) Genotypes

Capsicum annuum (Capia), a member of the Solanaceae family, has a rich genetic diversity in fruit and plant traits. To select Capia pepper genotypes with desirable morphological traits for the development of new hybrid capia pepper varieties, this study aimed to characterize genetic accessions generated from local populations, and standard and hybrid cultivars using morphological characters. One hundred and twelve genotypes were identified using 15 morphological traits (11 qualitative and 4 quantitative) and quantitative traits were measured while qualitative traits were observed. Cluster and Principal Component Analysis (PCA) was applied to determine the relationship between the lines identified as a result of single plant selection. As a result of the cluster analysis, a dendrogram was prepared to evaluate the morphological similarity between the lines, and nineteen groups were identified based on 15 variables. In Principal Component Analysis, six PC axes explained 66.2% of the total variation. As a result of the study, high morphological variability was observed among pepper lines. This evaluation of plant trait variability can assist geneticists and breeders in identifying populations with desirable characteristics for inclusion in pepper breeding programs.

Особенности высокорослого среднеспелого сорта сои Ягуар с признаком ускоренного прироста надземной биомассы

The tall, middle maturing soybean cultivar Jaguar with a trait of accelerated formation of aboveground biomass was obtained as a result of individual selection in F4 from the hybrid combination Vilana × D-7/10 by tall growth (> 150 cm) of the stem, large seeds, middle maturity and lodging resistance. Based on the results of variety testing in 2020–2023, the soybean cultivar Jaguar exceeded the standard cultivar Vilana by 0.26 t/ha of yield. With an average vegetative period of 123 days at the latitude of Krasnodar (45°), the height of plants of this cultivar is 138 cm, varying over the years from 120 to 154 cm. In optimal moisture conditions, the weight of 1000 seeds is 160–190 g. The phenomenon of accelerated formation of aboveground biomass of plants of the cultivar Jaguar y in optimal cultivation conditions is confirmed by a 44% more intense daily increase in plant height and a 55% more intense daily increase in aboveground biomass compared to these indicators for the standard cultivar Vilana. The new tall, middle maturing soybean variety Jaguar, with a trait of accelerated formation of aboveground biomass, is characterized by increased responsiveness to additional moisture by increasing the plant height to ultra-high, increasing the number of nodes, beans and seeds, seed size and weight, and yield. It has increased resistance of tall plants to tilting and lodging due to excessive moisture due to the increased mechanical strength of the stem. Due to its tall growth and high positive response to additional moisture supply, it is suitable for cultivation in the southern foothill and central zones of the Krasnodar region, with irrigation throughout the North Caucasus and Lower Volga regions of the Russian Federation, as well as in the republics of Central Asia and Transcaucasia.

Повышение эффективности селекции сои с пониженной реакцией на длину дня на примере сорта Липчанка

A very early maturing soybean cultivar Lipchanka with a reduced response on a day length was isolated from the hybrid combination F4 D-12/14 × L-247 by traits of productivity, cold resistance, photoperiodic sensitivity, and the morphotype of the flower ovary style. The Lipchanka variety belongs to a very early maturity group, at the latitude of Krasnodar (45°) it ripens in 95 days, and in terms of yield exceeds the standard cultivar Barguzin by an average of 0.11 t/ha. In a competitive variety testing in Krasnodar in 2021–2023 its yield was 1.32–3.19 t/ha. In a competitive variety trial in Lipetsk at a latitude of 52°, the duration of the growing season of this cultivar averaged 105 days with a yield of 2.41–2.67 t/ha, which exceeded the standard variety Barguzin by 0.09 t/ha. Under the conditions of the Kaluga region, at a latitude of 54°, the cultivar Lipchanka had a growing season of 113 days and successfully ripened until mid-September. The height of Lipchanka plants at the latitude of Krasnodar was 70–85 cm. In the Lipetsk region, the plant height of Lipchanka varied within 70–95 cm. In the conditions of the Kaluga region, the height of the cultivar Lipchanka was 71 cm. The new very early maturing soybean cultivar Lipchanka has reduced sensitivity to the range of day lengths formed at latitudes of 45–54°, high yield in the long-day conditions of the Central Black Earth region, and successful ripening in the conditions of the Central region of the Russian Federation. Such features of the cultivar allows to recommend it for cultivation in the Central, Volga-Vyatka, Central Black Earth, North Caucasus, Middle Volga, Lower Volga, Ural, and West Siberian regions of the Russian Federation.

Morphological characterization and molecular marker-assisted selection for resistance to Tobacco mosaic virus (TMV) and Tomato spotted wilt virus (TSWV) in S2 population of capia pepper (Capsicum annuum L.)

Morphological characterization and molecular marker-assisted selection for resistance to Tobacco mosaic virus (TMV) and Tomato spotted wilt virus (TSWV) in S2 population of capia pepper (Capsicum annuum L.)

Morphological, chemical, and molecular characterization of a new late-leafing and high fruit quality hazelnut (Corylus avellana L.) genotype

AbstractHazelnuts are widely employed in various dietary practices, making them one of the most frequently utilized nuts. This study morphologically, chemically, and molecularly characterized a new hazelnut genotype throughout the 2018 to 2020 growing seasons. The variety burst leaf buds between 10th and 15th April and reached harvest maturity between 5th and 15th September. The genotype bore a mean of 2.33 nuts per cluster, with the majority of clusters consisting of double and triple nuts. The means of the nut weight was 2.38 g, the kernel weight was 1.35 g, the kernel ratio was 56.81%, the shell thickness was 0.96 mm, the nut size was 18.32 mm, the kernel size was 14.77 mm, the good kernel ratio was 91.7%, the protein content was 13.5%, the oil content was 55.8%, the oleic acid ratio was 81.43%, and the linoleic acid ratio was 10.68%. The genetic similarity rate between the new hazelnut genotype and the standard Çakıldak, Palaz, Tombul cultivars, as well as randomly selected Çakıldak hazelnut clones from the region, ranged from 0.58 to 0.98. Additionally, the polymorphism rate varied from 45.5 to 100%. On average, the investigated hazelnut genotype exhibited a genetic distinctiveness of 38% compared to randomly selected Çakıldak clones from the same region, and 47% compared to standard hazelnut cultivars. Consequently, this genotype could serve as valuable genetic material for hazelnut breeding programs through genetic distinctiveness and promising nut quality, and could potentially be registered as a new cultivar.

Characterization of genetic diversity of greens‐type hybrid bermudagrass selections through SSR markers and morphological analysis

AbstractThe development of Tifgreen bermudagrass, and the subsequent mutations of this cultivar, has revolutionized the game of golf in the southern United States as superintendents have access to high‐quality putting surface capable of withstanding hot summers. However, the lack of genetic diversity may make them vulnerable to various pests and the low tolerance to freeze temperatures may make them susceptible to winterkill. In recent years, Oklahoma State University and other universities have begun to create new interspecific F1 hybrids between common (Cynodon dactylon) and African bermudagrasses (C. transvaalensis) for putting greens. The objectives of this study were to investigate the genetic diversity and variation among 14 experimental genotypes and two standard cultivars (TifEagle and Tifdwarf). Simple sequence repeat (SSR) markers and morphological characteristics were used to evaluate the genetic relationships and variation among the 16 genotypes. Results showed significant variation for 11 vegetative traits and two reproductive traits. The phenotypic coefficient of variation was greatest for the third internode length and the least for the first leaf angle for both the field and greenhouse trials. The morphological cluster analysis also showed variation between the two trial environments. The SSR marker cluster analysis showed the 16 genotypes were grouped into four major groups, with a similarity coefficient ranging from 0.44 to 1. The highest similarity was found among the two commercial standards and an experimental ultradwarf from Florida. Several new genotypes (OKC3920, 5 × 23, 11 × 2, 19 × 19, and 34 × 20) were also grouped with the ultradwarf genotypes in the morphological cluster analysis, showing the possibility of achieving similar morphological traits with new genetics. Further field evaluations are needed to determine the performance of these genotypes under low mowing heights.

Cloning and functional mechanism of the dwarf gene gba affecting stem elongation and cellulose biosynthesis in jute (Corchorus olitorius).

Plant height (PH) is an important factor affecting bast fiber yield in jute. Here, we report the mechanism of dwarfism in the 'Guangbaai' (gba) of jute. The mutant gba had shorter internode length and cell length compared to the standard cultivar 'TaiZi 4' (TZ4). Exogenous GA3 treatment indicated that gba is a GA-insensitive dwarf mutant. Quantitative trait locus (QTL) analysis of three PH-related traits via a high-density genetic linkage map according to re-seq showed that a total of 25 QTLs were identified, including 13 QTLs for PH, with phenotypic variation explained ranging from 2.42 to 74.16%. Notably, the functional mechanism of the candidate gene CoGID1a, the gibberellic acid receptor, of the major locus qPHIL5 was evaluated by transgenic analysis and virus-induced gene silencing. A dwarf phenotype-related single nucleotide mutation in CoGID1a was identified in gba, which was also unique to the dwarf phenotype of gba among 57 cultivars. Cogid1a was unable to interact with the growth-repressor DELLA even in the presence of highly accumulated gibberellins in gba. Differentially expressed genes between transcriptomes of gba and TZ4 after GA3 treatment indicated up-regulation of genes involved in gibberellin and cellulose synthesis in gba. Interestingly, it was found that up-regulation of CoMYB46, a key transcription factor in the secondary cell wall, by the highly accumulated gibberellins in gba promoted the expression of cellulose synthase genes CoCesA4 and CoCesA7. These findings provide valuable insights into fiber development affected by endogenous gibberellin accumulation in plants.

Ekmeklik Buğday (Triticum aestivum L.) Çeşitlerinde Yağışlı Koşullarda Verim ve Kalite Parametrelerine Genotip Çevre Etkisi ve Stabilite

The significant genotype by environment interaction is a major matter for wheat breeding research. The study was carried out for seven growing season (between 2010-2011 and 2016-2017) in the Edirne location in the Trakya region, Türkiye. Each year was considered as a single environment. In the study, a regional yield trial of 25 genotypes, 5 of which were standard cultivars were evaluated across seven environments. The experiments were arranged in a randomized complete block design (RCBD) with four replications. The characters such as yield, days to heading, plant height, thousand kernel weight, hectoliter weight, protein ratio, wet gluten content, gluten index, grain hardness and sedimentation value were investigated in the study. The result of the variance analysis (ANOVA) demonstrated considerable differences (p

Quality Assessment and Evaluation of Amino Acid Profile of Black Wheat Supplemented Noodles

Background: Functional foods are a topic of ongoing industrial use and research. Currently, coloured grain is being prioritized more in research since it is a source of neutraceutical chemicals. Black colored wheat is known for its anthocyanin content. Black wheat therefore has the potential to offer extra health advantages over those that standard wheat cultivars typically offer. Noodles are most popular products widely consumed throughout the world and represents second in global consumption to bread. The present study was undertaken to evaluate effect of processing on loss of amino acids content in black wheat supplemented noodles and control white noodles. Methods: In the present study, High performance liquid chromatography was used for the quantification of amino acids in Black and Netravati white colored wheat flour and prepared black wheat supplemented noodles and control white noodles samples prepared by extrusion. Result: Black wheat flour and Black wheat supplemented noodles samples had higher total amino acid content, Essential amino acid content and per cent essential amino acid score in comparison Netravati white flour and control noodles samples prepared from whole Netravati white wheat flour, while content of lysine was more in Netravati white wheat flour and control noodles samples. The noodles samples prepared exhibited average percent reduction in amino acid content in black and Netravati white wheat were 1.06 and 2.63%, respectively. Black wheat flour and black wheat supplemented noodles were rich in anthocyanins also rich in amino acids in comparison to Netravati white wheat flour. Minimum losses in amino acid content were observed in Black wheat supplemented noodles, while maximum losses were observed in Netravati white wheat control noodles samples.

Selena – a new cotton variety

The aim of this research was to study the productive potential and evaluate the fiber properties of the new Selena cotton variety. The variety was studied in competition variety trials conducted in 2017-2022 in the experimental field of the Field Crops Institute in the town of Chirpan. In the IASAS system the variety was tested in 2021-2022. It was approved as a new cotton variety in 2023. Selena variety was created by remote hybridization from the crossing of the allotetraploid Gossypium thurberi Tod. × Gossypium raimondii Ulbr. with Dorina variety and subsequent backcrossing with Darmi variety. Selena variety is an early and productive new cotton variety with improved fiber quality. The vegetation period was 106-111 days. In seed cotton yield of 1663 kg/ha, on average for 6 years, it surpassed the standard cultivar Chirpan-539 by 12.3%. According to the IASAS data, in seed cotton yield of 2163 kg/ha it exceeded the two standard cultivars, Chirpan-539 - by 2.2%, Avangard-264 - by 1.3%, the average standard (average of the two standards) - by 1.8%. In lint yield of 95.5 kg/ha Selena variety was equal to Avangard-264, surpassed Chirpan-539 by 2.9% and respectively the average standard - by 1.4%. Selena variety had a number of valuable technological fiber qualities and in some indicators surpassed both standard cultivars. Compared to the two standard cultivars it had better Spinning Consistency Index (SCI), greater Upper Half Mean Length and fiber strength, lower micronaire, better spectroscopy with RD difference reflection than Chirpan-539, less yellowness than Avangard-264 and better fiber whiteness. Selena variety combines better productivity with better technological fiber qualities than the standard cultivars, which defines it as a new achievement in the selection of cotton in our country.

Phenotypic Variability for Leaf and Pod Color within the Snap Bean Association Panel

The color of vegetables is an important factor in consumer food choices and in cultivar choice by growers and processors for production. In absorbing a broad spectrum of light, leaves support plant development by influencing factors such as biomass accumulation, chlorophyll content, and reproductive growth. The edible organ of the snap bean (Phaseolus vulgaris L.) is the pod, and its color is not only one of the most important traits for commercial consideration, but also influences phytonutrient content. Although chlorophyll provides the base color, other compounds such as carotenoids and flavonoids may affect leaf and pod color. Darker yellow- or blue-green pods are preferred for processing, but there is more leeway for fresh market, with lighter-colored pods being acceptable. This research characterized leaf and pod color variation in the 378-member Snap Bean Association Panel. Leaf and pod colors were measured with a colorimeter using the L*a*b* scale, which was then transformed to L* (lightness), C* (chroma), and H° (hue angle) for analysis. Both green and wax bean accessions had predominantly green leaves, even though both exterior and interior colors of pods varied by accession. The leaves at the upper level in the canopy were lighter than lower and middle-level leaves. C* of leaves was similar across environments but leaves from the field were greener than leaves of greenhouse-grown plants when converted to Royal Horticultural Society (RHS) values, even though they had similar H°. L* did not differ for corresponding leaf positions of both field and greenhouse leaves. Purple pods were darker (lowest L*) and yellow pods were lighter (highest L*). Although wax beans had similar exterior and interior colors, accessions with purple exterior of pods had green interiors. Green pods were generally two times higher for L* and lower in C* compared with leaves. Pod interior L* was darker than exterior in both years. Pod exterior L* was not significantly different among accessions, whereas pod interior L* differed significantly between years. Broad sense heritabilities ranged from 0.69 to 0.88 for L*, 0.12 to 0. 87 for C*, and 0.81 to 0.89 for H°. Although greater variation was observed in pods than leaves, lower heritability was determined. Moderate correlations between leaf L* and the interior and exterior pod L* implies that it would be possible to select for pod color on the basis of leaf color, with verification using standard cultivars.

Investigation of management practices to optimize cereal rye cover crop-based weed mitigation in Canadian sweet corn production

Abstract Fall-sown cereal rye has gained popularity as a cover crop in vegetable production due to its weed-suppressive capabilities. However, previous research has shown that replacing preemergence and/or postemergence herbicide applications with roller-crimped rye has variable success at controlling weeds and maintaining vegetable cash crop yields. The objective of this research was to determine whether roller-crimped rye can provide season-long weed control and maintain sweet corn yield. Two rye cultivars (early vs. standard maturity) were compared at three seeding rates (150, 300, and 600 seeds m−2) for their effect on weed control and sweet corn yield. The trial was conducted at three locations: Harrow, ON, and St. Jean-sur-Richelieu, QC, from 2019 to 2021; and Agassiz, BC, in 2019 and 2021. Results suggest that although the early-maturing cultivar allowed for earlier roller crimping in some locations, it was inferior at weed control and resulted in lower sweet corn yield than local standard cultivars. The average rye biomass was lower than the current literature recommendations, and the resulting level of weed control was not high enough to prevent sweet corn yield loss in cover crop treatments. Weed control provided by roller-crimped rye peaked between crimping and 8 wk after crimping and was highest in the standard cultivars sown at 300 and 600 seeds m−2. Preliminary testing of supplemental postemergence weed control showed evidence for sweet corn yields comparable to the weed-free no-cover crop check. However, more research is needed. Overall, with the cultivars and seeding rates tested, roller-crimped rye is not a suitable stand-alone weed control option in sweet corn production. Given the benefits of cover crops, further research should evaluate its potential as a component of an integrated weed management program.

Устойчивый к полеганию, крупносемянный сорт сои Рысь

Resistant to lodging, large-seeded mid-early maturing soybean cultivar Rys’ was obtained as a result of individual selection in F4 from the hybrid combination Slavia × Shama SRP on differentiating back-grounds based on the characteristics of semi-determinant stem growth, large seeds, reduced response to day length, cold and frost resistance. Based on the results of variety testing 2019–2022, the soybean cultivar Rys’ exceeded the standard cultivar Vilana by 0.54 t/ha by yield. The height of plants at the latitude of Krasnodar (45°) is 90–109 cm. In optimal moisture conditions, the weight of 1000 seeds of this cultivar is 165–207 g. The new high-yielding soybean cultivar Rys’ is highly resistant to low air and soil temperatures, and also reacts poorly to nonoptimal day lengths. This allows it to be cultivated in soybean-producing farms in the North Caucasus and Lower Volga regions of the Russian Federation, as well as in the republics of Central Asia and Transcaucasia at latitudes from 40 to 50°.

Очень высокорослый среднеспелый сорт сои Мамонт

A very tall, middle maturing soybean cultivar Mamont, with traits of gigantism, was obtained as a result of individual selection in F4 from the hybrid combination Vilana × Pin GD for the characteristics of tall growth (> 160 cm) of the stem, large seeds, mid-ripening and non-lodging ability. Based on the results of variety testing 2020–2022, the soybean cultivar Mamont exceeded the standard cultivar Vilana by 0.18 t/ha by yield. The height of plants at the latitude of Krasnodar (45°) is 152–174 cm. In optimal cultivation conditions for moisture supply, the weight of 1000 seeds of this cultivar is 165–195 g. The phenomenon of the gigantism in plants of the Mamont cultivar in optimal growing conditions is confirmed to be 48 % more intense daily increase in plant height, and a 71% more intense daily increase in aboveground biomass compared to these indicators for the standard cultivar Vilana. The new very tall middle maturing soybean cultivar Mamont, with traits of gigantism, is distinguished by increased responsiveness to additional moisture by increasing the traits of plant height to ultra-high, increasing the number of nodes, beans and seeds, seed size and weight, and yield. It has increased resistance of tall plants to tilting and lodging due to excessive moisture due to the increased mechanical strength of the stem. Due to its tall growth and high positive response to additional moisture supply, it is suitable for cultivation in the southern foothill and central zones of the Krasnodar region and on irrigated plot throughout the North Caucasus and Lower Volga regions of the Russian Federation.

In Vitro Screening of Molecular Diversity Among Sorghums (Sorghum bicolor (L.) Landraces in Marathwada Region by Molecular Markers.

Allelic variation is a valuable tool for displaying high levels of polymorphism within species and is closely correlated with crop productivity. In Marathawada, there is a significant amount of phenotypic heterogeneity among sorghum landraces. However, molecular variability needs to be reevaluated in order to identify any potential barriers that can interfere with current improvement initiatives. In the current work, we used 5 SSR markers to categorize 20 genotypes of elite (Sorghum bicolor L. Moench) accession from the Marathwada region, including one standard cultivar from various agro-economic zones. According to the results of this study, 14 alleles were found among the 20 genotypes, with a PIC value that ranged from 0.37 to 0.70 and a mean of 0.44 per locus. Each locus had anything from 1 (gpsb089) and 5 (mSbCIR223), with an average of 2.80 alleles per locus. A neighbor-joining tree was constructed and showed clustering of genotypes into two groups; this indicates that there is considerable diversity in genotypes compared with advanced cultivar for desired genotype (IS1042) by using SSR markers. Results show that most diverse cultivars were IS-4564, IS18357, and IS-18381, and significant variation was also reported in IS4566 and IS18379.

Prebreeding studies of leaf rust resistant Triticum aestivum/T. timopheevii line L624.

Triticum timopheevii Zhuk. attracts the attention of bread wheat breeders with its high immunity to the leaf rust pathogen. However, introgressions from this species in Triticum aestivum L. are little used in practical breeding. In the presented study, the agronomic value of T. aestivum/T. timopheevii line L624 was studied in comparison with the parent cultivars Saratovskaya 68, Dobrynya and the standard cultivar Favorit during 2017-2022. Introgressions from T. timopheevii in L624 were detected by the FISH method with probes pSc119.2, pAs1 and Spelt1, as well as microsatellite markers Xgwm312, Xgpw4480 and Xksum73. Translocations of 2AS.2AL-2AtL and on 2DL were detected as well. Line L624 is highly resistant to Puccinia triticina both under the background of natural epiphytotics and under laboratory conditions. PCR analysis with the DNA marker of the LrTt1 gene (Xgwm312) revealed that it is not identical to the Lr gene(s) in L624. According to a five-year study, the grain yield of L624 was, on average, higher than that of Favorit and Dobrynya, but lower than that of Saratovskaya 68. Line L624 had a lower weight of 1000 grains than the recipients, and was at the same level with the standard cultivar Favorit. Introgressions from T. timopheevii in L624 increased the grain protein content by comparison with Saratovskaya 68 and Favorit, but it was at the same level as in Dobrynya. As for parameters of flour and bread, L624 was not inferior to the recipient cultivars, but by volume and porosity of bread, it surpassed Saratovskaya 68. Moreover, L624 surpassed Favorit by the elasticity of the dough, the ratio of the elasticity of the dough to the extensibility and the strength of the flour. Thus, the results obtained suggest that introgressions in chromosomes 2A and 2D in L624 do not impair baking properties.

Determination of the tolerance of physiological, morphological, and yield parameters of landrace durum wheat (Triticum durum Desf.) to high-temperature stress

In the South-eastern Anatolia Region, where the climate is favorable to cultivation for durum wheat, there have been notable reductions in both yield and quality due to biotic and abiotic stress factors in the region. Primary one of these stresses is high-temperature stress. High-temperature stress, specifically during the late flowering stage and early grain filling stage, results in substantial reductions in both crop yield and quality. In this study, several practical, easily and rapidly quantifiable physiological, morphological, and yield-related parameters that may be used in durum wheat improvement programs in the region for high-temperature stress tolerance were investigated. Ninety landrace durum genotypes and 4 standard cultivars were used. The study was carried out at GAP (South-eastern Anatolia Project) International Agricultural Research and Training Centre in an air conditioning room according to an augmented design under optimum conditions and stressful conditions where high-temperature stress was created. Compared to optimum conditions, there were reductions in flag leaf greening time by 20%, days to maturity by 7%, spike length by 10%, peduncle length by 18%, grain filling time by 23%, number of spikelets on the spike by 12%, number of grains on the spike by 39%, and thousand-kernel weight by 33%, while grain filling rate increased under high-temperature stress conditions. The genotypes 82, 83, 87, 88, 99, and 103 and the standard varieties Artuklu and Sümerli prevailed in both optimum and stress conditions. The fact that leaf erectness, flag leaf greening time, grain filling time, and leaf chlorophyll content among morphological and physiological characteristics had a significant correlation with yield components under both conditions indicates that these characteristics can be used as selection criteria for tolerance to stressful conditions in the region.

Ordu ekolojisinde farklı klonal anaçlar üzerinde yetiştirilen elma çeşitlerinin fenolojik, morfolojik ve verim özellikleri

This study was carried out to determine the phenological, morphological traits and yield values of some standard apple cultivars grafted on M9 and MM106 clonal rootstocks in Ordu (Türkiye) ecological conditions. In this context, in regional conditions, blooming periods, harvest dates, rootstock and trunk development, yield and yield efficiency values of rootstock/cultivar combinations were examined. According to the research findings, the earliest first bloom (14/11 April) and full bloom (18/17 April) were observed in the Granny Smith/M9 combination, while the earliest harvest was realized in Mondial Gala/M9 (11 September, 29 August) and Galaxy Gala/MM106 (29 August) combinations. Also, the yield was determined between 2.49 kg tree-1 (Fuji/MM106)-8.95 kg tree-1 (Mondial Gala/M9), and yield efficiency was determined between 0.14 kg cm-2 (Fuji/MM106)-1.16 kg cm-2 (Mondial Gala/M9). In the principal component analysis results, the first component was associated with crown width, canopy volume, shoot diameter, yield, yield efficiency, and shoot length and explained 48.3% of the total variation. The second component explained 33.1% of the total variation of the obtained data and was determined to be related to crown height, rootstock diameter, and trunk diameter. As a result, it was concluded that the morphological development and phenological stages of the examined rootstock/cultivar combinations were generally suitable for the ecological conditions of Ordu province. Key Words: Blooming, Canopy volume, Malus domestica,