Culm Length Research Articles

Screening Direct Seeding-Related Traits by Using an Improved Mesocotyl Elongation Assay and Association between Seedling and Maturity Traits in Rice

Direct seeding (DS) of rice gained much attention due to labor scarcity and unavailability of water. However, reduced emergence and poor seedling establishment are the main problems of DS which causes significant yield losses. Herein, DS-associated seedling traits of three major rice groups, i.e., Indica (Ind), Japonica (Jap), and aus-type (Aus), were evaluated by using an improved mesocotyl elongation assay. The associations among different traits at the seedling and maturity stage were also studied. Significant variation was observed among the cultivars of different rice groups. The Aus group cultivars showed higher mean values for coleoptile (C, 3.85 cm), mesocotyl (MC, 4.17 cm), shoot length (SL, 13.64 cm), panicle length (PL, 23.44 cm), tillers number (T, 15.95), culm length (CL, 105.29 cm), and plant height (PH, 128.73 cm), while the Indica and Japonica groups showed higher mean values of grain length (GL, 8.69 mm), grain length/width ratio (GL/WR, 3.07), and grain width (GW, 3.31 mm), with 1000 grain weight (TGWt, 25.53 g), respectively. Pairwise correlation analysis showed that MC, C, and SL were positively correlated among themselves and with PL, CL, and PH. Moreover, based on principal component analysis (PCA), C, MC, SL, CL, and PH were identified as the major discriminative factors in the rice cultivars. This study describes the development of desired DS rice variety with long MC and semidwarf in height and suggests that Aus group cultivars can be used as the donor parents of favorable DS-associated traits in rice breeding programs.

Performance of Doubled Haploid Elite Rice (Oryza sativa L.) Germplasm for Grain Yield and Associated Traits in Harare, Zimbabwe

A field experiment was conducted in 2018/2019 growing season at the Scientific Industrial Research and Development Center under irrigated conditions using the simple alpha lattice (7 ∗ 7) design, with three replications. The objective of the study was to determine the performance of 44 elite rice lines that were selected and shared from elite doubled haploid germplasm and five cultivars were used as checks. All evaluated genotypes exhibited significant variation in the traits measured except for number of grains/panicle, total tillers/plant, and effective tillers/plant. Elite line 70462 was found to be the highest yielding, with yield advantage of 66% over the high yielding local check (Nerica 7). High values for broad sense heritability were recorded for days to 50% heading, panicle length, culm length, number of filled grains/panicle, 1000-grain weight, grain length, grain shape, and grain yield and indicated lesser influence of environment in expression of these traits, hence amenable to simple selection. Correlation analysis revealed that grain yield manifested significantly positive correlation with filled grains/panicle contributing the highest correlation (r = 0.784), followed by culm length (r = 0.605), spikelet fertility/panicle (r = 0.677), grain length (r = 0.551), 1000-grain weight (r = 0.518), panicle length (r = 0.449), and number of grains/panicle (r = 0.328). Based on grain yield, number of filled grains/panicle and spikelet fertility/panicle, panicle length, and earliness, lines 70462, 60143, 70383, Arica 3, Sahel 177, 6040, 70537, 60409, and 70476 had the best performance. Selection of these traits would be more effective for yield improvement in rice and these promising lines could be used in the varietal development and can be tested in multilocational trials and on-farm trials in Zimbabwe with the possibility of release and commercialization.

EVALUATION OF GENETIC DIVERSITY OF THE BLACK GLUTINOUS RICE BASED ON AGRO-MORPHOLOGICAL CHARACTERS

The study assessed the variations in nine agro-morphological characters among and within the black glutinous rice (Oryza sativa) population from Chau Thanh District, Tra Vinh Province. The nine quantitative agromorphological characters that were measured include culm length, leaf length, leaf width, number of panicles, panicle length, grain length, grain width, number of firm grain, and number of grain per panicle. The unweighted pair group method with arithmetic mean method and principal coordinate analysis by the NTSYS program were applied in this study to classify the nine agro-morphological characters. In addition, tocompare the variations in quantitative characters between O. sativa populations, one-way analysis of variance (ANOVA) was used. The results showed significant differences between the black glutinous rice populations for all quantitative agro-morphological characters. Moreover, some agro-morphological characters showed positive correlations to each other. The dendrogram generated from the analysis process of the agromorphological data divided the O. sativa populations into two groups with unfamiliar features. However, the O. sativa populations assessed exhibited a wide range of variations in morphological characteristics, both within the same population and among other populations with the same strains.

A Malting Barley (Hordeum vulgare L.) Variety, ‘Baegrok’with Resistance to Powdery Mildew and Tolerance to Lodging

Other SectionsAbstract서 언재료 및 방법결과 및 고찰적 요사 사FigureTableReferenceA new malting barley variety, ‘Baegrok’, was developed in 2016 at the National Institute of Crop Science, RDA: Rural development administration by crossing the high-yield ‘Milyang130’ variety with ‘Myoginijo’, which has lodging tolerance and resistance to barley yellow mosaic virus (BaYMV). ‘Baegrok’ is suitable for use in brewing, similar to ‘Hopum’, and has resistance to powdery mildew and tolerance to lodging. From 2014 to 2016, regional yield trials were conducted in four different regions, with ‘Baegrok’ as a breeding line of ‘Iksan176’. The heading dates of ‘Baegrok’ in paddy and upland fields were April 6 and April 11, respectively, 2 days earlier than those of ‘Hopum’. Maturing dates of ‘Baegrok’ in paddy and upland fields were May 16 and May 21, respectively, similar to those of ‘Hopum’. The yield potential of ‘Baegrok’ was approximately 14% and 6% higher than that of ‘Hopum’ in upland and paddy fields. ‘Baegrok’ had a shorter culm length than ‘Hopum’ showing tolerance to lodging. Screening for powdery mildew resistance in the greenhouse showed that ‘Baegrok’ had resistance to powdery mildew, unlike ‘Hopum’ which was susceptible. It also is suitable for use in brewing, similar to Hopum. ‘Baegrok’ showed good grain quality in terms of β-glucan content (3.4%), starch (61.0%), and husk rate (12.7%). Regarding malt quality, ‘Baegrok’ exhibited 75.1% acrospire length, 70.8% friability, 4.4% soluble protein, and 345.8 WK (Windisch-Kolbach) diastatic power, superior to the malt quality of ‘Hopum’. Thus, ‘Baegrok’ is resistant to powdery mildew, tolerant to lodging, and more suitable for brewing. (Registration No. 8399)Keywords : malting barley, variety, malt, powdery mildew, lodging

Morphological characteristics of local rice in Deli Serdang District, North Sumatra, Indonesia

Abstract. Chaniago N, Suliansyah I, Chaniago I, Rozen N. 2021. Morphological characteristics of local rice in Deli Serdang District, North Sumatra, Indonesia. Biodiversitas 23: 883-894. The preservation of local rice is essential to preventing genetic drain. In Deli Serdang District, North Sumatra, Indonesia, local rice is in great abundance. A total of 23 Deli Serdang local rice were collected and studied from coastal to highland areas. This study aims to determine the morphological characteristics of 23 local rice genotypes of Deli Serdang and to obtain superior characters to be developed into superior local varieties. A completely randomized design with three replicates was used in this study. Morphological characteristics of 23 local rice genotypes obtained various characters. The culm length was short to very long; culm diameter was thin to thick; the leaf-blade length was long to very long; leaf-blade width was intermediate to broad; culm number was low to high. The auricle, ligule, and collar were almost completely whitish, except for Sijambi yellowish-green and green, 2-cleft acute ligule shape. The harvest age was medium to deep. The grains were white, straw, gold, brown, brown spots, brown lines, and black. The pericarps were white, light brown, red, and black. Most of the organs indicated broad genetic variability having the opportunity to be developed into superior local varieties. All local rice was scattered into five groups based on morphological markers with a similarity of 32.12%.

INFLUENCE OF ABIOTIC FACTORS ON GROWTH AND DEVELOPMENT OF GIANT BAMBOO (DENDROCALAMUS ASPER) IN BUKIDNON, PHILIPPINES

The study examines the gross morphology of giant bamboo (Dendrocalamus asper) relative to varying elevation, temperature, and relative humidity in five forest areas of Bukidnon province in the Philippines. Results revealed that variations in leaf sizes and the number of nodes and internodes among elevation ranges were not significant. However, the culm length of giant bamboo was significantly higher in the mid-elevation range (644–892 m asl) and lower elevation range (344–447 m asl) compared to culms in higher elevations. In addition, differences in culm diameter and culm thickness were significant showing larger diameter and thicker culms in the mid-elevation range (644–892 m asl) as compared to the higher (1117–1124 m asl) and lower (344–347 m asl) elevation range. The level of phosphorus and nitrogen was the highest in the mid and lower elevation range while potassium level was abundant in the highest elevations. Correlation analysis showed a negative relationship between culm lengths to elevation and relative humidity while mid and top section diameters were negatively correlated to temperature until 892 m asl. Leaf area and leaf width were strongly influenced by phosphorus level. The canonical correspondence analysis showed culm lengths were affected by relative humidity and elevation while the number of nodes and internodes, top and mid-section culm thickness, average diameter and basal section diameters were affected by temperature. Non-metric multidimensional scaling revealed that variation in bamboo morphology occured at the lowest and highest elevation while overall similarity was observed at 600–900 m asl elevation, suggesting an optimal growth for giant bamboo might be within the range.

Phenotypic divergence for morphological and yield-related traits in black oat (Avena strigosa)

This study aims to evaluate the phenotypic divergence among 46 accessions of A. strigosa from Mesoregions Northwest and Northeast of Rio Grande do Sul. The experiment was carried out in the field, in a randomized block design, with three replications. The germplasm was characterized using 40 morphoagronomic, 21 of which were either binary or multicategoric, while 19 were quantitative traits as cycle (days to heading), plant length, peduncle, glume and lemma, and production of biomass and grains. The data were submitted to descriptive, univariate, and multivariate statistical analysis. The accessions were monomorphic in 17 out of 21 among qualitative characters. Vegetative habit, diameter, length, and wall thickness of culm were the main quantitative traits in the discrimination of the accessions. The maximum and minimum dissimilarity, expressed by the generalized Mahalanobis distance, ranged from 2.98 up to 55.71. Based on the magnitude of divergence and performance towards agronomic traits in attributes, some accessions may be incorporated into breeding programs of the species

Agro-morphological characterization based genetic diversity of Indonesian local rice germplasm

The present study was carried out to characterize 103 Indonesian local rice germplasm on the basis of 20 agro-morphological traits. The local rice germplasm originated from Riau and Jambi province in Sumatera island. Principal Component Analysis (PCA) was used to analyzed 11 quantitative data. PCA explained the genetic diversity of the rice germplasm accession. Most of the morphological characters showed variation in different accession. PC1 and PC2 explained about 32.5% and 22.1% of the variability, respectively. PCI and PC2 mostly related with traits such as productive tiller number (PTN), vegetative tiller number (VTN), plant height (PH), and culm length (CL). PCA-Biplot showed accession from Jambi and Riau manage to be separated, even though the PCA percent is only 54.6%. Accession originated from Riau marked by number of tillers (PTN, VTN), and grain weight (GW) traits. Based on cluster analysis, rice germplasm grouped in to 4 main clusters. Most of the accession from Jambi and Riau grouped in the same cluster, which is cluster I. Whereas eight local accessions from Riau grouped in the same cluster separately (cluster II). Two accession which are Padi Jarum (Acc 2711) and Ketan Hitam (Acc 9300) are individually, separated from others.

A Malting Barley (Hordeum Vulgare L.) Variety, ‘Nurimaeg’ with Resistance to Barley Yellow Mosaic Virus and Tolerance to Lodging Stress

Other SectionsAbstract서 언재료 및 방법결과 및 고찰적 요사 사FigureTableReferenceA malting barley variety, ‘Nurimaeg’, was developed with resistance to barley yellow mosaic virus (BaYMV), tolerance to lodging stress, and good brewing quality. ‘Nurimaeg’ was developed by crossing Milyang127 and Miharu gold in 2004. Regional yield trials were conducted for ‘Nurimaeg’ as a breeding line ‘Iksan175’ in four different regions from 2014-2016. It has a type I growth habit, and its average heading and maturity dates were April 12 and May 20, respectively-which were 1 day later than the maturity date of ‘Hopum’ variety. As ‘Nurimaeg’ has a shorter culm length (77 cm) than that of ‘Hopum’, it showed tolerance to lodging stress. This variety possesses the rym5 gene and is resistant to BaYMV. It showed a 42.9 g 1000-grain weight and 90% assortment ratio. The yield potential of ‘Nurimaeg’ was 408 kg/10a, which is approximately 18% higher than that of ‘Hopum’. Analysis of grain quality for malting showed that ‘Nurimaeg’ has high quality of low protein and β-glucan content. Malt quality analysis revealed that it has 72.8% extract, 4.2% soluble protein, 38.9% kolbach index, and 243 WK diastatic power, which all were similar to those of ‘Hopum’. ‘Nurimaeg’ would be suitable for cultivation in the areas of Korea that have a daily minimum temperature of -4℃ in the month of January (Registration No. 7960).Keywords : malting barley, BaYMV resistance, lodging resistance, malt, variety

Assessment of Durum Wheat (Triticum durum Desf.) Genotypes Diversity for the Integrated Production of Bioethanol and Grains

Wheat straw is an abundant source of lignocellulosic biomass that is generally not utilized for biofuel production, nor for other uses. Recent EU renewable energy directive fosters bioethanol production through lignocellulosic sugars fermentation, but the cost of this process is an issue that often depends on biomass characteristics. Lignin is a class of three-dimensional polymers providing structural integrity of plant tissues. Its complex structure, together with hemicelluloses and uronic acids content, could affect the ability of hydrolyzing biomass to fermentable sugars. To get insights into this variation, a set of 10 durum wheat genotypes was analyzed to determine variation of straw digestibility to fermentable sugars. The results showed that the lignin content was the major factor determining the recalcitrance to enzymatic process. The analysis of Spearman’s correlation indicated that the sugar released after enzymatic hydrolysis had a negative connection with the lignin content, while it was positively correlated with the culm length. The possible role of other cell wall components, such as arabinose and uronic acids, was also discussed. This work aimed at analyzing the diversity of lignocellulosic digestibility to fermentable sugars of wheat straw in a small germplasm collection. Some of the selected genotypes were characterized by high sugars digestibility and high grain yield, characteristics that could make biorefining of wheat straw profitable.

Hd1 Allele Types and Their Associations with Major Agronomic Traits in Korean Rice Cultivars.

Optimizing flowering time in crop plants is critical for maximizing yield and quality under target environments. While there is a wide range of heading date variation in Korean rice cultivars, the underlying gene mechanisms are unclear. Here, we sequenced the protein coding regions of Hd1, the major rice heading date gene, from 293 Korean rice cultivars and investigated the associations between Hd1 allele types and major agronomic traits under four different environments. There were four functional Hd1 and five nonfunctional hd1 alleles distributed among the 293 Korean rice cultivars. The effects of the Hd1 allele types were highly significant for days to heading in all four environments, explaining 51.4–65.8% of the phenotypic variation. On average, cultivars carrying nonfunctional hd1 headed 13.7 days earlier than those carrying functional Hd1. While the Hd1 allele types exhibited highly significant effects on culm length and protein content under all four environments, the differences between cultivars carrying Hd1 and hd1 were minimal. The effects of the Hd1 allele types on amylose content were significant in only one of the four environments. Our results provide useful information for fine-tuning rice heading dates by utilizing different Hd1 alleles in rice breeding programs.

Variability, Heritability and Genetic advance of introduced upland rice genotypes at Fogera in North Western Ethiopia

Variability, heritability and genetic advance are basic in order to provide information for plant breeding programs. Forty nine upland rice genotypes were tested in 7*7 simple lattice design at Fogera in Wereta station of Adet Agricultural Research Center in 2012/13. The objectives of the study were to estimate the genetic variability, heritability and genetic advance of the genotypes tested. Analysis of variance revealed that there was highly significant difference among the 49 genotypes for all the characters studied. Accessions IR 78937-B-3-B-B-1 and IR 78937-B-3-B-B-2 had the highest yield with a score of 5374.5 kg/ha and 5305.6 kg/ha respectively. The high yielding genotype IR 78937-B-3-B-B-1 had a yield advantage of 57% and 22.2%, respectively, as compared to standard checks Nerica-4 and Hidasie. Phenotypic coefficient of variation (PCV) values ranged from 2.5% for panicle length to 49.98% for number of spikelet per panicle. While the genotypic coefficient of variation (GCV) ranged from 2.4 % for panicle length to 47.6 % for number of spikelet per panicle. Number of tiller per plant (22.47%), number spikelet per panicle (49.98%), thousand seed weight (25.56%) and yield (23.93%) had higher PCV values. The PCV values for flag leaf length (14.79%), flag leaf width (16.12%), and culm length (16.42%) and number of panicle per plant (16.32%) were medium. Flowering cycle (7.81%), maturation cycle (2.9%), and panicle length (2.5%) had lower PCV values. GCV values were low for flowering cycle (7.21%), maturation cycle (1.82%) and panicle length (2.4%); medium for flag leaf length (14.26%), flag leaf width (15.39%), culm length (15.19 %) and number of panicle per plant (15.72%); high for number of tillers per plant (22.18 %), yield (23.07%), thousand seed weight (25.18%) and number of spikelet per panicle (47.60%). The high GCV values of these characters suggest that genetic impact is higher and environmental influence is lower. This study generally had indicated that there was significant genetic variability or divergence among the genotypes. Thus, the improvement program of the upland rice genotypes through direct selection rather than a lengthy crossing program is recommended.

The effect of seasonal flooding and livelihood activities on retention of nitrogen and phosphorus in Cyperus papyrus wetlands, the role of aboveground biomass

With growing demand for food production in Africa, protecting wetlands and combining increased agricultural production with conservation of the ecological integrity of wetlands is urgent. The role of aboveground biomass of papyrus (Cyperus papyrus) in the storage and retention of nitrogen (N) and phosphorus (P) was studied in two wetland sites in East Africa under seasonally and permanently flooded conditions. Nyando wetland (Kenya) was under anthropogenic disturbance from agriculture and vegetation harvesting, whereas Mara wetland (Tanzania) was less disturbed. Maximum papyrus culm growth was described well by a logistic model (regressions for culm length with R2 from 0.70 to 0.99), with culms growing faster but not taller in Nyando than in Mara. Maximum culm length was greater in permanently than in seasonally flooded zones. Total aboveground biomass was higher in Mara than in Nyando. The amounts of N and P stored were higher in Mara than in Nyando. In disturbed sites, papyrus plants show characteristics of r-selected species leading to faster growth but lower biomass and nutrient storage. These findings help to optimize management of nutrient retention in natural and constructed wetlands.

Bamboo as a Sustainable Building Material—Culm Characteristics and Properties

Bamboo culm is a renewable and lightweight material with high strength, particularly tensile strength. It is well accepted that bamboo culms have played a significant role in architecture because of their sustainable contribution. The culm characteristics and properties of three-year-old bamboo from five species (Dendrocalamus asper, Dendrocalamus sericeus, Dendrocalamus membranaceus, Thyrsostachys oliveri, and Phyllostachys makinoi) were investigated. The results show that each bamboo species has different culm characteristics along with culm length. Culm size, particularly the outer culm diameter and culm wall thickness, affects the ultimate load. These results confirm that a bigger culm with a thicker wall could receive more load. D. asper received the highest ultimate load, while T. oliveri received the lowest ultimate load. However, when calculating the test results for stress (load per cross-section area), P. Makinoi showed excellent mechanical properties, while D. asper showed the worst mechanical properties. This research promotes bamboo’s appropriate use for building applications and as a more sustainable material for architecture.

Effect and Compatibility of Phosphite with Trichoderma sp. Isolates in the Control of the Fusarium Species Complex Causing Pokkah Boeng in Sugarcane

Sugarcane, a highly productive crop, is frequently challenged by different biotic agents, such as the pokkah boeng disease that can cause drastic yield losses of up to 40%. This airborne fungal disease is caused by various Fusarium species integrated into a complex. Integrating novel compounds and biological control agents is of paramount importance to cope with these fungi in sustainable systems. In this study, we aimed to evaluate the effect and compatibility of phosphite (Phi) and Trichoderma sp. in the control of Fusarium sp., in vitro and in planta. Using in vitro tests, we evaluated the effects of Phi (0, 500, 1000, 2000, 4000, and 8000 µg mL−1) and the compatibility of Phi + Trichoderma (isolates Taz 001, 013, and 016) on the pathogen complex. Using in planta tests, we evaluated the compatibility of Phi + Trichoderma (Taz-016) in the control of Fusarium in sugarcane plants under greenhouse conditions. A synergistic effect of Phi + Trichoderma was observed in vitro on the control of the pathogen, especially when combining 1000 µg mL−1 + Trichoderma Taz-016. In the in planta trial, combining 4000 µg mL−1 Phi + Trichoderma Taz-016 showed the best control of Fusarium infection, improving plant height, culm length and leaf dry weight.

Clonal performance of Scirpus yagara in multiple levels of substrate heterogeneity and submergence

Abstract Aims Environmental heterogeneity affects the performance of clonal aquatic plants. Few researchers integrated two aspects of heterogeneity into the study of clonal plant ecology. The aims of the present study are to (i) test whether different substrate heterogeneity and submergence exert similar effects on plant performance and (ii) explore the foraging behaviour. Methods In this study, Scirpus yagara was subjected to multiple levels of substrate heterogeneity and submergence. Substrate treatments included one homogeneous substrate and three heterogeneous substrates (two-patch, four-patch and eight-patch). Water level treatments included 0, 10 and 30 cm. Traits including ramet number, generation number, leaf number, bulb number, ramet height, culm length, rhizome length, clonal radius, spacer length, spacer thickness, total biomass, biomass of bulbs and biomass per bulb were measured. Important Findings Deeper water levels significantly reduced variables associated with growth such as ramet number, generation number, leaf number and bulb number, while substrate patchiness induced significant variations in traits such as spacer length and spacer thickness. Significant interactive effects of the two factors were found for ramet number, leaf number and spacer length. Scirpus yagara showed colonization towards the lake sediment patch in two-patch and four-patch substrates, and more structures were placed in the lake sediment patch. Especially for the two-patch substrate, all structures occupied the lake sediment patch. Two-sided intrusion was observed in the eight-patch substrate, which induced an even allocation of structures in different patches. The foraging behaviour was correlated with the patch size.

The dominance model for heterosis explains culm length genetics in a hybrid sorghum variety

Heterosis helps increase the biomass of many crops; however, while models for its mechanisms have been proposed, it is not yet fully understood. Here, we use a QTL analysis of the progeny of a high-biomass sorghum F1 hybrid to examine heterosis. Five QTLs were identified for culm length and were explained using the dominance model. Five resultant homozygous dominant alleles were used to develop pyramided lines, which produced biomasses like the original F1 line. Cloning of one of the uncharacterised genes (Dw7a) revealed that it encoded a MYB transcription factor, that was not yet proactively used in modern breeding, suggesting that combining classic dw1or dw3, and new (dw7a) genes is an important breeding strategy. In conclusion, heterosis is explained in this situation by the dominance model and a combination of genes that balance the shortness and early flowering of the parents, to produce F1 seed yields.

Investigating the Underlying Effect of Thermal Modification on Shrinkage Behavior of Bamboo Culm by Experimental and Numerical Methods.

This study probes into the root cause of split in thermally modified bamboo culm by investigating the underlying effect of thermal contraction with respect to its orthotropic nature by experimental and numerical methods while concurrently monitoring the chemical variation of its structure by Fourier transformed infrared spectroscopy (FTIR). In first part of this study, a non-linear increase in dimensional and weight changes of small clear bamboo specimens were observed with increasing temperature. The dimensional changes in the radial and tangential directions significantly exceeded that in the longitudinal direction. From FTIR results, shrinkage effect between 150 °C to 200 °C was associated with weight loss engendered by reduction in weakly bound water and increase in desorption of water content while alteration of its mechanical properties was attributed to changes in cellulose, hemicellulose, and lignin. From results of finite element method (FEM), the graded variation in thermal expansion coefficient, which showed the formation of a narrowed region of strain concentration corresponding to longitudinal crack propagation, was associated with the inducement of internal forces, namely tensile and compressive forces, at specific regions along the culm length. The results of this study can be useful to achieve optimized durability in modified bamboo for construction.

Profiling of Phenolic Compounds Composition, Morphological Traits, and Antioxidant Activity of Miscanthus sacchariflorus L. Accessions

Miscanthus sacchariflorus is a potential source of sustainable biofuel and other bioactive compounds. The high adaptive range of M. sacchariflorus may cause variation in its morphological traits and phytochemical composition. Although some metabolites have been reported from M. sacchariflorus, little is known about its phenolic compound composition and antioxidant or oxidant properties. This study evaluated the morphological traits, antioxidant properties, and phenolic compound profile of M. sacchariflorus collected from various regions of China, Korea, Japan, and Russia. The antioxidant potential of the leaf extracts of various accessions of M. sacchariflorus was estimated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and 2,2′-azinobis 3-ethylbenzothiazoline-6-sulfonate (ABTS). An extensive study of the antioxidant activity and phenolic compounds of M. sacchariflorus obtained from different locations in four different countries could provide a comprehensive catalogue of the phytoconstituents and antioxidant properties of M. sacchariflorus accessions to consumers and nutraceutical industries. A total of 22 phenolic compounds were identified and quantified, among which p-coumaric acid, ferulic acid, p-hydroxybenzoic acid, chlorogenic acid, vitexin, and luteolin were the most dominant phytochemical compounds detected in the majority of the accessions. The antioxidant potential (DPPH) of the leaf extracts of all of the accessions ranged from 28.85 ± 1.53 µg mL−1 in MS-447 to 99.25 ± 1.63 µg mL−1 in MS-190. The antioxidant properties (ABTS) of the leaf extracts of all accessions ranged from 25.65 ± 2.06 in MS-258 to 83.62 ± 2.02 in MS-271. Pearson’s correlation analysis showed a significant and positive correlation between antioxidant activity and total phenolic content, and total flavonoid content varied widely among M. sacchariflorus accessions from the four geographical study regions. A strong and positive association was observed between DPPH with total phenolic content and total flavonoid content. Moderately positive correlations were observed between DPPH scavenging activity with gentisic acid, p-hydroxybenzoic acid, chlorogenic acid, p-coumaric acid, rutin, and quercetin (r = 0.385, r = 0.379, r = 0.362, r = 0.353, r = 0.490, and r = 0.372, respectively), suggesting that phenolic compounds are major contributors to the antioxidant potential of M. sacchariflorus. Thirty-two accessions collected from four different countries (China, Korea, Japan, and Russia) were characterized for 17 quantitative morphological traits. A wide range of diversity was observed in the morphological traits, with plant height ranging from 18.00 ± 1.00 cm to 163.20 ± 4.00 cm. Plant height was significantly correlated with biomass yield (fresh weight; r = 0.439, p < 0.05) and also had moderately positive correlations with culm length (r = 0.356, p < 0.05). Culm length was moderately correlated with the biomass yield fresh weight (r = 0.419*, p < 0.05) and the biomass yield dry weight (r = 0.425*, p < 0.05); however, it exhibited weak and negative correlations with compressed plant circumference (CCirc) (r = −0.374, p < 0.05) and total culm node number (TCmN) (r = −0.440, p < 0.05). Principal components analysis was performed to assess the variation in 17 morphological traits in 32 accessions of M. sacchariflorus. The first two principal components explained 51.24% of the morphological variations. A dendrogram generated from unweighted pair group method with arithmetic mean (UPGMA) clustering based on morphological characters was not found to be consistent with another dendrogram based on phytochemicals. In both cases, the number of studied accessions collected from different geographical regions grouped into two major groups. However, no clear correlation between these two different approaches was found. The substantial variation in the morphological traits, bioactive properties, and phenolic compounds among the accessions may provide useful information for breeding programs attempting to obtain M. sacchariflorus varieties with improved phenolic compounds traits and improved bioactive properties.

Managing flowering time in Miscanthus and sugarcane to facilitate intra- and intergeneric crosses.

Miscanthus is a close relative of Saccharum and a potentially valuable genetic resource for improving sugarcane. Differences in flowering time within and between Miscanthus and Saccharum hinders intra- and interspecific hybridizations. A series of greenhouse experiments were conducted over three years to determine how to synchronize flowering time of Saccharum and Miscanthus genotypes. We found that day length was an important factor influencing when Miscanthus and Saccharum flowered. Sugarcane could be induced to flower in a central Illinois greenhouse using supplemental lighting to reduce the rate at which days shortened during the autumn and winter to 1 min d-1, which allowed us to synchronize the flowering of some sugarcane genotypes with Miscanthus genotypes primarily from low latitudes. In a complementary growth chamber experiment, we evaluated 33 Miscanthus genotypes, including 28 M. sinensis, 2 M. floridulus, and 3 M. ×giganteus collected from 20.9° S to 44.9° N for response to three day lengths (10 h, 12.5 h, and 15 h). High latitude-adapted M. sinensis flowered mainly under 15 h days, but unexpectedly, short days resulted in short, stocky plants that did not flower; in some cases, flag leaves developed under short days but heading did not occur. In contrast, for M. sinensis and M. floridulus from low latitudes, shorter day lengths typically resulted in earlier flowering, and for some low latitude genotypes, 15 h days resulted in no flowering. However, the highest ratio of reproductive shoots to total number of culms was typically observed for 12.5 h or 15 h days. Latitude of origin was significantly associated with culm length, and the shorter the days, the stronger the relationship. Nearly all entries achieved maximal culm length under the 15 h treatment, but the nearer to the equator an accession originated, the less of a difference in culm length between the short-day treatments and the 15 h day treatment. Under short days, short culms for high-latitude accessions was achieved by different physiological mechanisms for M. sinensis genetic groups from the mainland in comparison to those from Japan; for mainland accessions, the mechanism was reduced internode length, whereas for Japanese accessions the phyllochron under short days was greater than under long days. Thus, for M. sinensis, short days typically hastened floral induction, consistent with the expectations for a facultative short-day plant. However, for high latitude accessions of M. sinensis, days less than 12.5 h also signaled that plants should prepare for winter by producing many short culms with limited elongation and development; moreover, this response was also epistatic to flowering. Thus, to flower M. sinensis that originates from high latitudes synchronously with sugarcane, the former needs day lengths >12.5 h (perhaps as high as 15 h), whereas that the latter needs day lengths <12.5 h.