Explore the vast range of titles available.

Immature embryos of F1 progeny resulting from taxonomically wide hybridizations require tissue culture using complex media to mature, grow and develop into normal and healthy plants. To gain insight as to how progeny of wide-crosses between wild and domestic Triticum species, 12 domestic varieties (Al-Eiz, Babel, Bedhaa, Entisar, Hadbaa, IPA 99, Latifia, Nour, Rabia, Sally, Sham 6, Tamoz 2) were used to determine the genotype response to culture media type. Immature embryos the aforementioned wheat varieties were screened on four media (Murashige and Skoog; MS full strength, ½ strength MS, Gamborg B-5; B-5 full strength, and ½ strength B-5) to determine performance when used as a female in a cross with wild species. The experiment used a completely randomized design with six replications. Traits recorded were final germinations percentage (FGP), shoot length (SL), root length (RL), and root number (RN). Results indicated significant variety x media interaction for all traits studied. Despite the interaction, in a practical sense, all varieties performed adequately on ½ B-5 and varieties Al-Eiz, Entisar, Hadbaa, and Latifia performed well on any of the four media. Tamoz 2 behaved recalcitrantly on all media tested. Data from this study indicated genetic variability among these wheat varieties caused substantial differences in response to each type of media.

Bermudagrass ( Cynodon spp.) breeding and cultivar development is hampered by limited information regarding its genetic and phenotypic diversity. To explore diversity in bermudagrass, a total of 206 Cynodon accessions consisting of 193 common bermudagrass ( C. dactylon var. dactylon ) and 13 African bermudagrass ( C. transvaalensis ) accessions of worldwide origin were assembled for genetic characterization. Genotyping-by-sequencing (GBS) was employed for genetic marker development. With a minor allele frequency of 0.05 and a minimum call rate of 0.5, a total of 37,496 raw single nucleotide polymorphisms (SNPs) were called de novo and were used in the genetic diversity characterization. Population structure analysis using ADMIXTURE revealed four subpopulations in this germplasm panel, which was consistent with principal component analysis (PCA) and phylogenetic analysis results. The first three principal components explained 15.6%, 10.1%, and 3.8% of the variance in the germplasm panel, respectively. The first subpopulation consisted of C . dactylon accessions from various continents; the second subpopulation was comprised mainly of C. transvaalensis accessions; the third subpopulation contained C. dactylon accessions primarily of African origin; and the fourth subpopulation represented C. dactylon accessions obtained from the Oklahoma State University bermudagrass breeding program. Genetic diversity parameters including Nei’s genetic distance, inbreeding coefficient, and Fst statistic revealed substantial genetic variation in the Cynodon accessions, demonstrating the potential of this germplasm panel for further genetic studies and cultivar development in breeding programs.

Associative nitrogen (N2)‐fixation (ANF) by bacteria in the root‐zone of perennial bioenergy grasses has the potential to replace or supplement N fertilizer and support sustainable production of biomass, but its application in marginal ecosystems requires further evaluation. In this study, we first combined both greenhouse and field experiments, to explore the N2 fixation effects of three temperate feedstocks Miscanthus × giganteus (giant miscanthus, Freedom), Panicum virgatum (switchgrass, Alamo), and Saccharum sp. (energycane, Ho 02‐147). In field studies across three growing seasons, plant and soil pools of candidate feedstocks were partially composed of N derived from the atmosphere (Ndfa). Energycane, giant miscanthus, and switchgrass were estimated to derive >30%, %Ndfa. Greenhouse studies were also performed to trace isotopically labeled 15N2 into plant biomass and soil pools. Evidence for Ndfa was detected in all three feedstock grasses (using reference 15N of soil, chicory, and sorghum, δ15N~+7.0). Isotopically labeled 15N2 was traced into biomass (during grass elongation stage) and soil pools. Extrapolation of rates during the 24 hr labeling period to 50 days estimated 30%–55% of plant Ndfa, with the greatest Ndfa for energycane. The findings of the field natural abundance and greenhouse 15N2 feeding experiments provided complementary evidence that perennial bioenergy grasses have the potential to support relatively high rates of ANF, and accumulate diazotroph‐derived N into biomass when grown on non‐fertilized soil. Associative nitrogen (N2)‐fixation by bacteria in the root‐zone of perennial bioenergy grasses have the potential to replace or supplement nitrogen fertilizer and support sustainable production of feedstock biomass. A 3 year field 15N natural abundance and a greenhouse enriched 15N feeding experiment were conducted to assess the possibility of bacterial supply of atmospheric nitrogen to feedstock grasses. It was shown that temperate bioenergy grasses switchgrass, miscanthus, and energycane can attain ~30%–50% of nitrogen from atmospheric N2 via bacterial diazotrophs.

Saccharum is relatively new to 33° N latitude. S. spontaneum readily hybridizes with commercial sugarcane (Saccharum spp.) and lends cold tolerance and greater yield to the hybrid progeny, called energycane. Since 2007, there have been numerous new hybrid and backcross energycane genotypes developed but there is a paucity of information about them. Twenty energycane genotypes were tested in the first season of growth from cane propagules (plant cane; PC) against Ho 02-113 (a control) for two site-years in northcentral Mississippi. Grand (exponential) growth continued into October. The prevailing paradigm is that tonnage is what matters. Except for percentage cellulose, all factors tested (dry matter yield, extractable juice volume, °Brix, theoretical ethanol from fermentation, theoretical ethanol from cellulose, and total theoretical ethanol) were greater from the second site-location compared to the first. Dry matter yield (DMY) and total theoretical ethanol yield (TTEY) were moderately correlated. Over the two years of this test only Ho 14-9213 exceeded in mean DMY of Ho 02-113. Sixteen of the 19 test genotypes in this test equaled or exceeded the mean TTEY of Ho 02-113.

Energycane and biomass sorghum are two of the most promising cellulosic energy crops in the southeastern US. Research on these two energy crops has focused mainly on biomass production, and there is a lack of knowledge on their ability to promote biodiversity and ecosystem services. This paper presents results from a comprehensive study on ground-active arthropod diversity in seven sites across five states in the southeastern US (Florida, Georgia, Louisiana, Mississippi, and Texas). Pitfall traps were deployed four times during each crop season for energycane, biomass sorghum, and a local reference conventional crop from 2020 to 2022. Arthropod abundance (individuals/(trap × day)) values were 4.9 ± 0.46, 3.7 ± 0.18, and 2.6 ± 0.16 (mean ± stderr) for conventional crops, biomass sorghum, and energycane, respectively, with a significant difference found only between conventional crops and energycane. Individuals were identified to arthropod orders, and Hill’s diversity indices were calculated based on the number of individuals in each arthropod order instead of the number of individuals in each arthropod species. Order-based arthropod richness values were 5.3, 5.2, and 4.8 for biomass sorghum, conventional crops, and energycane, with significant difference found only between biomass sorghum and energycane. There was no significant difference in the order-based Shannon diversity and Simpson diversity between the three crop types. The effective number of arthropod orders for the two energy crops decreased from 5.0 to 3.4 to 2.9 with increasing order of diversity from arthropod richness to Shannon diversity to Simpson diversity. The explained variability by environmental factors also decreased with increasing Hill’s order of diversity. The results from this study indicate no significant advantage in order-based arthropod diversity in growing biomass sorghum and energycane. This research fills a critical knowledge gap in understanding the impacts of cellulosic energy crop production on biodiversity and ecosystem services.

Salinity is one of the most important challenges facing future global barley (Hordeum vulgare L.) productivity, as it causes major reduction in germination, growth, grain yield, and quality. Screening germplasm for salinity tolerance at germination is vital to breeding programs because germination is the first stage of plant growth and occurs near the soil surface where salt can accumulate in high concentrations. This experiment was conducted to assess salinity tolerance of 249 genotypes (64 diploid (2×) H. vulgare crosses; 174 tetraploid (4×) H. vulgare crosses; and 11 parents) at the seed germination stage. Salinity treatments applied at imbibition included concentrations of 0, 100, 200, and 300 mM salinity and were maintained for 10 d. Analysis of variance of all families indicated significant (P ≤ .001) genotype × salinity interaction for final germination percentage (FG%), corrected germination percentage (CG%), and germination index (GI) at all treatment levels, indicating high genetic variation for salinity tolerance among screened genotypes. The mean of all measured parameters (FG%, CG%, and GI) decreased as salinity concentration increased. These responses can be used to identify genotypes with salinity tolerance at germination. At 300 mM salinity, progenies in 2× Families 1 and 2 were 14.3 and 12.5% saline tolerant, respectively. A total of 29 progenies from 4× families were tolerant to 300 mM treatment at germination. These progenies would have an economic value for improving barley tolerance for salinity. Core Ideas Effective screening for saline tolerance at germination requires multiple‐parameter evaluation. Diploid and tetraploid Hordeum progeny offer wide genetic value for saline tolerance breeding. High variation in response to salinity exists within and among Hordeum interspecific hybrids.

Salinity is a critical challenge facing productivity of barley around the world, necessitating the development of salinity tolerant varieties. Screening genotypes of two barley species during germination and seedling growth stages was conducted to identify genotypes with superior performance under saline stress conditions. Five genotypes of domestic barley (Hordeum vulgare L.) and six of wild barley (H. bulbosum) were used in this study. Genotypes were germinated in solutions of 0, 1.0, 1.5, and 2.0% NaCl (0, 171, 257, and 342 mM NaCl). Shoot and root length were recorded 10 d after germination. Upon reaching the three‐leaf stage, seedlings were irrigated with 500 mM NaCl solution for 3 wk to evaluate salt tolerance using the growth index. The analysis of variance showed there was a high genetic variation among genotypes. Only genotypes PI220054, PI227242, and PI420909 of wild barley species germinated at the 2% NaCl salinity level. All domestic barley genotypes failed to germinate at 2% NaCl salinity and showed reduction of root and shoot length greater than wild barley genotypes under saline conditions. Mean root and shoot lengths decreased as the level of NaCl increased for all genotypes. This condition was more intense in domestic than wild barley genotypes. Seedling screening showed PI268243 had the greatest growth index compared with the other genotypes. The PI227242 genotype had the greatest growth index among wild barley genotypes. Regression analysis indicated that there was no relationship between salt tolerance at germination and seedling growth stages.

Selenium (Se)‐affected stormwater runoff raises concerns about potential downstream impact of Se on aquatic ecosystems. Unplanted (UNP) detention ponds augmented with cattail (Typha angustifolia L.; CAT) and duckweed (Lemna minor L.; DWD) may provide a solution for continuous, rapid abatement of Se‐affected runoff. This research was conducted to evaluate the efficacy of CAT or DWD and determining the distribution of Se within a continually flooded detain and drain system. Microcosms containing 3 kg of soil planted to either one CAT, 25 g fresh DWD, or left unplanted (UNP, control) were flooded with a 3‐L solution at 40 μg Se L−1, as sodium selenate (Na2SeO4), or a zero Se control. Over two 10‐d flood–discharge cycles (FDCs), plants in microcosms were evaluated in growth chambers maintained at 30 °C under a 12‐h photoperiod with 400 μmol m−2 s−1 irradiance. Initial and final water, soil, plant, and granular activated charcoal (GAC) were analyzed for total [Se] with inductively coupled plasma–mass spectroscopy (ICP–MS). Data were analyzed with PROC GLM (SAS EG 7.1) at α = .05. Within 10 d after Se application, CAT and DWD decreased aqueous Se from 40 μg Se L−1 to below the 11.8 μg Se L−1 threshold. Selenium recovery ranged between 75 and 100% of the applied Se. In continually flooded systems, the primary elimination pathway appears to be associated with the soil solid phase. Cattail and DWD are suitable species for constructed wetland phytoremediation of Se‐affected runoff. The microcosm design presented may be useful for future evaluations. Core Ideas Selenium‐affected runoff threatens the environmental quality of aquatic ecosystems. Within 10 d of rainfall, Se‐affected runoff must be discharged below 11.8 μg Se L−1. Constructed wetlands can provide continuous, rapid abatement of Se‐affected runoff. Seventy‐five to one hundred percent recovery of applied Se was associated with the soil solid phase. Within 10 d, cattail and duckweed can decrease aqueous Se from 40 μg Se L−1 to below 11.8 μg Se L−1.

Increased salinity from irrigation and poor drainage has led to reduced production in semi‐arid and arid irrigated areas of the world. The narrow genetic variation among domestic barley (Hordeum vulgare L.) genotypes slows progress in developing varieties tolerant to biotic and abiotic stresses. A wild barley relative (H. bulbosum L.) is a genetic resource with tolerance to multiple stress conditions, especially salinity. New germplasm added to the USDA barley collection allows novel breeding opportunities. However, crosses between these species require embryo rescue. Crosses were made between diploid and tetraploidized domestic barley ♀ and tetraploid bulbous barley ♂. Immature embryos were rescued and placed on Murashige and Skoog (MS) or Gamborg's B‐5 (B‐5) media (no plant growth regulators, PGRs). Analysis of variance of families showed significant effects for the genotype × medium interactions, indicating each genotype responded to each medium type independently. Significant effects were observed for some traits due to both genotype and medium; and significant effects between media for some traits were observed indicating that those traits were affected by media type. Murashige and Skoog was found to be the better medium for most crosses compared to B‐5. Generally, results from this study indicated that it is difficult to draw broad conclusions about the most suitable medium composition for a broad spectrum of genotypes due to individual genotypes responding differently to the media type. Subsequent manuscripts by these authors will address the success of fertile crossed  progeny.

Salinity is one of the most detrimental abiotic stresses affecting crop productivity worldwide. To identify barley (Hordeum vulgare L.) genotypes with satisfactory production under increased salinity, screening must focus on multiple phenological stages, specifically the earliest stages (germination and seedling), when plants are most vulnerable to stress. This experiment was conducted in a greenhouse to assess salinity tolerance of 161 genotypes (34 genotypes of 2× H. vulgare crosses; 116 genotypes of 4× H. vulgare crosses, and 11 parents). Beginning at the third leaf stage, seedlings were irrigated with solutions of 0, 100, 200, and 300 mM NaCl for 21 d. Analysis of variance showed significant effects due to genotype, salinity level, and their interaction for shoot dry weight (SDW). Overall, SDW showed negative association with plant height, whereas it was positively associated with tiller number, fertility, 100‐seed weight, and grain yield. Mean SDW of all families decreased as salinity treatment level increased. Families varied in SDW and salinity susceptibility index (SSI) at 300 mM salinity treatment. Diploid Families 2 and 3 had the greatest SDW and lowest SSI (<1). Thirty percent of crosses from tetraploid Family 2 yielded the greatest SDW, whereas the same proportion of crosses from tetraploid Family 4 showed the greatest salinity tolerance as measured by SSI. These crosses, as well as the female parents, are valuable germplasm for improving salinity tolerance in barley breeding programs. Core Ideas High genetic variation exists within and among H. vulgare × H. bulbosum families. Overwhelmingly, barley families responded similarly to increasing salinity. Increasing salinity at the seedling stage significantly decreases barley productivity. Final germination percentage and shoot dry weight are critical for assessing salt tolerance. No relationship between saline tolerance at germination and seedling growth stages.