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Severe water stress is responsible for reducing plant growth and reproduction. This study aimed to evaluate the physiological and biochemical mechanisms associated with the tolerance of two genotipes of bahiagrass (Paspalum notatum Flügge) with different ploidy level to water deficit and flooding at the reproductive stage. Photosynthetic performance of diploid and tetraploid plants was not affected by flooding. In contrast, the water deficit decreased stomatal conductance, increased leaf temperature, and resulted in a decrease in the assimilation rate of the two genotypes. Despite the greater activities of antioxidant enzymes, flooded roots accumulated hydrogen peroxide and malondialdehyde. Roots of plants exposed to water deficit maintained an accumulation of biomass similar to that of control plants; however, with higher levels of total phenol content, total soluble sugars and proline. Diploid plants subjected to flooding had more inflorescences, however, the drought reduced the total number of filled florets per plant. Less starch degradation allows the maintenance and recovery of biomass in the tetraploid genotype, which allows it to maintain its reproductive performance even under drought conditions. Overall, the synthesis of osmoprotectants and activation of antioxidant machinery are important strategies in the tolerance of bahiagrass to water stress at the reproductive stage.

Maize brown sheath spot (MBSS), a new disease of maize, was discovered while surveying for maize leaf and sheath blight diseases in the Indian states of Assam, Jharkhand, Meghalaya, Manipur, and Odisha. Maize is the third most important cereal after rice and wheat in India. Unlike banded leaf and sheath blight disease caused by Rhizoctonia solani, MBSS symptoms on maize were discrete and limited to sheaths only. Symptoms of MBSS in the field were initially water-soaked necrotic lesions of 1 to 2 cm in diameter on the lowermost leaf sheaths, which then progressed to the upper sheaths. Lesions coalesced and covered approximately 2 to 5% of the sheath area. Infected dried lower leaves were shed, whereas infected upper leaves remained on the stem. The pathogen was isolated, characterized morphologically, pathologically, and molecularly, and identified as Waitea circinata var. prodigus, a basidiomycete known to cause basal leaf blight of seashore paspalum. The internal transcribed spacer (ITS) sequence 2 (ITS2) of rDNA from MBSS isolates formed a well supported clade with known W. circinata var. prodigus isolates. Molecular morphometric analysis of the ITS2 regions of the five known varieties of W. circinata detected distinguishing variations in GC content, compensatory base changes (CBCs), hemi- CBCs, indels, and altered base-pairing of helices. Variation in these characteristics may indicate that varieties are distinct biological species within W. circinata sensu lato. The geographical distribution and potential impacts of MBSS on the maize crop in India necessitate further investigations of pathogen identification and disease management.

The goal of this study was to evaluate growth and nutritional characteristics of seven warm season grasses, including several natives, produced under simulated partial shading (50%) typical of loblolly pine silvopastoral systems in the southeastern United States. Forages included ‘Tifton 9’ bahiagrass (Paspalum notatum), ‘Tifton 85’ bermudagrass (Cynodon dactylon), ‘Alamo’ switchgrass (Panicum virgatum), ‘Kaw’ Big Bluestem (Andropogon gerardii), ‘Americus’ Indiangrass (Sorghastrum nutans), ‘Harrison’ Florida paspalum (Paspalum floridanum), and Nacogdoches Eastern gamagrass (Tripsacum dactyloides). Shade affected several quality parameters, including crude protein (CP) (p

Turfgrass lawns demand high inputs of nitrogen (N) to maintain attractive and functional landscapes. Endophytic diazotrophs have a high potential to increase N in the host plant and promote growth ...

The twolined spittlebug, Prosapia bicincta (Say) (Hemiptera: Cercopidae), is an important insect pest of turfgrass in the eastern United States. Although twolined spittlebug infests most warm-season turfgrasses, the influence of low and high relative humidity (RH) on the expression of feeding damage in warm-season turfgrasses is not well understood. Experiments were conducted in which five warm-season turfgrasses were caged with ten twolined spittlebug adults and exposed to 40% and 95% RH for 5 days. The extent of damage was measured with a SPAD meter (chlorophyll content), and ratings of greenness, yellowness, and purpleness were obtained using a scale system. Physiological parameters such as stomatal conductance (GS), photosynthesis (A), evapotranspiration (E), and water use efficiency (WUE) were measured. Under both 40 and 95% RH, bermudagrass [Cynodon L.C. Rich, spp.] exhibited injury symptoms after twolined spittlebug exposure. The rate of A was lower in the presence of twolined spittlebug in bermudagrass under both RHs. Injury symptoms in centipedegrass [Eremochloa ophiuroides (Munro) Hack] were only observed under high-RH conditions, whereas in zoysiagrass [Zoysia matrella (L.) Merrill.] symptoms were only observed under low RH. Minimal levels of symptom expression were observed in St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze], and no feeding symptoms were observed in seashore paspalum [Paspalum vaginatum Sw.] under low RH. Overall, the presence of twolined spittlebug A was influenced by high RH, whereas WUE was affected by low RH in most of the turfgrass genotypes.

Growth and developmental parameters of the fall armyworm, Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae), were evaluated on 41 new zoysiagrass taxa (Zoysia spp. Willd.), which belong to an increasingly popular group of warm-season turfgrasses, in comparison with 5 commercially available zoysiagrass taxa and 1 known susceptible Paspalum L. taxon. Results from two no-choice growth chamber trials indicated that the new Zoysia japonica Steud. taxa were unfavorable for the development of fall armyworm larvae in general compared with the susceptible Paspalum taxon. This was evidenced by significantly lower larval and pupal weights and survival and longer time to pupation and adult emergence, pointing to antibiosis in these zoysiagrass taxa. The new Zoysia matrella (L.) Merr., Zoysia macrostachya Franch. & Sav., and Zoysia sinica Hance taxa seemed more favorable than Z. japonica taxa, as evidenced by numerically higher larval and pupal weights and survival and shorter duration to pupation and adult emergence. Taxa that consistently showed low larval survival were identified for further testing.

This study quantified K uptake kinetic parameters in grass species Paspalum notatum, Paspalum urvillei and Axonopus affinis to associate them with growth. Ten milliliters (10 ml) of nutrient solution were collected in two-liter pots - with five repetitions in 24 hours - in order to determine K concentrations in the samples. Shoot and root dry matter, root length, volume, diameter and surface area, as well as kinetic parameters associated with nutrient uptake (Vmax, Km, Cmin and I) were determined. Species P. notatum was the one presenting the highest root, shoot and total dry matter production, as well as the highest root volume. P. urvillei recorded the highest K content, which may be associated with thinner roots and greater root surface area. A. affinis recorded the highest Vmax value, which led to greater K uptake efficiency. RESUMO: O estudo quantificou os parâmetros cinéticos de captação de K nas gramíneas Paspalum notatum, Paspalum urvillei e Axonopus affinis associados com o crescimento. Dez mililitros (10 ml) de solução nutritiva foram coletados em vasos de dois litros - com cinco repetições em 24 horas - para determinação das concentrações de K nas amostras. A matéria seca da parte aérea e raízes; comprimento, volume, diâmetro e área superficial radicular, bem como parâmetros cinéticos associados à absorção de nutrientes (Vmax, Km, Cmin e I) foram avaliados. A espécie P. notatum apresentou a maior produção de raiz, parte aérea e MS total, bem como o maior volume de raiz. P. urvillei apresentou o maior teor de K, que pode ser associado a raízes mais finas e resultando em maior área superficial. A. affinis registrou o maior valor de Vmax, o que levou a uma maior eficiência de absorção de K.

Few options are available for controlling bermudagrass invasion of seashore paspalum. Bermudagrass and seashore paspalum tolerance to topramezone, triclopyr, or the combination of these two herbicides were evaluated in both greenhouse and field conditions. Field treatments included two sequential applications of topramezone (15.6 g ai ha−1) alone and five rates of topramezone + triclopyr (15.6 + 43.2, 15.6 + 86.3, 15.6 + 172.6, 15.6 + 345.2, or 15.6 g ai ha−1+ 690.4 g ae ha−1). Secondary greenhouse treatments included a single application of topramezone (20.8 g ha−1) or triclopyr (258.9 g ha−1) alone, or in combination at 20.8 + 258.9 or 20.8 + 517.8 g ha−1, respectively. Greenhouse and field results showed that topramezone applications in combination with triclopyr present opposite responses between bermudagrass and seashore paspalum. Topramezone increased bermudagrass injury and decreased seashore paspalum bleaching injury compared to topramezone alone. In field evaluations, topramezone + triclopyr at 15.6 + 690.4 g ha−1used in sequential applications resulted in >90% injury to bermudagrass, however, injury decreased over time. Furthermore, sequential applications of topramezone + triclopyr at 15.6 + 690.4 g ha−1resulted in >50% injury to seashore paspalum. Application programs including topramezone plus triclopyr should increase bermudagrass suppression and reduce seashore paspalum injury compared to topramezone alone. However, additional studies are needed because such practices will likely require manipulation of topramezone rate, application timing, application interval, and number of applications in order to maximize bermudagrass control and minimize seashore paspalum injury.

The presence of weeds amid pastures has caused significant damage to cattle farmers due to the difficulty in controlling these species. Paspalum virgatum stands out as an aggressive weed in Amazonian agroecosystems. Proper management of weed species is threatened by their aggressiveness, adaptation to low fertility soils and morphological, physiological and biochemical similarities with the grasses used as fodder. It is also possible that part of these characteristics of aggressiveness occur due to the ability of weeds to produce allelochemicals, resulting in damage to surrounding plants. The objective of this study was to qualitatively verify the presence of secondary metabolites in P. virgatum species under different water availability. The analyzed species were initially grown separately under three conditions of water availability: water deficit, field capacity and flooded environment. The water deficit treatment was conducted to verify weed ability to develop under conditions of extreme water shortage. This is a characteristic related to its rusticity, as found in grasses in the Amazon region. Excess water treatments were also conducted, since this is a common condition found in areas with partial flooding of a few months during the rainy season in the Amazon. After 120 days, weeds were collected and separated into roots, stems and leaves. The material was subsequently dried, ground and subjected to procedures to determine secondary metabolites. Phenolic compounds, flavonoids and alkaloids were identified in all conditions of plant development. The flavonoid detection test presented an intense yellow color. This is a strong indication of the presence of this class in stems and leaves of plants under flood and in leaves of plants under field capacity soil conditions. An intense presence of phenolic compounds was verified in stems and leaves, regardless of treatment. General alkaloids were found in great intensity in all samples. Saponins were found in leaves of P. virgatum under water stress (flooding and water deficit). All the metabolites were found in the plants, diverging between treatments and parts of the plant. It was concluded that the species presented higher steroid content in the roots when growing in places with excess of water. In conditions of full water supply, the presence of steroid was less intense in the roots, leaves and stems, result also found in roots and leaves of plants under water deficit. Alkaloids were less intensely present in the roots, regardless of the water treatment in which the plant was submitted. Results demonstrated that there are secondary metabolites responsible for some physiological ability of the weed to withstand excess or water deficit, indicating the need for further studies

Fil: Depetris, Mara Belen. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Rosario. Instituto de Investigaciones en Ciencias Agrarias de Rosario. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias. Instituto de Investigaciones en Ciencias Agrarias de Rosario; Argentina

Recent efforts placed on breeding Paspalum species made available novel genetic resources for livestock production systems. Nitrogen (N) is an important factor to increase warm‐season grass nutritive value and production, either as anthropogenic supply or in mixture with legumes. Dry matter yield (DMY) and nutritive value in Paspalum plicatulum Michx. × Paspalum guenoarum Arechav. hybrids in response to different rates of N or in mixture with temperate legumes were evaluated for two years. The experiment was a randomized complete block design in split‐plot arrangement with three replications. Treatments were six N supply systems: 0, 60, 120, 240, 480 kg N/ha and grass–legume mixture [white clover (Trifolium repens L.) + birdsfoot trefoil (Lotus corniculatus L.)] as whole plots, and six genotypes (hybrids: 1020133, 102069, 103084, 103061, P. guenoarum ecotype ‘Azulao’ and Megathyrsus maximus cv. ‘Aruana’ used as controls) as subplots. Higher N rates increased DMY and provided variability among genotypes. In general, grass–legume mixture showed greater crude protein and digestibility, and lower neutral and acid detergent fiber than N fertilized grass (p

Basic findings from classical genetic studies are available for exploiting apomixis in the breeding of several forage grass genera. Most Paspalum species are multiploid with a sexual diploid cytotype and conspecific apomictic polyploid (mainly tetraploid) cytotypes. Experimental tetraploidized diploids reproduce sexually and, when crossed with natural apomictic tetraploids, yield hybrid populations that segregate for reproductive mode. Genetic studies indicated that apomixis is inherited as a monogenic dominant factor. We recombined 50 selected sexual hybrids obtained from crosses between a tetraploidized sexual genotype of P. plicatulum and 9 natural apomictic tetraploid accessions of 6 species of the Plicatula group. A synthetic sexual tetraploid population (SSTP) of 600 individuals from mixed seed of the 50 intercrossed hybrids was space-planted in the field. Based on evaluations of plant vigor, seed set, ergot tolerance, regrowth after flowering, and cold tolerance, 31 plants were selected. Crosses between most selected plants and two testers, which belonged to P. guenoarum, were performed, and the generated progeny was planted into the field following a randomized block design with 3 replications. The progeny test was evaluated for seed fertility, biomass yield, and cold tolerance. This procedure allowed selection of 10 elite plants from the SSTP. These plants should contain genes recombined from six apomictic species, without the genetic determinants for apomixis. They may be polycrossed to generate an improved sexual population, or crossed with other apomictic genotypes to obtain improved apomictic hybrids. Fil: Novo, Patricia Elda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Acuña, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Urbani, Mario Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Galdeano, Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Espinoza, Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Quarin, Camilo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

Background: Paspalum scorbiculatum is an annual crop and has superior nutritional properties including high micronutrients, dietary fiber content and gluten free. It has low glycemic index (GI) carbohydrate diets help in prevention of Obesity, Diabeties and Cardiovascular diseases, etc. The current study was aimed to find out the suitable pre- sowing seed treatments for Kodo millet. Methods: During the Kharif season 2019- 2020 total of 12 pre- sowing seed treatments were subjected with Botanicals, Magnetic and Electric fields, Thermal (Hot water) treatments and to fix the best treatment based on Seed Quality and Morphological traits of treated seeds. Morphological traits play an major role in crop growth and development where as, the present investigation was carried out with farmer’s variety in field (RBD) design in 3 replications and laboratory (CRD) design in 4 replications in order to “Standardization of different pre- sowing seed treatments on growth, yield and yield attributing traits of Kodo millet (Paspalum scorbiculatum). Seeds were subjected to various pre- sowing seed treatments viz. (T0) control, exposure to Magnetic field at 100 mT, 200 mT, 400 mT for 15,30 and 45 min; exposure to Electric field at 50 mA, 100 mA, 150 mA for 5,10, 15 min. Treatment with botanicals cow dung (5 gm) and Datura leaf extract (2.5 ml) for 12 hrs; Thermal hot water treatment at 46°C and 50°C for 10 min. Result: Among all the treatments, T4-Magnetic field (200 mT) gave the best results in field and lab conditions of field emergence (98.610) and germination% (98.5), Magnetic field (400 mT) shown the good results and significantly higher values of all other yield (45.867, 78.833, 660.480, 165.120) and morphological traits as well as seed quality parameters like shoot length (86.925), root length (44.55), seedling length (13.131), vigour index- I and II (1267.138 and 5.058), fresh (0.343) and dry (0.0524) weight of seedlings and comparatively control (T0) was observed lowest to other treatments. As such, Magnetic treatment is quite effective for seedling establishment to overcome low germination and yield which helps in Qualitative and Quantiative seed production of Millets in sustainable agriculture.

Apomictic grasses predominate among tropical forages, and specific breeding techniques are needed for their genetic improvement. The objectives were to: 1- generate hybrids by crossing tetraploid sexual and apomictic Paspalum simplex genotypes, 2- develop a technique based on molecular markers for early identification of apomictic hybrids, and 3- determine the relationship between mode of reproduction and performance of hybrids. Crosses were made between two induced sexual and seven apomictic tetraploid plants. Identification of apomictic hybrids during seedling stage was performed using a marker linked to apomixis, and by flow cytometric seed analysis (FCSA). Hybrids were evaluated under field conditions for plant diameter and height, initial regrowth, and seasonal regrowth during two consecutive growing seasons. Sexual tetraploid plants used as female parents behaved as allogamous since 95% of the progeny had male-specific markers. The ratio between apomictic and sexual hybrids differed among crosses from 1:8.7 and 1:0.6 among crosses, with a mean of 1:2.4. There was a 96% coincidence between the use of the apomixis?linked marker and FCSA. A technique based on the use of an early DNA isolation and the amplification of a molecular marker linked to apomixis was developed. We found no overall difference between apomictic and sexual hybrids for the evaluated traits, except for fall regrowth in the first year, for which apomictic hybrids were superior. Generation of large tetraploid hybrid progenies is possible in P. simplex. Segregation for mode of reproduction depends on parents involved. Agronomic performance is not related to reproductive mode among tetraploid hybrids. Fil: Brugnoli, Elsa Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Martínez, Eric Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Ferrari Usandizaga, Silvana Consuelo. Instituto Nacional de Tecnología Agropecuaria; Argentina Fil: Zilli, Alex Leonel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Urbani, Mario Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Acuña, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina

The use of forage species adapted to the local environment allows an easier management, and greater production and stability. It also allows the conservation of the natural genetic resources, and the reduction of the costs and risks of production that further result in higher sustainability of the system. Forage quality may not be considered as important as biomass production in many forage systems. However, when forage plants constitute most or all of the ruminant diet it assumes substantially greater importance. Therefore, the goal of this study was to evaluate the crude protein (CP) content of hybrids of P. plicatulum x P. guenoarum, in a region of Southern Brazil in the Pampa biome. The hybrids evaluated were: 10202, 1020104, 102084, 102080, 1020133, 102058, 102069 (P. plicatulum “4PT” x P. guenoarum “Azulão”), 103063, 10308, 103042, 103040, 103061, 103077, 103087, 103093, 103031, 103020, 103084, and 103037 (P. plicatulum “4PT” x P. guenoarum “Baio”). The CP analyzes were performed on the leaves of the genotypes in each harvest. The hybrid 102069 “Azulão” presented the best CP content (16.4%) compared to the other genotypes in both years. These results are encouraging for forage breeding studies with species of the genus Paspalum.

Kodo millet (Paspalum scrobiculatum L.) is an important drought-tolerant crop cultivated on marginal soils under diverse environmental conditions. Its grains are nutritionally superior to those of major cereals. Knowledge of the variability in agronomic and nutritional traits is important to identify germplasm for use in crop improvement and by farmers. Two hundred kodo millet accessions were evaluated in 2 yr during the rainy season to assess variability for morphoagronomic and grain nutritional traits and to identify high grain-yielding and nutrient-rich accessions. Large variability was observed for important traits including days to maturity, grain yield, and Fe, Zn, Ca, and protein content with moderate to high heritability. Three kodo millet races did not differ significantly for grain yield or Fe, Zn, Ca, and protein content. For Zn, Fe, protein, and Ca, 78.5, 75.0, 67.5, and 54.0% of accessions, respectively, were consistent between the years, indicating the relative sensitivity of these nutrients to the environment and genotype × environment interaction. Considering data of both the years separately, 50 promising trait-specific accessions were identified, including those for early maturity (8 accessions), greater 100-seed weight (10), high grain yield (15), Fe (8), Zn (14), Ca (6) and protein content (7), and 10 with a combination of agronomic and nutritional traits. The extensive multilocation evaluation of these high-yielding, nutrient-rich accessions would be useful to identify promising genotypes for direct cultivar release or for use in crop improvement to contribute to the food and nutritional security of resource-poor farmers in a changing climate scenario.

A glasshouse study was conducted on the Louisiana State University campus in Baton Rouge, LA, to evaluate the control of brook crowngrass, rice cutgrass, southern watergrass, and water paspalum. Florpyrauxifen-benzyl was applied at 30 g ai ha−1 to each grass species at the 3- to 4-leaf or 1- to 2-stolon stage of growth. Brook crowngrass treated with florpyrauxifen was controlled 71% at 21 d after treatment. Southern watergrass and water paspalum control did not exceed 56% and 36%, respectively, across all evaluations. Rice cutgrass treated with florpyrauxifen did not reach 15% control. Plants treated with florpyrauxifen, except rice cutgrass, displayed reduction in leaf number, stolon number, plant height, and plant fresh weight. These results indicate florpyrauxifen-benzyl can help manage a brook crowngrass infestation and suppress southern watergrass. However, florpyrauxifen-benzyl has little to no activity on water paspalum and rice cutgrass, and other management options should be employed if these weeds are present.

An efficient and reproducible protocol for Agrobacterium tumefaciens mediated genetic transformation was developed for kodo millet (Paspalum scrobiculatum L.) by optimizing various parameters. Agrobacterium strains EHA 105 and LBA 4404 harboring plasmids pCNL 56 and pCAMBIA 2300, respectively, provided the highest transformation efficiency. Addition of acetosyringone (AS) in infection medium (200 µM EHA 105, 250 µM–LBA 4404) and co-cultivation medium (50 µM) increased the transformation efficiency. Transient and stable expression of gus gene was confirmed with histochemical assay of infected embryos and leaves of transformed plants, respectively. The best GUS response was obtained by pretreatment of callus with an antinecrotic mixture (10 mg/L Cys + 5 mg/L Ag + 2.5 mg/L As) at infection time of 20 min followed by co-cultivation for 3 days (EHA 105) and 5 days (LBA 4404) in dark. Regenerated transgenic plants were obtained after 8 to 10 weeks of selection on callus induction medium (NAA 0.5 mg/L, BAP 1 mg/L) containing 50 mg/L Kan + 250 mg/L Cef and were rooted for 2 weeks on MS medium containing PAA (1 mg/L) and phytagel. The plantlets established in greenhouse showed normal growth. Therefore, the protocol developed in the present study can be used for development of improved varieties of kodo millet.

The continuing decline in global drinking water reserves necessitates finding alternative water sources for turfgrass irrigation, especially in southern semi-arid Mediterranean countries. The aim of the present study was to evaluate the potential of using seawater for irrigating two varieties of seashore paspalum (Paspalum vaginatum Sw.), &ldquo, Marina&rdquo, and &ldquo, Platinum &Tau, &Epsilon, &rdquo, growing in shallow green roof substrates, and to determine their recuperative capacity after the termination of the salt stress period. The greenhouse study comprised of 48 lysimeters equipped with extensive green roof layering. Treatments included: (i) two substrate depths (7.5 cm or 15 cm) and (ii) three seawater irrigation regimes (7 mm, 15 mm, or 45 mm every two days). Measurements included the determination of green turf cover (GTC) as well as the leaching fraction (LF) and leachate electrical conductivity (ECL) draining from the lysimeters. It was found that during the 46-d salt stress period, none of the seawater irrigation regimes managed to maintain acceptable GTC levels for both seashore paspalum varieties. Increasing the green roof substrate depth from 7.5 cm to 15 cm resulted in GTC improvement. During the recovery period, the use of potable water as irrigation source improved GTC levels. After 40 d the recovery was complete since GTC exceeded 90% in all treatments for both varieties. Regression curves correlating GTC response to ECL can be used to estimate the leaching requirements of turfgrasses grown in shallow green roof systems when irrigated with saline water.

Of the natural pastures grown in southern Brazil, those of the genus Paspalum are the most important. One of the factors that hinder their cultivation is the availability of quality seeds, that are often compromised by the presence of fungi. This study determined the in vitro sensitivity of Paspalum guenoarum ecotype azulão seed-associated fungus to certain fungicides and to measure the efficiency of chemical treatments for fungal control and seed physiological performance. Bipolaris micropus, Epicoccum sorghinum, Curvularia geniculata and Fusarium incarnatum associated with seeds were tested in vitro against Carbendazim; Tiram, Fludioxonil; Metalaxil-M, Carboxina; Tiram and Tiofanato-metílico at 0, 1, 2.5, 5, 10 and 30 µg/mL. This experiment was conducted in a completely randomized design (factorial 4 × 4 × 6). Qualitative variables were compared using the Tukey test (P ≤ 0.05) and quantitative variables were subjected to regression analysis. Carbendazim; Tiram and Fludioxonil; Metalaxil-M had the best fungicidal performances, each inhibiting three of the four fungi with LD50s below 1 µg/mL. Subsequently, these two fungicides were used alone or in combination in the in vivo test. A completely randomized design was used and the means were compared using the Tukey test (P < 0.05). The chemical treatment of the seeds resulted in improvement of five of the six evaluated physiological parameters. The identification of the primary fungi associated with Paspalum seeds reported in this research, as well as damage done to them, can be diminished using appropriate measures such as seed treatments. RESUMO: Das pastagens naturais cultivadas no sul do Brasil, as do gênero Paspalum são as mais importantes. Um dos fatores que dificultam o cultivo é a disponibilidade de sementes de qualidade, muitas vezes comprometidas pela presença de fungos. Os objetivos deste estudo foram determinar a sensibilidade in vitro de fungos associados a sementes de Paspalum guenoarum ecótipo azulão a determinados fungicidas, medir a eficiência de tratamentos químicos para controle desses fungos e o desempenho fisiológico das sementes. Os fungos associados às sementes, Bipolaris micropus, Epicoccum sorghinum, Curvularia geniculata e Fusarium incarnatum foram testados in vitro contra Carbendazim; Tiram, Fludioxonil; Metalaxil-M, Carboxina; Tiram e Tiofanato-metílico em 0, 1, 2,5, 5, 10 e 30 µg/mL. Este experimento foi conduzido em um delineamento inteiramente casualizado (fatorial 4 × 4 × 6). As variáveis qualitativas foram comparadas pelo teste de Tukey (P ≤ 0,05) e as variáveis quantitativas foram submetidas à análise de regressão. Carbendazim; Tiram e Fludioxonil; Metalaxil-M tiveram os melhores desempenhos fungicidas, cada um inibindo três dos quatro fungos com LD50 abaixo de 1 µg/mL. Posteriormente, esses dois fungicidas foram utilizados isoladamente ou em combinação no teste in vivo. O delineamento experimental foi inteiramente casualizado e as médias comparadas pelo teste de Tukey (P < 0,05). O tratamento químico das sementes resultou na melhoria de cinco dos seis parâmetros fisiológicos avaliados. A identificação dos fungos primários associados às sementes de Paspalum relatadas neste trabalho, bem como os danos causados por eles, podem ser diminuídos usando medidas apropriadas, como tratamento de sementes.

Made available in DSpace on 2021-06-25T11:21:34Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01. Added 1 bitstream(s) on 2021-07-15T14:36:12Z : No. of bitstreams: 1 S0100-83582020000100309.pdf: 355489 bytes, checksum: ad099a4eddef1be6ad92de5581d29c47 (MD5) Sumitomo Chemical Brasil Industria Quimica S.A. Background: Talquezal (Paspalum virgatum L.) has become one of the main pasture weeds due to its association with the Urochloa brizantha death syndrome, a disease that causes the progressive death of clumps of susceptible grasses in patches, which leads to weed colonization and pasture degradation. Understanding the weed emergence pattern is essential in decision making for management strategies. Objective: Thus, this study aimed to evaluate the emergence pattern of talquezal seedlings according to its origin and the amount of straw covering the soil. Methods: The experiment was carried out in a greenhouse in a completely randomized design, with six replications and treatments arranged in an 8 x 3 factorial scheme with eight amounts of Urochloa brizantha straw covering the seeds (0, 0.5, 1.0, 2.0, 4.0, 6.0, 8.0, and 10.0 ton ha(-1)) and three collection sites (Rondonopolis, Redencao, and Cacoal). The effect of the origin and amount of straw was evaluated by the percentage of emergence, relative emergence frequency, mean emergence time, emergence synchrony, and emergence speed index of seedlings obtained over 35 days after sowing. Results: Talquezal seeds showed high seedling emergence vigor regardless of their origin under amounts of straw lower than 4.0 ton ha(-1) Conclusions: The result suggests that the amounts of U. brizantha straw higher than 4.0 ton ha(-1) on the soil surface, the lower is the percentage of Talquezal seedling emergence. Univ Fed Mato Grosso, Campus Univ Araguaia, Barra Do Garcas, MT, Brazil Univ Estadual Paulista Julio de Mesquite Filho, Fac Ciencias Agr & Vet, Campus Jaboticabal, Jaboticabal, SP, Brazil Univ Estadual Paulista Julio de Mesquite Filho, Fac Ciencias Agr & Vet, Campus Jaboticabal, Jaboticabal, SP, Brazil

Background: Kodo millet is an important drought tolerant crop and has high nutritional values, dietary fiber and antioxidant properties. It has considerable production potential in marginal and low fertility soils under diverse environmental conditions. Considering the importance of the crop, it is necessary to improve the nutritional quality along with grain yield of the crop. With this background, the investigation was aimed to study the correlation and path coefficient analysis which helps to identify the promising traits for yield and quality improvement. Methods: One hundred and three kodo millet germplasm lines were evaluated for 13 morpho-agronomic and two grain nutritional traits. The crop was raised in randomized block design to select the promising genotypes and to study the association among the traits and the magnitude of direct and indirect effects for fifteen quantitative traits. Result: Based on the overall mean performance the significant genotypes were identified and found wide range of variability for different traits. Character association studies indicated that days to first flowering, days to 50 per cent flowering, plant height, number of productive tillers, peduncle length, inflorescence length, length of the longest raceme and thumb length were significantly positive association with grain yield per plant. Path coefficient analysis revealed that inflorescence length, plant height, length of the longest raceme, flag leaf blade length and number of productive tillers exhibited high direct positive effect on grain yield. Therefore, giving importance of these traits during selections may be useful for developing nutritionally superior high yielding kodo millet genotypes.

In the arid regions, turfgrass cover is an integral part of landscape to protect the soil from erosion, enhance the aesthetic value, and improve the microclimate. The salinity and the scarcity of f...

Paspalum commersonii (Poaceae) is a herbaceous perennial weed distributed in the tropics and subtropics regions and grows mainly in the moist, or even flooded soil. It often appears in the rice field as a competitive weed and difficult to manage. Its strong competitive nature indicates possible allelopathic potential of P. commersonii. However, no studies have been found yet on the allelopathic activity of P. commersonii. Thus, we investigated the allelopathic potential of this weed and determined its allelopathic substances. Aqueous methanol extracts of P. commersonii showed concentration-dependent inhibitory activity on the seedling growth of cress, alfalfa, rapeseed, lettuce, barnyard grass, foxtail fescue, Italian ryegrass, and timothy. Two substances were isolated through bioassay-guided fractionation and their structures were determined through spectral data as dehydrovomifoliol and loliolide. Dehydrovomifoliol and loliolide started inhibiting the shoot and root growth of cress at concentrat...

Turfgrass cover is an inevitable component in the urban landscapes of the United Arab Emirates. Tolerance to abiotic stress like salt, drought, and high temperature is a potential factor to be considered in the selection of turfgrass for the landscapes in the arid regions. Three Seashore paspalum genotypes, four Bermudagrass cultivars along with tall fescue as a control were screened for enzymatic changes under four different saline irrigation levels of 5,000, 10,000, 15,000, and 20,000 mg L−1 of salinity. Irrigation with potable water served as the control. Turfgrasses were maintained in a field experiment under factorial randomized block design for a period of two years under sustained saline conditions by working out the leaching fraction to maintain the precise level of salinity in each treatment throughout the experimental period. The activities of antioxidant enzymes such as superoxide dismutase (SOD), ascorbate peroxidase (APX), peroxidase (POD), polyphenol oxidase (PPO), and catalase (CAT)...

The evaluation of genetic resources in germplasm banks of Paspalum can contribute to their use in breeding programs and for advanced research in biotechnology. This study evaluated the tolerance of 11 Paspalum accessions to abiotic stress caused by soil water deficit in a greenhouse experiment at Embrapa Pecuária Sudeste, São Carlos, state of São Paulo, Brazil. The variables analyzed were: dry biomass of green matter, dead matter and roots; leaf area; leaf water potential; number of days to lose leaf turgor (wilting); soil moisture at wilting; and number of tillers per pot. The results showed high genetic variability for all traits, not only among species but also within species, and also reflected the existence of different strategies of response and potential adaptation to water deficit events. For breeding programs, when the aim is to produce materials better adapted to the occurrence of prolonged drought, 5 accessions from this group seem to have good potential: P. malacophyllum BGP 289, P. quarinii BGP 229, P. regnellii BGP 112, P. conspersum BGP 402 and P. urvillei x P. dilatatum BGP 238. Conversely, when the goal is to select materials for short-term water stress conditions, 6 accessions stand out: P. atratum BGP 308, P. regnellii BGP 215, 248 and 397, P. dilatatum BGP 234 and P. malacophyllum BGP 293. Resumen La evaluación de recursos genéticos en bancos de germoplasma de Paspalum constituye una gran ayuda en programas de mejoramiento genético y de investigación avanzada en biotecnología. En un experimento en macetas en Embrapa Pecuária Sudeste, São Carlos, estado de São Paulo, Brasil, se evaluó la tolerancia de 11 accesiones de varias especies de Paspalum al estrés abiótico causado por el déficit hídrico en el suelo. Las variables analizadas fueron: biomasa seca de la materia verde, materia muerta y raíces; área foliar; potencial hídrico foliar; número de días hasta la pérdida de la turgencia foliar (marchitamiento); humedad del suelo al momento del marchitamiento de las plantas; y número de brotes por planta. Los resultados mostraron tanto una alta variabilidad genética para todos los parámetros, no solo entre las especies, sino también dentro de las especies, como la existencia de diferentes estrategias de respuesta y potencial adaptación a eventos de déficit hídrico. Para los programas de fitomejoramiento, cuando el objetivo es producir materiales mejor adaptados a la sequía prolongada, las accesiones con mayor potencial fueron: P. malacophyllum BGP 289, P. quarinii BGP 229, P. regnellii BGP 112, P. conspersum BGP 402 y P. urvillei xP. dilatatum BGP 238. Por el contrario, cuando el objetivo es seleccionar materiales para condiciones de estrés hídrico de corta duración, se destacan las accesiones: P. atratum BGP 308, P. regnellii BGP 215, 248 y 397, P. dilatatum BGP 234 y P. malacophyllum BGP 293.

The experimental material comprised of one hundred and three germplasm accessions of kodo millet (Paspalum scrobiculatum L.) were evaluated to assess the genetic variability, heritability and genetic advance for fifteen yield component traits. Analysis of variance revealed that there were significant differences among the accessions for all the traits studied. The coefficient of variation at phenotypic (PCV) and genotypic (GCV) levels were high for Zn content, grain yield per plant, Fe content, number of productive tillers and thumb length. Broad sense heritability ranged from 54.18 per cent for length of the longest raceme to 97.30 per cent for days to 50 per cent flowering. High heritability coupled with high genetic advance as per cent of mean was observed for plant height, number of basal tillers, number of productive tillers, flag leaf width, inflorescence length, thumb length, Zn content, Fe content and grain yield per plant which indicates that these traits are under the influence of additive gene effects and selection may be effective for these characters.

Limited knowledge about the agronomic potential of Paspalum species from the Americas hinders their use in pastures. The response mechanisms to water deficit and waterlogging were studied in five accessions of Paspalum sp. (P. regnellii cv. BRS Guara and BGP 397, P. conspersum BGP 402 and P. malacophyllum BGP 289 and BGP 293) and Urochloa brizantha cv. Marandu. Morphological and physiological traits at the end of the stress and after the recovery period were measured. All Paspalum accessions, especially BGP 289, BGP 402 and BGP 397, and also cv. Marandu, showed survival mechanisms to water deficit. BRS Guara showed adaptive features to waterlogging, although had with a low survival rate to water deficit. Under waterlogging, BGP 289 and cv. Marandu showed reduced growth, and after the recovery period, they presented low plant survival and root recovery. Although growth of BGP 293 was reduced during waterlogging, it presented high tiller survival rate. BGP 293, BGP 402 and BGP 397 showed adaptive potential strategies for waterlogging and water deficit. There is genetic variability among the evaluated accessions for water deficit and waterlogging stresses, suggesting that they may be used per se or as progenitors in crosses with other genotypes in breeding programmes.

The development of a turf-type bahiagrass could have a remarkable impact on the billion-dollar turf industry in the south-eastern United States. The goals of this study were to (i) select bahiagrass genotypes with improved turf attributes and (ii) determine the reproductive mode and seed fertility of selected genotypes. The population included mutants, wild types, hybrids and standard cultivars evaluated at two locations for two years. Morphological variation was observed and clonal repeatability (H2) ranged from 0.27 to 0.90. Flowering was extremely reduced in some mutants, which also exhibited dark green colour, finer texture and reduced canopy height. Cytoembryological observations revealed that diploids reproduced sexually and tetraploids by obligate or facultative apomixis. Genotypes with superior seed fertility were identified, while others were comparable to the standard cultivars. While mutant plants exhibited great morphological variation, the random mutations did not affect their reproductive mode, validating the use of mutagenesis in apomictic species. The high H2 indicated that selection for improved turf attributes could be successfully performed with the advantage of clonal seed propagation.

Two varieties of bahiagrass were evaluated under Florida conditions for forage tolerance to the new herbicide, aminocyclopyrachlor (ACP), which is essential for product development decisions. Herbicide treatments included ACP alone at 70 and 140 g ai ha−1, ACP + chlorsulfuron at 69 + 27 and 138 + 54 g ai ha−1, ACP + 2,4-D amine at 70 + 532 g ai ha−1 and 140 + 1,064 g ai ha−1, ACP + triclopyr-amine at 70 + 140 g ai ha−1 and 140 + 280 g ai ha−1, and ACP + metsulfuron at 46 + 7, 78 + 12, and 168 + 26 g ai ha−1, and also included a nontreated check. ‘Argentine’ bahiagrass was the most tolerant forage species, and ‘Pensacola’ bahiagrass was sensitive to ACP + metsulfuron and initially to ACP + chlorsulfuron. Herbicide applications using ACP, when labeled, will likely provide good to excellent control of several weed species, with little long-term impact on bahiagrass forage production when the cultivar is known.

Gaeumannomyces graminis var. graminis is an ectotrophic, root-infecting fungus found on some warm-season turfgrass species (1). A sample of seashore paspalum (Paspalum vaginatum) exhibiting rotted roots and stolons was taken from dying patches of turf in a home lawn in Hernando County, FL, and submitted to the Florida Extension Plant Disease Clinic, Gainesville, in October 2001. The lawn had been established within the previous year. Strongly lobed hyphopodia typical of G. graminis var. graminis (3,4) were present on diseased roots and stolons, and no other fungal plant pathogens were detected in the sample. Diseased roots and stolons with lobed hyphopodia were surface-sterilized and placed on one-quarter-strength potato dextrose agar (PDA) amended with rifampicin and streptomycin. One isolate produced structures characteristic of G. graminis var. graminis (3,4), including dark, strongly lobed hyphopodia, and perithecia and ascospores in PDA after incubation. The isolate (PDC 2965) was grown on a sterile ryegrass seed substrate at 25°C for 4 weeks to produce inoculum (2). The isolate was used to inoculate pots of ‘Sea Isle 1’ seashore paspalum grown in sterile soil from sprigs. An inoculum layer, 1 to 2 cm deep, was placed 2 to 4 cm below each sprig and covered with an overlay of sterile soil prior to sprigging (2). Following 4 weeks of plant growth in a greenhouse, dark, necrotic lesions appeared on leaf bases. Very dark lesions developed on roots, and brown runner hyphae and strongly lobed hyphopodia were observed on root and shoot tissues. Selected pieces of symptomatic root and shoot tissue were surface-sterilized and placed on PDA. One week later, dark mycelia and deeply lobed hyphopodia were observed growing from roots and shoots on the PDA. After 1 month, black, flask-shaped perithecia, 156 to 234 μm in body width, developed in cultures. Hyaline, filiform, septate ascospores ranged from 75 to 100 μm (mean = 89 μm; n = 250) long and were approximately 2.5 μm wide. Hyphopodia, perithecia, and ascospores were characteristic of G. graminis var. graminis (3,4). To our knowledge, this is the first report of take-all root rot disease due to G. graminis var. graminis on seashore paspalum in the United States. References: (1) L. E. Datnoff et al. Plant Dis. 81:1127, 1997. (2) M. L. Elliott. Plant Dis. 79:699, 1995. (3) M. L. Elliott and P. J. Landschoot. Plant Dis. 75:238, 1991. (4) P. J. Landschoot. Taxonomy and biology of ectotrophic root-infecting fungi associated with patch diseases of turfgrasses. Pages 41–71 in: Turfgrass Patch Diseases. B. B. Clarke and A. B. Gould, eds. American Phytopathological Society, St. Paul, MN, 1997.

Seashore paspalum (Paspalum vaginatum Swartz) is a warm-season grass capable of growing in the saline environments present in coastal areas of Florida (2). A major limitation of cultivating turfgrasses in the sandy soils of Florida is the destruction of roots by plant-parasitic nematodes (3). A survey was performed to determine the plant-parasitic nematodes associated with seashore paspalum. Sampling locations ranged from Daytona Beach to Miami Beach on the eastern coast and from Tampa to Naples on the western coast. Soil samples were taken during the spring and summer months of 2002 and 2003 from different golf courses and home lawns. In 2002, soil samples were taken from five golf courses (37 samples) and seven home lawns (17 samples). In the next year, three golf courses (23 samples) and 13 home lawns (34 samples) were sampled. Nematodes were extracted from 100 cm3 soil samples using a modified centrifugal-sugar flotation technique (1). Ten genera of plant-parasitic nematodes were present from the samples obtained from golf courses. In addition, two more plant-parasitic nematode genera were present in samples from home lawns. The genera most frequently detected were Hoplolaimus, Mesocriconema, Hemicriconemoides, and Helicotylenchus, which were found at 100, 100, 88, and 88% of the golf courses surveyed and at 75, 95, 70, and 85% of the home lawns sampled, respectively. Genera Xiphinema, Pratylenchus, and Tylenchorhynchus, were found in less than 30% of the golf courses and less than 45% of the home lawns sampled. Genera Peltamigratus and Hemicycliophora were associated with a low percentage of the home lawns. A moderately high frequency of the genus Belonolaimus present in soil samples from golf courses (50%) and home lawns (40%) was consistent for other grasses grown in sandy soils associated with coastal areas in Florida (4). Populations of the genera Belonolaimus, Hoplolaimus, Helicotylenchus, Trichodorus, Hemicriconemoides, and Mesocriconema were above the action threshold levels for bermudagrass used by the University of Florida Nematode Assay Laboratory. Genera Hoplolaimus, Belonolaimus, and Trichodorus were associated with irregular-shaped yellowing and declining turfgrass areas sampled in this survey. Large populations of Helicotylenchus spp. (>500 nematodes per 100 cm3 of soil) were often found associated with seashore paspalum. To our knowledge, this is the first report of plant-parasitic nematodes associated with seashore paspalum in Florida. References: (1) W. R. Jenkins. Plant Dis. Rep. 48:692, 1964. (2) J. Morton. Proc. Fla. State Hortic. Soc. 86:482, 1973. (3) V. G. Perry and H. Rhoades. Pages 144–149 in: Nematology in the Southern Region of the United States. Southern Cooperative Series Bull. 276, University of Arkansas Agric. Pub., Fayetteville, 1982. (4) R. T. Robbins and K. R. Barker. J. Nematol. 6:1, 1974.

Seashore paspalum (Paspalum vaginatum Sw.) is a newly cultivated C4 turfgrass that has exceptional salinity tolerance and is highly suited for use on golf courses in coastal areas. In October 2008 and June 2009, circular patches of blighted seashore paspalum ranging from 30 cm to >3 m in diameter were observed in fairways, tees, and roughs established with ‘Supreme’ seashore paspalum at Roco Ki Golf Club in Macao, Dominican Republic. Affected patches were initially chlorotic followed by reddish brown necrosis of leaves and leaf sheaths. Reddish brown-to-gray lesions were also observed on leaf sheaths during the early stages of necrosis. During periods of wet or humid weather from June through October, basidiocarps were produced on necrotic plant tissue and identified as Marasmiellus mesosporus Singer (2). Three isolates were obtained by plating symptomatic leaf sheaths that were surface sterilized with a 0.5% NaOCl solution on potato dextrose agar amended with 50 ppm each of streptomycin, chloramphenicol, and tetracycline (PDA+++). Sequences of the internal transcribed spacer (ITS) region of rDNA, obtained from these three isolates and three stipes of basidiocarps, were identical to each other and 99% similar to a M. mesosporus sequence deposited in the NCBI database (Accession No. AB517375). To confirm pathogenicity, a M. mesosporus isolate obtained from symptomatic plant tissue was inoculated onto 6-week-old P. vaginatum (‘Seaspray’) planted (0.5 mg seed/cm2) in 10-cm-diameter pots containing a mixture of 80% sand and 20% reed sedge peat. Two weeks prior to inoculation, the isolate was grown on a sterilized mixture of 100 cm3 of rye grain, 4.9 ml of CaCO3, and 100 ml of water. Infested grains were placed 0.5 cm below the soil surface for inoculation. Pots were inoculated with five infested grains or five sterilized, uninfested grains with three replications of each treatment. After inoculation, pots were placed in a growth chamber with a 12-h photoperiod set to 30°C during the day and 26°C at night. Approximately 20% of plants in inoculated pots were necrotic 7 days postinoculation and this increased to 75% by 21 days postinoculation. Diseased plants in inoculated pots exhibited symptoms similar to those observed in the field. Leaves were initially chlorotic with brown lesions on lower leaf sheaths and eventually turned necrotic, reddish brown, and collapsed. Pots receiving uninfested grains were healthy and showed no symptoms on all rating dates. At 21 days postinoculation, basidiocarps were observed emerging from three colonized plants at the base of the oldest leaf sheath near the crown. Three reisolations were made on PDA+++ from stem lesions surface sterilized with a 0.5% NaOCl solution. All reisolations were confirmed as M. mesosporus by culture morphology and ITS sequence data. M. mesosporus was previously reported causing disease on American beachgrass (Ammophila breviligulata Fernald) in North Carolina (1) and recently in Japan (3). The pathogen was initially placed in the genus Marasmius and reported as the cause of the disease Marasmius blight (1). Subsequent morphological observation found that the pathogen belonged in the genus Marasmiellus (2). To our knowledge, this is the first report of M. mesosporus causing Marasmiellus blight on seashore paspalum, a high-amenity turfgrass. References: (1) L. Lucas et al. Plant Dis. Rep. 55:582, 1971. (2) R. Singer et al. Mycologia 65:468, 1973. (3) S. Takehashi et al. Mycoscience 48:407, 2007.

Seashore paspalum (Paspalum vaginatum Swartz) is a warm-season perennial turfgrass commonly used for golf courses that are grown in saline environments or using saline water for irrigation. However, seashore paspalum is also grown in non-saline conditions due to its low fertilizer and water requirements (2). In Barbados, on a newly constructed golf course, seashore paspalum ‘Sea Isle Supreme’ sprigs were imported from Georgia (United States) and were planted over 2006 and 2007 on greens, tees, fairways, and rough. Golf greens were constructed following the United States Golf Association Green Section (Far Hills, NJ) putting green guidelines. Tees and fairways were constructed using native soil. Two years after the grow-in, the putting greens began to exhibit irregular chlorotic patches, followed by gradual thinning and decline of turfgrass stand density in those areas. Additionally, turfgrass roots sampled from those symptomatic patches appeared to be abbreviated compared to non-symptomatic areas of the greens. A survey was conducted in May 2013 to determine if plant-parasitic nematodes were present coinciding with the observed symptoms, which were similar to those described in a previous report (3). Consequently, two samples were collected from each green with a total of four greens sampled. Each sample consisted of 20 soil cores (15 cm depth × 1.2 cm in diameter) from either areas of the greens showing symptoms or from non-symptomatic areas. Nematodes were extracted from 100 cm3 soil samples using a modified centrifugal-sugar flotation technique (4). No plant parasitic nematodes were present in any of the samples from the non-symptomatic areas. Three genera of plant parasitic nematodes were found in all the samples from the symptomatic areas: Helicotylenchus. Mesocriconema, and Pratylenchus. Nematode populations of these genera averaged 30, 60, and 200 nematodes per 100 cm3, respectively. Populations of the genera Helicotylenchus and Mesocriconema were below the action threshold levels for seashore paspalum used by the University of Florida Nematode Assay Laboratory (1). Currently, no threshold exists for Pratylenchus for seashore paspalum. Conversely, the genera Helicotylenchus. Mesocriconema, and Pratylenchus were found associated with the irregular chlorotic patches but not with the non-symptomatic areas. To our knowledge, this is the first report of plant parasitic nematodes associated with seashore paspalum maintained as putting greens in Barbados. References: (1) W. T. Crow. Nematode management for golf courses in Florida. EDIS. Accessed 31 July 2013 from: http://edis.ifas.ufl.edu/in124 , 2001. (2) R. R. Duncan and R. N. Carrow. Seashore Paspalum: The Environmental Turfgrass. John Wiley & Sons, Inc., Hoboken, New Jersey, 2000. (3) A. C. Hixson and W. T. Crow. Plant Dis. 88:680, 2004. (4) W. R. Jenkins. Plant Dis. Rep. 48:692, 1964.

Core Ideas Developed genome‐wide SNP marker data for kodo, proso, and little millet Marker data used to analyze genetic diversity Heritability results of various traits used to validate genetic data Millets are a diverse group of small‐seeded grains that are rich in nutrients but have received relatively little advanced plant breeding research. Millets are important to smallholder farmers in Africa and Asia because of their short growing season, good stress tolerance, and high nutritional content. To advance the study and use of these species, we present genome‐wide marker datasets and population structure analyses for three minor millets: kodo millet (Paspalum scrobiculatum L.), little millet (Panicum sumatrense Roth), and proso millet (Panicum miliaceum L.).We generated genome‐wide marker data sets for 190 accessions of each species with genotyping‐by‐sequencing (GBS). After filtering, we retained between 161 and 165 accessions of each species, with 3461, 2245, and 1882 single‐nucleotide polymorphisms (SNPs) for kodo, little, and proso millet, respectively. Population genetic analysis revealed seven putative subpopulations of kodo millet and eight each of proso millet and little millet. To confirm the accuracy of this genetic data, we used public phenotype data on a subset of these accessions to estimate the heritability of various agronomically relevant phenotypes. Heritability values largely agree with the prior expectation for each phenotype, indicating that these SNPs provide an accurate genome‐wide sample of genetic variation. These data represent one of first genome‐wide population genetics analyses—and the most extensive—in these species and the first genomic analyses of any sort for little millet and kodo millet. These data will be a valuable resource for researchers and breeders trying to improve these crops for smallholder farmers.

Seashore paspalum (Paspalum vaginatum Swartz) is an important warm-season turfgrass indigenous to tropical and coastal areas worldwide. The objectives of this study were to investigate the growth response and ion regulation of Chinese seashore paspalum germplasm under salinity stress. Twenty-seven seashore paspalum accessions and one check cultivar “Sea Isle 2000” were grown in solution culture in a glasshouse, with NaCl added to achieve salinities of 0 (control), 340 and 510 mmol/L. Compared with the nonsaline controls, the salinity stressed accessions showed significantly increased leaf firing, decreased shoot growth, and an increase or decrease in root growth. Significant genetic variations in the leaf firing (LF), relative shoot weight (RSW) and relative root weight (RRW) were found among the different accessions, with coefficients of variation ranging from 19.54% to 37.84%. The P40 accession had the best salinity tolerance with little leaf firing under salinity stress, followed by Sea Isle 2000, P29 and P14. For the control, the average K+ concentration was 1161.69 mmol/kg in the shoots and 383.73 mmol/kg in the roots. Compared to the control, the salinity treatment showed that the K+ concentration treatment decreased in both the shoots and roots; however, the percentage of the reduction in the shoots was significantly lower (26.20%) than that in the roots (69.68%). The Na+ concentration was very low in both the shoots and roots of the seashore paspalum, with an average of 65.90 mmol/kg and 39.50 mmol/kg, respectively, under the treatment of nonsalinity. Compared to the nonsalinity control, the Na+ concentration greatly increased in both the shoots and roots; however, the percentage of the increase in the shoots was lower (15-fold) than in the roots (25-fold). The results indicate that taking up more of the K+, maintaining a high K+ concentration in the shoots and reducing the Na+ being transferred from the roots to the shoots could be the mechanisms for Na+ and K+ regulation for salinity tolerance in seashore paspalum.

‘Boyero UNNE’ (Reg. No. CV-5, PI 676021) bahiagrass (Paspalum notatum Flüggé) was registered with the National Register of Plant Cultivars and the National Register of Property for Plant Cultivars, Ministry of Agriculture, Livestock Exploitations, and Fisheries of Argentina, Resolution no. 276 in August 2012 (Reg. No. 3213) and released by the National University of the Northeast (UNNE), Faculty of Agricultural Sciences (FCA), Corrientes, Argentina. Boyero UNNE is a tetraploid, highly apomictic F1 hybrid developed between an experimentally obtained female parent, reproducing sexually, and an apomictic, wild bahiagrass genotype. It is the first registered cultivar of a tetraploid apomictic P. notatum developed by breeding through a sexual × apomictic hybridization scheme, exploiting apomixis and plant selection in the F1 progeny. The new cultivar has a more upright growing habit than tetraploid bahiagrass cultivars currently in use or wild tetraploid biotypes. It can produce approximately 19% more forage dry matter than its apomictic male parent, largely exceeding (20–51%) the wild bahiagrass type currently found in natural pasturelands of northeastern Argentina, and it produced 4 to 26% more than the cultivar Argentine at three locations in Florida, USA. Fil: Urbani, Mario Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Acuña, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Doval, D. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Sartor, Maria Esperanza. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste. Instituto de Botánica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botánica del Nordeste; Argentina Fil: Galdeano, Florencia. Universidad Nacional del Nordeste; Argentina Fil: Blount, A. R.. North Florida Research And Education Center; Fil: Quesenberry, K. H.. University of Florida; Estados Unidos Fil: Mackowiak, Chery L.. North Florida Research And Education Center; Fil: Quarin, Camilo Luis. Universidad Nacional del Nordeste; Argentina

The objective of this experiment was to evaluate the Fieldscout CM 1000 NDVI and Yara N-Tester as easy-to-use and cost-effective tools for predicting foliar chlorophylls (a, b and total) and crude protein (CP) concentrations in herbage from three tropical grass species. Optical chlorophyll measurements were taken at three stages (4, 8 and 12 weeks) of regrowth maturity in Guinea grass (Panicum maximum) and Mulato II (Brachiaria hybrid) and at 6 and 12 weeks maturity in Paspalum spp (Paspalum atratum). Grass samples were harvested subsequent to optical measurements for laboratory analysis to determine CP and solvent-extractable chlorophylls (a, b and total) concentrations. Optical chlorophyll measurements and CP concentrations were highly correlated (Yara N-Tester: r2 = 0·77–0·89; Fieldscout CM 1000 NDVI: r2 = 0·52–0·84). Crude protein prediction models from the Yara N-Tester and Fieldscout CM 1000 NDVI accounted for 70–89% and 44–73% CP variability, respectively, in Mulato II and Guinea grass. The Yara N-tester produced more accurate and reliable CP estimates based on very high concordance correlation coefficient [CCC (0·73–0·91)] and low rMSPE, mean and regression bias. It is concluded that the Yara N-Tester produces more accurate and reliable CP estimates of tropical pastures.

Osmotic stresses caused by reduced water availability or the accumulation of salts in the soil can be highly damaging to plants. The objective of this study was to investigate physiological responses and tolerance mechanisms of two turfgrass species (seashore paspalum and centipedegrass) with distinct differences in salinity tolerance exposed to osmotic and iso-osmotic salt stresses. Three turfgrass genotypes including seashore paspalums ‘Seastar’ and ‘UGP113’, and centipedegrass ‘TifBlair’ were grown in ½ strength Hoagland’s solution with three different treatment conditions; control (no external addition), salt stress (-0.4 MPa by adding NaCl) and osmotic stress [-0.4 MPa by adding polyethylene glycol (PEG)]. Osmotic stress damages were more severe with greater reductions in turf quality, photochemical efficiency (Fv/Fm), relative water content (RWC) and leaf water potential (Ψw) compared to iso-osmotic salt stress in both seashore paspalum and centipedegrass. Greater osmotic adjustment (OA) with greater accumulation of metabolically inexpensive inorganic osmolytes (Na+) helped turfgrasses to lessen damages in salt stress compared to osmotic stress. However, such accumulation of Na+ resulted ion-toxicity and triggered some damages in terms of increased electrolyte leakage (EL) and reduced total protein in salt-sensitive centipedegrass. Seashore paspalum had better ion regulation and also maintained greater antioxidant enzyme activities compared to centipedegrass; therefore it was able to avoid ion-specific damages under salt stress. Differences in the utilization of specific solutes for osmotic adjustment and antioxidant metabolism are partially responsible for the differences in salt versus osmotic stress responses in these species; the regulation of these defense mechanisms requires further investigation.

This work was conducted in the Centro de Pesquisa, Pós-graduação e Preservação Amazônica (CIPCA), located in the Ecuadorian Amazon Region, with the goal to analyze the presence of weeds in promising clones of cocoa. The EET-95, EET-96 and EET-103 promising clones were evaluated, and the control sample was CCN-51. To do so, the relative frequency and distribution of the existing weeds were determined, as well as their biomass, which was statistically analyzed by the ANOVA of a factor and the HSD Tukey’s test. The presence of weeds was influenced by the studied genotypes, due to the fact that promising clones were associated to high frequency and distribution, such as Cyperus odoratus, Megathyrsus maximus, Sauvagesia erecta ssp. erecta. Other species appeared to be associated more to the CCN-51 clone, such as Scleria pterota, Paspalum conjugatuns and Rottboellia cochinchinensis. Higher weed biomass was verified in clone CCN-51. RESUMO: O presente trabalho foi realizado no Centro de Pesquisa, Pós-graduação e Preservação Amazônica (CIPCA), localizado na Região Amazônica Equatoriana, com o objetivo de analisar a presença de plantas invasoras em clones promissores de cacau. Foram avaliados os clones promissores EET-95, EET-96 e EET-103 e se utilizou como controle o CCN-51. Para isso, foi determinada a frequência e a distribuição relativa de plantas daninhas presentes, assim como a biomassa destas, que foi analisada estatisticamente por meio da ANOVA de um fator e o teste HSD de Tukey. A presença de plantas daninhas foi influenciada pelos genótipos estudados, devido ao fato de que os clones promissores estavam associados com a alta frequência e a distribuição, como o Cyperus odoratus, Megathyrsus maximus, Sauvagesia erecta ssp. erecta. Outras espécies mostraram estar associadas em maior medida ao clone CCN-51, como Scleria pterota, Paspalum conjugatuns e Rottboellia cochinchinensis. A maior biomassa de plantas daninhas foi verificada no clone CCN-51.

Paspalum notatum is a polymorphic species with two accepted varieties, according to the ploidy level. The ploidy level is closely related to the reproductive mode of this species. Usually, diploid cytotypes have sexual reproduction, and tetraploid cytotypes have an apomictic reproduction. Apomixis limits genetic recombination, hindering the development of new cultivars. The identification of sexual plants represents many possibilities in breeding programs. This study aimed to analyze the chromosome number in P. notatum accessions under agronomic evaluation. Ploidy level was determined in 25 accessions. Two ploidy levels were detected, resulting in 21 tetraploid and four diploid accessions. The four diploid accessions originate from Argentina and Uruguay, in a region close to the origin of Pensacola, which is a diploid sexual cultivar of P. notatum. These new diploid accessions may be useful in the development of breeding programs of Paspalum species.

The aim of this study was to estimate the genetic parameters and predicted gains with selection of interspecific hybrids of Paspalum in relation to seed production traits Data were analyzed in randomized block design, with 23 genotypes arranged into ten blocks, according to the methodology of mixed models by the REML/BLUP procedure. The traits considered in the study were: number of total tillers/plant, number of reproductive tillers/plant, number of racemes/inflorescence, number of seeds/inflorescence, weight of a thousand seeds and seed production. Variability among genotypes, high heritability (>0.50), except total tillers (0.44) and number of racemes (0.36), and high accuracy (>0.90) were identified for all traits. The hybrids 10E5052, 10E4026, 10E507, 10E4025 and 10E40104 are among the top ten because they have high genetic values in three or more traits, indicating that these genotypes should be recommended for direct use in planting or potential parents to be used in new crosses.

The short life span, irregular forage production and susceptibility to weed colonization of cool-season grass–legume pastures are serious problems in grazing dairy systems in warm-temperate regions. The inclusion of warm-season species has the potential to mitigate these problems. In this study, we evaluated the effect of the inclusion of two warm-season grasses with different growth habits on seasonal forage biomass, soil cover and weed colonization. Three different pasture mixtures were evaluated under grazing: conventional pasture (CP) [tall fescue (Festuca arundinacea), white clover (Trifolium repens) and birdsfoot trefoil (Lotus corniculatus)], CP with Paspalum dilatatum and CP with Paspalum notatum (CP + Pn). Forage biomass and soil cover were sampled thirteen times during a 3-year trial, and sampling times were grouped by season for the analyses. The mixtures with Paspalum showed higher soil cover in the autumn, while in the winter CP had higher soil cover than CP + Pn. Competition with tall fescue was similar between mixtures with Paspalum, when considering biomass, but it was higher in CP + Pn when considering soil cover. The inclusion of P. notatum increased biomass during the autumn but decreased the mixture performance during winter by reducing tall fescue soil cover. The addition of a warm-season grass species with a moderate competing ability like P. dilatatum is likely to avoid a negative impact on the cool-season component of the pasture.