Panicum Coloratum Research Articles

Nutrient deficiency and hypoxia as constraints to Panicum coloratum growth in alkaline soils

AbstractAlkaline and saline–alkaline soils impose severe restrictions on plant growth. Panicum coloratum var. coloratum is a perennial C4 forage grass widely used in tropical and subtropical environments. Published information on its responses to alkaline soil conditions is scarce. The objectives of this study were (i) to characterize the effects of alkaline substrates on germination and initial growth in this species, (ii) to assess the influence of high pH in combination with reduced availability of either nutrients or oxygen and salinity, on plant growth and (iii) to evaluate some physiological traits potentially responsible for growth restrictions under alkaline soil conditions. Trials were conducted in a greenhouse. Germination and early plant survival were not affected by alkalinity. To isolate the effects of high pH, reduced nutrient and oxygen availability on growth, plants were grown either in neutral or alkaline soil, in hydroponics, in neutralized alkaline soil (with or without supplementary fertilization), or were flooded to induce hypoxia. Alkalinity effects on growth in hydroponics were milder than in soil. Growth in alkaline soil with nutrient supplement was still significantly lower (by 40%) than in neutral soil. Both alkalinity and hypoxia reduced growth non‐synergistically. These results show that studies of plant response to alkaline substrates carried out in aerated nutrient solutions can only partially address the complexity of this stress. Photosynthesis and PSII activity were among the physiological mechanisms negatively affected by alkalinity and may be partially responsible for the growth limitations observed in P. coloratum under alkaline conditions.

Assessment of Decay Coefficients of Allochthonous Litter for Sustainable Riparian Forage Agriculture and Environmental Monitoring: A Study in River Nyangores, Kenya

Research on decay profiles of grass detritus in lotic systems has received little attention in preceding years. An investigation was conducted on in-situ processing coefficients for three dominant forage species grown by farmers along the banks of River Nyangores in 2013. The objectives of the study were; (i) to determine in-situ processing coefficients for Pennisetum purpureum, Panicum coloratum and Chloris gayana, and (ii) to estimate detrital total phosphorus trends during incubation. It was hypothesized that no significant differences existed among the decay rates of the three grass species. A total of 186 leaf packs were deployed in River Nyangores at upstream and downstream sections separated by Bomet urban settlement for ten weeks, with a two-week withdrawal interval. Temperature normalized decay rates were estimated using an aquatic decay model. Total phosphorus was analyzed using the molybdate-calorimetric procedure with ultraviolet spectrophotometry. Data was analyzed using XLSTAT-2014 computer program. The in-situ decay coefficients ranged from 6.70795 x 10-4 dd-1 to 9.12355 x 10-4 dd-1. Covariance analysis (p<0.05) indicated significant differences for the decay rates among the three species, with higher in-situ processing coefficients recorded downstream than upstream for all the grasses. Litter phosphorus showed positive Pearson correlation with decay rates though not significant (p>0.05). During incubation, detrital phosphorus build-up was lower upstream at 6.4% than downstream at 13.8%. Highest decay rate was recorded for Chloris gayana hence it appears to be the most agro-ecologically sustainable as a riparian forage for River Nyangores. Bomet urban settlement seemingly contributes to shifts in ecological functioning of the river.

Effects of deferred forage as winter cover on spring growth of the tropical grasses Chloris gayana and Panicum coloratum

This pot study assessed the effects of deferring forage during autumn and leaving as winter cover on reducing cold damage to plants of 2 tropical (C4) grasses ( Chloris gayana and Panicum coloratum ) in a temperate environment in La Plata, Buenos Aires, Argentina. Mature plants were subjected to the following treatments: (i) autumn-deferred forage retained (DF) as control; and (ii) autumn-deferred forage removed (DFR) cutting at 15 cm from soil level at beginning of winter. This experiment had 10 replicates per treatment and 1 plant per pot (experimental unit). Plants of both species were extracted from a commercial beef farm and transplanted into an experimental garden in pots where they grew outdoors from 2 February to 23 May (111 days) when treatments were applied. After winter, both grasses were cut to 15 cm in early spring (27 September) and spring growth was measured in November. Shoot biomass was harvested at ground level and separated into lower and upper layers (above and below 15 cm), leaf blades, sheaths and stolons. Daily air temperature, relative humidity and frost events were registered. Allometric analysis of shoot biomass was performed to determine the stress incidence by cold. DF plants achieved 55‒80% higher shoot biomass than DFR plants during spring in both species. The allometric analysis revealed for P. coloratum significant relationships between shoot biomass from plant compartments (lower and upper layers, leaf blade and sheath) and total shoot biomass in both treatments, indicating good cold tolerance. However, for C. gayana, unlike DF plants, DFR plants were strongly stressed, showing a lack of shoot biomass fit. These results suggest that deferring autumn forage growth and retaining as winter cover may improve survival during winter and productivity during spring of these two tropical grasses in temperate pastoral systems. However, the study needs to be repeated under field conditions and under grazing or cutting over a number of years in different situations to verify these preliminary results. Keywords : Winter cover, cold damage, frost protection, pasture management.

Salt tolerance variability among stress‐selected Panicum coloratum cv. Klein plants

AbstractThis work assessed intracultivar variability for salt tolerance within Panicum coloratum cv. Klein, explored some physiological parameters potentially associated with it and evaluated the contribution of cell division and expansion to the decreased leaf length observed under salinity. Individual plants that had survived severe stress environments in an established pasture were collected and clonal families were obtained by vegetative propagation. These were evaluated in a greenhouse, in pots with an inert substrate irrigated with nutrient solution containing 0, 200 or 400 mm NaCl. Salt tolerance was assessed from growth variables expressed as a percentage of non‐salinized controls. Changes induced by salinity in carbon fixation, soluble sugars and compatible solutes were also measured. The selected plants showed 33% higher salt tolerance than plants from the same cultivar obtained from seeds, and variability for salt tolerance was detected within the group, suggesting these plants could be valuable germplasm for breeding programmes for saline areas. All selected plants accumulated low leaf blade Na concentrations (< 0·1 mm g−1 dry weight on average), and K concentrations tended to remain high under salinity. A kinematic analysis indicated a reduction in the number of cells in the division‐only zone was the main cause of shorter leaves under stress. Although plants showed some differences in all these traits, they were not related to salt‐tolerance variability within this group of stress‐tolerant plants.

Effects of Rice Straw, Annual Ryegrass Straw and Klein Grass Hay on Disappearance Rates of Nutrients in the Rumen and CH_4 Emission in Hanwoo Cows

Effects of Rice Straw, Annual Ryegrass Straw and Klein Grass Hay on Disappearance Rates of Nutrients in the Rumen and CH_4 Emission in Hanwoo Cows

Methane production and in vitro digestibility of low quality forages treated with a protease or a cellulase

The objective was to assess the impact of application of two enzyme mixtures on the in vitro dry matter digestibility, neutral detergent fibre digestibility, net cumulative gas production and methane production after 24 h of incubation of Milium coloratum (formely Panicum coloratum) and a Patagonian meadow grassland. A protease (Protex 6-L) and a fibrolytic enzyme (Rovabio) were assessed at three application rates (30, 60 and 90 mg/100 mL of distiller water) on the substrates. Meadow samples were higher to Milium ones (P < 0.05) for in vitro dry matter digestibility and net cumulative gas production at 24 h. Nevertheless, Milium was ~11% higher than meadow (P < 0.05) for methane when expressed as a proportion of digested dry matter (g/kg). Rovabio did not induce differences in any variable, but the addition of Protex reduced (P < 0.05) in vitro dry matter digestibility in both substrates without bringing about differences in methane production. Collectively, the addition of these enzymes did not benefit in vitro ruminal fermentation of low quality forages.

Comparison of Growth Characteristics, Forage Production and Feed Values of Bermudagrass, Teffgrass and Kleingrass as Annual Forage Crop in Summer

Hyung Soo Park*, Ki Choon Choi, Ji Hea Kim, Sang-Hoon Lee and Jong Seong JungNational Institute of Animal Science, Cheonan, 330-801, KoreaABSTRACTThis study was conducted from 2013 to 2014 to explore the feasibility of the cultivation of warm-season grass as an annual Korean forage crop, while concurrently evaluating the characteristics and forage production of warm-season grass in Korea. The experimental design was a randomized block design(RBD) with three replications. Five bermudagrass[Cynodon dactylon (L.) Pers.] cultivars, two teffgrass(Paspalum notatum Flugge) cultivars, and a Kleingrass[Panicum coloratum L.] cultivar were compared for forage production and quality in the middle region of Korea. After seeding, the numbers of days until seedling emergence for bermudagrass and kleingrass were observed at approximately day 11 and day 12, respectively. The heading dates of teffgrass and kleingrass were on July 12 and July 26, respectively. The dry matter(DM) yield of bermudagrass Tifton 85 was usually greater than the other entries. The crude protein content(CPC) and total digestibility nutrient(TDN) for the teffgrass cultivars were usually greater than the other entries at all study sites. The acid detergent fiber(ADF) and in vitro DM digestibility(IVDMD) were similar across all cultivars. (Key words :Warm season grass, Production, Feed value, Bermudagrass, Teffgrass)

Ability to recover overrides the negative effects of flooding on growth of tropical grasses Chloris gayana and Panicum coloratum

This study assessed the flooding tolerance of the tropical grasses Chloris gayana Kunth and Panicum coloratum L. at different times of the year: (i) late winter flooding for 50 days (WF), (ii) early spring flooding (SF) for 20 days, and (iii) long-term flooding covering both periods (WF + SF, 70 days). A growth period under well-watered conditions was allowed after each flooding event to assess recovery of plant species. Plants were harvested after each flooding event and at the end of the recovery period. Panicum coloratum had higher tolerance to WF than C. gayana. Treatment WF did not affect biomass in P. coloratum, whereas it reduced biomass of flooded plants by 38% in C. gayana. Treatment SF did not differentiate the species for tolerance; both registered moderate reduction in their growth (20–30%). Under WF + SF, C. gayana showed additional reduction in its growth over that observed when subjected separately to either WF or SF, whereas P. coloratum did not. Both species displayed remarkably fast recovery from flooding when temperatures rose during early summer, attaining biomass equivalent to that of non-flooded plants 1 month after water subsided. Therefore, although P. coloratum appears slightly more tolerant during flooding than C. gayana, both species are promising for introduction in temperate lowland grasslands.

Screening of biomass production of cultivated forage grasses in response to mycorrhizal symbiosis under nutritional deficit conditions

AbstractArbuscular mycorrhizal fungi (AMF) colonize the root systems of most natural grassland species and usually increase plant growth by enhancing nutrients provision. This effect on growth responses of cultivated forage grasses is scarcely known, particularly under nutritional deficit conditions. We examined total biomass production, aboveground and belowground biomass and tillering of three temperate and three tropical cultivated forage grasses. Seedlings of each species were inoculated with a mixture of mycorrhizal fungi and later grown for 5 months under nutritional deficit conditions. The mycorrhizal symbiosis promoted aboveground and belowground biomass production in five out of six grass species. Grass species differed in their mycorrhizal responsiveness: tropical grasses (Panicum coloratum cv. Klein = Brachiaria brizantha cv. Marandú > Paspalum dilatatum cv. Primo) responded better than temperate (Festuca arundinacea cv. Royal > Agropyron elongatum cv. Hulk), while the temperate Dactylis glomerata cv. Porto did not respond to AMF inoculation. In four of the species, the changes observed in aboveground biomass were explained by the total number of tillers, while, in P. dilatatum, changes were accounted for by the individual weight of mature tillers. On the whole, the screening of cultivated forage grasses revealed that tropical grasses were highly responsive to mycorrhizae, in contrast to a lower effect on the growth of temperate grasses.

중남부지역에서 난지형 목초의 생육특성, 월동성 및 사초생산성 평가

Field studies were conducted from the years 2009 to 2012 in order to determine the cultivation limit as well as to evaluate the characteristics and forage production of warm season grass in Korea. Two bermudagrass [Cynodon dactylon (L.) Pers.] cultivars, two bahiagrass (Paspalum notatum Flugge) cultivars and a Kleingrass [Panicum coloratum L.] cultivar were compared for forage production and quality in the mid-southern regions of Korea. The experimental design was a randomized block design (RBD) with three replications. The number of days to seedling emergence for bremudagrass and bahiagrass was observed as approximately 12 days and 28 days after seeding, respectively. In Kwangju, the heading dates of bahiagrass and kleingrass were 21 August and 10 July, respectively,. Warm season grass did not winter in the mid-regions (Kimjea, Cheonan) of Korea. All of the Bermudagrass cultivars had higher dry matter (DM) than bahiagrass at the first harvest. The dry matter yield of kleingrass was usually greater than the other entries at all study sites. Peak forage DM production of bermudagrass and bahiagrass cultivars occurred in June and July, respectively. The contents of crude protein (CP) and total digestibility nutrient (TDN) for bermudagrass cultivars were usually greater than the other entries at all study sites. Further, acid detergent fiber (ADF) and in vitro DM digestibility (IVDMD) were similar across all cultivars. (

Loss of a large grazer impacts savanna grassland plant communities similarly in North America and South Africa

Large herbivore grazing is a widespread disturbance in mesic savanna grasslands which increases herbaceous plant community richness and diversity. However, humans are modifying the impacts of grazing on these ecosystems by removing grazers. A more general understanding of how grazer loss will impact these ecosystems is hampered by differences in the diversity of large herbivore assemblages among savanna grasslands, which can affect the way that grazing influences plant communities. To avoid this we used two unique enclosures each containing a single, functionally similar large herbivore species. Specifically, we studied a bison (Bos bison) enclosure at Konza Prairie Biological Station, USA and an African buffalo (Syncerus caffer) enclosure in Kruger National Park, South Africa. Within these enclosures we erected exclosures in annually burned and unburned sites to determine how grazer loss would impact herbaceous plant communities, while controlling for potential fire-grazing interactions. At both sites, removal of the only grazer decreased grass and forb richness, evenness and diversity, over time. However, in Kruger these changes only occurred with burning. At both sites, changes in plant communities were driven by increased dominance with herbivore exclusion. At Konza, this was caused by increased abundance of one grass species, Andropogon gerardii, while at Kruger, three grasses, Themeda triandra, Panicum coloratum, and Digitaria eriantha increased in abundance.

Effects of Seed Proportion and Planting Pattern on Dry Matter Yield, Compatibility and Nutritive Value of <i>Panicum coloratum</i> and <i>Stylosanthes guianensis</i> Mixtures under Bako Condition, Western Oromia, Ethiopia

Panicum coloratum (PC) and Stylosanthes guianensis (SG) mixed pasture was established to assess the effect of seed proportion and planting pattern on Dry Matter Yield (DMY), compatibility and nutrient content of the mixed stand. Seeds of PC and SG were mixed as 50%PC+50% SG and 25% PC+75% SG and sown in same row, alternate row and broad casting pattern. A randomized complete block design with four replications was used to layout the experiment. The 50%PC+50%SG proportion resulted in significantly (p<0.01) higher DMY for PC (p<0.0001) while the 75% SG+25%PC mixture resulted in significantly higher DMY of SG (p<0.0001). For PC and SG, and total herbage yield, an alternate row planting pattern gave significantly highest (p<0.0001) yield, followed by broadcasting. Planting along the same row resulted in inferior values (p<0.0001) for all parameters, which perhaps is induced by the severity of competition between species. The RY (Relative Yield), LER (Land Equivalent Ratio),and CR (Competitive Ratio) values also imply similar trends for DMY of the component species. The legume DMY steadily increased from first to third year for the 75% SG+25% PC proportion. It can thus be concluded that the 50%PC+50SG proportion sown in alternate pattern was favorable for DMY in PC whereas the 25%PC+ 75%SG proportion combined with alternate rowpattern was appropriate for the legume. Intercropping SG into PC sward at 25%PC+75%SG mixed proportions also improved the CP content, IVDMD and reduced NDF content.

In vitro fermentation, digestibility and methane production of tropical perennial grass species

This study characterised 16 tropical perennial grass species in terms of in vitro methane output and related their digestibility and rumen fermentation with methane output. The grass samples were collected, dried in a forced oven, and ground and analysed for nutrient composition. In vitro gas production and organic matter digestibility (IVOMD) were determined using rumen fluid collected, strained and anaerobically prepared. A semi-automated system was used to measure gas production through in vitro incubation at 39°C. Anthephora argentea and Stipagrostis ciliate produced the highest concentration of methane in terms of g kg–1 digestible dry matter (DDM) and g kg–1 digestible organic matter (IVOMD). Cenchrus ciliaris, Setaria verticillata and Panicum coloratum produced the lowest (P < 0.05) methane when expressed in terms of g kg–1 DDM and g kg–1 IVOMD. Ash, ether extract, non-fibrous carbohydrate, neutral and acid detergent insoluble nitrogen, and crude protein were negatively correlated with methane production. Methane production positively correlated with neutral and acid detergent fibre, cellulose and hemicellulose. It is important to focus on screening and selecting perennial grass with higher nitrogen content and low methane production to mitigate methane production under tropical conditions.

국내 이용 주요 조사료원의 영양소 함량 및 반추위 In situ 소실율 평가

This study is conducted to estimate the nutrient compositions and in-situ ruminal disappearancerates of roughage sources which are commonly used in South Korea. Twelve types of roughage sources are being selected based on surveys from more than 50 farms, and 12 samples from various farms and companies are collected and analyzed for their nutritive components and minerals. Two Hanwoo steers (BW 526 ± 14 kg) with ruminal cannula are used to investigate in situ ruminal degradability. Five roughage sources, timothy hay, alfalfa pellet, rice straw, klein grass hay and tall fescue straw, are all selected from 12 roughage sources above for further experiments. Overall, the nutrient components and minerals from the 12 roughage sources have shown low values when comparing with standard tables of feed compositions in Korea. In situ dry matter disappearance rate is recorded as high in order of klein grass, timothy, alfalfa pellet, tall fescue and rice straw. In situ crude protein disappearance rate is high in order of alfalfa pellet, klein grass, timothy, tall fescue and rice straw. (

Effect of age of regrowth on yield and herbage quality of Panicum coloratum under sub humid climatic conditions of Ethiopia

The effect of stage of harvest on dry matter (DM) yield and herbage nutritive value of Panicum coloratum under sub humid climatic conditions of western Ethiopia was evaluated. Three harvesting stage treatments (8, 10 and 12 weeks of regrowth age) were assessed. The herbage DM yield (P<0.05); and leaf (P<0.05) and stem component DM yields (P<0.01); and leaf to stem ratio (P<0.001) values were significantly affected by the age of regrowth. Herbage and stem component DM yields; and stand density exhibited an increasing trend with age of regrowth. Mean herbage DM yield ranged from 11.04±0.91tha-1 to 14.71±0.91tha-1. The crude protein (CP) content was 8.28±0.34 and 8.43±0.34% for the 8 and 10 weeks treatments, respectively, while it declined to 6.27±0.34% for samples harvested at 12 weeks of age. Mean values of neutral detergent fibre (NDF) were generally high for all harvesting treatments, the values ranging from 74.02±0.85 to 77.50±0.85%. The in vitro DM digestibility (IVDMD) values ranged from 46.92% for the 12 weeks to 53.65% for the 8 week harvests. The calcium concentration ranged from 0.38±0.05% for the 10 weeks treatment to 0.51±0.05% for that of 10 weeks. Similarly, phosphorus content varied from 0.13±0.005 to 0.15±0.005% and no clear trend was observed with stage of maturity. It was recommended that the grass be harvested at 8 weeks of regrowth age for optimal yield and quality. Key words: Dry matter yield, leaf to stem ratio, crude protein, neutral detergent fibre, in vitro dry matter digestibility, calcium, potassium.

Selection by seed weight improves traits related to seedling establishment in Panicum coloratum L. var. makarikariense

AbstractSelection for heavy seed was implemented to overcome establishment problems in Panicum coloratum var. makarikariense. A collection covering the genetic diversity of the species available in Argentina was used as a base population (BP), and two cycles of recurrent phenotypic selection to increase seed weight were performed. Seedlings, obtained from seeds from each cycle and the BP, were further evaluated in the greenhouse. An increase of 17% in mean seed weight was obtained after two cycles of recurrent selection. No differences in germination or emergence were detected among the selected materials and the BP. However, seedlings from selected materials were taller and showed higher leaf elongation rate, adventitious roots elongation rate and total growth rate than that from BP. This research also revealed that in P. coloratum var. makarikariense, more vigorous seedlings can be selected from genotypes that produce heavier seeds.

Use of Awamori-pressed Lees and Tofu Lees as Feed Ingredients for Growing Male Goats.

Awamori is produced by fermenting steamed indica rice. Awamori-pressed lees is a by-product of the Awamori production process. Tofu lees is a by-product of the Tofu production process. Research was conducted to test if dried Awamori-pressed lees and Tofu lees can be used as a mixed feed ingredient for raising male goats. Eighteen male kids were divided into three groups of six animals (control feed group (CFG), Awamori-pressed lees mixed feed group (AMFG), Tofu lees mixed feed group (TMFG)). The CFG used feed containing 20% soybean meal as the main protein source, while the AMFG and TMFG used feed mixed with 20% dried Awamori-pressed lees or dried Tofu lees. The groups were fed mixed feed (volume to provide 100 g/d increase in body weight) and alfalfa hay cubes (2.0 kg/d) twice a day (10:00, 16:00). Klein grass hay and water was given ad libitum. Hay intake was measured at 10:00 and 16:00. Body weight and size measurements were taken once a month. At the end of the experiment, a blood sample was drawn from the jugular vein of each animal and the carcass characteristics, the physical and chemical characteristics of loin were analyzed. DCP and TDN intakes in AMFG and TMFG showed no significant difference to the CFG. Cumulative measurements of growth in body weight and size over the 10 mo period in the AMFG and TMFG were similar to the CFG. Blood parameter values were similar to those in normal goats. Dressing carcass weight and percentages, and total weight of meat in the AMFG were similar to that in the CFG, but smaller in the TMFG. The compressed meat juice ratio was higher in both the TMFG and AMFG than the CFG. While the fat in corn, Awamori-pressed lees, and Tofu lees contains more than 50% linoleic acid, the loin fat in both the AMFG and TMFG was very low in linoleic acid due to the increase in the content of oleic acid, stearic acid, and palmitic acid. This indicates that feeding on AMF and TMF does not inhibit hydrogenation by ruminal microorganisms. As in the CFG, the total essential and non-essential amino acids in the loin of the AMFG and TMFG were well balanced. Compared to the CFG, the AMFG and TMFG were high in taurine and carnosine. The results indicate dried Awamori-pressed lees and Tofu lees can be used as a feed ingredient for raising male goats.

Soil Organic Carbon Pools Under Switchgrass Grown as a Bioenergy Crop Compared to Other Conventional Crops

Switchgrass (Panicum virgatum L.) has been proposed as a sustainable bioenergy crop because of its high yield potential, adaptation to marginal sites, and tolerance to water and nutrient limitations. A better understanding of the potential effects of biomass energy crop production practices on soil biological properties and organic matter dynamics is critical to its production. Our objective was to evaluate changes in C pools under a warm-season perennial switchgrass in different soils compared to typically-grown crops collected at College Station, Dallas, and Stephenville, TX in February 2001. Sampling depths were 0–5, 5–15, and 15–30 cm. Switchgrass increased soil organic C (SOC), soil microbial biomass C (SMBC), mineralizable C, and particulate organic matter C (POM-C) compared to conventional cropping systems. Soil C concentrations were in the order: long-term coastal bermudagrass [Cynodon dactylon (L.) Pers.] < switchgrass or kleingrass (Panicum coloratum L.) planted in 1992 > switchgrass 1997 > conventional cropping systems. Soil C concentrations tended to increase with increasing clay content. Greater microbial biomass C followed the order of Dallas > College Station > Stephenville, and ranged from approximately 180 mg C kg−1 soil at Stephenville to 1900 mg C kg−1 soil at Dallas. Particulate organic C was more sensitive than other fractions to management, increasing as much as 6-fold under long-term coastal bermudagrass compared to conventional cropping systems. Our study indicated that conversion of conventional cropping systems into switchgrass production can sequestrate more SOC and improve soil biological properties in the southern USA.

Collection and morphological characterization of Panicum coloratum L. in Argentina

Panicum coloratum (Poaceae) is a perennial grass native to South Africa, distributed all over the world, but poorly adopted by ranchers in Argentina. Adapted to a wide range of soil and climatic conditions, it constitutes a good forage resource for zones with edaphic and climatic restrictions, where cattle rising activities are here displaced. The high polymorphism in the species has made it difficult to delineate sub specific taxonomic categories. It has been classified in botanical varieties, types and/or cultivars. In order to document the morphological variability in P. coloratum and to investigate the differences between var. makarikariense and var. coloratum, a collection was gathered in INTA Rafaela composed by fourteen accessions from different provinces of Argentina: six accessions of var. makarikariense and eight from var. coloratum. The evaluation of 152 individuals gives evidence of a wide morphological variation in the collection in traits related to forage and caryopses production; seven out of nine traits showed significant differences between var. makarikariense and var. coloratum. Based on the study of local type specimens, a morphological key to distinguish between P. coloratum varieties is provided. These results report new information about the diversity in P. coloratum in Argentina and provide valuable insights for future use of the collection as the base material of a breeding program.

Effect of Farmyard Manures from Cattle with Different Feeding Systems and Co-digestion Substrates on Mineralization Characteristics and Fertilizing Efficiency in Tropical Colored Guineagrass (Panicum coloratum L.)

Effect of Farmyard Manures from Cattle with Different Feeding Systems and Co-digestion Substrates on Mineralization Characteristics and Fertilizing Efficiency in Tropical Colored Guineagrass (<i>Panicum coloratum</i> L.)