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Livestock systems based on subtropical and tropical pastures are characterized by the low productivity of livestock due to the poor nutritional value of the forage (low nitrogen concentration and digestibility, and high fiber and lignin concentrations). These conditions lead to low productivity and, consequently, high absolute emissions of methane (CH4) per unit of product. Dry distilled grains with solubles (DDGS) are the main by-product resulting from ethanol production, and they are characterized by their high-energy fibrous and protein content, thus becoming an option for the supplementation of low-quality forage. This research investigated the effects of dietary DDGS inclusion on dry matter digestibility (DMD) and enteric CH4 emission. Eight adult sheep of 64 ± 8 kg live weight were used. The duration of the study was 54 days, divided into two periods (changeover design), which comprised a 17-day pre-experimental period and 10 days for experimental data collection. Animals were allocated to one of two treatments used: hay (H) as a control treatment, where animals were fed with Rhodes grass hay alone; and H + DDGS, where animals were fed with H supplemented with DDGS. CH4 emissions were estimated using the sulfur hexafluoride (SF6) tracer technique. Diets containing DDGS increased DMI by 22% (p < 0.05) and reduced daily CH4 emissions by 24% (g/d), the CH4 yield by 35% (g/kg DMI), and the average value of CH4 energy per gross energy intake (Ym) by 44%, compared to the control treatment (p < 0.05). The experiment demonstrated that supplementation with DDGS in low-quality roughage reduced daily CH4 emissions, yields, and Ym. View Full-Text Instituto de Patobiología Fil: Gere, José. Universidad Tecnológica Nacional. División Investigación y Desarrollo de Ingenierías; Argentina Fil: Gere, José. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Feksa Frasson, Mónica. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina Fil: Wawrzkiewicz, Marisa. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina Fil: Fernández Pepi, María Gabriela. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina Fil: Ramos, María Laura. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina Fil: Bualo, Ricardo Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; Argentina Fil: Ceron Cucchi, Maria Esperanza. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Patobiología; Argentina Fil: Jaurena, Gustavo. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal; Argentina

An experiment was conducted twice concurrently at Vom in Plateau State Nigeria in 2011 to evaluate the effects of three animal based organic fertilizers and three rates of application on the growth, seed and herbage yields of Rhodes grass (Chloris gayana var. Callide). This study involved three types (poultry, rabbit and sheep dung) of animal fertilizer and three rates (0, 25 and 50 t ha-1) of application in a 3 x 3 factorial arrangement fitted into randomized complete block design and replicated three times. Animal fertilizers significantly (p < 0.05) increased growth, seed, fresh herbage and dry matter yields of Rhodes grass. Generally, fertilizers from poultry and rabbit were similar and better (p < 0.05) than that of sheep in the enhancement of the measured variables. At 6 weeks after fertilizer application (WAF), fresh herbage yield was in the range of 14.6 – 48.3 t ha-1 whereas dry matter yield ranged from 4.7 – 13.9 t ha-1 while seed yield was 1.8 – 2.3 t ha-1. At 12 WAF, rabbit fertilizer produced significantly higher values than sheep fertilizer by 21.2 % for sward height, 70.1 % for fresh herbage yield and 61.4 % for dry matter yield. The correlation coefficients among the measured variables were positive and highly significant. The highest correlation recorded (0.937**) was between fresh herbage and dry matter yields. The study indicated that application of either rabbit or poultry fertilizer can suitably enhance Rhodes grass growth for higher herbage and seed yields. The study also showed that 25 and 50 t ha-1 of animal fertilizers on Rhodes grass yielded similar results. With adequate fertilizer application, Rhodes grass can produce sufficient herbage to meet the nutritional requirement of several ruminant livestock. It is not economical to apply more than 25 t ha-1 of animal fertilizers to Rhodes grass if they contain more than 1.21 % of nitrogen.

A grazing trail was conducted to evaluate the effect of five stocking rates 12, 18, 24, 30 and 36 sheep/ha) on the chemical composition of Rhodes grass (Chloris gayana)- Stylo (Stylosanthes guinanensis) pastures in Nigeria. The pastures were set stocked for 154-210 days over five grazing periods. Stocking rate had no significant (P>0.05) effect on the crude protein (CP), phosphorus (P), potassium (K), calcium (Ca) and magnesium Mg) contents of the pasture components. The concentrations of CP, K and Ca declined as plants matured while the levels of CP, P and Ca in the stewm were short of the recommended levela for rams. Acid detergent lignin (ADL) and fibre (ADF) were not affected by stocking rate but the neutral detergent fibre (NDF) of the components increased with stocking rate. The non-persistence of Style beyond one grazing period lowered the chemical composition of the pasture thus the need to incorporate more persistent legume(s) with the grass.

Mixed pastures of Rhodes grass (Chloris gayana cv. Callide) and Stylo (Stylosanthes guianensis cv. Cook) were evaluated at fi.ve slacking rate, 12, 18, 2 4, 3 0 and 36 rams/ha over five grazing periods at Shika, Nigeria. The pastures were continuously grazed for 154 to 210 days beginning from late rainy into dry season (August to April). Dry matter yields of stem, leaf stem + leaf of C gayana, green material and total herbage declined (P

The aim of this study was to determine the biochemical and haematological profiles of Kalahari Red goats reared in the tropical environment. The Kalahari Red goats were imported into Nigeria from South Africa by the Federal University of Agriculture Abeokuta, Nigeria. The study was carried out on fifty animals of both sexes. The animals were managed under semi-intensive system where they were allowed to go out and graze on paddocks during some part of the day and brought back to the pens in the evening. The goats were fed with concentrate and grazed on sown pastures of Chloris gayana and Stylosanthes amata. Water Rwas given ad-libitum. The serum biochemical analysis was determined using Randox analysis kits. The sex of each animal was noted and recorded. The packed cell volume, haemoglobin concentration, red blood cell count, white blood cell count, neutrophils, lymphocytes, monocytes, eosinophils and basophils were determined as haematological parameters while total protein, albumin, globulin, sodium, potassium, calcium and phosphorus were determined in serum analysis. The results showed that there was no significant (p>0.05) difference in all the haematological parameters determined across sex. There were significant (p

The glomalin produced by arbuscular mycorrhizal fungi has beneficial effects on soils. We studied the vertical profile of glomalin related soil protein (GRSP) in pasturelands grown under saline soi...

Land degradation is a global problem leading to a diminished production capacity of the rangelands. The consequence is reduced potential to provide ecosystem services and increased vulnerability to the inhabitants. Biological soil water conservation measures can reverse the trend. Different communities prefer different grass species for rehabilitation as communities vary in location, needs, priorities, preferences and the type of livestock reared. This study, therefore, sought to identify the suitable grass species for soil erosion and rehabilitation from the community in Keekonyoie ward In Narok county, Kenya. Data collection was through individual interviews, focus groups, key informant interviews and field observations. Results showed that level, indicators, causes and impacts are known to the community. Cynodon plectostachyus (76%), Chloris gayana (73%), Pennisetum clandestinum (69%), Cymbopogon citratus (46%) and Themeda triandra (42%) were most preferred for rehabilitation and soil erosion control. The primary reason for the grasses choice was a yearlong provision of livestock feed. Needs and livelihood priorities significantly influence decision-making among the Maa-speaking community in Keekonyoie ward. We recommend consideration of community needs, priorities and preferences in the selection of grass species for rehabilitation to increase the adoption measures that can reverse land degradation Key words: Indigenous knowledge, community perceptions, range grass species, rehabilitation, land degradation, Narok.

A field experiment was conducted during summer season of 2007 at the Demonstration Farm of the Faculty of Agriculture, University of Khartoum, Shambat, Sudan, to investigate the effect of seed rate and NPK fertilization on yield and quality of Rhodes grass forage (Chloris gayana L. Kunth) cv. Finecut. The treatment consisted of three seed rates (SDR1, SDR2 and SDR3) namely 5, 10 and 15 kg/ha and three NPK fertilizer levels (F0, F1 and F2) namely 0, 120 and 240 kg/ha respectively. NPK fertilizer components were N17 P17 K17. The experiment was laid out in a Factorial CRBD with four replications. The results showed that seed rate significantly increased forage fresh and dry yield. NPK fertilization significantly increased forage fresh and dry yield. Neither seed rate nor NPK fertilization were significantly affected crude protein and fiber content of leaves and stems of Rhodes grass, but the increase in seed rate and fertilizer levels slightly increased crude protein and decreased fiber percentage. Seed rate ×NPK fertilization interaction showed significant effect on crude protein and crude fiber contents. The highest protein percentage obtained under SDR2 (10kg/ha) with highest NPK fertilization level F2 (240 kg/ha), and lowest value obtained under SDR1(5kg/ha) with NPK fertilization F1(120kg/ha) and SDR1(5kg/ha) under control of fertilizer treatment (F0). Regarding crude fiber, highest value obtained under SDR2(10 kg/ha) with NPK fertilization F1 (120kg/ha) and SDR3 (15 kg/ha) under control treatments of fertilization (F0).

This study was conducted in Adami-Tullu Jido-Kombolcha and Arsi Negelle districts, south central Ethiopia. The objectives of the study were to evaluate the interactive effects of grazing management systems and rangeland sites on dry-matter production and chemical composition of herbaceous plants in south central Ethiopia. Data were analyzed using GLM procedure in SPSS 16.0 version, which was used for mean comparisons using post-hoc t-test that can be employed to compare mean differences for enclosure and open-grazed areas. To test the effects of management systems and altitudinal variation on dry-matter production and chemical composition of herbaceous species, mixed model analysis was employed using sample site as a random variable while grazing management systems and altitude were fixed variables. A total of 28 herbaceous species were identified. Of the identified herbaceous species, 20 species were grasses, 2 species were legumes while 6 species were forbs. Among the recorded grass species, some were highly desirable, while others were in the categories of intermediate in terms of desirability and less desirable. We identified the dominant and common grass species that included: Arstida adscensionis, Cenchrus ciliarus, Chloris gayana, Chloris roxburghiana, Bothriochloa insculpta, Eragrostis papposa, Heteropogon contorus, Panicum maximum, Indigofer spinosa, Tephrosia pumila, Sporobolus pyrmidalis, Themeda triandra, B. nigropedata, Ocimum basilicum, Amaranthus dubis, Tribulos terrestris and Achyrantes aspera. The chemical composition of herbaceous plants were analyzed for DM, CP, NDF, ADF, ADL and Ash comparing two grazing management systems and three rangeland sites as patch mosaic units. The results of the present analysis showed that the average CP content in the open-grazed areas was significantly (P

A field experiment was conducted during the 2016 and 2017 rainy seasons at Centre for Agriculture and Pastoral Research (CAPAR) of the Usmanu Danfodiyo University Sokoto, Nigeria to study the effect of nitrogen fertilizer and inter-row spacing on Leave length and Leave width of Rhodes grass as indices of growth. A factorial combination of five fertilizer levels (0, 100, 120, 140 and 160 kgNha-1) and three inter row spacing (30, 50 and 70 cm) were used, making fifteen treatments combinations, which were laid out in a RCBD replicated four times. Determination of leave length and leave width was done at 3, 6, 9 and 12WAS using a meter rule. The data obtained were statistically analyzed by using analysis of variance (ANOVA), using the GenStat 64-bit Release 17.1 (software) to elucidate the valid information from the data. The result revealed that, application of 160 KgNha-1 generally produced plants with longer and broader (P0.05) effect of inter row spacing in both 2016, 2017 and the years combined, inter-row spacing of 70 cm showed superiority amongst the treatments in the leaves length and leave width parameters investigated as compared to 50 and 30 cm spacings.

Degradation of crop and grazing lands is a pervasive problem that negatively impacts agricultural productivity and livelihoods of crop-livestock farmers in the Blue Nile basin of Ethiopia. Area enclosure together with a cut and carry livestock feeding system is often advocated as an approach for the regeneration of degraded grazing lands. This paper reports the results of a two-year farmer participatory study conducted to assess the effects of infiltration trenches (ITs) and Chloris gayana Kunth (Rhodes grass; cultivar Masaba; tetraploid; C4 grass species) reseeding on restoration of degraded grazing lands. A split plot design was used with IT as the main plot and C. gayana reseeding as a sub-plot on 28 private grazing plots under enclosure. The results showed that IT alone increased soil moisture content and prolonged the growing period. IT and C. gayana reseeding together significantly (P ≤ 0.05) increased herbage dry matter yield and improved soil chemical properties. The highest mean herbage dry matter yield (21 Mg ha−1 per cut) was recorded for plots treated with IT and reseeded with C. gayana. The higher herbage dry matter yield was attributed to increased soil moisture and the resultant prolonged growing period induced by the trenches coupled with the ability of C. gayana to effectively utilize the retained water. The results suggest that an integrated land management approach involving enclosure, in-situ water conservation and C. gayana reseeding can rapidly increase biomass productivity on degraded grazing lands while also enhancing soil quality with concomitant livelihood benefits for farmers.

A field experiment was conducted during the 2016 and 2017 rainy seasons at Centre for Agriculture and Pastoral Research (CAPAR) of the Usmanu Danfodiyo University Sokoto, Nigeria to study the effect of nitrogen fertilizer and inter-row spacing on herbage yield and some yield parameters of Rhodes grass. A factorial combination of five fertilizer levels (0, 100, 120, 140 and 160 kgNha-1) and three inter row spacing (30, 50 and 70 cm) were used, making fifteen treatments combinations, which were laid out in a RCBD replicated four times. Determination of herbage dry matter yield at the end of 12 weeks post planting was carried out using a 0.25 m2 (0.5 m x 0.5 m) area metallic frame (Quadrat). The herbage was harvested at 5 cm above ground level using hand Sickle from the four plots for each treatment. The samples collected ware oven dried for the determination of dry matter yield, while determination of number of leaves and number of tillers per plant was done by counting the numbers of individual leave and tillers of each of the representative plant sample. The result revealed that, Application of 160 KgNha-1 generally produced higher (P < 0.05) dry matter yield, number of leaves and number of tillers compared to the rest of the treatment, There was no significant (P > 0.05) effect of inter row spacing in both 2016, 2017 and the years combined on herbage dry matter yield, however significant (P < 0.05) effect of spacing was observed in 2016, 2017 and the years combine on the numbers of leaves and numbers of tiller. Inter-row spacing of 70cm showed superiority among the treatments in the herbage yield compositions investigated compared to 50 and 30cm spacings.

An experiment was conducted in Shambat (2016-2017) in the demonstration farm of the College of Agricultural Studies, Sudan University for Science and Technology, to study the effect of variety and nitrogen fertilization on the agronomic performance of Rhodes grass. Two Rhodess grass varieties (Fine cut and Reclaimer) and 2 nitrogen doses plus control were studied across seven cuts. The treatments were replicated four times in split plot experiment with fertilizer doses assigned to the main plots and the varieties to the sub-plots. The data collected included forage yield, plant height and days to 50% flowering.

Introduction: Ecological niche modeling is a fundamental tool to know the areas suitable for the establishment of silvopastoral systems, based on the environmental requirements of the species. Objectives: To model the ecological niche of the forage species Chloris gayana Kunth and Eragrostis curvula (Schrad.) Nees, and the conifers Pinus devoniana Lindley, Pinus lawsonii Roezl ex Gordon and Pinus montezumae Lambert and to identify potential areas for silvopastoral systems. Materials and methods: The ecological niche was modeled based on data from georeferenced collection sites in Mexico and 23 environmental variables. Subsequently, areas were identified and the extent, where forage species converge with conifers in both agricultural and forest areas, was estimated. Results and discussion: Potential areas for silvopastoral systems with the five species were found mainly in the Neovolcanic Axis and the Sierra Madre del Sur, with a greater area suitable for agricultural areas compared to forestry areas. Pinus devoniana had the largest potential area to be intercropped with C. gayana and E. curvula. The ecological niche models had high predictive capacity with an area under the curve values greater than 0.93. Altitude and annual temperature range were the most important variables. Conclusions: Mexico has the potential to establish silvopastoral systems with the species understudy in the center and south of the country, which could contribute to decreasing soil degradation, provide forage for livestock and maintain tree cover for agricultural and forest areas.

A field experiment was conducted during the 2016 and 2017 rainy seasons at Centre for Agriculture and Pastoral Research (CAPAR) of the Usmanu Danfodiyo University Sokoto, Nigeria to study the effect of nitrogen fertilizer and inter-row spacing on chemical compositions of Rhodes grass. A factorial combination of five fertilizer levels (0, 100, 120, 140 and 160 kgNha-1) and three inter row spacing (30, 50 and 70 cm) were used, making (15) treatments combinations, which were laid out in a RCBD replicated four times. The data obtained was subjected to analysis of variance (ANOVA), using CRD with two repetitions, Least Significant difference (LSD was used for the separation of means. The sample for each treatment was analyzed for chemical composition using A.O.A.C procedure (CP) was determined by Kjeldahl method, Ash was determined by burning the herbage sample in a furnace at 550-650°C for 3 hours. Ether extract (EE) was estimated by using Sohlex extraction method, crude fibre (CF) was determined by sequential acid and alkali extractions from the residue obtained after fat extraction. Nitrogen free extract (NFE) was calculated as residual component of the feed dry matter; the result revealed that, application of 160 kgNha-1 consistently recorded higher values (P

Parthenium hysterophorus is an alien invasive weed infesting grasslands in many countries around the world, including Australia. Previous studies have identified several native and introduced fodder species that can suppress biomass production of parthenium weed. In the present study, a total of 11 fodder species were tested for their ability to suppress growth of parthenium weed, of which, seven were sown at Injune and Mungallala in Queensland, Australia, with some species tested at both locations. At the Injune site, four introduced pasture species, i.e. Digitaria milanjiana, Clitoria ternatea, Cenchrus ciliaris and Chamaecrista rotundifolia significantly reduced shoot dry biomass of parthenium weed by 60 to 80%, while two native species, i.e. Bothriochloa macra and Eragrostis leptostachya had no significant effect. Cenchrus ciliaris and C. ternatea produced large amounts of dry fodder biomass, i.e. 404 and 360 g m(-2), respectively. At the Mungallala site, three introduced species, i.e. D. milanjiana, Chloris gayana and C. rotundifolia and one native species, i.e. Dichanthium sericeum significantly reduced dry biomass of parthenium weed by >80%, producing sizeable fodder biomass (260 to 400 g m(-2)). The findings support the view that certain introduced and native pasture plant species can suppress the growth of parthenium weed at two contrasting locations and therefore show promise as potential tool for improved management of parthenium weed.

Lipid metabolism, carcass characteristics and fatty acid (FA) composition of the Longissimus dorsi (loin eye) muscle were evaluated in tropical crossbred steers backgrounded on Desmanthus spp. (desmanthus) with or without feedlot finishing. It was hypothesized that steers backgrounded on isonitrogenous diets augmented with incremental proportions of desmanthus will produce carcasses with similar characteristics and FA composition. Forty-eight Brahman, Charbray and Droughtmaster crossbred beef steers were backgrounded for 140 days on Rhodes grass (Chloris gayana) hay augmented with 0, 15, 30 or 45 percent desmanthus on dry matter basis. Lucerne (Medicago sativa) hay was added to the 0, 15 and 30 percent desmanthus diets to ensure that they were isonitrogenous with the 45 percent desmanthus diet. After backgrounding, the two heaviest steers in each pen were slaughtered and the rest were finished in the feedlot for 95 days before slaughter. Muscle biopsy samples were taken at the beginning and end of the backgrounding phase. Carcasses were sampled at slaughter for intramuscular fat (IMF) content, fat melting point (FMP) and FA composition analyses. Increasing the proportion of desmanthus in the diet led to a linear increase in docosanoic acid (p = 0.04) and omega-6/omega-3 polyunsaturated FA ratio (n-6/n-3 PUFA; p = 0.01), while docosahexaenoic acid decreased linearly (p = 0.01). Feedlot finishing increased hot carcass weight, subcutaneous fat depth at the P8 site and dressing percentage (p ≤ 0.04). The n-6/n-3 PUFA ratio was within the recommended < 5 for human diets. IMF was within the consumer-preferred ≥3% level for palatability. The hypothesis that steers backgrounded on isonitrogenous diets augmented with incremental proportions of desmanthus will produce similar carcass characteristics and FA composition was accepted. These findings indicate that a combination of tropical beef cattle backgrounding on desmanthus augmented forage and short-term feedlot finishing produces healthy and highly palatable meat.

Rhodes grass (Chloris gayana Kunth) is one of the most important forage grasses used throughout the tropical and subtropical regions of the world. Enhancing the conservation and use of genetic resources requires the development of knowledge and understanding about the existing global diversity of the species. In this study, 104 Rhodes grass accessions, held in trust in the ILRI forage genebank, were characterized using DArTSeq markers to evaluate the genetic diversity and population structure, and to develop representative subsets, of the collection. The genotyping produced 193,988 SNP and 142,522 SilicoDArT markers with an average polymorphic information content of 0.18 and 0.26, respectively. Hierarchical clustering using selected informative markers showed the presence of two and three main clusters using SNP and SilicoDArT markers, respectively, with a cophenetic correction coefficient of 82%. Bayesian population structure analysis also showed the presence of two main subpopulations using both marker types indicating the existence of significant genetic variation in the collection. A representative subset, containing 21 accessions from diverse origins, was developed using the SNP markers. In general, the results revealed substantial genetic diversity in the Rhodes grass collection, and the generated molecular information, together with the developed subset, should help enhance the management, use and improvement of Rhodes grass germplasm in the future.

The hypothesis tested was that tropical steers supplemented with the Desmanthus legume and lucerne, a widely characterized temperate legume of high nutritive value, would elicit similar responses in plasma metabolite profiles, productive performance, nitrogen retention, and volatile fatty acids (VFA). The tannin-binding compound, polyethylene glycol-4000 (PEG), was added to the diets (160 g/kg Desmanthus dry matter) with the objective of further exploring nitrogen (N) utilization in the animals supplemented with Desmanthus relative to lucerne. From February to June 2020, sixteen yearling Brangus steers (average liveweight of 232 ± 6 kg) were fed a background diet of Rhodes grass (Chloris gayana) hay for 28 days, before introducing three Desmanthus cultivars (Desmanthus virgatus cv. JCU2, D. bicornutus cv. JCU4, D. leptophyllus cv. JCU7) and lucerne (Medicago sativa) at 30% dry matter intake (DMI). Relative to the backgrounding period, all supplemented steers exhibited similar growth performance. Steers supplemented with Desmanthus recorded a lower DMI and animal growth performance, but higher fecal N concentration than animals supplemented with lucerne. Among the three Desmanthus cultivars, there were no significant differences in N concentrations, VFA, and plasma metabolite profiles. The addition of PEG induced higher rumen iso-acid concentrations and fecal N excretion. However, feeding Desmanthus spp. to tropical Bos indicus steers could be a valuable means of increasing N utilization, which is attributable to the presence of tannins, and, consequently, improve animal productive performance. Since supplementation with lucerne resulted in higher liveweight, daily liveweight gains, and overall animal performance than supplementing with Desmanthus, the tested hypothesis that both supplements will elicit similar animal performance does not hold and must be rejected. Further in vivo investigation is needed to better understand the impact of tannins in Desmanthus on N utilization.

Fil: Ruolo, María Soledad. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro Regional Córdoba. Estación Experimental Agropecuaria Manfredi (EEA Manfredi). Córdoba, Argentina. Fil: Pérez, Héctor Eduardo. Instituto Nacional de Tecnología Agropecuaria (INTA). Centro Regional Córdoba. Estación Experimental Agropecuaria Manfredi (EEA Manfredi). Córdoba, Argentina. Fil: Rodríguez, Adriana Mabel. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Forrajicultura. Buenos Aires, Argentina. Subtropical pastures are an important alternative to increase forage yields to fulfil cattle nutritional requirements.\nDespite the increasing expansion of these pastures in the semiarid subtropical region of Argentina, there is very little information about their responses to grazing management.\nThe aim of this study was to evaluate the effect of different defoliation regimes on morphogenesis, sward structure and leaf area index of one of the most expanded forage species in this region, Chloris gayana Kunth.\nA combination of two defoliation frequencies (300 and 500 GDD) and two defoliation intensities (1 and 3 green stubble leaves) was compared by a controlled experiment that comprised 1,500 GDD.\nDefoliation frequency significantly affected leaf elongation rate (LER) and leaf area index (LAI).\nUnder the high defoliation frequency, LER and LAI resulted almost half than under low defoliation frequency (0.34 more or less 0.08 vs. 0.67 more or less 0.08 mm·tiller−1·GDD−1; 8.31 more or less 2.27 m2/m2 vs. 13.27 ± 1.59 m2/m2, at 300 or 500 GDD respectively), regardless of the intensity.\nDefoliation frequency or intensity did not affect leaf appearance rate, leaf lifespan, leaf size, number of green leaves per tiller nor tiller density at the end of the experiment.\nWe conclude that to maintain high LER and LAI in Chloris gayana Kunth cv. Épica INTA - Pemán pastures, defoliation frequency could be of 500 GDD.\nSince leaf lifespan was 415 ± 110 GDD, under this defoliation frequency, a maximum accumulation of green leaf tissues with very little dead tissues may be achieved.\n grafs.

Soil salinity is a growing problem on many irrigated parts of arid and semi-arid areas of Ethiopia. Utilization of improved salt-tolerant forage grasses help farmers to maximize production and reclaim saline soil. A study was conducted at Werer Agricultural Research Center (WARC) from 2012 to 2014 to evaluate performance of four forage grass species of salinity tolerance, ameliorative effect and biomass production. The result showed that dry matter yield obtained under saline soil was higher in Cinchrus ciliaris (37 ton/ha/year) followed by Chloris gayana (36 ton/ha/year), while the smallest was recorded from Sorghum sudanese (27 ton/ha/year). After exposing for salt stress, C. gayana and C. ciliaris dry matter production relative to normal soil only decrease by 15 and 9%, respectively. While, Panicum antidotale and S. sudanese dry matter reduction was Severe, by 53 and 45%, respectively. Reduction in electrical conductivity (ECe) varied between 52.60 and 74.81% in the upper 0 to 30 cm soil layer and 54.76 to 79.63% in the lower 30 to 60 cm. The highest reduction percentage of salinity under surface (74.81%) and sub-surface (79.63%) layer soil occurred under C. gayana grass. C. ciliaris, P. antidotale and S. sudanese cause the reduction at surface soil layer ECe by 70.55, 66.42 and 54.76%, respectively. The same trend was observed for reduction of ESP and pHe as a result of growing of grass species. Generally, C. gayana and C. ciliaris have excellent potential for its high salinity stress tolerance, biomass production and ameliorative effect on soil properties. Key words: Salinity, amelioration, forage grasses, biomass yield.

The mature larva and puparium of Atherigona hyalinipennis van Emden are described, a parasite and further distributional data recorded and notes given on biology.

The edible Ruspolia differens (Orthoptera: Tettigoniidae) is a widely-consumed insect in East Africa but surprisingly little is known of its host plant use in the field. We studied host plants used by non-swarming R. differens for 15 months, in central Uganda. In particular, we assessed the use of host plant species with respect to host cover in the field and host parts used by R. differens, also recording their sex, developmental stages, and colour morph. Ruspolia differens were found on 19 grass and two sedge species and they were observed predominantly (99% of 20,915 observations) on seven grasses (namely, Panicum maximum, Brachiaria ruziziensis, Chloris gayana, Hyparrhenia rufa, Cynodon dactylon, Sporobolus pyramidalis, and Pennisetum purpureum). Ruspolia differens was most frequently observed on the most common grass of each study site but P. maximum, and S. pyramidalis were used more frequently than expected from their cover in the field. Furthermore, R. differens were observed predominantly on inflorescences (97% of feeding observations) and much less frequently on the leaves (3.0%), stems (0.1%), and inflorescence stalks (0.1%) of grasses and sedges. Host use was not independent of sex, developmental stage, or colour morph. Panicum maximum was the preferred host of the youngest nymphs of R. differens. Overall, our findings indicate that a continuous supply of diverse grass resources with inflorescences is necessary for the management and conservation of wild populations of R. differens.

Chloris gayana is a warm-season grass, often cultivated in areas where soil salinity is a major constraint for forage production. Five cultivars (2 unselected populations and 3 synthetic varieties) were evaluated through agronomic traits as well as Inter Simple Sequence Repeats (ISSRs) and Sequence-related Amplified Polymorphism (SRAP) molecular markers. The consensus between both agronomic and molecular data sets was high (>99%) suggesting that both systems provided similar estimates of genetic relationships. The analysis revealed that synthetic varieties, Finecut, Topcut and Santana, were the most genetically different cultivars, whereas the unselected populations, Pioneer and Katambora, were closely related. Responses to salinity stress during germination and early vegetative growth stages were evaluated in only the synthetic varieties. The results showed that Finecut and Santana were able to germinate in the same proportion as controls even at concentrations of 200 mM NaCl. Under hydroponic conditions, Santana attained approximately 20% higher total dry weight than the other 2 varieties and the longest roots. Finecut presented the highest root dry weight. These results suggested that Santana and Finecut showed high salinity tolerance at germination and early vegetative growth stages, both crucial phases when seeking a successful pasture establishment, particularly in saline environments. Further studies in the field are needed to determine if these hydroponic results are reproduced under field conditions.

Chloris gayana Kunth, Révis. Gramin. 1: 89 (1829). Distribution: Macaronesia, Trop. & S. Africa, Arabian Pen. Specimens: MOSHI Engare Rongai stream, Greenway, P.J. 6741 (K); Kwasadala, Hemp, A. 3429 (NHT, UBT); Marangu, Ndakidemi, B. 15 (NHT); Mengeni, Hemp, A. 2670 (UBT); Old Moshi, Hemp, A. 2319 (NHT, UBT); Sanya, Brooks, A.C. 3 (K); Sanya River, Haarer, A.E. 1097 (K); Simba Farm, Grimshaw, J.M. 94566 (K)., Published as part of Prunera-Olivé, Joan, Vorontsova, Maria S., Williams, Emma V., Mollel, Neduvoto P. & Hemp, Andreas, 2021, Checklist of Kilimanjaro grasses shows that both plot and herbarium methods are necessary to record diversity, pp. 201-244 in Phytotaxa 501 (2) on page 218, DOI: 10.11646/phytotaxa.501.2.1, http://zenodo.org/record/5424816

Rhodes grass (Chloris gayana Kunth) is one of the most important forage grasses used throughout the tropical and subtropical regions of the world. Enhancing the conservation and use of genetic resources requires the development of knowledge and understanding about the existing global diversity of the species. In this study, 104 Rhodes grass accessions, held in trust in the ILRI forage genebank, were characterized using DArTSeq markers to evaluate the genetic diversity and population structure, and to develop representative subsets, of the collection. The genotyping produced 193,988 SNP and 142,522 SilicoDArT markers with an average polymorphic information content of 0.18 and 0.26, respectively. Hierarchical clustering using selected informative markers showed the presence of two and three main clusters using SNP and SilicoDArT markers, respectively, with a cophenetic correction coefficient of 82 %. Bayesian population structure analysis also showed the presence of two main subpopulations using both marker types indicating the existence of significant genetic variation in the collection. A representative subset, containing 21 accessions from diverse origins, was developed using the SNP markers. In general, the results revealed substantial genetic diversity in the Rhodes grass collection and the generated molecular information, together with the developed subset, should help enhance the management, use and improvement of Rhodes grass germplasm in the future.

Resumen Introducción. Los forrajes de pastoreo son la principal fuente alimenticia del ganado. La variación climática reta a los productores a mantener una oferta constante de alimento, por lo que es necesario explorar otras alternativas forrajeras. Objetivo. Evaluar el comportamiento de veinte genotipos de Chloris gayana para explotaciones ganaderas. Materiales y métodos. El trabajo se desarrolló en el Centro de Investigación El Nus de la Corporación Colombiana de Investigación Agropecuaria (AGROSAVIA), San José del Nus, Antioquia, Colombia. Se empleó un diseño de bloques completos al azar, tres repeticiones y veinte tratamientos (genotipos Chloris gayana). En el análisis se utilizó un modelo mixto medidas repetidas en el tiempo, con el procedimiento GLIMMIX, cuyo efecto tiempo lo representó edad de corte. Las frecuencias de corte utilizadas fueron 21, 28, 35 y 42 días, entre agosto 2017 y octubre 2019 en época de baja y alta precipitación. Se evaluó vigor, cobertura de la especie, altura de planta, incidencia de plagas y patógenos, floración, rendimiento de materia seca (MS), proteína cruda (PC), fibra en detergente neutro y ácido (FDN, FDA), lignina (LIG), digestibilidad (DIG), hemicelulosa (HEM) y energía neta de lactancia (ENL). Resultados. Los caracteres que aportaron mayor variabilidad fueron MS, PC, FDN, FDA y DIG, se observó una asociación entre DIG, HEM y ENL. Se presentaron diferencias entre épocas y entre genotipos para la mayoría de las variables, a excepción de PC. La lignina fue la única que presentó diferencia en la triple interacción (genotipo*época*días de corte). La interacción genotipo*época mostró diferencias para FDA y LIG. El genotipo 13103 obtuvo el mayor rendimiento de MS (3032,2 kg MS ha-1). La B. decumbens presentó el menor contenido de FDA y LIG, pero la mayor digestibilidad. Conclusiones. Los genotipos experimenales presentaron características de productividad y nutricionales similares e incluso mejores que los testigos. Abstract Introduction. Grazing forages are the main feed source for livestock. Climatic variation challenges producers to maintain a constant supply of food, so it is necessary to explore other forage alternatives. Objective. To evaluate the performance of twenty genotypes of Chloris gayana for livestock farms. Materials and methods. The work was carried out at the El Nus Research Center of the Corporacion Colombiana de Investigacion Agropecuaria (AGROSAVIA), San José del Nus, Antioquia, Colombia. A randomized complete block design, three repetitions, and twenty treatments (Chloris gayana genotypes) was used. The analysis used a mixed model repeated measures over time, with the GLIMMIX procedure, whose time effect was represented by cut-off age. The cutting frequencies used were 21, 28, 35, and 42 days, between August 2017 and October 2019 in low and high rainfall seasons. Vigor, species cover, plant height, pests, and pathogen incidence, flowering, dry matter yield (MS), crude protein (PC), fiber in neutral and acid detergent (FDN, FDA), lignin (LIG), digestibility (DIG), hemicellulose (HEM), and net lactation energy (ENL) were evaluated. Results. The characters that contributed the greatest variability corresponded to MS, PC, FDN, FDA, and DIG; an association was observed between DIG, HEM, and ENL. There were differences between seasons and between genotypes for most of the variables, except for PC. Lignin was the only variable that showed a difference in the triple interaction (genotype*season*cutting days). The genotype*season interaction showed differences for FDA and LIG. Genotype 13103 obtained the highest MS yield (3032.2 kg DM ha-1). B. decumbens had the lowest content of FDA and LIG; but the highest of digestibility. Conclusions. The experimental genotypes presented similar or even better productivity and nutritional characteristics than the controls.

Grazing is one of the most important land management activities worldwide, and cases of overgrazing increase erosion, land degradation, and plant invasion. The objective of this study was to assess the effect on individual species and species composition in response to groups of plants removals or grass seeding after four years of vegetation transformation in a microphyllous desert shrubland excluded from cattle grazing. Nine treatments involved (1) clearing of vegetation and seeding of Bouteloua curtipendula (BOCU), a native grass, (2) clearing and seeding of Chloris gayana (CHGA), an introduce grass from Africa, (3) clearing except for grasses (GRA), (4) clearing except for grasses and fodder shrubs (GRA-SHR), (5) free grazing by cattle (GRAZ), (6) clearing except fodder shrubs (SHR), (7) no modification (CON), (8) clearing of all plants (BARE), and (9) clearing except plants not eaten by cattle (UND). Treatments were replicated five times each in 10 m × 10 m experimental plots. Plots were surveyed for density, cover of all plants, and standing forage. Total plant cover was higher in CON and UND than the other treatments. Except for BOCU, where forage production was the highest, forage production ha−1 was low among all other treatments. Plant density was highest in SHR and lowest in CON. Results after four years of transformation indicate that seeded Chloris gayana failed to become established, but seeding of Bouteloua curtipendula was able to persist, and had the greatest influence on the vegetation restoration, which is what we consider the most appropriate restoration treatment.