Tropical Grasslands-Forrajes Tropicales最新文献

{"title":"Evaluation of ten perennial forage grasses for biomass and nutritional quality","authors":"Mulisa Faji, Gezahagn Kebede, Fekede Feyissa, K. Mohammed, Muluneh Minta, S. Mengistu, Aschelew Tsegahun","doi":"10.17138/tgft(9)292-299","DOIUrl":"https://doi.org/10.17138/tgft(9)292-299","url":null,"abstract":"A study was carried out to evaluate 10 perennial forage grass accessions from 4 species for herbage dry matter yield and nutritional quality at Holetta Agricultural Research Center. The evaluated grasses species and varieties were one Desho grass (Pennisetum) variety Kulumsa, four Urochloa decumbens (ILRI-14721, ILRI-14720, ILRI-13205 and ILRI-10871), three Urochloa ruziziensis (ILRI-14813, ILRI-14774 and ILRI-13332) and two Setaria sphacelata (ILRI-143 and ILRI-6543) accessions. Plant height and forage dry matter yield were significantly affected by accession over years, during the establishment and production phases. Combined analysis indicated that the tested accessions varied significantly for plant height with the Setaria accessions taller than the other tested species. Combined data analysis revealed that forage dry matter yield significantly varied according to species and Desho grass (variety Kulumsa) was higher in dry matter yield than the other grasses tested. Fiber contents (NDF, ADF and ADL) were significantly influenced by accession. Crude protein yield differed among the accessions and Desho grass had higher crude protein, followed by U. decumbens (accession ILRI-13205), U. decumbens (accession ILRI-14721) and S. sphacelata (accession ILRI-6543). Based on dry matter yield and crude protein U. decumbens (accession ILRI-13205), U. ruziziensis (accession ILRI-13332), S. sphacelata (accession 6543) and Desho grass (var. Kulumsa) are recommended as alternative forage grasses for the study area and similar agro-ecologies. ","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42536157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"What drives the adoption of fodder innovation(s) in a smallholder dairy production system? Evidence from a cross-sectional study of dairy farmers in India","authors":"D. Thirunavukkarasu, N. Narmatha, S. Alagudurai","doi":"10.17138/tgft(9)371-375","DOIUrl":"https://doi.org/10.17138/tgft(9)371-375","url":null,"abstract":"The study in India involving 384 households found that 42.7% of dairy farmers adopted new forage varieties when varieties were released. The farmer’s resources, their caste, access to markets for milk and price received for milk had positive effects on the decision to adopt. Management of farms by women had negative effects on the adoption decision. Increased forage yield and ease of propagation and establishment were important reasons for adoption of varieties, e.g. the relative advantage of pearl millet × Napier grass (Cenchrus americanus × C. purpureus) vs. hedge lucerne (Desmanthus virgatus). Thus, researchers need to address these issues when developing new germplasm, if farmers are to readily adopt new varieties, especially in the case of resource-poor farmers.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46191789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quality properties of sunn hemp (Crotalaria juncea L.) and maize (Zea mays L.) silages","authors":"G. D. Topcu, Ş. Özkan","doi":"10.17138/tgft(9)315-320","DOIUrl":"https://doi.org/10.17138/tgft(9)315-320","url":null,"abstract":"Maize is an ideal forage crop for ensilage because of its high levels of fermentable carbohydrates, although it is low in protein. Sunn hemp is a legume with a high crude protein content with potential to be used in combination with maize to provide a silage with a higher protein content. Different percentages of sunn hemp-maize mixtures of 80-20, 60-40, 40-60 and 20-80 respectively were compared to silages of sole maize and sunn hemp. In the laboratory study, DLG classifications (color, smell, structure, total score and quality class), silage loss (%), silage pH, dry matter content, flieg score, crude protein content, crude ash content, NDF, ADF, metabolic energy (MJ kg-1 DM), dry matter intake, percent digestible dry matter and relative feed value were determined at the end of 60 days ensilage. The crude protein contents of silages increased as the sunn hemp ratio in the mixtures increased. In addition, pure sunn hemp silage and mixtures, especially 80% sunn hemp mixed with 20% maize, were found suitable for silage and it was concluded that sunn hemp and sunn hemp-maize silage mixtures could be used in animal husbandry.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46244849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clearing confusion in Stylosanthes taxonomy. 3. S. hamata sensu stricto vs. S. hamata sensu lato","authors":"B. G. Cook, R. Schultze-Kraft","doi":"10.17138/tgft(9)348-358","DOIUrl":"https://doi.org/10.17138/tgft(9)348-358","url":null,"abstract":"Stylosanthes hamata (L.) Taub., a suffruticose leguminous species with spreading prostrate or ascending stems, is widely distributed in the Caribbean region. It was originally described as Hedysarum hamatum by Linnaeus and later transferred to Stylosanthes by Taubert. To date, chromosome analysis of accessions of S. hamata originating from the Caribbean islands has revealed all to be diploids (2n=20). An accession of a morphologically similar Stylosanthes species, collected near Maracaibo in Venezuela in 1965 and subsequently misidentified as S. hamata, has found application as sown forage on low fertility soils in the subhumid to dry tropics since its registration as cultivar Verano in Australia in 1975. This morphotype has been shown to be tetraploid, and has been referred to in the literature as “tetraploid S. hamata” or “S. hamata sensu lato”. More recent work has demonstrated that the tetraploid is in fact an allotetraploid with S. hamata sensu stricto and S. humilis Kunth as the putative diploid progenitors. Various authors have recommended that the allotetraploid be treated as a separate species. We support this recommendation and suggest that, based on the information provided in this paper, the new species be described and validly published following examination of a more exhaustive range of specimens.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42921061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genetic diversity and population structure of Heteropogon contortus L. germplasm collected from diverse agro-climatic regions in India and development of a core germplasm set","authors":"A. Roy, D. Malaviya, P. Kaushal, S. K. Mahanta, R. Tewari, R. Chauhan, A. Chandra","doi":"10.17138/tgft(9)359-370","DOIUrl":"https://doi.org/10.17138/tgft(9)359-370","url":null,"abstract":"Heteropogon contortus, an important constituent of major grasslands of India, Australia and many countries in Africa, Asia and the Americas, is important for pasture and grassland productivity. Hence genetic improvement of the grass needs attention. A genetic variability study, including development of a core subset, was carried out by evaluating 235 accessions collected from different agro-ecological zones of India. The study, based on 16 metric and 14 non-metric traits along with 8 nutritional parameters, indicated that considerable genetic variability existed among the germplasm and selection could result in identification of suitable types for target environments. Clustering and subclustering was performed to select 35 accessions to form a core subset. The statistical analysis indicated that the core subset captured almost all the variability present in the entire germplasm. The study will help researchers to focus future studies on this core subset in developing genetic improvement programs.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47334071","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Canopy characteristics of ‘Mavuno’ hybrid brachiariagrass and ‘Marandu’ palisadegrass harvested at different harvest intensities","authors":"L. F. Rodrigues, J. Vendramini, Antonio C. dos Santos, Jose Dubeux Jr., F. R. Miotto, L. F. Sousa, N. Alencar","doi":"10.17138/tgft(9)249-255","DOIUrl":"https://doi.org/10.17138/tgft(9)249-255","url":null,"abstract":"‘Mavuno’ is a newly released brachiariagrass (Urochloa hybrid) cultivar with limited information available in the literature. The objective of this study was to compare forage characteristics of this cultivar and ‘Marandu’ palisadegrass [Urochloa brizantha (Hochst. ex A. Rich.) R.D. Webster cv. Marandu] harvested at 2 different stubble heights during 2 growing seasons (January‒April). The study was conducted in Araguaína, TO, Brazil in 2017 and 2018. Treatments were the factorial arrangement of 2 brachiariagrass cultivars, Mavuno and Marandu, harvested at 2 harvest intensities, 5 and 15 cm stubble height, distributed in a randomized complete block design with 4 replicates. Response variables were canopy height, forage accumulation, proportion of leaf, stem and dead material, and concentration of crude protein (CP) and in vitro digestible organic matter (IVDOM). Mavuno and Marandu did not differ (P>0.05) in forage accumulation (mean = 3,800 kg DM/ha/harvest) and IVDOM concentration (mean = 637 g/kg); however, Mavuno had lower CP concentration (101 vs. 110 g/kg), greater proportion of stems (16 vs. 13%) and less dead material (4 vs. 6%) than Marandu (P<0.05). Harvesting at 5 cm stubble height rather than 15 cm increased herbage accumulation per harvest (4,100 vs. 3,500 kg DM/ha) with decreased proportion of leaves (77 vs. 84%) and CP concentration (101 vs. 115 g/kg) (P<0.05). Our data suggest that Mavuno is a useful addition to the range of brachiaria grass cultivars for sowing in tropical regions and further studies are needed to evaluate the long-term persistence of Mavuno under different management practices in a range of environmental situations. While harvesting at 5 cm stubble height rather than 15 cm increased forage accumulation but reduced CP concentration, regardless of cultivar, longer-term effects on the stability of these pastures with these harvest frequencies and heights are open to question and studies should be continued for longer periods to assess longevity of stands under the 2 management strategies. Applying maintenance fertilizer during the growing season might have prevented the marked decline in dry matter accumulation as the season advanced and this hypothesis should be tested.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":" ","pages":""},"PeriodicalIF":0.7,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45016783","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of timing of nitrogen fertilizer application on responses by tropical grasses","authors":"C. Cabral, A. Motta, A. R. M. Santos, F. J. Gomes, B. Pedreira, C. E. A. Cabral","doi":"10.17138/TGFT(9)182-191","DOIUrl":"https://doi.org/10.17138/TGFT(9)182-191","url":null,"abstract":"Timing of nitrogen (N) fertilizer application can influence grass regrowth, so it is important to identify how tropical grasses respond to delays in applying fertilizer after defoliation. Our objective was to identify the effects of timing of N fertilizer application after harvest on the productive, morphogenic and structural characteristics of 3 tropical grasses: ‘Xaraés’ (Urochloa brizantha [Hochst. ex A. Rich.] Stapf cv. Xaraés), ‘Marandu’ (Urochloa brizantha [Hochst. ex A. Rich.] Stapf cv. Marandu) and ‘Tanzânia’ (Megathyrsus maximus [Jacq.] cv. Tanzânia). The experiments were performed in a greenhouse, in a completely randomized design, with 5 delays in applying N after harvesting (0, 3, 6, 9 and 12 days). Delaying fertilizer application did not affect the forage mass of Xaraés and Marandu palisade grass (7.4 and 7.8 g/pot, respectively). There was a linear decrease in number of leaves per tiller and leaf appearance rate, but tiller population density and phyllochron increased linearly as fertilizer application was delayed. Grass forage mass (12.2‒10.6 g/pot), number of leaves per tiller (3.1‒2.6 leaves/tiller) and forage accumulation rate (0.47 to 0.41 g DM/d) of Tanzânia guinea decreased linearly as N application was delayed, but tiller population density was unaffected (25 tillers/pot). Based on our results, N fertilizer should be applied to Tanzânia guinea grass pastures as soon as possible after harvest and certainly before 3 days, while there is not the same urgency with Xaraés and Marandu where fertilization could be delayed up to 12 days without significant detriment. These suggestions need to be tested in a field study before being recommended widely.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":"8 1","pages":"182-191"},"PeriodicalIF":0.7,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86308824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Producción animal en pasturas de tres leguminosas asociadas con Urochloa decumbens en los Llanos Orientales de Colombia","authors":"Á. R. Castillo, M. Villalobos","doi":"10.17138/TGFT(9)192-205","DOIUrl":"https://doi.org/10.17138/TGFT(9)192-205","url":null,"abstract":"In a loamy clay soil of the Colombian Altillanura, animal production of the legumes Centrosema molle accession CIAT 15160, C. macrocarpum accession CIAT 15799 and Grona heterocarpa subsp. ovalifolia (syn. Desmodium ovalifolium) cv. Maquenque, in association with Urochloa decumbens (syn. Brachiaria decumbens) cv. Decumbens, was evaluated under rotational grazing with zebu Brahman steers. The experiment was established in a native savanna area at the Carimagua Research Center of Agrosavia, in a randomized complete block design with three replications. During three years of grazing, C. molle stood out over the other legumes, due to its good forage production and ability to associate and persist with the grass, reaching 40% in the botanical composition in the first year and 24% in the third year. The highest animal liveweight (LW) gains were achieved with this legume with, on average, 760 g/animal/day in the rainy season and 500 g/animal/day in the dry season. With an average stocking rate equivalent to 800 kg LW/ha, mean annual hectare productivity of the pasture with C. molle reached 600 kg LW compared with an average of about 380 kg/ha/year obtained in the other associations and in the grass-only pasture. It is concluded that C. molle CIAT 15160 is a promising pasture legume for the region and confirming its productivity and persistence at farm level and in association with other grasses seems warranted.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":"6 1","pages":"192-205"},"PeriodicalIF":0.7,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82040225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Root production in a subtropical pasture is mediated by cultivar identity and defoliation severity","authors":"Chris H. Wilson, J. Vendramini, L. Sollenberger, S. Flory","doi":"10.17138/TGFT(9)144-158","DOIUrl":"https://doi.org/10.17138/TGFT(9)144-158","url":null,"abstract":"Grasslands occupy significant land area and account for a large proportion of the global soil carbon stock, yet the direct effects of grazing and genotypic composition on relationships between shoot and root production are poorly resolved. This lack of understanding hinders the development of models for predicting root production in managed grasslands, a critical variable for determining soil carbon stocks. We quantified the effects of season-long defoliation treatments on both shoot and root production across 4 cultivars of a widely planted pasture grass species (Paspalum notatum Flüggé) in a common garden setting in South Florida, USA. We found that infrequently applied (4 weekly) severe defoliation (to 5 cm) substantially enhanced shoot production for all cultivars, while severe defoliation reduced root production across cultivars, regardless of frequency. Overall, there was no significant relationship between shoot and root production. Our results showed that above-ground and below-ground productivity are only weakly coupled, suggesting caution against use of simple above-ground proxies to predict variations in root production in grasslands. More broadly, our results demonstrated that improved modeling and management of grasslands for below-ground ecosystem services, including soil carbon sequestration/stocks, must account for intraspecific genetic variation and responses to defoliation management.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":"108 5 1","pages":"144-158"},"PeriodicalIF":0.7,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89725020","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prospective genetic gain to improve salinity tolerance in a population of Panicum coloratum var. coloratum with two different selection methods","authors":"G. Pittaro, Mauro Lifschitz, Miguel Sánchez, D. Bustos, J. Otondo, M. A. Tomás","doi":"10.17138/TGFT(9)171-181","DOIUrl":"https://doi.org/10.17138/TGFT(9)171-181","url":null,"abstract":"Panicum coloratum var. coloratum is a subtropical grass for potentially increasing forage production in lowly productive environments where cattle-raising activities have been relocated. Heritability was estimated for characters related to salinity tolerance under saline and non-saline conditions to explore the possibility of improving tolerance by selection. From a base germplasm collected in a very harsh environment, heritability and gain after selection were calculated using 2 recombination units: individual and phenotypic family mean (PFM). Heritability estimates were very low for all characters both in saline and non-saline conditions, suggesting a complex genetic control of salinity tolerance, with a high proportion of non-additive genetic effects. Estimates were higher using individual selection than with PFM and expected genetic gains were higher for individual selection. When compared in both saline and non-saline conditions, predicted means were greater than for plants of cv. Klein, the most common cultivar in use. It appears that the analyzed germplasm would be a valuable source of genes to be included in breeding programs to increase salinity tolerance in Panicum coloratum.","PeriodicalId":56049,"journal":{"name":"Tropical Grasslands-Forrajes Tropicales","volume":"57 224 1","pages":"171-181"},"PeriodicalIF":0.7,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83295769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}