The Compensatory Tillering in the Forage Grass Hordeum brevisubulatum After Simulated Grazing of Different Severity

Urochloa (including Brachiaria, Megathyrus and some Panicum) tropical grasses are native to Africa and are now, after selection and breeding, planted worldwide, particularly in South America, as important forages with huge potential for further sustainable improvement and conservation of grasslands. We aimed to develop an optimized approach to determine ploidy of germplasm collection of this tropical forage grass group using dried leaf material, including approaches to collect, dry and preserve plant samples for flow cytometry analysis. Our methods enable robust identification of ploidy levels (coefficient of variation of G0/G1 peaks, CV, typically <5%). Ploidy of some 348 forage grass accessions (ploidy range from 2x to 9x), from international genetic resource collections, showing variation in basic chromosome numbers and reproduction modes (apomixis and sexual), were determined using our defined standard protocol. Two major Urochloa agamic complexes are used in the current breeding programs at CIAT and EMBRAPA: the ’brizantha’ and ’humidicola’ agamic complexes are variable, with multiple ploidy levels. Some U. brizantha accessions have odd level of ploidy (5x), and the relative differences in fluorescence values of the peak positions between adjacent cytotypes is reduced, thus more precise examination of this species is required. Ploidy measurement of U. humidicola revealed aneuploidy.

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Fruit Tree-Based Agroforestry Systems for Smallholder Farmers in Northwest Vietnam—A Quantitative and Qualitative Assessment

Land ◽

10.3390/land9110451 ◽

2020 ◽

Vol 9 (11) ◽

pp. 451

Author(s):

Van Hung Do ◽

Nguyen La ◽

Rachmat Mulia ◽

Göran Bergkvist ◽

A. Sigrun Dahlin ◽

...

Keyword(s):

Management Practices ◽

Smallholder Farmers ◽

Knowledge Exchange ◽

Fruit Trees ◽

Agroforestry Systems ◽

Fruit Tree ◽

Rapid Expansion ◽

Qualitative Assessment ◽

Forage Grass ◽

High Investment

Rapid expansion of unsustainable farming practices in upland areas of Southeast Asia threatens food security and the environment. This study assessed alternative agroforestry systems for sustainable land management and livelihood improvement in northwest Vietnam. The performance of fruit tree-based agroforestry was compared with that of sole cropping, and farmers’ perspectives on agroforestry were documented. After seven years, longan (Dimocarpus longan Lour.)-maize-forage grass and son tra (Docynia indica (Wall.) Decne)-forage grass systems had generated 2.4- and 3.5-fold higher average annual income than sole maize and sole son tra, respectively. Sole longan gave no net profit, due to high investment costs. After some years, competition developed between the crop, grass, and tree components, e.g., for nitrogen, and the farmers interviewed reported a need to adapt management practices to optimise spacing and pruning. They also reported that agroforestry enhanced ecosystem services by controlling surface runoff and erosion, increasing soil fertility and improving resilience to extreme weather. Thus, agroforestry practices with fruit trees can be more profitable than sole-crop cultivation within a few years. Integration of seasonal and fast-growing perennial plants (e.g., grass) is essential to ensure quick returns. Wider adoption needs initial incentives or loans, knowledge exchange, and market links.

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Effects of selenium (Se) application and arbuscular mycorrhizal (AMF) inoculation on soybean (Glycine max) and forage grass (Urochloa decumbens) development in oxisol

Australian Journal of Crop Science ◽

10.21475/ajcs.19.13.03.p1245 ◽

2019 ◽

Vol 13 ((03) 2019) ◽

pp. 380-385 ◽

Cited By ~ 2

Author(s):

Soraya Marx Bamberg ◽

Silvio Junio Ramos ◽

Marco Aurelio Carbone Carneiro ◽

José Oswaldo Siqueira

Keyword(s):

Mycorrhizal Fungi ◽

Arbuscular Mycorrhizal ◽

Fold Increase ◽

Tropical Soils ◽

Fertilizer Application ◽

Growth And Yield ◽

Forage Grass ◽

Urochloa Decumbens ◽

Soybean Plants ◽

Amf Inoculation

Fertilizer application can enhance the nutritional value of plants, such effects being influenced by the presence of arbuscular mycorrhizal fungi (AMF). Nutrients × AMF interactions are well-known for variety of elements but very little has been addressed on biofortification of selenium (Se) in plants grown in tropical soils. The purpose of this study was to evaluate the effect of Se application and AMF inoculation on growth and micronutrient contents on soybean plants as forage grass. The experiments were conducted in a completely randomized factorial design with five Se doses (0.0, 0.5, 1.0, 2.0 and 3.0 mg kg-1 for soybean plants, and 0.0, 0.5, 1.0, 3.0 and 6.0 mg kg-1 for forage plants), with and without AMF inoculation in three replicates. The results showed that soil Se had only slight effect on soybean growth but it caused a two-fold increase on grain yield. However, the growth of forage grass was enhanced by Se application when AMF was present. The AMF inoculation reduced benefit for soybean growth and yield but marked positive effect on forage grass at high doses of Se. Selenium contents in both plants were increased by its application in soil, being such effect proportional to soil applied doses. Selenium application and AMF inoculation had marked effects on micronutrients contents in both soybean plants and forage grass and they may contribute to Se and micronutrient biofortification.

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Use of tall fescue EST-SSR markers in phylogenetic analysis of cool-season forage grasses

Genome ◽

10.1139/g05-029 ◽

2005 ◽

Vol 48 (4) ◽

pp. 637-647 ◽

Cited By ~ 64

Author(s):

M A. Rouf Mian ◽

Malay C Saha ◽

Andrew A Hopkins ◽

Zeng-Yu Wang

Keyword(s):

Phylogenetic Analysis ◽

Ssr Markers ◽

Tall Fescue ◽

Related Species ◽

Grass Species ◽

Forage Grass ◽

Forage Grasses ◽

Cool Season ◽

Phylogenetic Relations ◽

Wide Range

Microsatellites or simple sequence repeats (SSRs) are highly useful molecular markers for plant improvement. Expressed sequence tag (EST)-SSR markers have a higher rate of transferability across species than genomic SSR markers and are thus well suited for application in cross-species phylogenetic studies. Our objectives were to examine the amplification of tall fescue EST-SSR markers in 12 grass species representing 8 genera of 4 tribes from 2 subfamilies of Poaceae and the applicability of these markers for phylogenetic analysis of grass species. About 43% of the 145 EST-SSR primer pairs produced PCR bands in all 12 grass species and had high levels of polymorphism in all forage grasses studied. Thus, these markers will be useful in a variety of forage grass species, including the ones tested in this study. SSR marker data were useful in grouping genotypes within each species. Lolium temulentum, a potential model species for cool-season forage grasses, showed a close relation with the major Festuca–Lolium species in the study. Tall wheatgrass was found to be closely related to hexaploid wheat, thereby confirming the known taxonomic relations between these species. While clustering of closely related species was found, the effectiveness of such data in evaluating distantly related species needs further investigations. The phylogenetic trees based on DNA sequences of selected SSR bands were in agreement with the phylogenetic relations based on length polymorphism of SSRs markers. Tall fescue EST-SSR markers depicted phylogenetic relations among a wide range of cool-season forage grass species and thus are an important resource for researchers working with such grass species.Key words: phylogeny, EST-SSR, forage grasses, tall fescue.

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The response of pygmy bluetongue lizards to simulated grazing in the field during three drought years

Wildlife Research ◽

10.1071/wr12086 ◽

2012 ◽

Vol 39 (6) ◽

pp. 540 ◽

Cited By ~ 11

Author(s):

Melissa Pettigrew ◽

C. Michael Bull

Keyword(s):

Prey Availability ◽

Careful Consideration ◽

Grazing Management ◽

Control Treatment ◽

Ground Vegetation ◽

Control Group ◽

Drought Period ◽

Before And After ◽

Simulated Grazing ◽

Complex Relationships

Context Grazing by domestic stock can directly influence and shape the functions of an ecosystem. Most remaining remnant native grasslands in Australia are under some form of grazing management, with some possible adverse impacts for endemic grassland biota. For the endangered pygmy bluetongue lizard (Tiliqua adelaidensis), grazing of its remnant native grassland habitat has been seen as a potential conservation threat. Aim We aimed to investigate whether lizards altered their basking and foraging behaviour as a response to simulated grazing of the grassland habitat surrounding their burrows. Methods We used field manipulations over 3 years event by manually removing above-ground vegetation in 1 m2 around occupied lizard burrows, to simulate intense grazing events. We video-recorded lizard responses to these manipulations. We filmed lizards before and after the simulated grazing event and monitored basking and foraging response. We also simultaneously filmed a control group of lizards that were not exposed to a simulated grazing event. Key results Although overall time spent basking did not differ between treatment and control groups, the lizards spent more of their basking time completely emerged (bold basking) in the grazing treatment, suggesting they changed behaviour after simulated grazing. Perhaps they were more confident of evading predators that they could more clearly see approaching. In one season lizards made more attempts to catch prey in the grazed treatment than in a control treatment following the treatment, suggesting that grazing might enhance visibility for the ambush predation method that these lizards use. Conclusions The results suggest that grazing may produce some benefits for lizards already established in burrows. This contrasts with some previous results and suggests that management of grazing regimes requires careful consideration of the conditions currently prevalent. In this case, the study was conducted during a drought period, and different results might have emerged in higher rainfall years. Implications Grazing management for lizard conservation requires detailed understanding of the complex relationships among lizard behaviour, vegetation cover and invertebrate prey availability.

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