Plant Biology Commons^™

Interacting Effects Of Nutrient Availability And Environmental Change On Grassland Plant Communities, George Robert Wheeler

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The availability of nutrients plays an important role in shaping the composition, productivity and diversity of plant communities. Such effects are particularly well documented in grassland ecosystems, where both independent studies and collaborations such as the Nutrient Network consistently show increasing productivity and decreasing diversity with the addition of limiting nutrients. The specifics of this pattern, however, vary widely from site to site, and within a single site, they may shift with changes in environmental conditions and disturbance regimes.

My research at Cedar Creek Ecosystem Science Reserve (Minnesota, USA), documents such a pattern through resampling of a long-term experiment on …

Investigating The Expression Of Growth-Regulating Factor 2 (Grf2) In Arabidopsis Thaliana, Sophia S. Henry

Senior Theses

Arabidopsis thaliana is a model organism that is used in laboratories across the world for the study of cellular and molecular processes in plants. GROWTH-REGULATING FACTOR 2 (GRF2) is a transcription factor that promotes leaf growth in Arabidopsis. It is a member of a family of transcription factors that is conserved across all land plants. Previous studies have characterized GRF2 expression in leaves, but GRF2 expression in floral organs has not been studied as extensively. GRF2 acts redundantly with other members of the GRF transcription factor family during floral development. grf1/2/3/5 quadruple mutants show malformed gynoecia, severe fusions between floral …

Experimental Test Of Reforestation With Maesopsis Eminii Engl. And Millettia Drastica Welw. In The Eco-Climatic Conditions Of Kinshasa In The Drc, Bozele Nyabobola Alphonse, Dande Assikpu Patrick, Belesi Katula Honore, Lubini Ayingweu Constantin

Journal of Bioresource Management

The study focuses on the the experimental test of reforestation with Maesopsis eminii and Millettia drastica in the eco-climatic conditions of Kinshasa, with the aim of assessing the development and growth of the species through germination, and their behaviour in relation to the soil in the conditions of Kinshasa, with a view to proposing advice for responsible afforestation and reforestation. The results show that both species tend to reduce soil acidity. After cultivation, the pHs were 4.49 and 4.69 respectively for soils 1 and 2, compared with 3.98 for soil 0. In addition, Millettia drastica neutralises aluminium in the soil …

Univariate And Multivariate Approaches For Identifying Key Differential Volatile Compounds In Wedelia Trilobata Essential Oils From Four Different Locations, Tuan Ashraf Faiz Tuan Anuar, Suria Ramli, Chamroon Laosinwattana, Kamalrul Azlan Azizan

Makara Journal of Science

Geographical location is an important factor affecting the production of the volatile compounds and corresponding bioactivity of essential oil (EO). The aim of this study was to determine whether the bioactivity of Wedelia trilobata EO varies by geographical location and identify the key volatile compounds involved in bioactivity. A total of 95 volatile compounds reported in W. trilobata EOs obtained from Brazil, India, Malaysia and Thailand were retrieved from the literature, and changes and key differential volatile compounds were identified with univariate and multivariate methods. Results showed that the monoterpene hydrocarbon content of α-phellandrene and α-pinene were higher than that …

Long-Term Soil Change In The Us Great Plains: An Evaluation Of The Haas Soil Archive, Mark A. Liebig, Francisco J. Calderon, Andrea K. Clemensen, Lisa Durso, Jessica L. Duttenhefner, Jed O. Eberly, Jonathan J. Halvorson, Virginia L. Jin, Kyle Mankin, Andrew J. Margenot, Catherine E. Stewart, Scott Van Pelt, Merle F. Vigil

Department of Agronomy and Horticulture: Faculty Publications

Diverse patterns of climate and edaphic factors challenge detection of soil property change in the US Great Plains. Because detectable soil change can take decades, insights into the trajectory of soil properties frequently require long-term site monitoring and, where available, associated soil archives to enable comparisons with initial or baseline states. Unfortunately, few multi-decadal soil change investigations have been conducted in this region. Here, we document effects of dryland cropping on a suite of soil properties by comparing matched historic (1947) and contemporary (2018) soil samples from the Haas Soil Archive at three sites in the US Great Plains: Moccasin, …

Unlocking The Promise Of The ″Miracle Tree: A Review On Therapeutic Applications And Phytochemistry Of Moringa Oleifera L., Ali Zeeshan, Mubashrah Munir, Sehrish Sadia

Journal of Bioresource Management

Moringa oleifera, commonly known as the "miracle tree", has been used for centuries in traditional medicine and has recently garnered interest from the scientific community for its therapeutic potential. This review summarizes the current knowledge on the phytochemistry, nutritional composition, and medicinal properties of different parts of M. oleifera. The leaves, pods, bark, roots, seeds, and flowers contain various essential nutrients like vitamins, minerals, amino acids, antioxidants, and phytochemicals such as flavonoids, glucosinolates, and phenolic acids. These bioactive compounds confer anti-diabetic, anti-cancer, cardioprotective, anti-inflammatory, antimicrobial, immunomodulatory, anti-venom, and wound healing properties. Extracts and isolates from M. oleifera have shown …

Genomes Of Multicellular Algal Sisters To Land Plants Illuminate Signaling Network Evolution, Xuehuan Feng, Jinfang Zheng, Iker Irisarri, Huihui Yu, Bo Zheng, Zahin Ali, Sophie De Vries, Jean Keller, Janine M. R. Fürst-Jansen, Armin Dadras, Jaccoline M. S. Zegers, Tim P. Rieseberg, Amra Dhabalia Ashok, Tatyana Darienko, Maaike J. Bierenbroodspot, Lydia Gramzow, Romy Petroll, Fabian B. Haas, Noe Fernandez-Pozo, Orestis Nousias, Tang Li, Elisabeth Fitzek, W. Scott Grayburn, Nina Rittmeier, Charlotte Permann, Florian Rümpler, John M. Archibald, Günter Theißen, Jeffrey P. Mower, Maike Lorenz16, Henrik Buschmann, Klaus Von Schwartzenberg, Lori Boston, Richard D. Hayes, Chris Daum, Kerrie Barry, Igor V. Grigoriev, Xiyin Wang, Fay-Wei Li, Stefan A. Rensing, Julius Ben Ari, Noa Keren, Assaf Mosquna, Andreas Holzinger, Pierre-Marc Delaux, Chi Zhang, Jinling Huang, Marek Mutwil6,, Jan De Vries, Yanbin Yin

Center for Plant Science Innovation: Faculty Publications

Zygnematophyceae are the algal sisters of land plants. Here we sequenced four genomes of filamentous Zygnematophyceae, including chromosome-scale assemblies for three strains of Zygnema circumcarinatum. We inferred traits in the ancestor of Zygnematophyceae and land plants that might have ushered in the conquest of land by plants: expanded genes for signaling cascades, environmental response, and multicellular growth. Zygnematophyceae and land plants share all the major enzymes for cell wall synthesis and remodifications, and gene gains shaped this toolkit. Co-expression network analyses uncover gene cohorts that unite environmental signaling with multicellular developmental programs. Our data shed light on a molecular …

Silvopastoral Agroforestry In Upland And Lowland Uk Grassland: Tree Growth And Animal Performance, W R. Eason, R Lavender, R O. Clements, C Duller, E Gill, M Hislop

IGC Proceedings (1977-2023)

Trees, individually protected from herbivore damage using plastic shelters, were planted at two densities (100 and 400 stems/ha) into sheepgrazed pasture in upland and lowland UK grassland sites in 1988. Tree and animal performance were compared with conventional forestry (no sheep) and pasture (no tree) systems. Effects on tree growth and survival are highly species and site dependent although some treatment effects did emerge. Tree shelters encouraged rapid early height growth compared to forestry controls although in some cases tree form was also adversely affected. Generally tree performance within agroforestry treatments was better at the higher planting density. Eight years …

Use Of Annual Self-Reseeding Legumes In An Oak Forest In Central Italy, P Talamucci, G Argenti, A Pardini, S Piemontese, N Stagliano

IGC Proceedings (1977-2023)

A trial has been carried out for three years in an oak coppice geometrically thinned out of Mediterranean Central Italy, about the functioning of a pastoral system made by four different resources: native pasture, subterranean clover (Trifolium brachycalycinum Katzn. et Morley) in pure stand, strips thinned out and firebreaks improved with oversown subclover, all grazed by sheep. Subclover increased the forage yield and improved the palatabilty of the pasture and the regularity of grazing; the higher biomass intake by animals reduced the quantity of dried biomass in summer and contributed to keep low either fire hazards or flame diffusion …

The Effects Of Shelterbelts On Adjacent Pastures And Soils In A Temperate Climate, A G. Gillingham, M F. Hawke

IGC Proceedings (1977-2023)

Two trials were conducted to differentiate the direct (exposure) from the indirect (modified soil fertility due to nutrient transfer by grazing animals) effects of farm shelterbelts on associated pasture growth.Soil from close to “unmanaged”shelterbelts with dense shelter to ground level had relatively high potassium (K) levels and, in a glasshouse situation, provided more pasture growth than soil from further distances, or from adjacent to “managed” shelterbelts. Pasture grown in boxes of a common soil implanted at increasing distances from a shelterbelt also produced highest growth rates close to shelter. These results generally explain the pattern of resident pasture growth, except …

Temperate Pasture And Sheep Performance Under Radiata Pine And In Open Pasture, K M. Pollock, R J. Lucas, D B. Pownall, S E. Thomson

IGC Proceedings (1977-2023)

Forage production from years 4 to 6 of an agroforestry system at 400-600 trees per ha and pasture alone were compared for a temperate sub-humid environment. Forage production was best for lucerne pasture followed by phalaris/clover and cocksfoot/clover, and least for ryegrass/clover and the ryegrass only pastures. Total pasture production in the agroforest relative to the open pasture was from 10% more for phalaris to 20% less for lucerne. Sheep carrying capacity over all pastures was 14.6 sheep/ha in the open and 11.8 sheep/ha in the agroforest and varied by ±15% according to the pasture types.

Grazing Management Of Tagasaste (Chamaecytisus Proliferus) For Sheep And Cattle Production In Southern Australia, N J. Edwards, G M. Allen, D M. Mcneill, C M. Oldham

IGC Proceedings (1977-2023)

Direct grazing of hedgerows of tagasaste (Chamaecytisus proliferus) by sheep or cattle appear to be very robust systems. Tagasaste persists under a continuous grazing regime with cattle such that plant regrowth maintained between 5 and 10 cm in length produces in excess of 215 kg of animal liveweight/ha/year. This level of production is also sustained within a rotational grazing regime. Under both grazing systems cattle production within a year is highly seasonal, with liveweight gains from young cattle peaking at 1.0-1.5 kg/head/day in winter and spring, but dropping to maintenance only by late summer-autumn. Sheep, like cattle, can …

Shrub Palatability To Rusa Deer (Cervus Timorensis Russa) In New Caledonia, C Corniaux, S Le Bel, J M. Sarrailh

IGC Proceedings (1977-2023)

The objective of this study was to determine a palatability scale of five shrub legumes to rusa deer during the dry season in New Caledonia. Acacia ampliceps and Samanea saman remain low in acceptability. Gliricidia sepium is more palatable but quite less than Leucaena leucocephala (native cultivar) and Calliandra calothyrsus (San Ramon). Therefore, since the regression of Leucaena leucocephala population, Calliandra calothyrsus could be very promising to replace it in the deer diet. On the other hand, Acacia ampliceps seems to be the most interesting shrub legume to plant in the west coast, where soil erosion, due to successive droughts …

Soil Nutrient Redistribution Pattern About The Tree In A Silvopastoral System, L C. Nwaigbo, H G. Miller, A R. Sibbald, G Hudson

IGC Proceedings (1977-2023)

The objective of this paper is to report the effect of animal-tree interactions on soil nutrient redistribution pattern in a grazed silvopastoral experiment site at Glensaugh, in NE Scotland. Scots pine (Pinus sylvestris L) tree species were planted in square lattice arrangements at 5 m x 5 m, spacing (400 stems/ha) on plots replicated over three blocks in Randomized Complete Block design on a predominantly rye grass (Lolium perenne L) pasture which was grazed by sheep yearly from April to October. Included in the design were grazed pasture plots without trees (Control). Soil samples were collected from around …

Trees For Shelter: The Implications In Agroforestry System, L C. Nwaigbo, A R. Sibbald, G Hudson

IGC Proceedings (1977-2023)

The objective of this study was to determine the horizontal and vertical variations in soil penetration resistance (PR) observed at tree-scale in silvopastoral plots that were grazed by sheep with and without trees. Sycamore trees (Acer pseudoplatanus L) were planted in the spring of 1988 at 10 m x 10 m spacing (100 stems/ha) at Glensaugh NE of Scotland on plots replicated over three blocks in Randomized Complete Block design on a predominantly rye grass (Lolium perenne L) pasture. Included in the design were pasture plots without trees (Control). The experiment is grazed by sheep yearly from April to …

A Silvopastoral System In The North Atlantic Zone Of Costa Rica: Combining Indigenous Timber Species With Dairy Pasture Swards, A Moulaert- Quiros, J P. Mueller, M Villarreal, R Piedra, L Villalobos

IGC Proceedings (1977-2023)

The objective of this study was to design, establish and monitor a silvo pastoral experiment on a dairy farm in the northern Atlantic region of Costa Rica. Indigenous timber species, Vochysia guatemalensis and Hyeronima alchorneoides were used together with or without the tropical pasture legume, Arachis pintoi in a split plot design with a 4 x 2 x 2 factorial arrangement. First year establishment was good for the tree component (2.3 to 10 % mortality) but poor for A. pintoi (4 to 5 % of sward). Poor legume establishment was attributed to lax grazing management and excess competition from existing …

Productivity Of Three Tree Legumes Grazed By Cattle, R C. Gutterridge

IGC Proceedings (1977-2023)

Three tree legumes Albizia chinensis, Leucaena leucocephala K 636 and Tipuana tipu were grown in conjunction with the grass Brachiaria decumbens and grazed by weaner cattle at a stocking rate of 2.5 animals per hectare for a total of 447 days. Albizia was best adapted to this acidic, poorly drained site in south east Queensland giving the highest yields of edible dry matter, high survival rate and moderate liveweight gains of 0.45 kg/head/day. The productivity of L. leucocephala K 636 was always poor but it gave the highest liveweight gains of all treatments in the first 280 days of grazing, …

Morphological And Physiological Response Of Planeleaf Willow (Salix Planifolia Pursh.) To Simulated Browsing, L Xu, J L. Dodd, M A. Smith, Q D. Skinner, W A. Laycock

IGC Proceedings (1977-2023)

Morphological and physiological responses of planeleaf willow (Salix planefolia Pursh.) to simulated browsing were studied under controlled conditions. The treatments consisted of every combination of three clipping intensities (30%, 60% and 90% of current twigs length removal) and three clipping timings (late winter, early spring and mid-summer). Increased clipping intensity stimulated bud activation; increased total leaf area and leaf size and increased the length of current year’s twigs. Mid-summer browsing increased the total number of leaves, the number of current twigs and decreased the length of current twigs. Higher browsing intensity resulted in higher photosynthetic rate of recently matured …

Psyllid Resistance In The Leucaena Genus, B F. Mullen, H M. Shelton, F Gabunada, W W. Stur

IGC Proceedings (1977-2023)

Leucaena species varied from highly susceptible to highly resistant in their response to the psyllid insect (Heteropsylla cubana) at 2 sites, a high psyllid environment at Brisbane, Australia and a moderate psyllid environment at Los Baños, Philippines. L. leucocephala was the most susceptible species. There was considerable intraspecific variation in psyllid resistance within L. collinsii, L. diversifolia and L. pallida. Plant reponse to psyllid challenge between environments was highly correlated but not linear. The higher psyllid challenge environment at Brisbane permitted greater discrimination between species and fewer Leucaena species were ranked as psyllid resistant.

Fodder Production Of Multipurpose Trees In A Maize Farming System Of Subhumid Southern Africa, B H. Dzowela, L Hove, P L. Mafongoya

IGC Proceedings (1977-2023)

Ways to integrate fodder production into maize production systems under Southern Africa’s subhumid conditions have been studied. One way involves the planting of tree and grass fodder hedges along soil conservation contour-bunds in maize fields. Management factors that influence the productivity of maize and fodder components in the system are fodder spp., side-pruning and deferment of wet season cutting. The other option involves interplanting tree fodders with maize through the use of a coppicing tree such as Acacia angustissima. Practical applications of these methods in mixed crop-livestock production systems are discussed.