Non-Native Eragrostis curvula Impacts Diversity of Pastures in South-Eastern Australia Even When Native Themeda triandra Remains Co-Dominant

Lowland grassy woodlands in Australia’s south-east face reductions in native plant diversity because of invasion by non-native plants. We compared the relative abundance and diversity of plant species among sites dominated by the native Kangaroo grass (KG) Themeda triandra with sites co-dominated by the non-native African lovegrass (ALG) Eragrostis curvula and KG. We found significant differences in plant species composition depending on the dominant species. Furthermore, our results revealed differences in several diversity parameters such as a lower species richness and forb diversity on sites co-dominated by ALG and KG. This was the case despite the functional similarity of both ALG and KG—both C4 perennial tussock grasses of a similar height. Therefore, our results highlight the critical function of the native KG in maintaining and enhancing the target plant species composition and diversity within these grassy woodlands. Herbivore grazing potentially impacts on the abundance of the dominant grass and forb species in various ways, but its impact likely differs depending on their evolutionary origin. Therefore, disentangling the role of individual herbivore groups (native-, non-native mammals, and invertebrates) on the plant community composition of the lowland grassy woodlands is essential to find appropriate grazing regimes for ALG management in these ecosystems.

Dynamics of the ground layer communities of tropical eucalypt woodlands of northern Queensland

This paper presents insights from long-term monitoring into the dynamics of savanna plant species composition, specifically on the ground layer. Key questions are (1) how much variation is there from year to year in plant species abundance and composition? And (2) is there evidence of directional change in community composition? Five sites were located near Mareeba, north-eastern Australia, and sampled 18 times with fixed 500-m2 plots at the annual peak of plant species richness over 23 years. The sites were located in eucalypt communities across an altitudinal range of 460 m. Sampling involved systematic searching of all plant species visible above ground. The results show variation from year to year among satellite herbaceous species, with more than 50% of grasses and forbs observed at a given site only being detected at half or fewer of the 18 samplings. Herbaceous composition did not show clear signs of directional change relative to inter-annual variability. Over the 23 years, there were three very dry periods and 4 very wet years. Rainfall variation affected total cover more than plant species composition or richness. Several fires and episodes of grazing affected ground cover but did not have a lasting impact on cover or diversity. The cover and composition of the ground layer is consistently dominated by the core perennial grasses Themeda triandra Forssk. and Heteropogon triticeus (R.Br.) Stapf, with many species collectively contributing minimally to the overall cover but significantly to richness. Many herb species are persistent long-lived perennials which do not appear above ground every year. The number of naturalised plants in the ground layer was consistently low. Overall, the ground layer communities appear to be very stable in these woodlands that have been burnt 3–5 times in 23 years. High inter-annual variability of subdominant species is consistent with other studies, and emphasises the need for replication in time in ecological sampling.

Ranking Species for Veld Restoration in Semi-Arid Regions Using Agronomic, Morphological and Chemical Parameters of Selected Grass Species at Different Developmental Stages under Controlled Environment

The establishment of complementary native grass species could be an ideal method of dealing with existing problems of veld degradation and inadequate forage quantity and quality of pastures. A greenhouse experiment was conducted to evaluate the effect of native grasses viz., Anthephora pubescens, Cenchrus ciliaris, Chloris gayana, Dactylis glomerata, Digitaria eriantha, Eragrostis curvula, Festuca arundinacea, Panicum maximum and Themeda triandra. Attributes at different growth stages on agronomy, morphology and chemical composition were checked. Panicum maximum had the broader (p < 0.05) leaves across all growth stages when compared to all other grass species. Festuca arundinacea had highest (p < 0.05) number of tillers than C. ciliaris, C. gayana, D. glomerata, D. eriantha, E. curvula, P. maximum and T. triandra at 2–4-months age. Within each species, all grasses had the highest (p < 0.05) number of leaves at maturity. Chloris gayana, D. glomerata and P. maximum had the highest (p < 0.05) biomass yield when compared to F. arundinacea at the elongation stage. Eragrostis curvula had the highest (p < 0.05) crude protein (CP) values when compared to all other grasses, except for D. glomerata, F. arundinacea and P. maximum at the elongation stage. Panicum maximum and T. triandra had the least (p < 0.05) acid detergent lignin (ADL) values when compared to all other grasses at both vegetative and the elongation stages. In the ranking, C. ciliaris, C. gayana, D. eriantha, E. curvula, P. maximum and A. pubescens outperformed the rest of the grasses on most parameters. With the low crude protein (CP) content of these grasses, protein supplementation is highly crucial for high performing ruminants, especially those animals that graze grasses as their sole diets.

Is a long hygroscopic awn an advantage for Themeda triandra in drier areas?

Themeda triandra has bigeniculate hygroscopic lemma seed awns that twist when wet and drying, thereby transporting the caryopsis across the soil surface into suitable germination microsites. The prediction that awns would be longer in drier grassland and have greater motility to enable them to move quickly and further to find scarce germination sites was tested in KwaZulu-Natal. Awns (n = 100) were collected from 16 sites across a mean annual precipitation gradient (575-1223 mm), ranging from 271-2097 m a.s.l. The daily movement of hydrated long and short awns (n = 10) across blotting paper was tracked for five days, and the rotational speed of anchored awns was measured. Awn length varied considerably (mean: 41.4-63.2 mm; sd: 3.44-8.99) but tended to increase (r = 0.426, p = 0.099) not decline, with increasing MAP. Awn length was unrelated to elevation, temperature and aridity indices. Long awns rotated at the same rate (2 min 48 sec) but moved twice as fast (46.3 vs. 22.1 mm day-1) and much further (maximum: 82.1 vs. 38.6 mm day-1) than short awns. Whether moisture limits awn development, the benefit of longer awns to negotiate densely tufted mesic grassland, and the multifunctionality of awns require investigation.

Ethno-veterinary practices of Poaceae taxa in Punjab, Pakistan

Background: Plant species of Poaceae family are not only used as fodder and forage but also contribute substantially in the treatment of various health disorders, particularly in livestock. Consequently, present study was aimed to document the therapeutic uses Poaceae taxa by the inhabitants of the Punjab Province to treat various veterinary health disorders. Methods: Semi structured interviews, group discussion and field walks were conducted to collected data. Furthermore, quantitative indices includingcultural significance index (CSI), relative frequency of citations (RFC), fidelity level (FL), and relative popularity level (RPL) andJaccard Index (JI) were adopted for data analysis. Results: Traditional uses of 149 plants belonging to 60 genera, 16 tribes of 5 sub families of Poaceae were recorded. Whole plant and leaves were the most consistent grazing parts with 40.94 and 29.53% contribution and decoction (35 reports) was the most preferred mode of administration. Majority of the plant species were employed to treat infectious diseases (25.93 %). and digestive disorders (14.10 %). Triticum aestivum depicted highest CSI, RFC and RPL levels at 8.00, 0.96, 1.00, respectively, followed by Oryza sativa and Poa annua . Likewise, T. aestivum and Saccharum spontaneum had 100 % FL and ROP. Jaccard index ranged from 12.25 to 0.37. Twelve plant species namely Chrysopogon zizanioides (anti-inflammatory), Pennisetum lansatum (improve bull fertility), Cymbopogon citratus (glandular secretion), Sorghum saccharatum and Themeda triandra (malaria), Aristida funiculate (anticancer) , Koeleria argentia (skin allergies), Tetrapogon villosus (antibacterial), Cynodon radiates (eyes infection), Sporobolus nervosa (Jaundice), Enneapogon persicus (antifungal), and Panicum repens (dysfunctional cattle organs) were reported for the first time with novelethnoveterinary uses. Conclusion: Inhabitants of the study area had strong association with surrounding plant biodiversity and possess significant knowledge on therapeutic uses of grasses and other members of Poaceae to treat various health disorders in animals. Plant species with maximum cultural and medicinal values could be a potential source of novel drugs to cure health disorders in animals and human as well.

The diversity of thrips (Insecta: Thysanoptera) on buffel grass (Cenchrus ciliaris) is markedly lower than on native grasses in an urban landscape

Buffel grass (Cenchrus ciliaris) is a perennial tussock grass native to parts of Africa and southern Asia but is now distributed throughout much of mainland Australia. Corresponding with its presence in Australia has been an alteration of fire regimes and soil nutrients, and a reduction in floral diversity. We investigated whether buffel grass supported a less diverse community of thrips (order Thysanoptera) compared to the native grasses Cymbopogon ambiguus and Themeda triandra growing in Alice Springs, central Australia. The survey data showed that abundance was highest on buffel grass; however, the thrips community was almost entirely dominated by one species. The thrips communities on the native grasses were similar and markedly more diverse than that on buffel grass, both in terms of species richness and functional feeding groups. Flower feeders constituted the greatest proportion of thrips on all three grasses, but the native grasses also supported leaf feeders and predators. The results indicate that thrips are sensitive to vegetation change, and we suggest that active removal of buffel grass and replacement with local native grasses would help reverse the loss of biodiversity and normal ecological function in urban areas like Alice Springs. We also suggest that the order Thysanoptera is under-utilised in biodiversity research.