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Despite the popularity of bermudagrass (Cynodon dactylon L.) around the world, there are few studies that report genotypic and seasonal variation for sprouting of stolons used in pasture establishment or revegetation of disturbed land. This study investigated the genotypic/seasonal variation and the physiological basis of sprouting from nodes of aboveground stolons among 12 bermudagrasses. Sprouting percentage, total nodes per m (Nds), stolon diameter (SD), total aboveground biomass (TaB), and concentration of water soluble carbohydrate [WSC], concentration of starch [starch], concentration of non-structural carbohydrate [NSC], and concentration of crude protein [CP] were determined in different seasons including winter 2013, winter 2014, spring 2014, summer 2015, and fall 2015. Sprouting percentage for stolons sampled in spring and summer was higher than that for winter and fall. Large genotypic variation for sprouting was observed ranging from 44.1 to 80.2% of all nodes when averaged across seasons. Sprouting percentage among genotypes was strongly associated with SD, TaB, and Nds; and weakly associated with concentrations of photoassimilates such as [WSC], [starch], and [CP] in the aboveground biomass. However, when these photoassimilates were calculated as an amount per node, sprouting percentage was highly correlated with water soluble carbohydrate (WSC) (r = 0.80), crude protein (CP) (r = 0.82), and WSC + CP (r = 0.88). These data suggested that the size and/or maturity of the axillary buds at nodes and the available assimilate supply was underlying the sprouting potential of the bermudagrasses, however, more research under field conditions is required to validate this claim.

A large collection of over 1000 naturalised Australian bermudagrasses (Cynodon dactylon) was assembled. Previous research indicated that a subset of the grasses collected from Australian Mediterranean environments were drought resistant and characterised by large rhizomes that could be a potential source of nutrients, water and carbohydrates when these grasses grow under saline conditions. The objective of this research was to test the salinity tolerance of 12 bermudagrass genotypes with different levels of drought resistance using a flood and drain, sand-solution hydroponic system. Eight salt treatments were imposed ranging from 1.3 to 21 dS m-1 (corresponding 0 to 175 mM NaCl) for up to 17 weeks. Salinity tolerance among genotypes was categorised on the basis of 50% reduction in cumulative clipping yields, verdure and root biomass, and green cover, relative to the control treatment. There was no correlation between salt tolerance and drought resistance (r = -0.079 to 0.572), although some drought-resistant grasses did have excellent salt tolerance, such as entries MED1 and MED3. At 21 dS m-1, most grasses not only maintained over 50% total biomass but also retained over 70% green cover, relative to the control treatment, and were considered as highly salt tolerant. These salt-tolerant grasses have great potential for stabilising and revegetating saline and/or sodic soils.

Soil erosion and stabilisation are huge problems facing Australian land users, including those working in agriculture, mining, road construction and urban sports and community landscapes. There is a large opportunity for the Australian turfgrass industry to play a role in providing solutions to Australiafs land stabilisation issues. If 10% of these denuded landscapes can be vegetated by turfgrasses, the turfgrass industry as a whole can benefit greatly, particularly in the current economic climate, where the hangover from the global financial crisis has persisted. Collectively, the areas to be stabilised are enormous and to date the methods used to revegetate these land masses are limited. Hydrosprigging (HS) is an inexpensive, automated method of delivering grass sprigs (stolons) with a hydraulic pump to large areas of bare soil. In this study, we present our latest research on developing state-of-the-art HS methods. Significant differences for stolon sprouting of up to about 30% were identified among 12 bermudagrass genotypes harvested from the field. We hypothesise that the sprouting potential and vigour of shoots may be a function of the levels of nonstructural carbohydrate (NSC) present in the stolons at the time of planting. We also suggest that photothermal quotient, the ratio of solar radiation to temperature during the growing period, may provide the theoretical basis for predicting when levels of NSC may be optimum through the growing season.