Bhuiyan S.A.,Sugar Research Australia SRA |
Croft B.J.,Sugar Research Australia SRA |
Stirling G.R.,Biological Crop Protection |
Wong E.,Sugar Research Australia SRA |
And 2 more authors.
Australasian Plant Pathology | Year: 2016
Root lesion nematode (Pratylenchus zeae) and root knot nematode (Meloidogyne javanica) are the two most important nematode pathogens of sugarcane in Australia. They cause significant yield loss but there are no known varieties with resistance. A research project commenced in 2011 to assess the level of nematode resistance in the progenies from clones derived from crosses between sugarcane (Saccharum spp.) and Erianthus spp. or Saccharum spontaneum Since standard methods of assessing nematode resistance in sugarcane clones were not available, the study aimed to develop rapid, effective and reliable methods for the screening of large numbers of clones for resistance to root lesion and root knot nematodes. A second objective was to determine the resistance of basic Saccharum spp., their wild relatives and some selected crosses to these two nematodes. Shoot and root biomass, reproduction factors (RF) and number of nematodes (or eggs) per g of roots were used to assess resistance levels. A visual rating of root galling was also used for root knot nematodes. The RF value, nematodes or eggs per g of roots, and visual rating (for root-knot nematode) were highly correlated. Resistant and susceptible clones were distinguished using any of these methods. It is concluded that the RF values can be used to detect nematode resistance in large numbers of clones. In the case of root-knot nematodes, visual gall ratings produced results that were similar to egg counts, and could be used as an alternative in future. For advanced clones, rating based on nematodes or eggs per g of root is likely to provide more accurate results. Basic S. spontaneum, E. arundinaceus clones and some progeny clones from crosses between these wild canes and commercial sugarcane clones, or from further backcrosses between these and sugarcane clones, were found to be resistant or moderately resistant to root-knot and root lesion-nematode. These clones are being further tested in the glasshouse and in the field, and should be useful sources of resistance for root-lesion and root-knot nematodes for sugarcane breeding programs. © 2016, Australasian Plant Pathology Society Inc.
Croft B.,SRA |
Bhuiyan S.,SRA |
Magarey R.,SRA |
Piperidis G.,SRA |
And 7 more authors.
37th Annual Conference of the Australian Society of Sugar Cane Technologists, ASSCT 2015 | Year: 2015
THE HYBRIDISATION OF noble sugarcane, Saccharum officinarum, with its wild relative S. spontaneum in the early 1900s was responsible for greatly improved resistance to a number of diseases, increased vigour and improved ratooning. New crosses made in Australia with S. spontaneum clone Mandalay during the 1960s resulted in the important parent clone, QN66-2008, which is the parent of 25 and grandparent of 18 'Q' varieties. Introgression breeding requires many years of crossing, screening of progeny and backcrossing to retain the beneficial characteristics while reducing the negative characters associated with the wild relatives, such as low sugar and high fibre. A collaborative introgression breeding program between CSIRO, BSES/SRA and Chinese research organisations commenced in 2000. Chinese breeders made crosses with Erianthus spp. and S. spontaneum from Asia. Seed and clones from this program were imported into Australia through quarantine and have been tested for yield and disease resistance. A selection of over 600 introgression clones has been screened for resistance to pachymetra root rot, root knot nematode, root lesion nematode and smut. Some clones from the advanced backcrosses that are resistant to these diseases have been identified and are currently being further tested for potential as commercial varieties or as parents to provide new sources of resistance to the diseases and to broaden the genetic base of commercial varieties. This paper reports on the variation in resistance to diseases of the introgression crosses from sugarcane wild relatives including the disease resistance of true crosses with the genus Erianthus.
Stirling G.R.,Biological Crop Protection |
Halpin N.V.,Agri Science Queensland |
Bell M.J.,Agri Science Queensland
Nematropica | Year: 2011
Most Australian sugarcane crops are harvested green, with the crop residues left behind after harvest remaining on the soil surface as mulch, a process known as green cane trash blanketing. Sampling in trash-blanketed sugarcane fields showed that roots were present to a depth of 150 cm, but that more than 90% of the root biomass was in the upper 30 cm of the soil profile. Many of these roots were concentrated in a layer just below the trash blanket and they were unusually healthy, presumably because population densities of Pratylenchus zeae/g root were 5-16 times lower than in roots a few cm further down the profile. Results of a microcosm experiment indicated that mulching soil with sugarcane residue increased soil C, microbial activity and numbers of free-living nematodes, and enhanced suppressiveness to Meloidogyne javanica and P. zeae to a greater extent than incorporating the residue into soil. It is hypothesized that roots immediately beneath the trash blanket remain healthy because C inputs from root exudates and organic matter on the soil surface sustain a soil food web capable of suppressing root pathogens, including plant-parasitic nematodes.
Smith M.K.,Maroochy Research Station |
Smith J.P.,Maroochy Research Station |
Stirling G.R.,Biological Crop Protection
Soil and Tillage Research | Year: 2011
Ginger (Zingiber officinale) production is facing increasing disease and pest pressure and declining yield with continuing intensive cultivation practices. A four year experiment was established in south-eastern Queensland on a red ferrosol that had a long (>60 years) history of ginger farming. Minimal tillage and organic amendments were compared with conventional practice that involved frequent tillage and soil fumigation using 1,3-dichloropropene (Telone®). Ginger crops were grown in the second and fourth year of the experiment, following an annual rotation with different cover crops including oats (Avena sativa), Brassica spp., soybean (Glycine max) and forage sorghum (Sorghum bicolour X S. sudanese). A pasture ley of Pangola grass (Digitaria eriantha subsp. pentzii) provided a treatment continuum from major to minor disruption in the soil's physical fertility and biological communities, and was therefore only planted to ginger in the fourth year of the experiment. Ginger seed-pieces (sections of the rhizome used for planting) were planted into both tilled and untilled beds using a double disc opener on a specially designed ginger planter. Rhizome yield in the final year was greatest (74.2t/ha) and losses to pathogens (Pythium myriotylum and Fusarium oxysporum f. sp. zingiberi) minimal (7.0%) in the pasture ley that had been cultivated prior to planting ginger. Furthermore, the minimum-tilled cover cropped treatment, which likewise had been cultivated prior to planting ginger, yielded well (62.0t/ha), with few losses (5.0%) from rhizome rots. Conversely the fumigated treatment had the highest losses (35.9%) due to Pythium Soft Rot and lowest yields (20.2t/ha). Minimum-tilled plantings of ginger, however, resulted in poor yields (30.9-43.1t/ha) but had acceptable levels of disease. © 2011 Elsevier B.V.
Hayward A.C.,University of Queensland |
Fegan N.,Food Science Australia |
Fegan M.,University of Queensland |
Fegan M.,Australian Department of Primary Industries and Fisheries |
Stirling G.R.,Biological Crop Protection
Journal of Applied Microbiology | Year: 2010
Summary The exploration of new source materials and the use of alternative isolation and identification methods have led to rapid expansion in the knowledge of diversity; in Lysobacter, 11 new species having been described since 2005, and in Stenotrophomonas with six new species since 2000. The new species of Lysobacter, isolated by dilution and direct plating on standard media, differ in several key phenotypic properties from those obtained by enrichment on complex polysaccharides in the original description of the genus. Revision of the definition of the genus will be required. Both culture-dependent and culture-independent methods to assess community structure, in a variety of host and nonhost environments, have established that some species of Lysobacter are a dominant component of the microflora, where previously their presence had not been suspected. Culture-independent studies have generally not added new information on the occurrence and distribution of Stenotrophomonas maltophilia and other members of the genus, which are readily isolated on standard media from source materials. Lysobacter enzymogenes and Sten. maltophilia produce similar antibiotics and share some enzyme activities which, subject to safety considerations, may make them attractive candidates for use in biological control of plant diseases and of nematodes. © 2009 The Society for Applied Microbiology.