thornei costs 4.3% of the total wheat production/year in the eastern Australian subtropical grain region, with this loss valued at AU$38 million ( Murray and Brennan 2009). 2014) from high population densities of P. 1999) and some chickpea genotypes up to 25% yield ( Reen et al. Some wheat genotypes can lose up to 65% yield ( Thompson et al. thornei is polyphagic, being hosted by many cereal and pulse crop species, including wheat and chickpea which, in other respects, are valuable rotational crops for each other. Deep cracking clay soils (vertisols) are favored for cropping in this region because of their high water-holding capacities to store fallow rainfall to supplement rainfall during the next crop phase ( Webb et al. Major cool-season crops, termed winter crops, are wheat, barley ( Hordeum vulgare), and chickpea ( Cicer arietinum), while major warm-season crops, termed summer crops, are sorghum ( Sorghum bicolor) and mung bean ( Vigna radiata), with a number of other cereal, pulse, and oilseed crop species grown to lesser extents. This region, which lies between latitude 20°S in Queensland and latitude 32°S in New South Wales, is characterized by rain-fed agriculture dependent on dryland farming practices, with a range of broad-acre crop species grown throughout the year.
The root-lesion nematode Pratylenchus thornei is a major pathogen of wheat ( Triticum aestivum) in many regions of the world ( Smiley and Nicol 2009), particularly subtropical and warm temperate zones such as the subtropical or northern grain region of eastern Australia ( Thompson et al. However, resistant germplasm characterized in this study could be used in plant breeding to considerably improve the overall resistance of Australian wheat crops. Most (62%) Australian wheat genotypes were in the most susceptible three categories (susceptible, susceptible to very susceptible, and very susceptible). Nine genotypes were nominated as references for future resistance experiments. Nine categories of resistance ratings for wheat genotypes from resistant to very susceptible were based on subdivision of the range of PA(1+2)-eBLUPs for use in growers’ sowing guides. thornei-infested fields in the Australian subtropical grain region.
thornei as empirical best linear unbiased predictors (PA-eBLUPs) from the combined glasshouse experiments were highly predictive ( P < 0.001) of final nematode population densities in the soil profile, crop canopy greenness (normalized difference vegetation index), and grain yield of wheat genotypes in P. Principal axes 1 and 2 (PA1 and PA2) accounted for 79 and 11% of the genetic variance, respectively, over all experiments. thornei of the genotypes was effectively represented by a two-factor model with rotation of the axes to a principal components solution. thornei for 1,096 unique wheat genotypes in 22 glasshouse experiments. Here, we use a factor analytic method for multiexperiment analysis of final population densities of P. thornei can be determined from final nematode population densities in glasshouse experiments but combining results across multiple experiments presents challenges.
The root-lesion nematode Pratylenchus thornei is a major pathogen of wheat ( Triticum aestivum) in many regions globally.