Pots were treated monthly with 5 : 1 : 5 N : P : K fertiliser andHygrotech1Seedling Mix to provide micronutrients(excluding Si). Plants were drip irrigated at a rate ofbetween 0.33 and 1.0 L/pot/day, depending on stage ofplant growth. Plastic basins were placed beneath the potsto collect leachate, which reduced nutrient loss (especiallySi) and ensured a constant water supply.Plants were sprayed monthly with insecticide (chlor-pyriphos at 2 mL/L water) to prevent possible feral infestationsby E. saccharina and other pests (aphids, leafhoppers, scale,ants and mealy bugs). Spraying was halted well before inocu-lation with E. saccharina (see below) to ensure that no residueremained on plants at this time.Soil and leachate samples were taken on several dates(Table 3) from three adjacent end pots of each of the sixrows to monitor growth-medium Si levels. Two TVD leafsamples and two separate stalk samples were taken from allpots (Table 3) and composited by Si treatment and varietyto establish plant-Si levels, using the procedures of Fox et al.(1967). For the first stalk sample, the secondary tillers andone primary tiller were taken per pot. The second samplewas taken at harvest and consisted of all stalk materialundamaged by borer. Because more material was availablefor the second stalk sample, material from separate pots didnot need to be composited as above, allowing for a largersample size (Table 3). Leaf analyses to determine if all plantnutrient levels were within acceptable limits employedroutine nutrient determination procedures of the FertiliserAdvisory Service, S.A. Sugar Association ExperimentStation (SASEX).After 8.5 months of growth the water supply was reducedin a staged fashion to induce moisture stress, such that atthe end of one month plants had approximately (and no lessthan) five green leaves each. Stress increases the susceptibilityof sugarcane to E. saccharina as well as the quantity ofnitrogen in the stalk, both of which improve borer survivaland mass (Atkinson & Nuss, 1989).