Recent advances in techniques to optimize potato irrigation, role of deficit irrigation, and canopy measurement to predict effects of water stress are discussed in this paper.Real-time, continuous monitoring of soil water content in the soil profile was evaluated to optimize irrigation to supply water during the potato growing season while minimizing leaching losses below the rootzone.Soil water content was monitored at 10, 30, 60, 90, and 120cm depth in a Center Pivot irrigated potato (cv.Ranger Russet) field on a Quincy fine sand in southeastern Washington state.Depth integrated soil water content was calculated within the rooting depth (0~60cm) and below the rooting depth (60 ~ 120cm).Irrigation was scheduled to replenish full evapotranspiration (ET).The soil water content at the 10 and 30cm depth, as well as depth integrated soil water content in the 0 ~60cm depth soil responded to each irrigation event.The "Full Point" and "Refill Point" for the soil within potato root zone (0 ~ 60cm depth) were estimated to represent the maximum water holding capacity, and the soil water content at which irrigation is to be scheduled to avoid water stress, respectively.Depth integrated soil water content in 0 ~ 60cm depth soil profile remained mostly close to or above the Full Point during most of the growing season.However, the depth integrated soil water content below the rootzone (60 ~120cm) revealed no indication of water leached from the soil above.The sensor technology and automation of soil water measurements described in this paper has real merit in improving irrigation to minimize leaching losses, while maintaining adequate water in the rootzone to avoid any negative effects of water stress.However, the irrigation setpoints estimated in this study need to be reevaluated and readjusted.Potato tuber yield and quality are highly sensitive to irrigation and nitrogen (N) management.This study was conducted in the lower Columbia Basin production area in the Pacific Northwest, US to evaluate effects of deficit irrigation (DI) on Ranger Russet and Umatilla Russet cultivars.In 2004, with Ranger Russetonly, DI with 20% lower total irrigation for the growing season as compared to irrigation to replenish full evapotranspiration (ET) resulted in 28% tuber yield reduction.A subsequent study in 2006 ~ 2007 with DI (14% to 17% deficit) resulted in tuber yield reduction of 7% to 10% in both cultivars as compared to that with full ET irrigation.Yield reduction in DI was generally attributed to reduction in > 227g size tubers in both cultivars.Furthermore, hyperspectral imaging was used as a non-destructive method of detecting changes in spectral reflectance from potato plants grown under different soil water content.An imaging platform with a hyperspectral camera of waveband range from 400nm to 1000nm was used to acquire spectral images of leaves and canopies of these plants.Various indices were evaluated using spectral reflectance data at different stress levels.Spectral indices having strong correlation with plant stress were chosen and used for developing a regression model to predict soil moisture content level.Red Edge NDVI, Modified NDVI, Modified Red Edge SRI, VOG REI 1, VOG REI 2 and VOG REI 3 were found to be strongly correlated with soil moisture level.Thus the above indices can be used to predict the plant response to various levels of water stress.Highest correlation coefficient was found to be-0.9 for VOG REI 1 followed by 0.886 for VOG REI 2.The results showed promise for development of spectral sensor for non-contact soil-moisture content monitoring system and an automated irrigation system to maintain an optimal soil moisture content level during potato growing season.