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Nitrogen (N) fertilization is a key factor in determining potato (Solanum tuberosum L.) yield, especially on sandy soils. A two-year field study was conducted in the Columbia Basin region of Oregon to determine the effect of N fertilizer rates (0, 157, 280, 404, and 527 kg ha− 1) on tuber yield and quality. Elevated tuber yield and high tuber quality were associated with Castle Russet and Echo Russet, suggesting that the newly released cultivars suit the Columbia Basin region. Regardless of cultivars and years, the total and US No. 1 tuber yields increased when the N rate was 280 kg N ha− 1. Increasing N supply further did not affect or even tended to decrease potato yield especially when N was at 527 kg N ha− 1. The yield of tubers > 283 g and culls increased with increasing N rates up to 280 kg ha− 1 but then decreased at 404 kg N ha− 1 and at 527 kg N ha− 1. Moreover, the specific gravity and the fry color of potatoes were not affected by the N rate. As the petiole nutrient concentrations were associated with tuber yields, their values at the N levels of 280 to 404 kg ha− 1 might be used by producers in deciding fertilization, especially N. More data should be collected to create the critical petiole nutrient concentrations for developing management practices for these new cultivars. [ABSTRACT FROM AUTHOR]

Lodging in cereal crops can result in yield loss and harvesting difficulties for growers. Application of plant growth regulator (PGR) has been an indispensable management practice to reduce lodging problems that are often exacerbated during high wind growing conditions and/or high nitrogen (N)/water environments, but the data is limited in the Columbia Basin of Oregon. The objective of this research was to evaluate the effect of two PGR products (chlormequat chloride-CC, trinexapac-ethyl-TE) at different rates and application timings on two soft white winter wheat varieties (ORCH-102 and SY Ovation). Crop growth (stem height and thickness), yield-related (spike density as ears m−2, seeds per spike, grain weight) and quality parameters (test weight, protein) were measured for two cropping seasons from October 2017 to July 2019 following the application of the two PGR products at tillering (GS21-26), stem elongation (GS30-32), and/or flag leaf (GS37-39) stages under a high-N fertilizer scenario. In both growing seasons, no lodging problems were recorded for any treatments. The plant height was reduced after PGR application, but the impact on stem thickness was limited. PGR application slightly affected wheat yield, yield components, testing weight, and protein level in both growing seasons. Our results suggested that the effect of PGR application is relatively limited if no lodging problem occurred. [ABSTRACT FROM AUTHOR]