Soil Temperature, Water, and Phosphorus Effects upon Barley Growth1

Abstract

AbstractBarley (Hordeum vulgare L.) growth in the northern Great Plains is often limited by soil water, soil temperature, or soil fertility. Therefore, we investigated the sponse of ‘Sacramento’ spring barley to three levels each of soil temperature (T), water (W), and P fertility in a growth chamber. The yield of oven‐dry tops, crowns, and roots showed the beneficial effects of increased W and P on barley growth for all soil temperatures studied. Response of top and crown weight to added P declined as T increased or W decreased. Crown weight was highly correlated with numbers of tiller plus root buds initiated at the crown. The addition of P increased the numbers of tiller and root buds. Low available water and high soil temperature decreased the number of root buds per tiller bud. When low W limited barley growth, root weights were maintained in preference to top weight, and top weight in preference to crown weight. Where the fertilizer needs of barley have been met, methods devised to conserve water and control soil temperature at or slightly below optimum near developing root systems should favor yield responses.