Root behavior and crop yield under irrigation /

Abstract

Plate 1. A. Yield of alfalfa from one square rod of dry land (left) and irrigated land (right) on July 26, of first season's growth. B. Yield of grain from one square rod of lightly irrigated wheat (two containers on left), fully irrigated but more sandy soil (center), and dry land (right), 1922.

Root Development of Winter Wheat as Influenced by Soil Moisture and Nitrogen Fertilization1

“…In 1875, Muller-Thurgau (6) concluded that relatively dry soil conditions induced plants to develop a more extensive root system than did moist soil conditions. This conclusion has been confirmed by other workers, especially by the numerous and exact measurements of Weaver and his co-workers ( 4,7). This concept raised questions concerning the development of an extensive root system when moisture is supplied abundantly, especially if nitrogen fertilizers :stimulate root growth near the soil surface rather than in deeper horizons.…”

“…The generalization of Muller-Thurgau may not hold under irrigated conditions. For example, Jean and Weaver ( 4) demonstrated that root growth, as measured by mass and depth of penetration, was increased many fold by irrigation. Weaver (7) states the Each moisture treatment was divided into eight nitrogen fertilizer treatments.…”

Summary and Interpretation of Underground Development in Natural Grassland Communities

“…Thus, a low water content, within certain limits, stimulates increased root branching (cf. Jean & Weaver 1924).…”

Soil‐Root Relationships of Certain Native Grasses in Various Soil Types

“…Some attention was givm to the response of root systems to the great drought (Weaver & Albertson 1943). These studies formed a hackground for similar studies of crop plants (W eaver, Jean, & Crist 1922;Jean & Weaver 1924;Weaver 1926;Weaver & Bruner 1927).…”