Commensalism in an agroecosystem: hydraulic redistribution by deep‐rooted legumes improves survival of a droughted shallow‐rooted legume companion. Issue 1 (18th January 2013)

• Record Type: Journal Article
• Authors: Pang, Jiayin; Wang, Yanmei; Lambers, Hans; Lambers, Hans; Tibbett, Mark; Siddique, Kadambot H. M.; Ryan, Megan H.
• Is Part Of: Physiologia plantarum. Volume 149:Issue 1(2013:Sep.)
• Page Start: 79
• Page End: 90
• Publication Date: 2013-01-18
• Subjects: Plant physiology -- Periodicals; 571.2
• DOI: 10.1111/ppl.12020
• Languages: English
• ISSNs: 0031-9317

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>We investigated commensalism of water use among annual shallow‐rooted and perennial deep‐rooted pasture legumes by examining the effect of hydraulic lift by <italic>Cullen pallidum</italic> (N.T.Burb.) J.W.Grimes and <italic>Medicago sativa</italic> on growth, survival and nutrient uptake of <italic>Trifolium subterraneum</italic> L. A vertically split‐root design allowed separate control of soil water in top and bottom soil. Thirty‐five days after watering ceased in the top tube, but soil remained at field capacity in the bottom tube, an increase in shallow soil water content by hydraulic lift was 5.6 and 5.9 g kg<sup>−1</sup> soil overnight for <italic>C. pallidum</italic> and <italic>M. sativa</italic>, respectively. <italic>Trifolium subterraneum</italic> in this treatment maintained higher leaf water potentials (with <italic>M. sativa</italic>) or exhibited a slower decline (with <italic>C. pallidum</italic>) than without companion perennial plants; and shoot biomass of <italic>T. subterraneum</italic> was 56% (with <italic>C. pallidum</italic>) and 67% (with <italic>M. sativa</italic>) of that when both top and bottom tubes were at field capacity. Uptake of rubidium (a potassium analog) and phosphorus by <italic>T. subterraneum</italic> was not facilitated by hydraulic lift. Interestingly, phosphorus content was threefold greater, and shoot biomass 1.5–3.3‐fold greater when <italic>T. subterraneum</italic> was interplanted with <italic>C. pallidum</italic> compared with <italic>M. sativa</italic>, although dry weight of C. <italic>pallidum</italic> was much greater than that of <italic>M. sativa</italic>. This study showed that interplanting with deep‐rooted perennial legumes has benefited the survival of <italic>T. subterraneum</italic>.</p> </abstract>