Baioni, S. S.

Brevedan, R. E.

Fioretti, M. N.

Laborde, H.

Toribio, M. B.

English

University of Kentucky

University of Kentucky UKnowledge International Grassland Congress Proceedings 21st International Grassland Congress / 8th International Rangeland Congress Digitaria eriantha under Water Deficiency H. Laborde Universidad Nacional del Sur, Argentina M. B. Toribio Universidad Nacional del Sur, Argentina M. N. Fioretti Universidad Nacional del Sur, Argentina R. E. Brevedan Universidad Nacional del Sur, Argentina S. S. Baioni Universidad Nacional del Sur, Argentina Follow this and additional works at: https://uknowledge.uky.edu/igc  Part of the Plant Sciences Commons, and the Soil Science Commons This document is available at https://uknowledge.uky.edu/igc/21/7-1/14 The 21st International Grassland Congress / 8th International Rangeland Congress took place in Hohhot, China from June 29 through July 5, 2008. Proceedings edited by Organizing Committee of 2008 IGC/IRC Conference Published by Guangdong People's Publishing House This Event is brought to you for free and open access by the Plant and Soil Sciences at UKnowledge. It has been accepted for inclusion in International Grassland Congress Proceedings by an authorized administrator of UKnowledge. For more information, please contact UKnowledge@lsv.uky.edu. 　 Multifunctional Grasslands in a Changing World 　 Volume Ⅰ 　 瞯 ]831　 瞯Grasslands/Rangelands Resources and Ecology ———Water Resources in Grasslands/RangelandsDigitaria eriantha under water deficiencyLaborde , H . , M .B .Toribio , M .N .Fioretti , R .E .Brevedan and S .S .BaioniDepartment o f A gronomy , Universidad Nacional del Sur and CERZOS , CON ICET , A ltos del Palihue , 8000 Bahí aBlanca , A rgentina .E‐mail : ebreveda＠ criba .edu .arKey words :water use efficiency , forage quality , in v itro dry matter digestibility , neutral detergent fiber , nitrogen .Research on dryland pastures in the semiarid regions of Argentina has concentrated mainly on aspects such as potentialproduction related to quantity and quality as well as fertilization requirements .But since soil water is the most limitingenvironmental factor that affects plant production in these areas , the water use efficiency and the quality of the pasture underwater limited conditions should be considered .Even if water stress is the most important physical limitation to plant yield thereare contradictory results about its effect on nutritive value .Digitaria eriantha is a highly palatable perennial C４ grass which can be grown in most of the semiarid areas of Argentina .Ithas the potential to become one of the most widely pasture grass in those areas .The climate during its growing season ischaracterized by considerable fluctuations of rainfall .Water stress effects on D .eriantha quality has not been studied .The purpose of this study was to determine the effect of moisture regimes on yield , water use efficiency and quality of D .eriantha .This study was conducted at the greenhouse and the experimental field of the Universidad Nacional del Sur at Bahía Blanca (３８°４４′S ６２°１５′W) .The soil was a typical ustipsament with a petrocalcic layer and a loamy‐sand texture .D .eriantha cv .Irene wasused .There were three treatments at the field : １ ) no irrigation , ２) irrigated every ７ days , and ３) irrigated every １４ days .A randomized complete block design was used .Plots were ５ .０ × ２ .８ m and there were ６ replicaes for each treatment .There were also ３ treatments in the greenhouse : a) １００％ , ２ ) ７５％ and ３) ５０％ field capacity .Forage was dried at ６５°C , weighed and ground for chemical analysis .Nitrogen was determined by the semimicro‐Kjeldahlmethod (Bremmer , １９９６ ) and then multiplied by ６ .２５ to obtain crude protein ( CP) , phosphorus concentration was obtained byMurphy and Riley (１９６２ ) .In v itro dry matter digestibility was determined by Terry and Tilley (１９６４) , neutral and acid detergent fiber and lignin by VanSoest et al (１９９１) .There was a good correlation between yield and the availability of soil water .The production of D .eriantha with ７５ and ５０％ offield capacity was reduced ８１ and ５６％ compared to treatment of １００％ of field capacity .The water use efficiency was ６ .３８ kgha‐１ mm‐１ .Water stress had a smaller effect on forage quality than on grow th .Drought reduced the seasonal decline in digstibility( IVDMD) by reducing the rate of increase in acid detergent fiber and lignin compared to non‐stressed plantas .This can be dueto a delay in plant grow th .Water deficit decreased the rate of seasonal decline in nitrogen content , may be by a decrease in leaf senescense , but there wasa reduction of phospohours concentration .The response of plants to water stress depends on the time of the stress .Most of the effects on forage quality were positive ,may be due to a delay in maturity caused by water stress .At later times the stress accelerate the maturation .ReferencesBremmer , J .M .１９９６ .Nitrogen total .In : Methods of soil analysis .Part ３ .Chemical methods . Soil Science Society o f America ,Madison ,Wi , USA .Murphy , J .and J .P .Riley .１９６２ . A modified single solution method for the determination of phosphate in natural waters .Analytical Chimica Acta ２７ : ３１‐３６ .Tilley , J .M .A .and R .A .Terry .１９６３ .A two‐stage technique for the in v itro digestion of forage crops . J .British G rasslandSociety １８ : １０４‐１１１ .Van Soest , P . , J . Robertson and B . Lewis . １９９１ . Methods for dietary fiber , neutral detergent fiber and non starchpolysaccharides in relation to animal nutrition . J .Dairy Science ７４ : ３５８３‐３５９７ .

\u3cem\u3eDigitaria eriantha\u3c/em\u3e under Water Deficiency

https://uknowledge.uky.edu/cgi/viewcontent.cgi?article=2883&amp;context=igc

\u3cem\u3eDigitaria eriantha\u3c/em\u3e under Water Deficiency

Abstract

Similar works

Full text

Available Versions

University of Kentucky