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{"metadata":{"id":"009b79445fc34b6b2a6bc533463ecb9b","source":"gardian_index","url":"https://cgspace.cgiar.org/rest/bitstreams/909c423c-84c7-4350-b022-244fa9f23601/retrieve"},"pageCount":32,"title":"~Nr!E~NO nm rorENTIAL OF Andropo¡on sayarws IWlth IN nm OXISOL AND ULTlSOL SAVANNAS OF TROPlOO-AMERICA","keywords":[],"chapters":[{"head":"","index":1,"paragraphs":[{"index":1,"size":58,"text":"• geographical d~stributlon almost idEln~lcal tO,that ol'var. sguamulatus north 01' the equato.... It does not occur south 01' the !'Iguator. Varieties squamulatus and bisguamulatus have .invaded man:'made savanna areas, throughout the nol\"'thern part ef the fOl\"'est zona in Nigel\"'ia (Adejuwoo. 1974). Val\"'.'btsguamulatus has beén !ntl\"'oduced tnto Colombia, South Amel\"'ica and gr:-ovvs vigerouslywitli a blmodal rainfall distribut!on 01' C5."}]},{"head":"\"","index":2,"paragraphs":[{"index":1,"size":19,"text":",'1 ove,.. 1800.mm annually.,and wi,th, a single 5 menth dry seaSon and 2100 m in 8 annual rainfan. 9"},{"index":2,"size":11,"text":"Varo gayanus occurs en seasonally I'looded land in West Africa ,,'"},{"index":3,"size":23,"text":"10 where it forms aL-nost pur ', stands (13ogdan. 1977;Bowden. 19~).: ~~ , 11 .aJ.so occur's south 01' the eqt.:;atorial rainforeste in Za\"ire."},{"index":4,"size":27,"text":"12 Va .... trldentatus Is shorter than val\"'. bisguamulatus and occurs In 13 the sem!desert parte 01' the Sahel zona 01' West Afrlca (Sogdan, 1977; . t."},{"index":5,"size":4,"text":"~ 14 Fester, 1962)."},{"index":6,"size":1,"text":"15"},{"index":7,"size":21,"text":"The \\iarietles sguamulatus. blsquamulatus and gaya,nus occur lG naturally where the average mlnimj.Jl'Tl temperature 01' the coldest winter . . ."},{"index":8,"size":23,"text":". 11 month doss I!ot fan below 4.4 C (Sowden, 1964b). The species tole-18 rates lIght frastE¡ (Chatte ... jee and Slngh. 1966)."},{"index":9,"size":1,"text":"19"},{"index":10,"size":9,"text":"Varletles squamulatus and bisguamulatus can wlthstand up to 9"},{"index":11,"size":35,"text":"'20 mentbs 01' drought, but ,their,most favorable environment appears to be below 1000 m yvlth a dry season 01' 3 to 5 months and a 'total rainfaU el' , , over 750.mm (Bogdan, 1977;SowdÉln, 190080)."},{"index":12,"size":2,"text":"Flowering behavior."},{"index":13,"size":23,"text":". Andropogon gayanus. Hke most members 01' tlJe Andr-opogoneae, (Evans. ,1964). lB a shor-t-day p l8ont. Its oritica\" daylangth ,fol\". flowerkl, , ."},{"index":14,"size":11,"text":"lI!i between 12 and 14 hl'\" (Tompsett. '197'6). Flowering!s IntenslFied b~."},{"index":15,"size":32,"text":"21 shortenlng daytength fr-OI'n J2 to a:hr at\" by exposing older' plants to the rainy season (Anon., 1942;Bogdan. 1977). The speclas ie weU adapted to burning. and' careful graztng management. periodic bUl\"ning."},{"index":16,"size":13,"text":"01\" cutting may be neeessary suppress the accumulatiO!\"\\ 01' old '''lb'r'OUs . \""},{"index":17,"size":1,"text":"."},{"index":18,"size":19,"text":"gayanus pastures Utter can\" ¡onstlli.lte more th&.n 50\"/0 01' the total ol\"gW'lic matter during the dry season (Egunjobt, 1974)."},{"index":19,"size":3,"text":", , '"},{"index":20,"size":34,"text":"In the eastel\"n savannas '01' Colombia the regl\"owth 01' nativa savanna is gl\"eatel\" than that ~ A. gayanus 1'01\" the.l'il\"st 4-5 days al'ter , bUl\"nlng; hoWever. within,.10 days ,~ regl\"ONth, of' A. gayanus greater."},{"index":21,"size":2,"text":", ,"},{"index":22,"size":16,"text":"Artel\" 6 weeks its I\"egrowth was 0'1191\" twlce that 01' natlve savanna (9'17 , , ."},{"index":23,"size":27,"text":"vs. 419 I<:g PM ha -1). Ligntl'lcation of' !;he I\"egrowth appeal\"S to ba mue\" stower In A. gayanus than in native savanna (M. Si!Ínchez. personal --, '"},{"index":24,"size":2,"text":", communtcation)."},{"index":25,"size":28,"text":"Varo bisquamulatus la known te aggresslvaly coloniza disturbe soU In both l'aUow flelds (P.N. de Leeuw. personal communicátion)and disturbed nativa savanna ( .. r.M. Spai\"'. personal communicatlon). In."},{"index":26,"size":80,"text":"northern Nigerla tt la aowri in'grass fal10w and lB known té, be useful in bunding sou rertillty (Bowden. 1963&.); Its benel'icial ert'ect en sub-:sequent cl\"'Oj:)s ,ls pr'obably due more te, tmprova soU rer.tntty,than toa .. : .; 11 less) 01' crown spllts appeal\"!, pra:nlslng. Evan when the land 'la pre-12 pared and spUts al\"'e planted late In the wet season, seed p~uctlon ma~ 13 be sufflcient to tnsure a good stand the'foUowingrainy ¡seaaon (.J. M. , 14 Spaln, personal communlca~lon)."}]},{"head":"'","index":3,"paragraphs":[{"index":1,"size":20,"text":"Seed.ma,y be aown I;lroaclc:ast.or In rows. Bowden (1963a) 12 Bowden (1963a) reviewed DM ylelds obtained in 5 Af'rlcan trials •. "}]},{"head":"t4.","index":4,"paragraphs":[{"index":1,"size":36,"text":"ful\"ther de creases followed. The IVOMO of elongating stems was as hlgh as that of leave!!!. Voluntary feed Intake wás relatad to NOMO \" \"3 (r=0.40) and CP (ril:: 0.82). Percentage crude protein was related to,'."},{"index":2,"size":27,"text":"pereentage éllgestlbte crude prOtein (r=0.88). Perc:entage crude protein'was concluded to be:a useful'crlterlon for,predictlng nutrltive wtues. The Impol\"tance or selectiVa ~umPttÓn of iOllV quaUty of . .!!. ,."},{"index":3,"size":3,"text":"... '.-:;: ."},{"index":4,"size":1,"text":")."},{"index":5,"size":6,"text":", , \" . \\ '."},{"index":6,"size":2,"text":"'. '"},{"index":7,"size":3,"text":".. . ,"},{"index":8,"size":2,"text":". \""}]}],"figures":[{"text":", . sqUamulatus ls a moderatet,Y vlgorous type not excee ling l.! m In height and Is the most widely dtstl\"'ibuted 01' the three val\"'ietlas. It, Is found on weU-drained soils throught tropical .Africa., NOl\"'th 01' the equator It extends In a wlde belt between the Sahara and the equatol\"'lal ralnforests fl\"Om Senegal on the west to too Sudan and northern Uganda on the eut. South 01' the equator It Is found In the savannas' to 'the east and I!!outh 01', the equatorlal ralnforests in Zaire and as far 'south as MOzambique ánd the Transvaal In South .Al'rlca. lt occurs up to' 2300, and occaslonalt,Y to 2600 m. . ~. ,Val\"'. blsquamutatus ,ls a lal\"ge vigorous type 'ol'tan exceeding 2 m• in he(ght. It (s I'cund on weH-dralned soU!!! to 2000 m aro has a I , . "},{"text":" . 1963a; Haggar. 1¡;¡70). In unburned ungrazed A. "},{"text":" long-lasting Improvement of soH phystcal properties(Wilklnson. 1975) _ , Andropogon gayanus ts adaptad te a range ofs,ol1 typelS tnc.l.Alng. ... r---~:---:--~-_ _ --.--\"\"\"---:----:-:--~---::--:-'-~\"'\" ,1 rleh al1uvlal solls(8arrault. ,1973). serpentina solls(Wild. 1974a and '2 1974b). Oxisots and, Ultisols (CIAT. 1977? and we1t dralned sandy clays ,3 011 medlum to hlgh fertility (8&den, H:)63a). opo9on gayanus may be establlshed ethr from crown spllts 6 or seed. Crown sptits areoften uSed In experimental work to quiekty .,7 estabUsh a unil'OI\"'m stand. Slnee the speciea ls altogarrious and plants '8 vary morphologleany spUts shoul~ be taken fl\"CJ!Tl a number 01' plants and '9 random~zed within a plot. Where seeifqualtty or other' factors prohlbtt 10 mechanized pianting 01' S~cI,lOW derúilly plantlng (1000 plants ha-1 01\" , "},{"text":"27 In hse trials~. gayanus was always among the three hlghest yieldlng specles. Ita yield was roughly ~parable to that 01' Panicum !: axlmulT • .. lt outyie\\ded 1:. maximum in two tt;'ials, ylelded less than.!:'.maximum in two tMals, ard proouced equlvalentyields In one trial.At 23\" North Latitute in India ~. gayanus and Brachlaria brizantha had aqual annuat Otvt yields (11 .6 tons ha-t ) and outylEollded the 10 other gl\"aeses In the trlal. Interestingly,~. gayanus had the highest DM yleld (1 .2 tona ha-1 ) during the 7-month dry season(Singh and Chatterjee, 1965). On ,an annuat, basis U produced 9 to 10,kg DM ha-1 mm-1 ralnl'aU. 'In en analysls al' severat experimenta in Nigerta and Camel\"oon, , ~. gayanus 'grown at near optlm~fe,.ttHty yielded approximately 8• to .' '?! kg DM ha\"'~ mm-1 ralnfa11 ~n 4 to 5-month rainy s~alilons(Barrautb. '1973;: Haggar¡ .1975). In BraZl1 EmrtCQ-(1972) reported fresh weight , / ' , ' yietds whlch, when calcutated on the basis 01' 25'Yo'to 30% DM (se., 6-montn ~tny seasons.. . \"In Colombia(CIAT, 1918; B. G~f, personal ccmmunlcetton) ~. f gayanus grown in assoclatlon wlth legumes on an tnfertlle Ultlsol wtth 90 kg P20s ha-t yletdedap,,~xl~ately 11 kg DM he-t m\",,-f, r.alnfall.The cornpanton Ingumes ~Ietded an average of 3.4 kg DM: \"a-1 mm\"\".' ra tnfa n. ' . In cornpartson, Hyparrhenia ~ ani:! the same assoetated tegl:lmes yielded 9 ancl 4.5 kg DM ~a-1 mm-1 ralnfan, respectivaty.These hlgh vatues or water use efflciency uncler relativa 16w fertility may be the resutt or 10lI'l water loss due te deep drainage ancl runot'f beCause or the bimodal distribution of rainfall.Haggar (f970) ,reported maximum c~p growtn rates in Hghtty rertltlz'lId~. gayanus pAstures 01' sUghUy over 32 kg DM ha-1 day-1 rol\" at .1east a month prior te stem etongatlon.The abiUt:y of'~. gayanus te remaln green throughout muen of the ,16 11 dry soason then provlda an \"early blté\". at the beglnning.ol' ttie rainy season Is ene 01' its most important agronornic characterlstlcs(Bowden. 18 1963a; Bogdan, f977). Nevar~.ess, only onestudy has bean conducte< 11l on lts roet system(Bowden, 1963b•)., ¡Ilondropogon gayanus val\". 20 btsquamulatus was gr\"OWn as spaced. plants at Kampala. Uganda. Three 21 morphologlcal classes 01' roets were identlrled. dlstany~ u_Uy less then 0.5 mm dlameter. ancl. . Z3 extend lateraUy over a meter I'rom the planto Cord roots are about . . . ' 1M 2 mm in d,lameter. are sParse ly branched ~ make an angle or 30 a te 40~ 25 wtt/:l the sciU'surface, and a~ setdom mor,e than 0.5 m ln leng~. 2G Vertical roets resemble f'ibr,OÚ$ roots except thet they are sparsely , . ' . "},{"text":",' 1 Hagga,. (1970) studied yleld, yleld components and quallty parameters In unferttliZed and lIg!1tly fertillzad~. gayarius varo bisquamulatus swards growing ,unlnterruptedly (ungrazed and uncut) durlng both we~ ánd dry seasons In Shika. NIgeria. Ourlng the 1964 'Wet season sta :\"Idlng c:rop OM on unfertl1ized plots increased SlgmoidaUy to 3.9 tons, ha -1. 'Durlng the followlng dry season thEi standing crop , nevel\" dropped batow 2.8 tens ha-ti however. CP dropped frcm over 6% \" at the beglnnlng ;)1' the wet sesson. to approxlmately 4% during the perlad of rapld growth in ,the middle of the wet seas,on, 'te less'l:I'lan 1.5% In the 'I'ourth month 01' the, dry season. During the 1967 w.et aeasor analysls of ylelc\".c:omponents showad that the pereentage 01' green teál'In the total dry rnatter ranged i'rcm about 60% before stem elongatlon te about 25% at ftowerlng. Thts was ac:compalned by a drop In the CP 21! content ol'!:he éntlre plant from about 4.5% durlng !:he ,rainy season te 21 3.0% In the sec:ond month 01' the dry season. During the same perlad 22 the CP 01' the gresn teat c:omponentl\")ever dropped be.low 5.5%. '23Bowden (t953a), cites reports that In a 2-year •. 12-varlety24 palatabtuty ,trlal lri Nlgerla.,e.. gayanUs ranked hlghest In pl1latabtllty 25 tollowed by Panlc:um colorntum. !!. maxlmum and 1:. eurpure\\n1 • . 26 In a 'prel'erenee tr:-Ial In Ghana ca~t~e •. sheep. and -goats grazed a 27 total 01' 12 major gress!'lpec:~es~ AU lI~stoc:k showedf)reference tor,-. 1:. maximum. Setaí-ia sphacelata and!!.: decumbens, (Tetteh. 1974). "},{"text":" ~------------~----~--~~--------~--~ .' , • "},{"text":": . . . . Socie!:y @atany); 58, 509-519 •. "},{"text":". 1 . outUne 01' Ita biolog,y.' ,Journal'of Ecology. 52, 255-2.71 •... Sowde!\", S.N. (1964~) Studies. on AndroPogon gayanus Kunth • IV. A note on the eXternal ligule and ligule or Andropogon gayanus var •. sqUamulatus (Hochst •. ) Stapr. Jouma! Qf the, Llnnean Society (Sotany), 59, 77-80. Sowden, S.N. (1971) Studles on Andropogon gayanus Kunth. VI. T~e leal' nactades 01' ..o.ndropogon gayanus val\". bisquamulatus (Hochsto) Hack. (Gramineae). Botanleal ,Journal or the Linnean Society. 64, 77-80. l Chattérjee. B.N. (1964) .At Sabour. Sadab,ahar ls firSt among fórage . Indlan ¡:::\"armlng. 14. 17-20. Chatter.jee. S.N.~ Singh, R.O. (1968) Gr6wth analysis 01' perannial , . grasses in thé troplcs in India. 4. Changes in tiller populatlon , In grass swards • .Al1ahabad Farmer. 42, 65-73. Egunjobt. ,J. K. (1974) Ory mattar. nitragen and mineral element .:Ilstributiol ,n an unburnt savanna during the year. Oecologla plantarum, 9. 1-10. Emrich, E.S. (1972) Competi~o entre Cinco gramineas fórragelras , , . para a I'ormac¡:!l'o de' pastagens em solo de cerrado. (Performance 01' flv EJ I'orage grásses used .,In ' pastura establishment In Cerrado , . SOiU. .A.r~IS lIa Reuniao Srasilelra de Cer~dos~ •1~67.• Sete Lagoas. MoG •• 2()9,-221. 34 Evans. L. T. (1964)' Reprc:iductlon o In Grasses and grass lands. 25 ~ \" London, UK¡ Maem,lIan; 1'26-153. i 26 Faster, W. H~ (1962) llÍ\\iestlgatlonS preU~inarY to the productlor.\"l 01'2'1L..._....:........:C:;:u:.;l.:,t:.;i v;,;:a:.:r..:s::,. ..:o¡;\"F..,¡.A¡¡¡¡,cn=d=r:!:!o:!:!:!!0'2=..,;¡¡o=nL.g¡!'i!ia!;!¡M.=:s='nu~S:..:.:-..:E;.:\" u:;:;o~h:.;,v¡.:.:tt i:;¡c~.?:.!J:\"':\".!'.L.: .4:::,' 7:..-::,:5::::2:::.:,. _ _ ......,-1•. . "},{"text":" ,2 gayarY..Is. Ory'ÍTlIltter yie\\ds In the flrst year are hlg~r when the gras.s Ory Matte,. Yield and Water Use Eff'\\clengt~6The reported dry matter ylelds 1'01\" /!lo. gayarY..IS ra,nge f'rom less,7 than 3 (Hagga,.. 19eá)t~ oval\" 1,7 tona OM ha-1 yr-1 (CrAT;> 1979). In 8 mature stands impo¡\"ta~t yield-detel\"'l'Tltnlng f'actors appe¡¡lr to be prevlO\\.i -: 3 ls sown broadcast. but establishment. in rows shows a stlght advaritage -: 3 ls sown broadcast. but establishment. in rows shows a stlght advaritage 4 af't:er the f'irst yaa,.. 4 af't:er the f'irst yaa,.. recom- recom- 16 menda aowtng 1.2 to 2.5' cm dEiep on weU preparad seedbed. Sowlng 16 menda aowtng 1.2 to 2.5' cm dEiep on weU preparad seedbed. Sowlng 17 rates depend largetyon aeed 'f'ertttUy •. Bogdan (1977) recommends 17 rates depend largetyon aeed 'f'ertttUy •. Bogdan (1977) recommends 18 sowlng at least 45 kg ,uncleaned seed ha-1 Ir quaUIy la unknow~. A total 18 sowlng at least 45 kg ,uncleaned seed ha-1 Ir quaUIy la unknow~. A total 19 01' 2 kg puregermlnatlng aeed ha:- ' ls pi\"Obably sufflclent (.J.E~ Ferguscr. 19 01' 2 kg puregermlnatlng aeed ha:-'ls pi\"Obably sufflclent (.J.E~ Ferguscr. 20 personal communication). 20 personal communication). 2l Since~. gayanus. Hke many perennlat gr'asses. produces Uttle 2lSince~. gayanus. Hke many perennlat gr'asses. produces Uttle 22 :' forage during the wet season In whld1 It ,la s,own, ti: can be sown with 22 :' forage during the wet season In whld1 It ,la s,own, ti: can be sown with 23 annuat companlon crops té) lncrease th\\9 econcmlc yield durlng the 1'lr~t, 23 annuat companlon crops té) lncrease th\\9 econcmlc yield durlng the 1'lr~t, , , ,, 24 year. '[1\"'1 Nlgerla (Haggar, ,1969). malze and a~eans are more sutt- 24 year. '[1\"'1 Nlgerla (Haggar, ,1969). malze and a~eans are more sutt- "},{"text":" 1 system conststed 01' 50%. fibrous roots. 40% cord roots. and .10% :8 ve'rUecal roots (by welght). Ourlng the dry seasqn on a deep Oxisol In Carlmagua. Colc:rnbta .. .' .' , ' . 3 . . . , ' . 3. .. -4 ~. gayanus. tlke Brachiárla decumbelÍS. conttnued te extract water -4 ~. gayanus. tlke Brachiárla decumbelÍS. conttnued te extract water 6 I'rc:rn the deeper layers 01' thá soil prof11e leng~r than -,=. maxlmum 6 I'rc:rn the deeper layers 01' thá soil prof11e leng~r than -,=. maxlmum 6 (J.M. Spain. personal cc:rnmt.ntcation). Ouring the dry seasen It 6 (J.M. Spain. personal cc:rnmt.ntcation). Ouring the dry seasen It .7 produc:ed slighUy graater CM ylelds than!!. decumbens (P. Sánchez. .7 produc:ed slighUy graater CM ylelds than!!. decumbens (P. Sánchez. 8 personal communlcatiop). Two months into the dry seasen both lts 8 personal communlcatiop). Two months into the dry seasen both lts lB Sánchez, pereonal communlcatlon); hawever. with O.6-nleter r•QW lB Sánchez, pereonal communlcatlon); hawever. with O.6-nleter r•QW 19 spaclng and only three cuts per yea!\"'~. gayanus ylélded slightly more 19 spaclng and only three cuts per yea!\"'~. gayanus ylélded slightly more 200M tlÍan!!. decumbens or -,=. maxlmÚm (F. MC,Ue!\"'. personal 200M tlÍan!!. decumbens or -,=. maxlmÚm (F. MC,Ue!\"'. personal 21 communtcation). These data agree wUh those 01' Barrault (1973) whlch 21 communtcation). These data agree wUh those 01' Barrault (1973) whlch 22 Indicate thiat 10000ar rrequer:lCy 01'• C\\Jttlngfavors total OM ac~ulatlon 22 Indicate thiat 10000ar rrequer:lCy 01'• C\\Jttlngfavors total OM ac~ulatlon 23 ~n ~ gayarus. l.lght lnterceptlón \\s probaply timits crop grawth rata 23 ~n ~ gayarus. l.lght lnterceptlón \\s probaply timits crop grawth rata undar undar "},{"text":" , Andropogon gayar.lus ~nth Is a large tufted grass species i:hat 15 highly productive. moderately'nutritious In pure stand without N fertillzation. and highly palatable to aH classes of lvestock. It 'is easil,Y establlshed and Is easily eHminated by ploughing. It is very ',7 tolerant of p~oblem soils. including Oxisols ancj Ultisols which are low.: In P and have high levels of Al saturation. It is resistant to burning anc! drought stress arid is known for.-,its production of green forage throughout. the dry season and its r?pid recuperation after burning and uppn resumption oF the ra:,'Y season. . It appears to be best adapteé..••te , monsoonal cllmates at elevatlons below 2000 m with dr'y seasons of 3 13 to 5 (01\" more.) months and annual ralnfall above 750 mm. Urider 14 moderate to high ferttuty annual DM production ranges from 9 to 11 kg: • \" gayanus hay;to lntake aÍ\"ld dlgas.tlbtUty In sheep was demonstrated by . . . Haggar aOO Ahmed (1970) aOO !-/aggar (1972)': Restrictlng the amOunt of feed on ol'l'el\" reduced dl\"y matter digestlbUlty. presumably because . '1 the sheep were forced•to consume more 01' the uOOigestlbhi stem . . . : U productng cOntlnua1 yeung gr'DllVth •(Ratns. aOO Fester. 1958; Barrau1i:, 20 1973), ando Incluslon of a legumtnous assoctate 01\" supptement. (eIAT., 21 1978; Haggar. 1972). 22 Response to Ferttllty. 23 The response 01' cr.ops to l'erttuzer N ts dlff'icult to .compare . . 1 declines I'rom 80% te 50% In the I'lrst b'ear. to 30% in the third year .' 2 ard to zero in 4 to 6-year-old seed. .. ' '•8 In Colombia ylelds 01' grac!,ed seed 01' 40% purity has varled I'rom 30 to 300 kg ha-1 wlth a mean graded seed yield 01' 120 kg ha-1 • 4 5 Germination 01' untreated pure seed h~s been as high as 65% at 9 months 20 • 6 :7 8 9 : 10 11 12 13 14 15 16 .. 17 18 lE 20 21 .22 24 (J.E. Fergus~. personal communlcatlon). These yields are eonsiderably better than those reported elsewhere and ls probably Indicativa 01' tha Importan ce of' eli.mate ¡n'seed •production. Ylelds 01' 200 kg/ha of' graded seelng testing 40% international RUrity ard 50% '1ermination (I..e. 20% Pure Live Seed (PLS,) content). would allow seeding rates 01' 10'kg ha-1 of such seed (providing 2 kg ha-1 of PLS). Thus. a multiplication rate 01' approxl.mately 20 (20 ha seeded 1'01'\" each'h:t harvested) Is feaslble. . •. . . .. , 15 DM ha-1 mm-1 rainFaH •. It is reported te associate well wlth a 16 number of legumes. 'and the few avaitable data indicate that animal 17 gains on etther pure stands 01\" on mixtures with legumes are Far 18 ~uperior te those on' native pasture. 19 Seed production varies With location. but a ratio of 20 ha planted 20 per ha hal\"Vested seems ppssible to attain •. In addition, A. gayanus 21 adapts wett te companion crops, and 900d possibllities exlst For the 22 development oFvery low de~iI:Y. mlnimum Input planting techniques 24 belween sltes aOO'between .vea,.. ,\" 23 23 whl\"ch take advanlage of selF-sown seed. • \" gayanus hay;to lntake aÍ\"ld dlgas.tlbtUty In sheep was demonstrated by . . . Haggar aOO Ahmed (1970) aOO !-/aggar (1972)': Restrictlng the amOunt of feed on ol'l'el\" reduced dl\"y matter digestlbUlty. presumably because . '1 the sheep were forced•to consume more 01' the uOOigestlbhi stem . . . : U productng cOntlnua1 yeung gr'DllVth •(Ratns. aOO Fester. 1958; Barrau1i:, 20 1973), ando Incluslon of a legumtnous assoctate 01\" supptement. (eIAT., 21 1978; Haggar. 1972). 22 Response to Ferttllty. 23 The response 01' cr.ops to l'erttuzer N ts dlff'icult to .compare . . 1 declines I'rom 80% te 50% In the I'lrst b'ear. to 30% in the third year .' 2 ard to zero in 4 to 6-year-old seed. .. ' '•8 In Colombia ylelds 01' grac!,ed seed 01' 40% purity has varled I'rom 30 to 300 kg ha-1 wlth a mean graded seed yield 01' 120 kg ha-1 • 4 5 Germination 01' untreated pure seed h~s been as high as 65% at 9 months 20 • 6 :7 8 9 : 10 11 12 13 14 15 16 .. 17 18 lE 20 21 .22 24 (J.E. Fergus~. personal communlcatlon). These yields are eonsiderably better than those reported elsewhere and ls probably Indicativa 01' tha Importan ce of' eli.mate ¡n'seed •production. Ylelds 01' 200 kg/ha of' graded seelng testing 40% international RUrity ard 50% '1ermination (I..e. 20% Pure Live Seed (PLS,) content). would allow seeding rates 01' 10'kg ha-1 of such seed (providing 2 kg ha-1 of PLS). Thus. a multiplication rate 01' approxl.mately 20 (20 ha seeded 1'01'\" each'h:t harvested) Is feaslble. . •. . . .. , 15 DM ha-1 mm-1 rainFaH •. It is reported te associate well wlth a 16 number of legumes. 'and the few avaitable data indicate that animal 17 gains on etther pure stands 01\" on mixtures with legumes are Far 18 ~uperior te those on' native pasture. 19 Seed production varies With location. but a ratio of 20 ha planted 20 per ha hal\"Vested seems ppssible to attain •. In addition, A. gayanus 21 adapts wett te companion crops, and 900d possibllities exlst For the 22 development oFvery low de~iI:Y. mlnimum Input planting techniques 24 belween sltes aOO'between .vea,.. ,\" 23 23 whl\"ch take advanlage of selF-sown seed. 25 25 26 26 2'7 2'7 "},{"text":" S.N. (1964a) StuI;Iies on Andr\"opogpn gayanus Kunth. n. An outllne o: the mOl\"phology and anatomy ol' Andr\"Opogon gayanus C'IAT (1978) Seel' Productton Program Annual Report 1977. Centro . . . Internacional de Agrlcultul\"'S. Tropical, Call, Colombia, i:a press. C'IAT (1978) Seel' Productton Program Annual Report 1977. Centro . . . Internacional de Agrlcultul\"'S. Tropical, Call, Colombia, i:a press. Atkln, R.K.; Sartan, G.E.; RebIASon, O.K. (1973) 'Effect of root-• Atkln, R.K.; Sartan, G.E.; RebIASon, O.K. (1973) 'Effect of root-• growing tempera.tures on growth substances in xylem exuda te ol' growing tempera.tures on growth substances in xylem exuda te ol' Zea mays. 'Journa,l 0'-Experimental•Sotany. , 24, 475-487. Zea mays. 'Journa,l 0'-Experimental•Sotany. , 24, 475-487. Sarrault. J. (1973) La recherche l'ourrag~re au Nol\"d-cameroun. Sarrault. J. (1973) La recherche l'ourrag~re au Nol\"d-cameroun. ,'1 Productlon ei: valeur aHmentai,re de quelques fourrages tocaux ,'1Productlon ei: valeur aHmentai,re de quelques fourrages tocaux (Travaux menés par l'IRAT.de 1965 a 1971). (FOrage crop (Travaux menés par l'IRAT.de 1965 a 1971). (FOrage crop researCh In Narth Cameroon. P¡\"'oduction and food value 01' some researCh In Narth Cameroon. P¡\"'oduction and food value 01' some 10 la«a1 l'orage (work ca¡:'~ied' out ~ IRA 1-I'~ 1965 to 1971») • 10la«a1 l'orage (work ca¡:'~ied' out ~ IRA 1-I'~ 1965 to 1971») • 11 L'Agronomle Tropicale\" Parls, 28, 173-188. 11L'Agronomle Tropicale\" Parls, 28, 173-188. 12 12 13 13 14 14 15 Al'rlca. Proceedlngs o, the ,11 th Internatlonal Grasslands 15Al'rlca. Proceedlngs o, the ,11 th Internatlonal Grasslands 16 CongreSs, Surfers Paradl.Se, p. 1-3. 16CongreSs, Surfers Paradl.Se, p. 1-3. 1'1 Bowden, S.N. (1963a) Studles onAndrópogon gayanus Kunth. 1'1Bowden, S.N. (1963a) Studles onAndrópogon gayanus Kunth. 18 l. The use of Andropogon gayanus' In agrlculture. E::mplre 18l. The use of Andropogon gayanus' In agrlculture. E::mplre ,19 Journal ol' Experimental Agr\"leulture. 31, 267-273. ,19Journal ol' Experimental Agr\"leulture. 31, 267-273. 20 Sowden S. N. (1963b) -r:he root distl\"lbutton 01' Andr\"opogon gayanus 20Sowden S. N. (1963b) -r:he root distl\"lbutton 01' Andr\"opogon gayanus 21 var,_ blsguamulatus • East Arrican Agricultural a,nd FOr\"estry 21var,_ blsguamulatus • East Arrican Agricultural a,nd FOr\"estry 22 ,Journal.¡ 29, ,157-159. 22,Journal.¡ 29, ,157-159. : : 27 27 "}],"sieverID":"b873c362-9223-4ef1-999c-1da011f56bb0","abstract":"Beet' ls a staple roed In Latln Amel\"lea. About 70\",{. of Its beet' pl\"'oductlon.ls In tl\"opU::al reglone. Tropical America has á hlgher pel\" , , .caplta beef' cattle populatlon ttan Ner\"th Amerlca. Western Eul\"ope. ór• , ."} |
