UTILIZATIm~ OF PHOSPHATE ROCK IN TROPICAL SOILS OF LATIN AMERICA\

W E FENSTER AND L A LEON

11 March 1978

I F D C

INTERNATIONAL FERTILIZER DEVELOPMENT CENTER

C 1 A T

CENTRO INTERNACIONAL DE AGRICULTURA TROPICAL

CC~C0TI BIBLIOTECA

2 4 ecT 1983 5[}515

UTILIZATION OF PHOSPHATE ROCK IN TROPICAL SOILS OF LATIN AMERICA

W E Fenster and L A León *

The d~reet use of phosphate roek (PR) as a phosphorus {PI

fert~l~zer ~s not a new coneept ~n e~ther the temperate or trop~-

cal areas of the world The great ma)Or2ty of the PR exper2-

ments, however, have been condueted ln temperate ellmates on

s021s wlth pH valves of 5 5 or aboye The volum2nous amount

of llterature wou1d lnd~cate 2n general that a dlrect relat~on-

sh~p eXlsts between flneness of part~cle Slze and yleld response

Most of these experlments were usually condueted from a sOll

fertlllty standpolnt whereby a partlcular PR was applled to a

part~cular s021, and yleld responses were noted It has been

po~nted out that thlS emplr~cal approaeh had var20US l~m~tatlons

not only beeause of the tremendous varlablllty between s021s but

al so the large varlabl12t~es between PRs As a consequenee, the

experlmental results varled markedly from experlment to exper-

2ment, thus mak2ng the pred~ctlb212ty of PR effeetlveness as a

P fertlllzer almost ~mposs2ble to ascerta2n In addltlon, the

reslQual value of PR was not 2n most 2nstances determlned as

most of the experlments were deslgned for only one to two years

In recent years, however, laboratory studles have been

made wlth the Ob)eet2ve of charaeterlz2ng PRs froID a P

* Members of the Internatlonal Fertlllzer Development Center, Phosphorus Program,statloned at CIAT 8021 Fert2l1ty and 5011 Chemlstry Spee2allsts, respeetlve1y Paper presented at Phosphate Rock 8emlnar ln Teehn~on - Israel Instltute of Teehnology, Ha~fa, Israel Narch 1978

- 2

ava¡lab~lity standpoint (12, 28, 35) Also long-term exper~-

ments have been set up ~n trop~cal Lat~n Amer~ca to determlne

the resldual value of the rock sources Th~s, comb1ned w~th a

thorough and mean~ngful so~l analys1s should help to clar1fy

the PR effect~veness from a general1zed fertlllzer recornmenda­

t~on standpo1nt

The Ob)ect1ves of th~s paper wlll be to rev~ew the so~ls

and phosphorus fert~l~zer prob1ems ln the aCld OXls01s, U1tl­

s01s and Incept1sols {target areal of trop~ca1 Latln Amer1ca,

se1ect1ve1y reVlew the llterature, state the research obJec­

tlves and attempt to layout a research program to meet those

Ob)ect1ves

SOILS AND PHOSPHORUS PROBLEMS IN TROPICAL LATIN N1ERICA

The se~ls ~n the target are a of trep1cal Lat~n Amer~ca are

prlmar1ly OXlsols and Ultlsols (Flg 1) These so11s are gener-

ally med~um to f~ne textured, present an aC1d react~on of frem

4 O to 5 5, and contaln only about 200 to 600 ppm total P

Ava1lable P ~s also very 10w ln these sOlls, rang~ng only froro

abeut 1 to 5 ppm, regard1ess ef extractant used It lS qU1te

ObV10US that w~thout add~tlons of P ne~ther arable nor forage

crops can be grown effectlvely Due to the extremely ac~d con­

d~tlons, these sOlls are also hlgh 1n free lron and alumlnum

oX1des and hydroxldes WhlCh tend to rapldly flX large ameunts

of P when lt lS applled ln soluble forms such as slngle (SSP)

or trlple superphosphate (TSP) Although P lS generally the

- 3 -

most l¡m¡ting element, other nutr¡ent defic¡encies of n¡trogen,

patass1um, sulfur, calc1um and magnes¡um are common (12, F¡g 2)

In addit¡on to these nutr¡ent management problems, there ¡5 also

the problem of alum¡num and manganese toX¡C¡ty

From a phys¡ca1 standpo¡nt, the so¡1s wh¡ch have potent¡al

for arable and forage crop product¡on, ¡n general, possess ex­

cellent structure, good ¡nf¡ltrat¡on capac¡t¡es and are well

dra¡ned Accordlong to Sánchez (45), "the excellent structure

of these so¡ls ¡5 caused by pr¡mary part¡cles be¡ng aggregated

¡n very stable sand-s¡zed granules The¡r hlogh 5tab¡1¡ty ¡S

assoc¡ated w¡th hlogh clay content ana cement¡ng or coat¡ng of

amorphous ¡ron and alum¡num ox¡des" He further states that

the organ¡c matter content ¡S also d¡rect1y assoc¡ated w¡th the

aggregate stab¡l¡ty It ¡S clear that the phys¡cal propert¡es

of these trop¡cal Lat¡n Amer¡can sOl.ls w¡ll not present maJor ,

problems ¡n most crop product¡on schemes

One of the ma¡n l¡ml.t¡ng factors ¡n ¡ncreas¡ng crop pro­

duct¡on ¡n trop¡cal Lat¡n Amer¡ca would appear to be the h¡gh

cost of fert¡l¡zers, espec¡ally those conta¡n¡ng hlogh amounts

of ava¡1able P Th¡s loS pr¡mar¡1y due to the hlogh cost of man-

ufactur¡ng wh¡ch results from the h¡gh ¡nput costs of sulfurl.c

and/or phosphorl.c ac¡d used ¡n the aCl.dulat¡on process Trans-

portat¡on costs are also hl.gh G¡ven the fact that hl.gh rates

of these P fert¡l¡zers are requ¡red to be effect¡ve, ¡t ¡S easy

to see why ¡mmed¡ately ava¡lable forms of P fert¡!¡zers are not

used on most arable or forage crops, except those of h¡gh mone­

tary value such as pota toes and other vegetable crops

- 4 -

The d~rect use of PR or sorne of its low-input altered prod­

ucts would seem ta present a log~cal approach to take ~n over­

com~ng the monetary and so~l chem~cal constra~nts ~n crop pro-

duct~on wh~ch have been ment~Dned prev~ously Over the years

many hundreds of PR tr~als have been conducted to ~ncrease crop

product~on These exper~ments lend cred~b~l~ty to the ~dea

that PR or ~ts low-cost altered products could be used to ~n­

crease crop prDduct~on both from short- and long-tarm v~ewpo~nts

G~ven the amounts of exchangeable and nonexchangeable ac~d~ty

~n these trop~cal so~ls, ~t would seem natural that PR could

and should be used ~n sorne form to make ~ncreased arable and

forage crop product~on an econom~cally feas~ble real~ty

REVIEW OF THE LITERATURE

The authors recogn~ze and have rev~ewed much of the l~ter­

ature perta~n~ng to the use of PR as a source of P for crops ~n

the temperate areas of the world Most of the l~terature c~ted

here, however, w~ll be from research conducted ~n trop~cal Lat~n

Arner~ca as our proposed research w~ll be focused ~n th~s area

General Phosphorus and So~ls Rev~ew

In a rev~ew chapter on P, Kamprath (34) states, "the h~gh­

ly weathered so~ls, Ox~sols and Ult~sols of the trop~cs along

w~th Andosols, are generally very def~c~ent ~n phosphorus Many

of the so~ls f~x larga quant2t2es of added phosphorus There-

fore, w~thout the appl2cat~on of phosphorus, susta~ned crop

- s -

product~on at h~gh y~elds ~s not possl.ble". After a rather ex­

haustl.ve rev~ew of crop responses to phosphate fert~l~zat~on ~n

the trop~cs, Kamprath (34) further ~nd~cates that, "Rates of

phosphorus on def~c~ent so~ls generally g~v~ng opt~mum y~elds

were 100 to 150 kg P20S/ha for corn, soybeans, sugarcane and

forages, 120 to 240 kg P 20 S/ha for wheat, 120 to 180 kg p 2os/ha

for potatoes, and 60 kg P20 S/ha for r~ce"

Fassbender et al (24) ~n a greenhouse study w~th tomatoes

as the test crop on 110 d~fferent so~ls of Central Arner~ca showed

that most of the so~ls stud~ed (66%) were extremely def~c~ent

~n P and only 15% contaLned an adequate supply In another

greenhouse study w~th tomatoes, Fassbender (2S) showed that 96%

of the appl~ed monocalcLum phosphate (MCP) was transformed ~nto

~ron and alumLnum forms after 8 weeks wLth a P-def~c~ent Incep­

tLsol, ~n the Colorado ser~es (pH KCl 4 6)

In characterLzLng sorne of the maLn Ox~sols and Ult~sols at

the QULILchao and Car~magua experl.ment statl.ons, Ln ColombLa,

and at the Cerrado Center statl.on, Ln BrazLl, Le6n and Sánchez

(12) found sOLl pH values from 4 1 to 4 9 and percent alumLnum

saturatLon ranges from 64 to 82 (Table 1) The avaLlable P

(Bray 11) levels were extremely low, showLng values from only

trace amounts to 1 8 ppm ~n both surface and sub-samples Also,

us~ng a Qu~l~chao 501.1 ~n a greenhouse MLss~ng element trLal

w~th Centrosema plum~erL, Gualdr6n, Le6n and Sánchez {12} found

thLS so~l to be severely def~cl.ent l.n P as well as sulfur, Doron,

and to sorne extent calc~um (FLg 2) In further studLes these

- 6 -

LnvestLgators lndlcated that a 5011 test of about 3 ppm P (Bray

11) was a critical level for achlevlng 80% of maxlmum Yleld

wLth both PanlcQm maximum and a Centrosema hybrld (Flg 3) It

was also suggested that arate of about 240 kg p2oS/ha would

be needed to satlsfy thlS requlrement

In order to characterlze the P flxatlon capacLty of the

BrasLlla, QUlILchao and Carlmagua experlment statlon sOlls, Le6n

and Sánchez (12) ran P flxatLon lsotherms (Flg 4) USlng a

o 2 ppm P ln Solutlon as a crltLcal level, lt took 620 to 7S0

ppm P for QUlllchao and BraSllLa and about 350 ppm for Carlma­

gua to achLeve thls, thus lndlcatlng the extremely hlgh flxa­

tlon capaclty of the5e sOl15

Dlrect Appllcatlon of Phosphate Rock to SOL15

The dlrect appllcatLon of PR to temperate sOll condltlons

lS well documented ln the lLterature It lS also well recog-

nlzed that ~uch of the research and the resultlng contrlbutLons

to the understandLng and use of PR as a P source for plants,

was conducted ln Europe, the unlted States, and other parta of

the world (3,4,5,7,13,18,19,21,22,29,33,42,44,49)

In troplcal Latln Amerlca the lnformatlon on dlrect appll­

catlon of PR lS more 11mlted, neverthe1ess, lmportant and appll­

cable studles have been and are belng conducted ln severa1 of

the countrles

lnvestlgatlons

ThlS sectlon wlll be devoted prlmarlly to these

- 7 -

Character~z~ng Phosphate Rocks

Over the years it has been we11 understood that f~neness

of partlc1e Slze of the PR and so11 reactlvlty were extreme1y

lmportant ln predlctlng the value of PRs (3, 13, 19, 33) Slnce

lt was genera11y and erroneously assumed that most were fluor­

apatlte, varlable agronomlc responses ln fleld and greenhouse

stud1es were usua11y attrlbuted to partlc1e S1ze of the rock

and/or d1fferent s011 character1st1cs Lehr and McClellan (35)

state that, "new lnslght lnto the composltl0n of phosphate rocks

was obta1ned recently from characterlzatl0n stud1es WhlCh showed

that the composltlons of thelr apatltlc phosphate mlnerals var1ed

markedly Wlth few exceptlons, the apatltes were not fluor-

apatlte, but belonged to the ser19S of carbonate apatltes ln

WhlCh P04 lS replaced by C03 and F, and Ca lS replaced by Na

and Mg ln the fluorapatlte structure Chem1cal react1v1ty of

the apatlte 1ncreased as the degree of Substltutlon lncreased"

Based on thlS the cltrate solubl11ty was redef1ned on an abso-

lute baS1S ThlS "Absolute Cltrate Solubl11ty" (ACS) 1ndex for

any g1ven rock was deflned as the rat10 of 1tS c1trate-soluble

P20S to the theoret1cal P20 S content of 1tS part1cular apat1te

compos1t1on (3S) Work1ng w1th 50 representat1ve PRs, Lehr

and ~1cClellan showed that the ACS J.ndex "Correctly assoc1ated

P20S solublllty w1th the k1nd of apatlte supply1ng the P20S'

and not merely the amount of apatlte, or P20S grade of the

phosphate rock" They further showed a hlgh degree or correl-

atl0n between the ACS 1nd1ces of the rocks and agronomlc re-

sponse to the1r P 1n greenhouse stud1es Hore recently,

- 8 -

Hammond and León (12) hav~ shown that the relative ava~lab~l~ty

of ~ fram PR aources correlatas well w~th the c~trate-soluble

P content of the material when expressed as "percent of the

rock" rather than "percent of total P20 S ~n the rock" In a

greenhouse study w~th Pan~cum max~mum, the researchers also

concluded that the degree of correlat~on was h~gher when h~gher

rates of the var~ous PRs were appl~ed (F~g 5)

The character~zat~on of the PRs has really ~lluc~dated

many of the here-to-fore errat~c appear~ng research results

w~th the mdny d~fferent rocks Even more ~mportantly, the rel-

at~ve agronom~c effect~veness (RAE) can be pred~cted for the

var~ous PRs For example Gafsa (Horocco), Sechura (Perú), and

North Carol~na (USA) rocks are cons~dered h~ghly react~ve, Hu~­

la (Colomb~a) and Flor~da (USA) med~um react~v~tYl and Pesca

(Colomb~a) and Tennessee (USA) are of low react~v~ty Hammond

and León (11,12) ha ve conf~rmed th~s pred~et~b~l~ty w~th e~t­

rate soluole P ~n the total roek w~th both greenhouse and f~eld

stud~es (Table 2)

Greenhouse and F~eld Invest~gat~ons w~th Phosphate Rock

A number of exper~ments have been condueted ~n trop~cal

Lat~n Amer~ca us~ng the d~reet appl~cat~on of PR Although

many of the results have be en qu~te var~able, reeent works ~n

Braz~l and Perú by North Carol~na State Un~vers~ty (40), and

~n Colomb~a by the Internat~onal Fert~l~zer Development Center

(IFDC) and CIAT (9,10,11,12,28) have shown very encourag~ng

results

- 9 -

Alvarez et al (1), ln several exper¡ments w¡th sugarcane

on acid soils in Sao Pau¡o, Braz¡l, us¡ng var¡ous sources and

rates of P showed that four naturally occurr¡ng PRs gave 10 to

28 percent y¡eld Lncreases whLle other more ava¡lable phosphate

fertLlLzers gave 3S to 49 percent y¡eld ¡ncreases In another

serLes of experLments Ln Sao Paulo w¡th corn, M¡randa et al (41)

showed that three PRs from Brazll gave yLeld ¡ncreases of from

37 to 71 percent of that atta¡ned wlth ord¡nary superphosphate

over a two year perl0d

In 1969 s¡gn¡f¡cant exper1ments w¡th PR were also ¡n¡t¡ated

by Le6n et al (37) ¡n several geograph¡c areas of Colomb¡a on

Ox¡sols, Ult¡sols, and sorne ¡ncept¡sols Vary¡ng rates of PR,

bas¡c slag, and SSP and TSP were compared us¡ng oats for forage,

several forage grasses, peanut, corn, r¡ce, and on¡ons as the

test crops On selected treatments of 200 kg P20S/ha for TSP,

Turrneque (Pesca-l¡ke) rock and Flor¡da rock, w¡th 3 cutt1ngs of

Pen¡setum clandest¡num, the researchers found that all forms of

P gave s¡gn1f¡cant y¡eld 1ncreases over the check and that TSP

was sl¡ghtly ¡nfer10r to both forms of PR S1rn¡lar broadcast

treatments at two other locat¡ons w¡th d¡fferent grasses showed

no S¡gn¡f1cant yleld 1ncreases after 5 to 7 cutt¡ngs, regardless

of the so urce of P At other locat¡ons wlth Dactyl¡s glomerata,

L only s11ght y1eld ¡ncreases w¡th TSP were noted When oats

(2 crops) was the test crop 200 kg P20 S/ha gave s1gn1f¡cant y¡eld

¡ncreases w1th TSP and Turmeque rock In th¡s same exper1ment no

1ncreases were rea11zed w1th Plor¡da rock W1th on10ns, appl¡ca­

tLons of 100 to 200 kg p2oS/ha e¡ther broadcast or row appl¡ed

- 10 -

gave s~gn¡f~cant y~eld ~ncreases regardless of tne P source

In the Llanoa Or¡entales reg~on of Colomb~a w~th corn, the

response to P was hLghly sLgnLfLcant (FLg 6) Although the

results var~ed the f~rst year, Ln the second and thLrd years,

Turmegue and FlorLda PRs were egual to and Ln sorne cases super-

Lor to T5P León et al (36,37) concluded that Ln the hLghly

aCLdLc P defLcLent sOLIs of ColombLa, almost all crops showed

sorne degree of response to applLcatLons of PR

In the Cerrado of BrazLl, North CarolLna 5tate UnLversLty

and Cornell (43) LnLtLated a long-term experLment wLth varLOUS

phosphate carrLers on pastures to determLne the effect of uSLng

cheaper sources of P In~tLally the two hLghly soluble PRs,

Gafsa (Morocco) and North CarolLna, performed about as well as

55P The low reactLve Araxá PR from BrazLl was LneífectLve at

fLrst, however, after two years the avaLlabLlLty was Lncreased

sLgnLfLcantly and YLelds were comparable to other P carrLers,

LndLcatLng Lt may be economLcally competLtLve wLth tLme (FLg 7)

Rates of P20 5 used were 86, 345 and 1380 kg/ha In the Amazon

Jungle o[ Perú, North CarolLna 5tate UnLversLty (43,47) Ln an­

other ser Les of pasture experLments also showed that Gafsa, Flor­

Lda, North CarolLna and Fosbayovar (Perú) PRs were comparable

to 5SP Ln forage productLon wLth PanLcum maXLmum These exper-

Lments Ln BrazLI and Perú WLll be contLnued to assess the re­

sLdual values of the P carrLers

In the hLghlands of Perú, DavelouLs and Cano (14) conduct­

ed a serLes of P experLments wLth potatoes and wheat over a

two year perLod In comparLng 5echura rock, Gafsa rock, 55P,

- 11 -

and cornb1nat10ns of rock plus super, these researchers reported

that marginal money returns were better for the PRs than SSP

The best econom1C returns were noted w1th pota toes when 160 kg

P20S/ha of Sechura PR and 80 of SSP were app11ed (F1g 8) Al­

though the results w1th wheat were not very encourag1ng uS1ng

PR, the res1dual effect the follow1ng year w1th potatoes showed

prom1se

In Colornb1a, Howeler (9) on an aC1d,low P s01l reported

that 200 kg P20 S/ha as TSP 1ncreased bean y1elds from O 7 to

1 8 tons/ha wh11e only s11ght responses were noted w1th HU1la

and Turmeque PRs In another bean exper1ment on an aC1d,low P

Andept, Howeler, Hammond and Le6n (11) * state that, na pos1t1ve

response to appl~cat1on rates as h1gh as 400 kg P20S/ha was ob-

Although TSP produced the best response, relat1vely

soluble rock phosphates from Gafsa (Morocco), North Caro11na!

(USA), Sechura (Perú) and HU1la (Colornb1a) also gave good re­

sponses Y1elds w1th more 1nsoluble rock phosphates from Ten­

nessee and Flor1da (USA) were lower but st11l s1gn1f1cantly

better than the control The agronom1c effect1veness of the

sources followed closely the1r solub1l1ty 1n N ammon1um c1trate,

a ~ommorly used measure of ava1lable phosphate" (F1g 9) These

same researchers found s1m1lar results uS1ng the same P carr1-

ers 1n a Car1magua OX1sol w1th cassava Y1elds ranged from 18

to 2S ton/ha w1th 400 kg P20 S/ha down to 8 ton/ha on the

check Rates of 100 kg P20 S/ha also appeared very encourag1ng,

espec1ally w1th the more soluble sources of PR

* Internat10nal Pert1l1zer Developrnent Center cooperat1ng

- 12 -

Harnmonq (12, ~B),~n a greenhouse exper~ment with ran~cum

maximum grown on a Car.magua Ox~sol, reported that the h~gh re­

actlvlty PRs, Sechura and North Carol~na, were super~or to ap­

pl~cat~on rates of TSP ranglng from 50 to 400 ppm P (F~g 10)

HUlla and Pesca PRs were les s effectlve than TSP but s~gn~fl­

cantly better than the cheeks Us~ng a Relatlve Agronomlc Ef­

fectlveness sea le w~th bas~e slag equal to lOO, Sechura, North

Carollna, TSP, Hu~la and Pesca were scaled at 94, 82, 62, 41,

and 27, respect~vely (F~g 10) In a long-term f~e1d exper~­

ment at Carlmagua uSlng Brachlar~a decumbens and comparlng SlX

PR sources wlth TSP at P20 5 rates vary~ng from O to 400 kg/ha,

Hammond and Le6n (12) conclude that, "trlple superphosphate was

only superlor to rock phosphates durlng the flrst cut, after­

wards all rock phosphate sources lncreased thelr effeetlveness

wlth tlme approachlng or surpasslng the ylelds of superphos­

phate durlng the thlrd and fourth cuts (Flg 11) The overa1l

results durlng the flrst 16 months show the hlgh reactlvlty

rocks, Gafsa and Sechura, were 105 and 99% as effeetlve as

superphosphate, the medlum reactlvlty HUlla roek was 91% as

effectlve, and the low reactlvlty rocks, Tennessee and Pesca

were 87 and 88% as effectlve as trlple superphosphate" ThlS

experlment wlll be contlnued to further eva1uate the resldual

effects of the PRs, but already there appears to be opportunl­

ty for the use of the low cost, low react1vlty rocks on the

aCld sOlls for pasture productlon

- 13 -

Greenhouse and F~eld Invest1gat10ns w1th Part1al1y Ac~d­

ulated Phosphate Rock

The use oí part1a1ly aC1dulated PR may present an attrac-

t1ve alternat1ve to the use oi e1ther PR or superphosphate alone

or 1n comb1nat10n 1n the aC1d,P def1c1ent s01ls of trop1cal

Lat1n Amer1ca

~lcLean and Wheeler (40) conducted a growth chamber study

w1th German m1llet and alfalfa 1n Wh1Ch f1nely ground Flor1da

PR was aC1dulated w1th phosphor1c aC1d to the follow1ng degrees

O, 10, 20, 50, 100% TwO Oh10 s011s were l1med to pH levels

of about 6 O and 6 5 and P was added at arate of 90 pp2m

The P was app11ed both 1n bands and broadcast These re-

searchers conc1uded that, "1n general, German m1llet and alfal-

fa Y1elded about as much and conta1ned as much P 1n the t1ssue

from 10% aC1dulated phosphate as from 100% aC1dulated" "The

comparat1ve favorable plant response to the part1ally aC1du-

lated mater1al and the economy of 1ts product10n make part1al

aC1dulat1on appear to have very prom1s1ng pract1cal app11cat1ons"

Terman and Allen (48) aC1dulated Flor1da PR w1th phosphor-

1C aC1d to levels of O, 10, 25, 50, 75, and 100%, and then

granulated the result~ng mater1als to -6+9 and -35 mesh Two

exper1ments were conducted w1th corn on 50115 w1th pH values

of 6 5 and 5 6 and P was app11ed at rates of 40, 80 and 160 lbja

p The authors concluded that dry matter y1elds were d1rect-

ly related to the amount of P app11ed and the content of water-

soluble P They further noted that the conclus10n from these

- 14 -

stud~es d~ffer markedly frorn the works of McLean et al (40) anq

suggest that the reason rnay be that these researchers used un­

granulated rnater~als appl~ed at only one rate

In Colornb~a, McCorrn~ck and Galeano (38) ac~dulated Turme-

gue FR w~th sulfur~c ac~d to levels of O, 25, 50, 75 and 100%

Four pot exper~rnents were conducted w~th so~ls from the Sabana

of Bogotá and the eastern pla~ns of Co1ornb~a w~th barley as the

test crop The rate of phosphorus appl~ed was 200 kg p 2os/ha

Y~eld results showed that ~n general all levels of ac~dulat~on

were super~or to unac~du1ated PR and there were no d~fferences

between levels of ac~dulat~on frorn 25 to 100%

Howeler (10) ~n a bean exper~ment on an ac~d,P def~c~ent

Andept so~l near Popayán, Colornb~a, reported that Hu~la PR ac~d­

ulated to a level of 20% w~th sulfur~c ac~d ~mproved ~ts ef­

f~c~ency to that of TSP at rates of up to 400 kg p 20 s /ha (F~g

12) In another exper~ment a 5 1 m~xture of Hu~la PR sulfur

gave cassava y~elds wh~ch were egual to those of TSP at rates

In other exper~ments ~n Colornb~a, however, when elemen-

tal sulfur or ammon~um sulfate were added to PR and appl~ed to

the so~l, no y~eld responses were noted and ~n sorne cases y~eld

depress~ons occurred (10,27,30)

Greenhouse and F~eld Invest~gat~ons wÁth Thermally Altered

Phosphate Rock

Rhenan~a phosphates These phosphate fert~l~zers are made

by heat~ng PR, sod~um carbonate and s~l~ca to temperatures of

- 15 -

l200 to 1400 oc. The P ~n the resu1t~ng mater~a¡ ~s a1most com-

p1etely c+trate - and water-soluble (16)

After rev~ew~ng the pert~nent 11terature from Europe and

the Un1ted States on the ~~enan1a phosphates, 0011 (16) 1nd~-

cated that under a w~de range of so~l cond~t~ons they appear

to be nearly equa1 to superphosphate as a source of P for 1ong-

season crops when the mater~a1 1S f~nely ground, broadcast, and

thorough1y m~xed w1th the 5011 He further ~nd1cated that they

are not sU1tab1e as a P source when banded 1n the 5011 In

general, however, the rev~ew1ng author d1d ~nd1cate that the

Rhenan~a phosphates wou1d appear to be qu~te effect1ve on the

more ac~d s011s

Le6n (12) conducted a greenhouse exper1ment on a Car1magua

OX1sol, 1n Co10mb1a, w1th Sty10santhes guyanens~s (2 cutt~ngs)

and showed that Rhenan1a phosphate was super10r to TSP but ~n-

fer10r when magnes~um ox~de and calc~urn s11~cate were 1ncor-

]:lorated wüh the TSP (F1g 14) Th1S would 1nd1cate that there

was a magnes~urn def~c1ency 1n the s011 1n add1t10n to P

Fused Hagnes1urn Phosphates (FMP) These phosphate fert11-

1zers are made by fus1ng PR, serpent1ne or o11v1ne, and s111ca

at about 12S0°C Th1S phosphate, depend~ng upon the compos1-

t10n and rat10 of mater~als used w1ll usually conta1n about

29-33% CaO, 17-19% MgO, 19-21% P20 S ' 22-26% S102 , plus small

percentages of Fe and Al oX1des, all of Wh1Ch are a1most com-

pletely soluble ~n 2% c~tr~c aC1d (2)

Early ~nvest1gat10ns by Waltha11 and B~<G>~r;;'\T J \S~~}

BIBLIOTECA

- 16 -

pot exper~ment w~th two so~ls, pH 4 9 and 5 3,us~ng sudangrass

(2 cutt~ngB) as the teat crop,found that the FMP was equally

effect~ve as a P souree as both TSP and SSP

rate of P20 s for all P carrlers was 40 pp2m

The appl~catlon

In BraZl1, where a Japanese manufactured FMP ~s commonly

used for certa~n crops, research results have been most favor-

able Alvarez et al (1) conducted flve experlments wlth sugar-

cane on three d~fferent so~l types w~th varylng rates of phos­

phate ln the State of San Paulo They showed that thermophos­

phate was substant~ally better than any other P carrler used

The average of the f~ve exper~ments, wlth three rates of P20s

(50, 100 and 150 kg!ha) lncluded, gave percentage yleld ~ncreases

of 49 for the FMP and only 35 for SSP In another ser les of

experlments w~th corn ln the State of San Paulo, Mlranda et al

(41) showed slmllar results uSlng the F!W In three exper1ments

w1th P20 S rates of 60 and 120 kg!ha, these researchers found

that the thermophosphate fert111zer outperformed SSP,on a re la­

tlve scale,by 127 to 100

In Colombla, Le6n (12) conducted a greenhouse experlment

on an aC1d Carlmagua OXlso1 wlth Stylosanthes guyanensls, and

showed that the Japanese FMP was superl0r to TSP at all levels

of appllcat~on (F~g 14) When MgO and S102 were lncorporated

wlth the TSP, the FMP and TSP glve s~m1lar results In another

experlment on a Colomb1an Andept, Howeler (10) eoncluded that

FMP was not slgn~f1cantly d1fferent from TSP as a P souree on

Ylelds of beans

- 17 -

RESEARCH PROPOSAL

Ob}ect~ves of the Research Proposal

The ob)ect~ves are

1 - To evaluate the effect~veness of sources and methods

of appl~cat~on of phosphatefert~l~zers on so~ls of

trop~cal Lat~n Amer~ca

2 - To determ~ne the forros and ava~lab~l~ty of the reac­

t~on products of these fert~l~zers ~n so~ls as re la­

ted to the~r ~n~t~al and res~dual effect~veness

3 - To establ~sh cr~ter~a for applylng the results of the

f~rst two Ob)ectlves to d~fferent so~ls and crops at

var~ous locatlons by conduct~ng f~eld experlments on

selected so~ls throughout troplcal Lat~n Amer~ca

Currently ~t ~s planned that research wlll be conducted ~n

Colomb~a, Braz~l, Perú, Ecuador and other countrles as may be

approprlate

It lS hoped that these ob)ect~ves can be accompllshed through

lnterrelated and pert~nent laboratory, ~ncubatlon, greenhouse,

and f~eld exper~ments In the followlng d~scuss~on, the authors

wlll attempt to be SUCClnct but thorough ~n thelr reason~ng and

Justlflcat~on for the proposed research

Sltuat~on Stateroent

G1Ven the facts that the ac~d OXlsols, Ultlsols, and ln­

cept~sols ~n trop~cal Latln Amer~ca are not only low ln both

- 18 -

ava~lable and total P but also f~x large quant~t~es of P, ~t

becomes obvioqs that pfOrer so~l management of P fert~l~zers

~s extremely ~mportant It ~s al so apparent that the use of

trad~t~onal sources of phosphate fert~l~zers such as SSP or TSP

may not be acceptable sources for most crops because of the~r

relat~vely h~gh costs and because h~gh rates are necessary even

when they are banded (12) The d~reet appl~cat~on of ground

phosphate rock (PR) alone ~s probably not a su~table alternat~ve

e~ther due to ~ts ~n~t~al rate of release of F and cost of

transportat~on The authors real~ze that certa~n crops sueh

as cassava, and sorne legume and grass forages are capable of

forag~ng for P qu~te effect~vely, from even the med~um or low

react~v~ty roeks, but nevertheless th~s s~tuat~on ~s not true

for most erops It ~s al so understood that sorne of the PRs are

h~gh ~n react~v~ty but due to geograph~c d~str~but~on and ~n­

frastructural problems, the d~rect appl~cat~on of these rocks

~s probably l~m~ted to certa~n areas

Although the use of comb~nat~ons of broadcast PR w~th banded

TSP or SSP have shown promkse as overall sources of ~mmed~ately

alld reskdual forms of P, once aga~n the prev~ously d~scussed

restr~ct~ons st~ll apply Furthermore, a normal pract~ce of band­

~ng TSP ~s probably not feas~ble ~n e~ther apasture or forage

product~on scheme wh~ch ~s so ~mportant ~n trop~cal Lat~n Amer~ca

The use of other altered PR products, however, may have

sorne advantages over the prev~ously mentkoned P carr~ers In

the few tr~als wh~ch have been conducted, for example, w~th

part~ally ac~dulated FR alld FMP, the responses have been

- 19 -

generally egual to or SUperLOr to TSP (FLgs 12,13,14). There

would also ~ppear to ba sorne econom~c advantages ~n us~ng these

forms In add~t~on, ~t ~s feas~ble to granulate these products

thus overcom~ng the handl~ng problems normally assoc~ated w~th

PR The potent~al mer~ts of these altered products w~ll be d~s-

cussed ~n more deta~l later

Phosphate Hater~als to be tested

Currently there are three long-term f~eld exper~ments be~ng

condueted ~n Colomb~a on rates and sources of several PRs, TSP,

and baslc slag The resldual value of the phosphate carr~ers

are be~ng ascerta~ned w~th test crops of cassava, beans and

Bracn~arla decumbens These exper~ments, wh~ch were set up by

a prev~ous ~nvest~gator*, wlll be contlnued AIso, several

other PR exper~ments, wh~ch have been reported on, were conduc-

ted ~n Colomb~a, by IFDC In addltlon another experlment was

set up by Drs Sánchez and Le6n th~s past year ln WhlCh 3 PRs

(Pesca, HUlla and Gafsa) are belng compared w~th TSP at SlX

d~fferent rates of P Var~ous comblnatlons of the PRs and TSP

are also lneluded The test crops are Panlcum maXlmum and

Andropogon gayanus, each lnterseeded wlth Centrosema 1733

Forage product~on,and uptake and removal of P w~ll be determ~ned

ln th~s long-term resLdual study Based on the studLes that

have been and are currently belng conducted w~th PR and TSP,

Lt lS the oplnlon of the authors that emphasls should now be

dlrected towards the use of part~ally aCLdulated PR and

* L L Harnmond, S011 SClentlst, InternatLonal FertLllzer Deve10pment Center, ~!uscle Shoals

- 20 -

thermophosphates

parattve purposes

Phosphate rock and TSP w~ll be used for com-

Part~ally Ac~dulated Phosphate Rocks

S~nce the so~ls ~n the target area f~x large quant~t~es

of P (12, F~g 4), ~t would seeM reasonable that apply~ng a P

mater~a1 that conta~ns a large percentage of ~ts P ~n a relat~ve-

ly unf~xable form would have sorne advantages Once th~s par-

t~ally ac~dulated mater~al ~s appl~ed to the so~l the monocal­

c~um phosphate ~s converted to dLcalc~um phosphate and phosphor­

~c ac~d It ~s hoped that the PR and the ac~dulated mater~als

would rema~n ~n ~ntLmate enough contact ~n the so~l, so that

at least a port~on of the phosphor~c ac~d would then react w~th

the PR, thus mak~ng ~t ava~lable for plant uptake In add~t~on

the ac~d~c nature of the so~ls themselves should also help to

solubLl~ze the rema~n~ng PR S~nce the P ~s probably becom~ng

ava~lable over a per~od of t~me, thus prov~d~ng a cont~nuous

supply to the plants, perhaps the adverse common ~on effect of

the ~ron and alum~num can be somewhat overcome

HeLean and Wheeler (40) state that, "the smaller quant~ty

of soluble P ~n the part~ally ac~dulated mater~al compared to

the tr~p1e superphosphate (100% ac~dulated) n~ght then cause

less H3P04 to forro, and, ~f part of that formed were d~ss~pa­

ted on the rock phosphate, then less Al and Fe would be act~-

vated to revert the P to unava~lable forms" They furtner ~n-

d~cate that, "the soluble P ~n the part~ally ac~dulated mate­

r~al mLght st~mulate the plant ~n~t~a1ly, so that they can make

- 21 -

more eff~cient use of the unreacted rock phosphate when the

soluble P accessíble to the roots has been exhausted"

Another potent~al advantage to the part~ally ac~dulated PR

~s that of granulat~on Past attempts at granulat~ng PR have

not been successful because of decreas~ng the effect~ve surface

area of the PR ~n contact w~th the so~l It may now be poss~ble

through the "m~n~granulat~on" process*(Tyler-SO+200 mesh) w~th the

part~ally ac~dulated PR to have a P fert~l~zer that ~s both ef­

fect~ve as a P source and easy to handle from a phys~cal stand-

Tl1ere are also ~nd~cat~ons that surface appl~cat~ons of

soluble forms of phosphate may be effect~ve ~n st~mulat~ng veg-

etat~ve growth on ex~st~ng savannas (43) In sorne areas of

Braz~l aerLal applLcat~ons of SSP are faLrly commonplace ~n na-

t~ve forage product~on (Personnal communLcat~ons w~th Cl~n-

ton Shock, IRI BrazLl) The "mLn~granulated" part~ally ac~du-

lated PR mLght al so lend ~tself to th~s type of applLcat~on

The econOrnLCS of produc~ng the partLally ac~dulatea PR

should be qULte favorable because of the smaller amounts of the

sulfur~c or phosphor~c aCLds be~ng used ThLS LS espec~ally

true Ln trop~cal LatLn Amer~ca where the costs of these aCLds

are very hLgh

Greenhouse and fLeld experLments are beLng planned and

~n~t~ated Ln 1978 uSLng vary~ng levels of partLally aCLdulated

PR These mater~als w~ll be made uSLng sulfurLc aCLd and rocks

* clew granulat~on concept developed by the InternatLonal Fert~l~zer Development Center, 11uscle Shoals

- 22 -

of low, med~um, and high react~v~ty Whenever possible, local

sou~ces Qt PR w~¡l be used The exper~ments w~ll also include

rata studies, methods of appl~cat~on, and granu1ated versus un­

granulated mater~als Eff~c~ency of the test mater~als w~ll

be compared to TSP and ground PR Several d~fferent test crops

w~ll be stud~ed for uptake and rernoval of P The cropp~ng ph~­

losophy w~ll be d~scussed ~n more deta~1 later

Thermophosphates

The use of thermophosphates espec~ally fused magnes~um

phosphates (Fr~) al so appear to have good potent~al as a phos­

phate fert~l~zer ~n trop~ca1 Lat~n Amer~ca It has be en pre­

v~ously shown (1,38,41) that th~s mater~al ~s general1y supe­

r~or when compared w~th TSP (FlgS 14,15) The ~mpllcat~ons of

th~s are not clear, however, León ~n prellffilnary stud~es ~nd~­

cates that both sOll and plant calc~um and magnes~um contents

are somewhat hlgher when F~P lS used versus TSP In add~t~on

the P content alsoappears to be marg~nally hlgher There ~s

also the poss~b~l~ty that the ava~lable so~l sll~cates may be

~nvolved,elther d~rectly or ~nd~rectly,but the experlments were

not des~gned to sort thlS out Fox et al (26), for example,

~ncreased sugar ylelds by 12 ton / ha through the use of a cal­

c~um s~l~cate slag

There lS also a marked d~fference ~n solub~l~t~es of P ln

TSP and FMP The TSP ~s most1y all water-soluble whereas the

F!1P ~s c~trate-but not water-soluble A1though both forms of

Pare generally consldered ava~lable to p1ants,perhaps the P

- 23 -

Ln the FMP LS not as vulnerable to fLxatLon by Al and Fe Ln the

so~l.

At thLS pOLnt Ln tLme Lt ~s dLffLcult to know Lf the FMPs

would have an economLC advantage over other P sources such as

TSP or SSP because of the hLgh energy Lnputs ~n fusLng the ma­

terkals In future years, however, FMPs may becorne very com­

petLtLve econorn~cally when the hydroelectrLc potentLals of the

Latkn AmerLcan countrLes are realLzed SLnce large known re­

serves of PR (36, FLg 16) and serpentLne/ol~vLne (8,20,23,32) are

al so present L~ these countrLes, the essentLal raw materLal are

there for makLng FMP

It ~s LnterestLng to note that FMPs may becorne a manufac­

tured product Ln ColombLa Ln the near future In 1974 the Co­

lombLan government commLssLoned a Japanese Consult~ng fLrrn to

make a feasLb~lLty study on PR uses and specLfLcat~ons for a

FMP plant (31,32) The results of the study were quLte favor­

able for ~ts product~on

Greenhouse experLments wLll be des~gned to try and deter­

mLne why plants ~n general respond better to FMP than TSP

Treatments of FMP w~ll also be an kntegral part of the green­

house and fLeld stud~es proposed under the prevLous sectkon on

partLally aCLdulated PR

Other MaterLals

Although the partLally ac~dulated PRs and Fl1Ps have been

hLghlkghted Ln thL<' paper, other combknatLons of PR and sulfur,

and PR and sLlLca, for example, wkll be exper~mented wLth

- 24 -

~n greenhouse t~~als If any of these appear prom~s~ng f~e¡q

exper~ments at represeptat~ve s~tes w~ll also be conducted

Other Laboratory, Incubat~on, and Greenhouse Stud~es

Another aspect of the proposal ~s chem~cal and m~neralog~-

cal character~zat~on of the ac~d Ox~sols, Ult~sols,and Incept~-

sols ~n the target area It ~s extremely ~mportant to be able

to pred~ct the behav~our of d~fferent p carr~ers under the vary-

~Pg so~l cond~t~ons It was noted earl~er (12), for example,

that p f~xat~on capac~t~es of 350 to 750 ppm are qu~te common

~n these so~ls (F~g 4) These sorts of ranges would s~gn~f~-

cant1y alter both the P carr~er used and amounts of phosphate

to app1y In order to further quant~fy the spectrum of so~ls

~n trop~cal Lat~n Amer~ca, representat~ve so~ls w~ll be co11ec-

ted,for analys~s and study,from several areas ~n Colomb~a

Phosphorus fract~onat~on of these so~ls w~ll be ~ncluded

~n the ~n~t~al laboratory analyses Subsequently, the proposed

P carr~ers w~ll be ~ncubated w~th the so~ls and t~me stud~es ~ -

on ava~lable, f~xed,and lab~le forms of P w~ll be determ~ned

Greenhouse tr~als, w~th several crops w~ll also be conducted

~n conJunct~on w~th these stud~es to correlate plant P uptake

and rernoval values w~th the results obta~ned ~n the laboratory

and ~ncubat~on stud~es

These sorts of ~nvest~gat~ons w~ll be ~rnportant ~n g~v~ng

a better understand~ng and d~rect~on when establ~sh~ng other

greennouse and f~eld exper~roents ~n th~s overall proJect

- 25 -

croe~ing and Management Strategy

The Phosphorus Pro)ect has respons~b~l~ty for test~ng a

nurnber of potent~al P fert~l~zers on a var~ety of d~fferent

crops In general these crops w~ll ~nclude

r~ce, and both grass and legum~nous forages

cassava, beans,

other test crops

could ~nclude corn, soybeans, peanut, sesame, sugarcane,and

cowpeas Although th~s seems l~ke a confus~ng number of crops

~t must be remembered that exper~ments w~ll be conducted on

several d~fferent so~ls under varyLng cl~mes Furthermore, the

authors feel that uSLng test crops wh~eh are normally grown ~n

a g~ven area LS very ~mportant

Beeause of the Lmportance of the beef ~ndustry Ln trop~eal

Lat~n Amer~ea, a eonsLderable effort w~ll be devoted to ~mprov­

~ng forage product~on through P fertLl~zatLon Although P fer­

tLl~ty tr~als w~ll be conducted on d~rect pasture fert~l~zatLon

and forage productLon, the concept of a erop sequence appears

to have added merLt

SLnce the cost of P fertLlLzers ~s relatLvely h~gh, Lt LS

not reasonable Ln many ~nstanees for a farmer or raneher to

plow up eXLst~ng savanna, Lneorporate fert~lLzer and ~mmed~ate­

ly replant a forage In order for the farmer to real~ze an Lm­

med~ate monetary return from the fertLlLzer Lnvestment, ~t ~s

suggested that h~gh value arable erops be planted for one or

more seasons before gOLng ~nto forage produet~on Th~s al­

lows for defray~ng sorne of the Lmmed~ate ~nput costs and ~n­

ereas~ng forage product~on Ln the long run

- 26 -

From a research standpo~nt th~s cropp~ng scheme offers the

opportun~ty to ga~n results fram the ~mmed~ately ava~lable P

as well as res~dual effects of the P fert~l~zers It also lends

~tself to work~ng w~th a var~ety of crops to the extent that

the~r P requ~rements from the var~ous fert~l~zers can be ascer­

ta~ned

If the requ~rements of the d~fferent crops are known ~t

seems feas~ble that a ta~lored P fert~l~zer and management pro­

gram could be packaged to ~nclude the arable and forage crop

sequence scherne In order to make P fert~l~zer recommendat~ons

crop spec~f~c, the behav~our of the P carr~ers, the plant re­

qu~rements, and the so~l chem~cal character~st~cs must be well

understood

Length of ProJect

The very nature and scope of the proposed phosphorus fer­

t~l~ty research program d~ctates a m~n~mum per~od of 7 to 10

years to accompl~sh the obJect~ves of th~s IFDC proJect proposal

- 27 -

R E F E R E N C E S

1 Alvarez, R , J C Ometto, A C P Wutke, H V Arruda, and E S Fre~re 1965 Adubacao de Cana-de Acucar XI - Ex­per~enc~as coro d~versos fosfatos (1961 a 1963) Bragant~a Vol 24, N° 9 pp nos unk

2 Ando, J 1959 Stud~es on fusad cale~um magnes~um phos­phate fert~l~zer Reports of the Fac of Eng , Chuo Un~v , Bunkyoku, Tokyo, Japan 0-2, N° 8

3 Arm~nger, W H , and M Fr~ed 1958 Effect of part~cle s~ze on ava~lab~l~ty to plants of phosphorus ~n phosphate rock from var~ous sources J of Agr~e and Food Chero Vol 6, N° 7 539-543

4 Arndt, W , and G A Melntyre ual effeet of superphosphate ghum on a later~t~c red earth 785-795

1963 The ~n~t~a1 and res~d­and rock phosphate for sor­Aust J Agr~c Res 14

5 Bennett, O L , L E Ensm~nger, and R W Pearson 1957 The ava~lab~l~ty of phosphorus ~n var~ous sourees of rock phosphate as shown ~n greenhouse stud~es So~l Sc~ Soc Aro Proc 21 521-524

6 Brams, E 1973 Res~dual so~l phosphorus under sustalned cropp~ng ~n the hum~d trop~es So~l Sc~ Soc Aro Proe 37 579-583

7 Brov,n, BE, and K O Jacob 1945 Greenhouse pot-culture tests on rock phosphates as sources of phosphorus for plants The Aro Fert 102(1) 11-12 28 30

8 Cathcart, J B 1975 Phosphate fert~l~zer mater~als ~n Co­lomb~a - ~mports, uses,and domest~e suppl~es J Res U S Geo1 Survey Vol 3, N° 6.659-663

9 CIAT 1974 Annua1 Report p 145 Centro Internac~onal de Agr~cu1tura Trop~cal, Cal~, Colomb~a

10 CIAT 1975 Annua1 Report p C52-53 Centro Internae~ona1 de Agr~eultura Trop~eal, Cal~, Co1omb~a

11 CIAT 1976 Annual Report p A47-~0, B65-72, C26-30 Cen­tro Internac~onal de Agr~cultura Trop~ca1, Cal~, Co1omb~a

12 CIAT 1977 Annual Report Centro Internac10nal de Agr~­cultura Trop~cal, Cal~1 Colomb~a In press

13 Chu, C R I H W Uoschler, and G l'I ~homas 1962 Rock phosphate transformat~ons ~n ac~d so~ls So~l SC1 Sac Aro Prac 26 476-478

, !

14

- 28 -~

, , -'.f' .-¡ ...

Dave10u~s, J , Y M Cano' 1976 Avances de las ~nvest~ga­c~ones real~zadas a través del Conven~o Fosbayovar duran­te las campañas 1974-75 y 1975-76 Un~vers~dad Nac~onal Agrar~a Depto de Suelos y Fert~l~zantes La Mol~na, L~ma, Perú '

r •

15 Doll, E C ~1975 ut~l~zat~on of phosphate rock for d~rect appl~cat~on to so~1s Internat~ona1 Fert~l~zer Development Center 11anuscr~pt Unpubl~shed

16

J.7

, D011, E C '1976 Rhenan~a Phosphates - Summary of Agrono­~~c Research Internat~ona1 Fert~l~zer D~velopment Center Hanuscr~pt Unpubl~shed_

. Doll, E e ,and L L Hammond 1977 Ut~l~zat~on of phosphate rocks for d~rect appl~cat~on to so~ls Paper presented at FAO workshop en so~l mgmt and conservat~on, ~n L~ma, Perú '

, 18 Doll, E e , HF ~ller, and J F Freeman 1960 In~t~al

and res~dual effects of rock phosphate and superphosphate Agron J Vol 52 N° 4 247-250

19

20

21

22

23

24' y

25

26

'" Ell~s, R ,Jr , M A Quader, and E Truog phate ava~1ab~l~ty as ~nfluenced by so~l Soc Aro Proc 19 484-487 "

1955 Rock phos­pH So~l SCl.

Eml.gh/G D Aprl.l1972 Wor1d phosphate reserves - ,are there really enough? Reprl.nted from Eng and M~n~ng J Pp pos unk

Ensm~nger, LE, and R W Pearson 1957 Res~dual effects of var~ous phosphates as.measured by y~elds, P32 uptake, and extractable phosphorus So~l sc~ Soc Am Proc 21 80-[,4

Ensm~nger, LE, R W Pearson, and W H Arm~nger 1967 Effect~veness of rock phosphate as a source of phosphorus for-plants USDA 8202, ARS 41-125 .,

Fassbender, H W 1967 Los fosfatos naturales de Sechura, Perú' Turr~alba Vol 17, N° 2,:pp 159-164

~"'" , . .-. "'-;', ,., ~ ; ... ...

Fassbender, H W , L Muller, and F Balerdl. 1968 Estu­d~o del fósforo en suelos de Amérl.ca Central 11 Formas y re1acl.6n> con Ja plan!:a T1."!rr~alba ':''lOl ,18, ¡;,tO 4 333-347

.. ~ ~. ~!-

7" • '"' -" _ t _ 1 '"

Fassbender,<H W 1969 Phosphorus fl.xat~on ~n trop~cal so~ls Agr~ :D~gest 18 20-28 ~

.. ... ... • <" ff

, " Fox, R L , J A S~~lva, O G D Sherman, 1967 So~l sugarcane So~l Sc~ Soc

R' Younge, D'L Plucknett, and plant sl.l~con response

Aro Proc 31 77~-779

ánd by

----_ ..... _~_ ....

¡ ,

l'

, ¡

27

28

29

30

, " - :9 -• . , -' • .f

,,:y. ,. 1

Ga11aho, F 1969 AC1du1ac1ón de la roca fosfór1ca'en el suelo Valor fert11u:ante de las mezclas "Roca fosJór1ca - sulfato'de amom.o"" ~lIT Tecnología 61 34-36

Hammond, L'L 1977 Effect1veness of phosphate rocks 1n Colomb1an s011s as rneasured by crop response and s011 phosphorus levels Ph D TneSl.s.L1brary, N1chJ.gan State UnJ.versJ.ty, East LanS1ng, MJ.ch1gan

r

Howe1er, R H and C M Woodruff 1968 D1SS01utJ.on and avaJ.lab1líty to'plants of rock ph9sphates of l.gneous and sed1rnentary Orl.g1ns SOl.1 SCJ. SOC Aro Proc 32 79-82

<-lIT Tecnologl.a Report 1969 Vol de la roca fosfór1ca en el "suelo

60 35-45 ACl.du1acl.ón Bogotá, Co1ombl.a

31 Japa~ConsultJ.ng Inst1tute 1974 Report on the prefeasl.­bl.11.ty survey oí the development and utl.1l.zatl.on of phos­phate rock l.n C01omhl.a Hl.b1ya Park Bldg , Yarakl.-C~o Chl.yoda-Ku, Tokyo, Japan ,

32

33

34

35

36

37

38

-Japan Consultl.ng Instl.tute rnagneSl.Uffi phosphate plant Chl.yoda-Ku" Tokyo, Japan

1974 8pecl.fl.catJ.ons of fused H1bl.ya Park Bldg Yarakl.-Cho

Joos, L L ; and C A Black 1950 AvaJ.labl.11.ty of phosphate rock as affected by partl.c1e Sl.ze and contact wl.th bento­nl.te and s011 of dl.fferent pH va1ues SOl.l SCl. Soc Am Proc 15 69-75 ., Kamprath, E J 1977 '(Repr;nt) Phosphorus pp138-161 In P A Sánchez (Ed ) "A Revl.ew of 8011s Research l.n Tropl.ca1

,Latl.n Amen.ca" North Caroll.na Agr ·Exp Sta Tech Bul N° 219 501.1 SCJ. Dept N C S U Ralel.gh, N C , , iehr, J R I and G H reactl.Vlty sca1e for appllcatlon TVA Bul

McCle11an 1972 A revl.sed 1aboratory evaluatl.ng phosphate rocks for dlrect ,Y-43 T V A , Muscle Shoals, Alabama

, León, L A 1977 TropJ.cal Aroerlca Cal1, Colombla

Use of rock phosphates l.n aCld sOlls of Unpubll.shed Sernlnar Manuscrlpt CIAT"

!'" " ~ '" '" '" ," "" ~ , .

- t ,. - +" ~ J. ...,

León, -L A", A •• RlañoJ E - Owen, and M' Rodríguez 1976 Research done l.n Co1ombl.a on the use of dl.fferent sources of phosphorus fOL fert11lzers UnpublJ.shed Manuscrlpt CIAT I Call. / Colomhla .t ¡ ~

<1' .,.., '... J

( ....... -t- "''' UcConn~ck, "Á , y F Gall.anos 1968 Evaluacl.6n químJ.ca y bJ.o16glca de la roca fosf6rlca parcl.alrnente aCl.dulada ACJ.dulacl6n con aCJ.d9,su1fdrl.co lIT Tecnológía, 56,9-25

,

- 30 -

39. ~!cLean, E O , 1956. Factors affect~ng y~elds and uptake of phosphorus by dlfferent craps 11 Rack phosphate and su­pa~phosphate separate and ~n comb~nat~on, under extended cropping So~l Sci Vol 82 N° 3 181-192

40 McLean, E O , and R W Wheeler 1964 Part~al1y ac¡dulated rock phosphate as a source of phosphorus to plants 1 Growth c~amber studles SOll SCl Soc Aro Prac 29 545-550

41 Mlranda, L T , G P Vlegas, E S Fre~re, and T Igue 1970 Adubacao do M~lho XXVII - EnsalOS com dlversos fosfatos Bragant~a Vol 29, Nó 28'301-307

42 Murdock, J T , and W A Seay 1955 The avallablllty to greenhouse crops of rack phosphate, phosphorus and calclum ~n superphosphate - rack phosphate m¡xtures. SOll Sel Soc Am Proc 19 199-203

43 North Car~l~na State Un¡Verslty 1973, 1974, 1975 Agronom­lC - Econom~c Research on Troplcal So~ls Annual Reports SOll SClence Department, N C S V , Ralelgh, N e

44 Peaslee, DE, e A Anderson, G R Burns, and C A Black 1962 Estlmat~On of relatlve value of phosphate rock and superphosphate to plants on dlfferent so~ls SOll SCl soc Aro Proc 26 566-570

45 Sánchez, P A 1976 Propert~es and management of so~ls of the troplcs pp 96-103 (Edj P A Sanchez John Wlley & Sons, New York

46 Sánchez, P A , and G Vehara 1976 t1anagement cons¡deratlons for ac~d s011s w¡th h¡gh phosphorus f~xat¡on capac~ty Paper presented at symposlum, "The role of phosphorus ln agrlculture", Internat~onal Fertll¡zer Development Center, Huscla Shoals, Alabama In press

47 Sánchez, P A 1977 ManeJO de suelos troplcales en la Ama­zonla Sudamer~cana Soc~edad Colomblana de la C¡enc~a del Suelo - 11emor¡as del V Congreso Latlnoamerlcano de la ClenCla del Suelo y IV Coloqu¡o Naclonal sobre suelos Suelos Ecuator~ales Vol VIII, N° 1 1-11

48 Terman, G L , and S E Allen 1967 Response oI corn to phosphorus ln underacldulated phosphate rock and rock­superphosphate fert~l~eers Agrlc and Food Chem , Vol 15, N° 2 354-358

49

50

Terman, G L , E e t~ón of phosphate 28 104-107

Moreno, and G Osborn rock ¡n 5011 SOll SC1

1964 Soc

ACldula­Am Proc

Walthall, fu::aon oI Chem , 3S

J H , and G L rock phosphate 774-777

Brldger 1943 w~th ollvlne

Fertll¡zer by Ind and Eng

- 31 -

51 Zapata, A 196a Efectos comparat~vos de la roca fosf6r~ca y las escor¡as Thomas sobre la repres~6n de la marchitez sorpresiva, el desarrollo y producc~6n de la Palma afr~­Capa, en la zona del Meta Instktuto de Fomento Algodonero Unpub m~meo

Table 1 Character1st1cs of the rna1n s011s at QU111chao, Car1magua and Cerrado Center Stat10ns

org Exchangeable cat10ns Al Ava11 Ava1.1. Hor1Z0n Clay Sand pH C (rneg/l00g) satn p* H20

(cm) % % (H 2O) % Al Ca Mg K CEC % (ppm) (%,vOl)

CIAT - QU111chao Ult1so1 (Orthox1c palehumult, clayey, kao11n1t1c, 1sohypertherID1c).

0- 20 71 4 4 1 4 1 20- 35 77 5 4 O 2 3 35- 62 84 2 4 3 1 1 62- 91 88 1 4 4 O 4 91-150 90 1 4 4 O 3

CARlMAGUA OX1.s03 (Tropept1.c

0- 20 37 6 4 9 3 1 20- 51 39 5 5 O 1 5 51- 82 40 5 4 8 O 8 82-117 40 5 5 4 O 6

117-132 48 5 5 8 O 4 132-152 52 4 5 9 O 3

CERRADO CENTER OX1s01 (TYP1C

0- 10 45 36 4 9 1 8 10- 35 48 33 4 8 1 2 35- 70 47 35 4 9 O 9 70-150 47 35 5 O 0.7

150- 260 42 39 4 6 0.3

* Bray Ir extract10n method

Source CIAT, 1977 Annual Report

2 7 2 7 3 2 1 1 2 O

Haplustox,

2 8 2 O 1 9 1 1

Haplustox, \

1 9 2 O 1 6 1.5 O 7

65 49 36 4 2 64 1 8 16 31 04 13 3 2 83 1 1 13 24 02 09 3.6 88 O 9 16 15 02 06 1 4 77 O 9 9 22 01 04 2 3 85 1 2 14

f1ne-clayey, ffi1xed, 1.sohypertherm1.c)

2 2 10 3 4 82 O 9 9 1 1 10 2 3 85 O 4 7 1 1 10 2 2 84 O 9 5 1 1 10 1 6 69 O 4 5 2 2 30 O 8 O 4 6 2 2 30 O 7 O 4 7

f1.ne, kaol1.n1t1c, 1sohypertherm1.c - LVE) J

T O 4 10 2 4 79 tr 11 O 2 05 2 2 89 tr 11 O 2 03 1 8 88 tr 9 O 2 01 1 7 88 tr 9 O 2 02 O 9 76 tr 9

Table 2 Percentage Relat~ve Agronom~c Effectlveness of VarlOUS Phosphorus

carrlers as Compared to Bas~c Slag andjor Trlple Superphosphate

R A E (%)

PanlcUm So urce Maxlmum Cassava Beans 1 Beans 2

TSP 62 100 100 72 * BaSle Slag 100 100

Sechura 94 82 65

N Carollna 82 82 79 72

Gafsa 80 84 93 72

e Florlda 53 73 57 52

HUlla 41 70 65 42

Tennessee 35 66 40 40

Pesca 27 67 28 28

* Resldua1

Source Hammond, 1977

23°N-----,~--~~~~~~---------------------------------

QUJ.llchao

o "

" " "

oo __________________ ~

TROPICAL AHERICA

(mühon!Ha)

548 Forests ras~

302 Savannas [i]illJ

850 Total 23°S

F~gure 1 Geograph~cal dJ.strJ.but~on of Ox~sols and Ult~sols

J.n tropJ.cal LatJ.n AmerJ.ca

Source CIAT, 1977 Annual Report

I

110

100 ------- ----------------

80

ro IJ ~

;!! 60 >-<lJ > .¡:; <tl ~

(!) 40 C a:

'* h

e e

20 k

o L.-Jc...J..._

Fl.gure 2

-p -S -B -Ca -N -K -Cu Mlsslng Nutl"'lent

Response of Centrosema pluml.erl. to

elements l.n the QUl.ll.chao Ultl.sol

ductl.on, fl.rst cut Mean of four

source CIAT, 1977 Annual Report

-Me -Zn -Mg

ml.ssl.ng nutrl.ent

Dry matter pro-

repll.catl.ons

F~gure 3 Est~roat~on of the cr~t~cal phosphorus

levels ~n the Qu~1~chao Ult~so1 under

greenhouse cond~t~ons Sum of two cut s

and mean of four rep1~cat~ons

Source CIAT, 1977 Annual Report

1200

t:; BRASILIA

1000 o QUILICHAO '" CARIMAGUA O PALMIRA

~

S 800 o. -

p. ~

O w i:'i ¡:.,

600 I P< ,

I I '" 1/

400 '" ",/i I I I

200 I I I

¡~ O '

,001 01 05 1 2 1 O

P IN SOLUTION (ppm)

Fl.gure 4 Phosphorus f1xatl.On l.sotherms of CPAC (Brasl.ll.a),

CIAT-Qul.ll.chao, CNIA-Carl.magua and CIAT-Palml.ra Source CIAT, 1977 Annual Report

1-o a. "-

20

15

(,!) 10

o ....J W

>-5

•

400 p: 955

200 r= 931

100

o~r:: 879 o

A :> 50

O ~::~~=:~.: ... )J~, ==:::=="~:r:6:~6:"~--=~-,1=======~1 =='-'~~===I ===~~6~1 r= 679

O 2 3 4 5 6 7

FJ.gure 5

CITRAT E SOLUBLE p2 0S' % Roe K

RelatJ.onshJ.p between yJ.eld of three cuttJ.ngs of gUJ.nea grasa grown on a carJ.magua OXJ.sol, and cJ.trate-soluble phosphorus J.n phosphate rocks

Source Hammond, 1977

4

'" .G "-r o .., ~

<. 3

H o U

... O

'el 2 ..... Q) ... >.

1

4 ~

'" < ~ o ..,

3 ~

.::

" o tl

\¡.¡

o 'el

2 H Q) ... >.

1

1. ChecJ 2 ¡DO 'f'? 3 200 TSl? 4 400 r ,1' 5 200 1 Ll 11 (1ur PR 6 200 um hJJUr. 1" + 200 rsp 7 700 rLOhrDi\. Pl{,

8 200 110 lD l rn + 200 TI:>¡> 9 100 llASl(' SLII(

r-r

r r-

r- I 1 4 3456189

1969 A 11-253

r "

r- f-1-

f-r

U lZ345GI39

1969 11 1l-2SJ

r

r-

r

123456739

1970 A H-253

r ~ r

r r-

I

1?3456789 1910 11 11-2 07

lile!! TLhPACE

-

.-~

1-.-

r-I

1234:'6739

1971 A H-207

/-1EDIU"j TJ:RR,'\Cr;

r

-.- 1-'-~

r 1 2 3 4 5 G 7 3 9

1971 1\ u-:>07

Pl,gure 6 r:ffect of broddca ,L appl:I.Catlon of d~ffcrent

forn'" ilnd r,t..cs of pÍ1o.sphoru, Lo COrn tJrown

on Lhc Jll.gh I.nd IllLuium tr 11.d<..C'" oí tho Last­

c)"n PJUl.l1S OC ColombJ(i (T .... l IlJ"crtad IXpCrl.­

mcni.. Stat:Lcn) Scurce León C!t al • 1976

s s P Araxá PR

1 O May 74 1 O May 74

O 8 O 8 L~me

ILSD 05

o O 06 06 " 3

04 A 45 04

02 02

O O O O ~ 86 345 1380 86 345 1380 /Il .c:

" ¡:; 10 o 10 Decerober 74 Decerober 74 .jJ

.jJ 8 8 ::;! o 6 6 H (l) 4- 4 1 LSD 05 o. I LSD 05 H 2 2 (l) .... .... O O n:! S 86 345 1380 86 345 1380 :>.. H n 12 12

t1arch 75 March 75

10 10

8 8

6 6

4- 1 LSD 05 4

2 2

O O 86 345 1380 86 345 1380

k9 P20S/ha

Phosphorus Appl~cat~on ~n February 74

F~gure 7 Ava~lab~l~ty of Araxá PR w~th t~me us~ng Brach~ar~a decumbens, grown on an Ox~sol ~n the Cerrado of Braz~l Source North Carol~na State Un~vers~ty,

1975 Annual Report

fJl <l)

.-¡ o tIl

¡:; I-l ::1 +' <l) ~

.-¡ I!) ¡:; ,..¡ tn ,.. I!) -"'"'

40

30

fI SSP - S1mple Superphosphate

20 • FB - FosBayovar PR

O HF - Reno H1perphosphate PR

10

0'--__

200 300 kg P20S/ha

F1gure 8 Comparlson of marg1nal monetary

returns w1th s1mple superphosphate

and two phosphate rocks w1th pota toes

1n the h1ghlands of Pera

Source Davelou1s et al I 1976

f\l

~ ~ o .., .....,

'O rl ()) rl

>< ¡;; n1 ())

pe¡

sol ~n c~t % of total P

.~: 100

2 5 18 6 18 O

~~~o 16 2 2 O

./~~ A 9 O / A • 9 5

1 5 :/0/ ·Xf::,. ____ • A •

1 O e= TSP o=. Gafsa PR Á= Sechura PR 0= Hu~la PR • = Pesca PR

O 5 {;= Tennessee PR

Q

O 50 100 200 400

F~gure 9 Response of Huasan6 beans to forms and rates of phosphorus on an Andosol from Popayán, Colomb~a Source CIAT, 1976 Annual Report

---~.~------------------------------

[ % p* RAE

20 Sechura PR 5 6 94 I

N Caroltna PR 6 7 82

.;"

/Rl _-7..c....-----C Bastc Slag 4 8 100 " ,/

15 ./

/' /

I ,..... O Trtple <J 20 3 62 O I Su¡:;erphosphate a. I

" Ol I '-' ¡ tolO <!) I _---íI HUlla PR 3 4 41 '"' ~ I nl --¿ I

(-Pesca PR 1 9 27 O

5

o 50 400

Phosphorus Apphed (ppm P)

Fl.gure 10 Effect of sources of phosphorus on Panl.cum maXl.mum dry matter proauctl.on (sum of 3 cuts) grown on a Carl.magua OXl.sol Wl.thout ll.ml.ng, l.n the green­house % P ; Cl.trate-soluble P of entl.re materl.al RAE = relatl.ve agronoml.c effectl.veness Saurce CIAT, 1977 Annual Report

•

• lit 11 -\ Iln

GAFSA pR , s

-' !

o !)1} 100 400

CEUTRAL FLORIDA PR

• • • J,d

4th

2 ••

.. 1st

O .0 -IM~~ '00

T1UPLF SL'PEIWtlOsPllA'IE • 5

4

.. ---'>

3

:v·----O 60 lOO .00

r

• 1'1 .... 'Aln.

Tl:.Nl\hS$EE PR

3n1 2nd

___ ";;::::=:..:,,,,-d:--'> 4th

'1 • ht

lVV:::>-: ~:..-- _

O!-~.O~I~.~a----------------~4~OO

SECfftlnA PE

• •

3,d

..., 4th

2nd

IGt

O SO '00 '00

I TSP .. AN1\1JAL

• •

.--<>

O .0 100 ... kg P20S /ha

F2gure 11 Dry matter y2eld of four cutt2ngs of Brach2ar2a decumbens, grown on a Car2-magua OX2so1, as affected by rate and source of phosphorus Source CIAT, 1977 Annual Report

I 2.5 I

2.0

o ~ e

1.5 O -u -¡¡

>-e

l. O o

'" IX)

0.5 .

FLgure 12

•

O 0- /

O/H/:/<~ ;/O~

o ~. •

X .~ 0-----e Bas~c slag

)C TSP

o 20% ac~d PR

• Hu~la PR

Response of beans to forros and rates of P

grown, on an Andosol near Popayán

Source CIAT, 1975 A~nual Report

o

~ " -

-o ., >. ~ .,

...a " -~ " ~ v>

" u

25 O ~*

*¿*~o -1'1

O~:~ 20 o

*1 /. ;: • -:;::::::; o

:~O 15

O e _______ * o

/ .--* e-* 10

o ~ TSP-bonded O"" Hu'!a * .. bcslc slog-broodcost "", Hu'¡o *,. bcslc slog-bonded [J '" Hu do

5 - " .. 5SP-bonded

OL---'-_-'-__ --'-______ ....I

O 50 100 200 400 O 50 100 200

F~gure 13 Response of Cassava to forros and rates of P

on an Ox~sol frorn Car~rnagua

Source CIAT, 1976 Annual Report

PR -broadcas t PR 20% oe,d PR +5(5 1)

400

! " :2 ~ • ~ ., o 8 r: '"

20

TSP .. Ttlplo suporphosphote TSP+MgO+ SI()Z

TSP+MgO +CnCOZ

_--..... 1SP

33 5 67 134 mg PzOs,l\>Ot

F\!P = Fused Magncsium Phosphate RP = Rhenania phosphate e = Coarse

201

FMPC

BS+MgO

ES

33 S 67

lIPR '" Hulla Phosphate Rack TPH ... Toormo Phosph"tte - Hutla TPP =< Therrno Phosphate-Pesea

201

20 F = Fine 20

10

__ -"'l,rMPF

RPF

UPC 10

F~gure 14 Dry matter y~eld oí two cutt~ngs oí Stylosanthes 9~anens~s 136, ~n a greenhouse exper~ment on a Car~magua Ox~solT as affected by rate oí phos­phorus w~th MgO, CaCOJ and S~02 and by d~fferent

thermophosphates Source CIAT, 1977 Annual Report

-o ..c

"" c: o --c: o +-

10 ORDINARY

8 SUPERPHOSPHATE

6 -------4

2

g O 86 345 "O

~ 10 TERMOFOSFATO

... <1> +--

8

Lime Rate _03 -----' -- O -- 45

1380

.Aa ~ -- - 45 o

:! ~ _------ 3 :/,::r-;:::' :::-:. ::. -----

6

>. 4 ... O d'

211l

o 86 345 1380

10 lime HIPERFOSFATO Rate.

8 3 4.5

6 -----~ O ---- ".. -- ----..... 4 ...-

2

o 86 345

10 ARAXA/

8

6

4

2

o 86 345

....-----1380

1380

F~g 15 Growth of Brach~ar~a decumbens (second cut) as affected by phosphorus sources, rates and l~mlng, ln the Cerrado of Brazll

So urce North Carol~na State Unlverslty, 1G74 Annual Report

BRASIL

Sarra de Pirocaua ~(:"""fr~."'. I1ha Trauira

Catalao •• PatQs de

Ml.nas e Araxá • Tapira

•

rl.gure 16 Rock phosphate deposl.ts in tropl.ca1

South Amerl.ca, Source Le6n, 1977