Urea-N management in relation to crop residue recycling in rice-wheat cropping system in north-western India

810re50urce 7echn0109y 61 (1997) 105-109 • 1997 E~e~er 50ence L1m1ted A11 f19ht5 re5erved. Pr1nted 1n 6reat 8f1tMn 0960-8524/97 $12{~ EL5EV1ER

P11:50960-8524

(97)00058-8

U R E A - N M A N A 6 E M E N 7 1N R E L A 7 1 0 N 7 0 C R 0 P RE51DUE R E C Y C L 1 N 6 1N R1CE-WHEA7 C R 0 P P 1 N 6 5 Y 5 7 E M 1N N 0 R 7 H - W E 5 7 E R N 1ND1A R. L. Yadav Pr0jea D1rect0raWf0r Cr0pp1n9 5y5tem5 Re5earch, M0d1pum~ Meemt-2~11~ ~ d ~ (Rece~ed 12 Decem6er 1996; rev15edver~0n rece~ed 24 March 1997; accepted 1 Apr11 1907) a pr0duct10n 0f 80 and 65 m~110n t0nne5 0f 9ra1n5, re5pect1ve~. At th15 1eve1 0f pr0duct10n, the am0unt 0f re51due5 ava11a61e fr0m the cr0p5 15 a60ut 218 m11110n t0nne9 7he 119n0ce11u10~c nature 0f the re~due5 make them 5uper10r t0 0ther 0r9an1c mater1~5 f0r 5u~a1n1n9 5011 0r9an~ matteL and enr1ch1n9 5011w~h m~r061a1 610ma55 r1ch 1n C, N, P and 5 dur1n9 the pr0ce55 0f dec0mp051t10n. H0weve~ due t0 50d0-ec0n0m~ c0mpu1510n5, m05t re51due5 are u5ed a5 an1ma1 feed 0r d0me5t~ fue1 1n rura1 area5. 5 1 m ~ a ~ 1n the n0~h-we~ern pa~ 0f the c0untry where a r1ce-wheat r0tat10n 15 f0110wed and harve5t1n9 ~ mechan~ed, cr0p re51due5 are 6urnt 1n 51tu, thu5 de~r0y1n9 a u5efu1 0r9an~-wa5te mater1a1. 0 n the 0ther hand, farmer5 he5~ate t0 re-cyc1e the5e re51due5 f0r ma1nta1n1n9 5011 fe~1f1ty 6ecau5e 0f the1r 510w dec0mp0~t10n due t0 a h19h C/N rat10 ( > 100). When 5uch h19h C/N-rat10 0r9an1c matef1~5 are added t0 the 5011 they 1mm06~12e nat1ve 50~-N dur1n9 dec0mp051t10n re5u~1n9 1n N def1dency 1n the f0110w1n9 cr0p 1n the ea~y pha5e 0f 9r0wth. N 5upp1ementat10n thr0u9h fert11~er5 at the t1me 0f re~due 1nc0rp0rat10n, h0weveL m19ht na~ r0w the C/N rat10, and acce1erate the dec0mp051t10n pr0ce55 and fav0ur m1ner~at10n 0f N. 7heref0re, there 15 a need t0 1n1t1ate 5tud1e5 t0 re5chedu1e f e ~ e r app1~at10n pract1ce5 f0r 5uch ~tuaf10n5. 1n the pre5ent c0mmun~at10n the re5u1t5 0f 0ne 5uch f1e1d exper1ment c0nducted at R.5. Pura and Kanpur under the ae915 0f the Pr0je~ D1rect0rate f0r Cr0pp1n9 5y5tem5 Re5earch have 6een ana1y5ed, and the effect5 0f c0nt1nu0u5 re~due 1nc0rp0rat10n, w1th N 5upp1ementat10n, 0n 5011 0r9an1c car60n and y1e1d trend5 have 6een eva1uated.

A f1eM expe~m~t wa5 c0nduc~d 0ver 5~ yea~ 6e~n 1990-1991 and 1995-1996 at R.~ Pum (32.5°~ 74.8°E, 308m a60ve mean 5ea ~ve~ and Kanpur ~ 2 ~ 8~34°E, 180m a60ve mean 5ea ~ve0 ~ w0~ 0ut ~112er N app11cat10n pmc~c~ w h ~ cr0p ~5Mu~ were ~ c ~ d ~ a ~c~wheat cr0pp1n9 ~5t~m. Fr0m ~e rec0mm~ded 1e~e~ ~ N ~ 100k9/ha at R.~ Pum and 120k9/ha at Kanp~ ~ r ~c~ and 120 k9/ha at 60~ ~e ~ t 1 0 m ~ r whea0, w h ~ 20 k9 ~ the ~tr09en ~,a5 app~d at the t1me ~ re5Mue ~c0~0m~0n and ~e rema~der du~n9 ~ e cr0p ~ 0 w ~ pe~0~ f1e1d5 ~ ~e cr0p5 we~ 519n~c a n ~ ~wer ~an ~ e 06m~ed under 0 ~ N 5chedu11n9 pmc~c~ t~ed ~ ~ e expe~me~ H 0 w e ~ when an extra 20 k9/ha n1tr09en wa5 app11ed at ~e ~me ~ re5Mue ~c0~0m~0n 0ver and a60ve ~ e ~mm~d N d05e5 at ~ ~ Pura, and N ~ve~ we~ enhanced ~ 20 k9/ha 0ver ~e rec0mmended m~5 at Kanpu~ ~ e cr0p5 y~M wa5 ~e h19h~ 0n ~e a~ra9e ~ 5~ cr0p ~ c ~ ~ e p m ~ 5 p ~ d u ~ d an add# ~0na1 150 and 510 ~ ~a~5/ha at R.~ Pura, and 5 ~ and 810 k9 ~ a ~ 5 ~ a at Kanpur ~ ~ce and wheat cr0p5, re5pect1ve1y. Eve~ mpee ~ 5 t e d ~ ~ e p u ~ h a ~ ~ add1t10na1 ~tr09en f0r app11cat10n • the ~ c ~ w h ~ t ~5~m ~u5 e a m ~ mpe~ •58 at R.~ Pum and mpe~ 1 2 ~ at Kanpu~ 7he ~m~trend ~uat10~ ~d1ca~d a 9radua1 ~ c ~ a ~ • ~e p~duct1v~ ~ ~ c ~ h ~ t ~5tem at Kanpu~ w h ~ at ~ Pum y1e1d5 5ta~ed m ~c11ne after ~e ~1rd ~ 0f ~ e e x p e ~ m ~ 7h~e tren~ we~ a ~ 0 c ~ d ~ ~e 0~an1c-C c0n~nt 0f ~e 5 ~ • 1997 E ~ e ~ 5 ~ L~ Key w0rd5: Cmp ~Ndue~ N - ~ N ~ C r1ce-wheat r0tat10n.

0r9an1c-C

1N7R0DUC710N ME7H0D5

7he 4uant1ty 0f re51due5 1eft 6y r1ce and wheat cr0p5 a~er harve5t ~ e4ua1 t0 150% 0f the we19ht 0f the1r 9ra1n y1e1d5 (8haradw~, 1995). 1n 1nd1~ r1ce and wheat are 9r0wn 1n 42 and 24 m11110n hectare5 w1th

5Re c h a r a ~ e ~ 2 ~ n A f1e1d exper1mem wa5 c0nducted 0ver 5~ year5 fr0m 1990-1991 t0 1995-1996 at R.5. Pura 0ammu

105

106

R. L. Yadav

and Ka5hm1r) and Kanpur (Utmr Prade5h) under the Netw0rk Re5earch P~09ramme cf Cr0pp1n9 5y5tem5 Re5earch. R.5. Pura 15 ~ c ~ e d at 3~5°N 1 ~ u d e , 74.8°E 10n91tude and 308 m a60ve mean 5ea 1eve1 1n a 5u6-hum~ a9r0-ec~0~c~ 20ne ha~n9 m1~ 5ummer5 and c01d w1nter~ w~1e Kanpur 15 ~ c ~ e d at 25.26°N 1 ~ u d e , 8~34°E ~n91tude and 180 m a60ve mean 5ea 1eve1 ~ a 5em~ar~ a9r0e c ~ 0 ~ c ~ 20ne w1th hct dry 5umme~ and m0der~e w~. 7he 50115 0f the expef1menm1 f1te at R.5. Pura are Eutr0chrept5 ~w1and daye~ wh11e th05e at Kanpur are a11uv~m Ur1c u ~ 0 c h ~ p ~ w1th pH 7.35 and 8.~ re5pe~Ne1y. 7he 1n1t1a1 c0nten~ 0f 0r9an1c car60n, and ava11a61e P and K were 0.43%, 10.4 and 91.5 k ~ ha at R.5. Pura, and 0.10%, 18.4 and 218 k~ha at Kanpu~ re5pe~Ne~. 7reatment and cr0p cu1ture 5even Weatment5 0f urea-N 5chedu11n9 were te~ed. 7he5e were: 7~=N appf1ed a5 per rec0mmended 1eve1 and t1me, t0 60th the cr0p~ n~r09en wa5 n0t appf1ed at the t1me 0f re~due 1nc0rp0rat10n. 72=re c0mmended N 1eve1 t0 cr0p~ 0f wh~h 10 k9 wa5 app1~d at the t1me 0f re51due 1nc0rp0rat10n. 73=re c0mmended N 1eve1 t0 cr0p~ 0f wh~h 20 k9 wa5 app11ed at the t1me 0f ref1due 1nc0rp0rat10n. 74=Cr0p5 fe~11~ed w1th rec0mmended 1eveh 0f N p1u5 an add1t10n~ 10 k9 N/ha appf1ed at the t1me 0f re51due 1nc0rp0rat10n, 75=cr0p5 fe~11~ed w1th rec0mmended 1eve15 0f N p1u5 an add~10n~ 20 k9 N/ha appf1ed at the t1me 0f re51due 1nc0rp0rat10n. 76=rec0mmended N 1eve1 enhanced 6y 10 k9 N/ha; N wa5 n0t app11ed at the t1me 0f re51due 1nc0rp0rat10n. 77=rec0mmended N 1eve1 enhanced 6y 20 k9 N/ha; N wa5 n0t app11ed at the t1me 0f re51due 1nc0rp0rat10n. 7he ~eatment5 we~e rep1~ated f0ur t1me5 1n a Rand0m12ed 81ack Def19n. 7he p10t 5~e wa5 6 × 5 m. Each p10t 0f the tr1~ receNed the 5ame fe~11~er ~eatment thr0u9h0ut the exper1ment and an annu~ r1ce-wheat d0u6~-cr0p 5y5tem wa5 1mp05ed dur1n9 the 5~ year per10d fr0m 1990-1991 t0 1995-1996. 7he rec0mmended 1eve1 0f N f0r r1ce wa5 100 k9/ ha at R.5. Pura and 120 k9/ha at Kanpu~ F0r wheat, the rec0mmended 1eve1 0f N at 60th the 10cat10n5 wa5 120 k9/ha. A5 ~andard rec0mmendat10n~ N wa5 app1~d 1n three e4ua1 5p11t5 1n wheat; at 50w1n~ at cr0wn r00t 1n1t1at10n ~a9e (21 day5 after 50w1n9), and at max1mum t111er1n9 5ta9e (55 day5 after 50w1n9). 1n r1ce ~50, N wa5 app11ed 1n three e4u~ 5pf1~; at ~an5p1ant1n~ at max1mum t1~ef1n9 and at pan1c1e 1n1t1at10n 5ta9e. 7he cr0p5 ~50 receNed a un1f0rm app1~at10n 0f 60 k9 each 0f P205 and K20/ha a5 6a5a1 d05e. N1~09en, ph05ph0ru5 and p0ta5f1um were appf1ed thr0u9h urea (46A% N), ~n~e 5upe~ ph05phate (16% P~05) and mur1ate 0f p0ta5h (62% K20), re5pectNe~. Each yea~ r1ce (cv PC-19 at R.5. Pura and 5a~ j00-52 at Kanpu~ wa5 tran5p1anted 1n Ju~ uNn9 tw0

5eedf1n9~h111 at 20 x 10 cm 5padn9 and harve5ted 1n the t1nt week 0f 0 ~ 0 6 e ~ Wheat (cv HD 2329 at 60th the 10cat10n~ wa5 50wn 1n the 5ec0nd week 0f N0vem6er u~n9 100 k9 5eed/ha 1n r0w5 23 cm apa~ and harve5ted 1n Apr11. Harve5t1n9 0f the cr0p5 wa5 d0ne m a n u ~ 6y 5~k1e d05e t0 the 9r0und 1eve1 and the wh01e a60ve9r0und 610ma55 rem0ved fr0m the p10t 0f each ~eatment. 7he p10~ were kr19ated 500n after rem0v~ ~f the harve5ted 610ma55. 7hre5h1n9 (t0 5eparate 9r~n and 5~aw) 0f the cr0p5 wa5 d0ne p10t-w15e 0n the thre5h1n9 f100r 0f the re5earch farm 6y an e~ctr1c-dr1ven thre5he~ 7he ch0pped ~raw; 1-3 cm ~2e 610wn 0ut 0f the thre5her wa5 c0Hected 0n the p01ythene 5heet f0r each p10t and the entke 4uant1ty (after we~h1n9) 5pread 1n 1he re5pe~Ne p10~ when 5011 m01~ure made the 9r0und w0rka61e. U r e ~ N wa5 6r0adca5t 0n the p10t5 wherever re4uffed a5 the ~eatment 0n the 5ame day. 5~aw wa5 m~ed 1n the 5011 6y 5pade and p10t5 1eft und1~ tur6ed unt11 a pre~0wn 1rr19at10n wa5 9Nen 10 day5 pr10r t0 wheat 50w1n~ and pudd11n9 d0ne f0r r1ce tran5p1ant1n9. 7here wa5 an appr0~mate~ 30-day per10d 6etween r~e ~raw 1nc0rp0rat10n and wheat 50w1n~ and a 65-day per10d 6etween wheat ~raw ~c0rp0rat10n and r1ce tran5p1ant1n9. 7he ~ce wa5 kr19ated 6y f100d1n9 the p ~ u w11h 2.5 cm deep ~and1n9 water at each kr19at10n. 7he next ~69at10n 1n r1ce wa5 9Nen when the 5011 m0~ture reached 5aturat~n 1eve1. 7he cr0p c0nt1nued t0 6e kr19ated 11ke th15 unt11 1t att~ned the harden1n9 0f the 9ra~ 1n the pan1c1e ~a9e. Wheat wa5 1rr19ated f1ve t1me5, at cr0wn-r00t 1n1t1at10n (21 day5 after 50w1n~ DA5), max1mum t1Her1n9 (55 DA5), j01nt1n9 (75 DA5), ear emer9ence (100 DA5) and m11k1n9 (135 DA5) ~a9e5. 065ervat10n5 After the harve5t 0f wheat 1n Apr11 each yeaL 5011 5amp1e5 were c0Hected f 0 m 0 t0 20 cm depth 1n each p10t and ana~5ed f0r 0r9an~ car60n, amm0n1um acetate extracta61e-K, and 6~ar60nate extracta61e-P (Jack50n, 1973). H0weve~ 1n th~ c0mmun~at10n 0n~ the data rec0rded after the t1nt and 5~th cyde5 0f the cr0pp1n9 5y~em are rep0~ed. 7he 9r~n f1e1d data 0f r1ce and wheat under a11 the 5even ~eatment5 were 5u6jected t0 t1me trend an~y5~ u51n9 the f0110w1n9 e4uat10n:

Y=a + ~ + ~ 2 where, Y 15 e5t1mated 9ra1n y1e1d (~ha), t 15 t1me 1n year5, 6 and c are c0n5tant~ and a ~ the 1ntercept 0f the f1tted trend curve. RE5UL75 AND D15CU5510N

7he r1ce and wheat cr0p5 0f the r~e-wheat cr0p 5e4uence when 9r0wn w1th recyded re~due5 0f the preced~9 cr0p 9ave 10we5t y~1d5 when 20 k9 nRr0-

N-mana9ement and r1ce-wheat cr0pp1n9 9en 0ut 0f the rec0mmended N 1eve~ wa5 appf1ed at the t1me 0f ref1due 1nc0rp0rat10n and the remNnder appf1ed 1ater 0n dur1n9 the cr0p 9r0wth cyde a5 per rec0mmendat10n5 (7reatment 73). 7 h ~ wa5 pr06a6~ 6ecau5e the nRr09en re4u1rement5 0f the cr0p5 may have n0t 6een fu1~ met 5u65e4uenf1y a5 the 20 k9 N wa5 u5ed 1n1t1N~ t0 acce1erate the dec0mp05R10n 0f the 1nc0rp0rated re51due5 (8handaf1 et aL, 1992). H0wever, when an ex~a app1~at10n 0f 20 k9 N 0ver and a60ve the rec0mmended N 1eve1 wa5 made at the t1me 0f re51due 1nc0rp0rat10n and 5u65e4uent N dre5~n95 were made a5 per rec0mmended pract~e (7reatment 75), the cr0p5 y~1d5 were the h ~ h e ~ at R.5. Pura, a5 5een 1n the mean f1e1d data 0f the 5k cr0p cyde5 pre5ented 1n 7a61e 1. At Kanpu~ h19he~ y1e1d5 were rec0rded when rec0mmended N d05e5 were enhanced 6y 20 k9/ha (77). 7he 6enef1d~ effect5 0f the extra N d05e5 at 60th the 10cat10n5 were pr06a6~ due t0 an acce1erated dec0mp051t10n pr0ce55 0f the recyded re51due5 a5 a re5u1t 0f the pr1m1n9 act10n 0f added fe~H~er N (Hauck and 8 r e m n e ~ 1976; Jenk1n50n et a1., 1985) 1n exce55 0f the rec0mmended N 1eve1 under a fav0ura61e C/N rat10. Ak1nyem1 and Adew ~ e (1984) a150 f0und rap1d dec0mp0f1t10n 0f recyded 0r9an1c matef1~5 w1th add~10n 0f nRr09en at the t1me 0f ref1due 1nc0rp0rat10n. At R.5. Pura, 6ecau5e 0f the m11d temperate d1mat~ c0nd1t10n~ 5011 m1cr061~ act1v1t1e5 are 510w, theref0re dec0mp051t10n 0f 1nc0rp0rated re51due5 15 a150 510w. App11cat10n 0f N at the t1me 0f re51due 1nc0rp0rat10n under 5uch a 5Ruat10n m ~ h t acce1erate the dec0mp0f1t10n pr0ce55 and prevent 1mm0611~at10n 0f nat~e 5011-N (8haradw~, 1995). 0 n the 0ther hand, 1n the re1atNe~ warmer d1mate

107

at Kanpu~ 5011 m~r061N act1v1t~5 m19ht Nready 6e 50 h19h a5 t0 1nR1ate the pr0ce55 0f dec0mp051t10n. 7heref0re, nRr09en may n0t 6e re4u1red at the t1me 0f re51due 1nc0rp0rat10n. H0wevea 0nce the pr0ce55 0f dec0mp0~t10n 6e91n~ the app11ed n1tr09en may 6e u t ~ e d eff1denf1y 6y the 9r0w1n9 p1ant5 due t0 the fav0ura61e effect 0f 9reater 0r9an1c matter 1n the 5011 (Yadav and Pra5ad, 1992). 7he mean y1e1d data 0f 5N cr0p cyde5 revea1ed that app1~at10n 0f 20 k9 extra N/ha 0ver the rec0mmended-pract~e N 1n 75 at R.5. Pura and 77 at Kanpur pr0duced 150 and 510 k9/ha add1t10nN y1e1d5 0f r1ce and wheat, re5pectNe~, at the f0rmer 10cat10n, and 570 and 810 k9/ha at the 1atter 10cat10n. Every rupee 1nve5ted 1n the purcha5e 0f add1t10nN N f0r app1~at10n 1n the r1cewheat cr0pp1n9 5y~em thu5 earned R5. 8.58 at R.5. Pura and R5. 17.76 at Kanpur (the c05t: 6enef1t rat10 wa5 cMc~ated 0n the 6a515 0f prevNent pr1ce5 wh1ch are R5. 3.6Nk9 f0r r1ce, R5. 3.80/k9 f0r wheat and R5. 7.2~k9 f0r N). 7he t1me-trend e4uat10n5 pre5ented 1n 7a61e 2 5h0wed that y1e1d5 1n the r1ce-wheat cr0pp1n9 5y5tem 1ncrea5ed 9radua11y every year at Kanpu~ wh11e at R.5. Pura the y1e1d 5tarted t0 ded1ne a~er the th1rd cyc1e 0f the exper1ment. C0mpar150n 0f t0ta1 pr0duct1v1ty 0f r1ce-wheat 5e4uence5 1n the 51xth and f1r5t cyc1e 0f the r0tat10n 5h0wed that at Kanpur pr0duct1v1ty wa5 9reater 1n the 51xth cyc1e 6y 9.53% (1n 73) t0 17.93% (1n 77) 0ver the f1r5t cyc1e. 7h15 1ncrea5e 1n pr0duct1v1ty wa5 pr06a6~ due t0 an 1ncrea5e 1n 5011 0r9an1c-C, and ava11a61e P and K c0ntent5 (7a61e 3). 0 n the 0ther hand at R.5. Pura, due t0 a dec11ne 1n the 0r9an1c-car60n c0ntent 0f the 5011, 9ra1n y1e1d dec11ned 1n the 51xth cyde c0mpared t0 that 1n the f1r5t cyc1e 1n a11 the treatment5 except

7aMe 1. We1d5 (t/ha) 0f Ace and wheat c~p5 1n the f1r5t and 5~th ~ d e 5 0f ~c~wheat m~f10n under ~ 5 ~ u e ~ d 1 n 9 w1~ ~ f f e ~ t~me~5 ~ u~wN ~hed~9

7reatment*

At R.5. Pura 71 72 73 74 75 76 77 CD5% At Kanpur 71 72 73 74 75 76 77 CD5% *5ee M~h0d5.

F1r5t cyde

51xth cyde

Mean 0f a11 5k cyde5

R1ce

Wheat

70ta1

R1ce

Wheat

70ta1

R1cc

Wheat

7~a1

4.37 4.43 3.95 4.45 4.48 4.64 4.71 0.092

2.78 2.94 2.96 3.08 4.10 2.87 2.92 0.176

7.15 7.37 6.91 7.53 8.58 7.49 7.63 0.089

3.84 3.61 3.41 4.17 3.93 3.89 4.12 0.064

3.15 3.07 2.95 3.56 3.59 3.29 3.36 0.058

6.99 6.68 6.36 7.73 7.52 7.18 7.48 0.076

4.31 4.21 3.98 4.61 4.46 4.48 4.62 0.033

3.39 3.45 3.33 3.73 3.90 3.46 3.59 0.027

7.70 7.66 7.31 8.34 8.36 7.94 8.21 0.074

3.67 3.63 3.57 3.78 3.87 4.14 3.62 0.036

4.98 4.74 4.60 5.16 5.30 5.52 5.69 0.043

8.65 8.37 8.17 8.94 9.17 9.66 9.31 0.311

4.98 4.79 4.60 5.16 5.30 5.52 5.69 0.051

4.69 4.52 4.35 4.71 4.85 5.08 5.29 0.056

9.67 9.31 8.95 9.87 10.15 10.60 10.98 0.272

4.41 4.29 4.23 4.56 4.69 4.80 4.98 0.045

4.03 4.(17 3.99 4.36 4.14 4.64 4.84 0.073

8.44 8.36 8.22 8.92 8.83 9.44 9.82 0.295

108

R. L. Y a d a v

7aMe 2 71m~trend e4uat10n5 f0r pred1ct1n9 ~ d d (t/ha) 0f ~ce and wheat under d1fferent treatmen~ 0f urea-N app11cat10n w1th re51due recyc11n9 1n a c0nt1nu0u5 r1ce-wheat cr0pp1n9 5y5~m 7~me~*

R1~ 7rend ~uat10n

~ 5 . Pura 71

Y=3.78+0.4~ Y=~22+~201 Y=351 +~511 Y=321 + ~ 7 ~ Y=~84+~565 Y=~01+0.4~ Y=~10+~477

Kanpur 71

Y=2973 Y=2967 Y= 2913 Y=3~13 Y=3.045 Y=3.459 Y= 2655

t--~1 ~ t--~6 t 2 t--~097 t 2 t-~116 t2 t-~098 t2 6 t-~087 t2 6 t - ~ 0 ~ f1

+ 0.472 + 0.453 + 0.485 +0.516 +0.561 + 0.362 + 0.856

t - ~0088 f1 t-~0124 t2 t - ~0246 t 2 t-~111 t2 t-~0145 t~ t-~013 t2 t-- ~0441 t 2

Wh~t 7rend ~uat10n

R 2

0.11 0.28 0.16 0.22 0.15 0.12 0.11

Y=1.84+ Y= 1.93 + Y=2.13 + Y=2.14+ Y=4.10+ Y--1.87+ Y=1.93+

1.227 1.261 1.052 1.213 1.019 1.197 1.294

0.61 055 0.67 0.60 0.59 0.59 0.69

Y=~285 + Y=~133 + Y=%947 + Y=~984 + Y=~233 + Y=3.845 + Y=4.076+

R2

t--0.195 t-- 0.206 t--0.178 t-0.186 t-0.013 t-0.182 t-0.203

t2 t2 t2

t2 t2 t~ t~

~227 t - ~053 t 2 1.205 t - ~ 3 9 2 t 2 L113 t - ~ 2 4 9 t 2 1~753 t - 0 . 6 2 9 t 2 1~107 t--0~354 t: 1.295 t - ~ 0 1 1 2 t 2 1.275 t--0.0091 t 2

0.83 0.88 0.91 0.80 0.48 0.88 0.83 057 0.37 0.30 0.89 0.73 0.88 0.92

*5ee Meth0d5.

74. A t Ludh1ana (a 10cat10n d 0 5 e r t0 R.5. P u r a ) 51dhu and 8ef1 (1989) a150 d1d n0t f1nd a f19n1f1cant effect 0f u n c h 0 p p e d r e ~ d u e 5 0f w h e a t (6 ~ h a ) and r1ce (12 ~ h a ) 1n a r ~ e - w h e a t r0tat10n 0ver f1ve year5. 1n fact, there wa5 a f119ht decrea5e 1n the y1e1d5 0f w h e a t 0ver the year5.

R

~

5

F r 0 m the pre5ent 51x year 5tudy 1t c0u1d 6e 5h0wn that w h e n cr0p5 0f a r1ce-wheat cr0pp1n9 5y5tem are 9r0wn 0n recyc1ed re~due5 0f the preced1n9 cr0p R

~ 1 m p 0 ~ a n t 10 app1y 20 k9 N/ha at 1he t1me c f ref1due 1 n c 0 r p 0 r a t ~ n 0ver and a60ve the r e c 0 m m e n d e d N rate5 1n 5u6-hum1d, m 0 d e r a t e d 1 m a t ~ c0nd1t10n5 5uch a5 that at R.5 Pura. 0 n the 0 t h e r hand, 1n a w a r m e r d1mate, 5uch a5 1hat p r e v ~ e n t at K a n p u ~ app1~at10n 0f n1tr09en at the t1me 0f re51due 1nc0~ p0rat10n m a y n0t 6e r e 4 u ~ e d . H 0 w e v e L 1n t h ~ d 1 m a t ~ c0nd1t10n the r e c 0 m m e n d e d ~ve1 0f n1tr09en 5h0u1d 6e r ~ 5 e d 6y 20 k9/ha f0r 60th the c r 0 p ~ 7he5e p r a ~ e 5 p r 0 d u c e d 7.9% and 16.4% h ~ h e r ~e1d5 ~ 0 m the t 0 t ~ 5 y ~ e m c 0 m p a r e d t0 the f1e1d ~ 0 m the p r e v ~ e n t r e c 0 m m e n d e d N app1~af10n pract1ce5 at R.5. P u r a and K a n p u ~ r e 5 p e ~ e ~ .

7a61e 3. 50ft 0r9an1c-C, and avafa6~ P and K c0n~nt af1er the f1rm and 5~th cyc~5 0f r1ce-wheat cr0pp1n9 5y5~m under re51due recyc11n9 and d1fferent treatment5 0f urea-N 5chedu11n9 7~mem*

At R.5. Pura 71 72 73 74 75 76 77 CD5% At Kanpur 71 72 73 74 75 76 77 CD5% N5=N~ 5~n~m.

0~an~C

(%)

A v ~ a N e P (kNh~

Av~aNe K (kNh~

1 ~de

V1 ~ d e

1 ~de

V1 ~ d e

1 ~de

V1 ~ d e

0.42 0.45 0.46 0.49 0.51 0.51 0.53 0.026

0.38 0.43 0.48 0.48 0.46 0.44 0.45 0.042

10.4 10.7 10.8 10.8 10.7 10.7 10.7 N5

11.5 13.2 14.5 15.2 13.2 15.7 14.2 0.99

92 91 92 92 92 92 92 N5

90 96 93 99 96 93 91 N5

0.16 0.20 0.22 0.20 0.22 0.30 0.30 0.053

0.29 0.33 0.31 0.36 0.34 0.38 0.40 0.039

9.8 9.2 10.9 9.8 9.2 11.2 11.5 1.22

21.4 22.6 24.8 25.8 26.5 24.2 28.4 1.78

14.6 163 160 173 163 160 233 11

188 190 195 200 198 196 201 15

*5ee M ~ h 0 ~ .

~n~m~

~d ~

REFERENCE5 Ak1nyem1, 0. and AdewMe, A. (1984) Effe~ 0f 1ncu6at10n ~mpermu~5 and ~ f f e ~ m 50urce5 0f N and P 0n dec0mp051t~n 0f 5aw du~ ~ 5011.A9~cu1tura1 Wa5~5 11, 293 -306. 8handaf1, A. L , 500d, A, 5 h ~ m ~ K. M. and Rana, D. 5. (1992) 1me9rmed nmf1em mana9ement M f1ce-whe~ ~ e m . J0uma1 0f 1nd~n 50~e~ 0f 50~ 5~ence 40, 742-747. 8hardw~, K. K. R. (1995) Recyd~9 0f cr0p re~due~ 0~cake5 and 0ther ~ant pr0du~5 1n a9r1cu1ture. 1n

Recyc11n9 0f Cr0p, An1mal Human and 1ndu5t~a1 Wa5te5 ~ A9r1cu1ture, ed. H.L5. 7 a n d 0 ~ pp. 9-30. F e ~ e r Deve~pmem and C0n5uRat10n 0r9aM5at10n, New

cr0pp~

1~

D~h1, 1nd1a. HaucL R. D. and 8remne~ J. H. (1976) U5e 0f trace~ f0r 5011 and fe~f1~er n~r09en re5earch. Advance5 ~ A9r0n0my 28, 219-266. Jack50n. M. L. (1973) 50~ Chem1ca1 Ana1y5~. Prent1ce H~1, New D~h1, 1n~a. Jen~n50n, D. 5., F0x R. H. and Rayn~, J. H. (1985) 1nteract10n 6etween fe~f1~er nkr09en and 5011 n1~09en - - 7he 50 c ~ d pf1m~9 effe~. J0urna1 0f 5011 5~ence 3~ 425-444. 51dhu, 8. 5. and 8ef1, V. (1989) Effect 0f cr0p re51due mana9ement 0n the f1e~5 0f ~fferent cr0p5 and 0n 5011 pr0pert1e5. 8101091ca1 Wa5te5 27, 15-27. Yada~ R. L. and Pra5ad. 5. R. (1992) C0n5erv1n9 the 0r9an1c mat~r c0ntent 0f the 5011 t0 5 u ~ n 5u9arcane f1e1d. Expe~men~1A9r1cu~u~ 28, 57-62.