全 文 ：第27卷 第4期 作　物　学　报 V ol. 27, N o. 4
2001 年7月 A CTA A GRONOM ICA S IN ICA July, 2001
Study on the D ynam ic Changes of the D istr ibution and Accumula tion of
N itrogen in D ifferen t Plan t Parts of W hea tΞ
HOU You2L iang1　L. O′B rien2　ZHON G Gai2Rong1
(1Institu te of M aize R esearch, S hanx i A cad em y of A g ricultural S ciences, X inzhou, S hanx i 034000, China; 2 T he U niversity of
S y d ney , P lant B reed ing Institu te, N arrabri, N SW 2390, A ustralia)
Abstract　A field trial w as conducted to exam ine the changes of the distribution and accum ula2
tion of n itrogen in various p lan t parts th roughout the grow ing season. T he results indicated that
sign ifican t geno typ ic differences ex isted fo r the n itrogen con ten t of leaf, stem , peduncle and
chaff, as w ell as the p ro tein con ten t of develop ing grain. T he leaf w as the m ajo r sto rage o rgan
fo r n itrogen and the source of n itrogen fo r grain filling. T he n itrogen con ten t of the leaf w as the
h ighest at the seedling stage, but the h ighest n itrogen accum ulation occurred at the boo ting
stage. Increase of the grain p ro tein con ten t and grain p ro tein yield w as usually accompan ied by
decrease of n itrogen levels of the various p lan t o rgans. A pp lication of n itrogenous fertilizer could
m arkedly increase the p lan t2part n itrogen con ten t and the grain p ro tein con ten t. It w as found
from the 5 samp lings after the boo ting stage that, in most cases, the p lan t2part n itrogen con ten t
w as usually sign ifican tly positively co rrelated w ith grain p ro tein con ten t, indicating that selection
fo r h igher p lan t2part n itrogen are helpful fo r the iden tification of geno types w ith h igh grain p ro2
tein con ten t.
Key words　N itrogen distribution and accum ulation; P lan t o rgans; W heat; Geno type differ2
ences; Grain p ro tein
Imp roving grain p ro tein con ten t and yield po ten tial in w heat is a m ajo r goal of most w heat
imp rovem en t p rogram s. Bo th traits heavily depend upon the capacity of the p lan t to take up n i2
trogen from the so il and translocate it from the vegetative parts to the develop ing grain during
grain filling. N itrogen up take, translocation, partition ing and their relationsh ip to grain p ro tein
have been ex tensively studied in w heat. H allo ran and L ee[ 1 ] repo rted that sign ifican t varietal dif2
ferences ex isted in n itrogen percen tage of the culm , glum e and rach is in the m ature p lan t. N oa2
m an and T aylo r[ 2 ] , in a field experim en t, found that geno types differed fo r p ro tein con ten t in the
upper leaves, ears and peduncles of the w heat p lan t at five grow th stages after ear em ergence.
H igh p ro tein cultivars had h igher leaf p ro tein at m aturity and h igher ear p ro tein at most grow th
stages than their low er p ro tein coun terparts. T he data of Rostam i and O′B rien [ 3 ] revealed sign ifi2
can t differences among geno types fo r p lan t2part n itrogen at Zadok s grow th stage 31[ 4 ] , p lan t2
part n itrogen con ten t being sign ifican tly positively co rrelated w ith grain p ro tein con ten t in most
n itrogen rate comparisons. T hey suggested that use of p lan t2part n itrogen con ten t m ay be an ef2
fective m ethod fo r w heat breeding p rogram s to sim ultaneously increase grain p ro tein con ten t andΞ 收稿日期: 1999212207, 接受日期: 2000209221
Received on: 1999212207, A ccep ted on: 2000209221

grain yield.
　　T he objective of th is study w as to determ ine the dynam ic changes of the distribution and ac2
cum ulation of n itrogen in various p lan t parts, viz. leaves, stem s, peduncles, chaff and the devel2
op ing grain s of four w heat geno types th roughout the grow ing season and to relate these attributes
to the differences in grain p ro tein con ten t.
1　M a ter ia ls andM ethods
A field trialw as conducted at the U n iversity of Sydney, P lan t B reeding Institu te, N arrabri,
in the 1995 season ( It w as located at 30°18′S and 149°18′E, w ith an elevation 212m. D uring
w heat grow ing period, p recip itation w as on ly 259. 2 mm ). Four sem i2w in ter w heat geno types,
i. e. , Cunn ingham , PST 90219, SUN 109A and TM 56, w ere used in th is study, that w ere rep2
resen tatives w ith differen t p lan t2part n itrogen, grain p ro tein level and yield po ten tial, based on
know ledge of p revious perfo rm ance[ 5 ].
T he trial consisted of two block s w ith differen t n itrogen levels created by app lying n itroge2
nous fertilizer at rates of zero and 200 kg N öhm 2. T here w ere four rep lications in each block.
Ammonium nitrate in granular fo rm w as used as the source of n itrogen and app lied as fo llow s:
20% at p lan ting and 40% at Zadock s grow th stages 26～ 27 (m ain shoo t w ith 6～ 7 tillers) and
45～ 50 (boo ts swo llen to first sp ikelet visible) , respectively. Fo llow ing topdressing of the first
n itrogen app lication, sp ray irrigation w as app lied to the en tire experim en tal area. T he second
topdressing w as app lied on 1 Sep tem ber, and 33 mm of rainfall occurred imm ediately after the
app lication. P lo t size w as 7 row s×10 m in length w ith 0. 25 m betw een row s and 0. 5 m betw een
p lo ts. T he trialw as sow n on 8 June at a seeding rate of 30 kg per hectare.
R andom samp les of 50 cm in length of the cen ter four row s each p lo t w ere samp led at two2
w eek in tervals from the 53rd day after sow ing to m aturity. A bove2ground p lan t2partsw ere sam 2
p led eigh t tim es during the grow th cycle. A t each samp ling tim e, samp lesw ere quick ly separated
in to the th ree bo ttom leaves (L 1～ 3) , leaf 4 (L 4) , leaf 5 (L 5). . . . . . . etc. , stem s ( including
leaf sheath) , peduncles (peduncle part uncovered by leaf sheath) , chaff (rach is, glum e, lemm a,
palea and aw n) and develop ing grain. Each p lan t componen t w as imm ediately m icrow aved fo r 2
～ 4 m inutes, then oven2dried at 60 °C for 48 hours to a constan t dry w eigh t basis p rio r to grind2
ing w ith a labo rato ry hamm erm ill fitted w ith a 0. 5 mm screen. T issue n itrogen con ten t of each
componen t and grain p ro tein con ten t w ere m easured by N ear R eflectance Spectrom etry using an
Instalab 600 (D ICKEY2john, co rpo ration, U. S. A. ). A ll data are p resen ted on a dry m atter
basis.
2　Results and D iscussion
2. 1　N itrogen d istr ibution and accum ula tion pa ttern s of plan t parts for four whea t genotypes
with developm en t
2. 1. 1　L eaf n itrogen
A ll leaves of the four geno types invo lved in th is study exh ibited sim ilar patterns fo r changing
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of n itrogen con ten t (% ) w ith tim e. T he unfo lding new leaves possessed the h ighest n itrogen
con ten t, but thereafter their n itrogen con ten t declined p rogressively un til senescence. Generally,
the upper leaves possessed h igher n itrogen con ten ts than the low er leaves at the sam e samp ling
date after stem elongation. T he n itrogen con ten ts of senescing leaves w ere substan tially low er
than the co rresponding green leaves. Sim ilar patterns of leaf n itrogen distribution w ere repo rted
by N oam an and T aylo r[ 2 ].
A nalyses of variance fo r leaf n itrogen con ten t fo r co rresponding leaf num bers of the four
geno types w ere computed in two w ays due to the geno typ ic differences in leaf num bers. Sign ifi2
can t geno typ ic differences in the leaf n itrogen con ten t th roughout the grow ing season ex isted in
21 out of 32 comparisons calculated from low er leaves to upper leaves and in 19 out of 22 from
upper leaves to low er leaves. L ow p ro tein geno type, TM 56, generally show ed the low est leaf n i2
trogen con ten t fo r each leaf compared w ith the o ther geno types.
To tal leaf n itrogen con ten t (% ) among the four geno types w as sign ifican tly differen t up to
the 109th day (around flow ering) , but no difference w as detected during grain filling and m atu2
rity (T able 1). T he h ighest values fo r to tal leaf n itrogen con ten t appeared at seedling stages of
p lan t developm en t, w h ich declined gradually un til the 123rd day after sow ing (around m ilky
stage). R ap id decline occurred from the 123rd day to the 137th day w h ich co rresponded to the
m ilky stage to hard dough stage of grain developm en t, suggesting that a h igh p roportion of the
n itrogen m ay be being translocated to the develop ing grain.
　　Total leaf n itrogen (gö0. 5m 2) accum ulated to a peak around boo ting stage (95th day) , and
then declined un til m aturity (F ig. 1). T here w as a rap id increase betw een the 67th～ 81st days
after sow ing due to rap id grow th during stem elongation. A sligh t decline betw een the 95th～
123rd days (around boo ting stage to m ilky stage) p robably indicated n itrogen movem en t from
the leaves to develop ing ear and grain. A sharp decline in to tal leaf n itrogen betw een the 123rd～
137th days (around m ilky stage to hard dough stage) co incided w ith the period of rap id grain fill2
ing. T he h igh accum ulation and more transfer fo r leaves suggested that the leaf w as the m ajo r
sto rage o rgan fo r n itrogen and source of n itrogen fo r grain filling.
2. 1. 2　Stem nitrogen
N itrogen con ten t (% ) of the stem of the four geno types w as substan tially low er than the
values fo r leaf at all samp ling dates. T here w ere sign ifican t differences among geno types fo r stem
nitrogen con ten t at 7 out of the 8 samp ling dates. T he four geno types disp layed a sim ilar pattern
of change in stem nitrogen con ten t w ith tim e, w ith a rap id decline from the seedling stage to the
123rd day (around m ilky stage) and then a sligh t increase un tilm aturity (T able 1). T he changes
w ere statistically sign ifican t betw een samp ling dates excep t the last two samp lings. T h is result
som ew hat differed w ith that of H allo ran and L ee[ 6 ] w ho, in a phyto tron experim en t, found a de2
cline of stem nitrogen con ten t th roughout p lan t grow th.
T he n itrogen accum ulation (gö0. 5m 2) fo r the stem reached to a peak around boo ting stage
(95th day) , then declined to m ilky stage befo re a increase during later grain filling (F ig. 1). T he
residual levels of n itrogen w ere h igher in the stem than the leaf at m aturity, reflecting that there
5944期　　　HOU You2L iang, et al: Study on the D ynam ic Changes of the D istribution ⋯⋯　　　　　

still w as reserve of n itrogen in the stem that could have been translocated to the grain.
Table 1　　N itrogen content (% ) of plant parts and gra in prote in content (% ) for four
wheat genotypes at var ious sampl ing dates
　 N itrogen content (% ) 　
　
53
　
↓67
　
81
Days after sow ing
↓95 109 123
　
137
　
151
L eaf
Cunningham 4. 92ab 4. 29b 4. 25a 3. 98a 3. 34bc 2. 79 1. 57 1. 24
PST 90219 4. 99a 4. 59a 4. 25a 3. 99a 3. 61a 3. 03 1. 63 1. 32
SUN 109A 4. 91b 4. 37b 4. 32a 4. 01a 3. 52ab 2. 97 1. 61 1. 28
TM 56 4. 81c 4. 24b 3. 93b 3. 79b 3. 27c 2. 89 1. 50 1. 24
L SD (P < 0. 05) 0. 08 0. 14 0. 16 0. 11 0. 25
Significance 3 3 3 3 3 3 3 3 3 3 3 3 3 N S N S N S
Stem
Cunningham 3. 58b 2. 99b 2. 16a 1. 30a 0. 71a 0. 28b 0. 62a 0. 80
PST 90219 3. 77a 3. 28a 1. 82b 1. 16a 0. 76a 0. 42a 0. 69a 0. 81
SUN 109A 3. 53bc 2. 92b 1. 73b 0. 84b 0. 34b 0. 12c 0. 62a 0. 74
TM 56 3. 47c 3. 05b 1. 41c 0. 72b 0. 18c 0. 06c 0. 46b 0. 72
L SD (P < 0. 05) 0. 08 0. 23 0. 28 0. 16 0. 12 0. 08 0. 10
Significance 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 N S
Peduncle
Cunningham 1. 85 1. 78b 1. 04b 0. 95a
PST 90219 1. 91 1. 90a 1. 17a 1. 03a
SUN 109A 1. 83 1. 84ab 1. 22a 0. 96a
TM 56 1. 95 1. 62c 0. 75c 0. 71b
L SD (P < 0. 05) 0. 10 0. 10 0. 10
Significance N S 3 3 3 3 3 3 3 3 3
Chaff
Cunningham 1. 58a 1. 28a 0. 99a 0. 87a
PST 90219 1. 29b 1. 13c 0. 88b 0. 77b
SUN 109A 1. 21c 1. 06d 0. 82c 0. 73c
TM 56 1. 23c 1. 20b 0. 91b 0. 86a
L SD (P < 0. 05) 0. 06 0. 06 0. 06 0. 04
Significance 3 3 3 3 3 3 3 3 3 3 3 3
Grain p ro tein 　
Cunningham 　 10. 55b 12. 26b 13. 40b
PST 90219 11. 86a 14. 14a 14. 93a
SUN 109A 　 10. 66b 12. 31b 12. 83c
TM 56 10. 66b 12. 88b 13. 17bc
L SD (P < 0. 05) 0. 36 0. 64 0. 42
Significance 3 3 3 3 3 3 3 3 3
　　3 , 3 3 , 3 3 3 , Significant at 5% , 1% and 0. 1% p robability levels, respectively; N S, no t significant. ↓, N itrogen
added.
2. 1. 3　Peduncle and chaff n itrogen
T he n itrogen con ten t (% ) of the peduncle and chaff w asm uch low er than that of the leaf at
the sam e samp ling date, but h igher than that of the stem (T able 1). Con ten t of the peduncle
and chaff decreased th roughout grain filling, reflecting the transfer of n itrogen from them to the
develop ing grain. Geno typ ic differencesw ere found fo r peduncle n itrogen con ten t at the last th ree
samp ling tim es and fo r chaff at all four samp ling dates. T he n itrogen accum ulation (gö0. 5m 2)
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fo r peduncle and chaff w as low during the period of grain filling, so n itrogen supp ly by them w as
lim ited.
F ig. 1　　N itrogen accum ulation (gö0. 5m 2) in
various p lant parts for four w heat genotypes
at eigh t samp ling dates
2. 1. 4　Grain p ro tein
Grain p ro tein con ten t (% ) of the four
geno types w as sign ifican tly differen t from grain
fo rm ation un tilm aturity, show ing a gradual in2
crease from the 123rd day (around m ilky stage)
( T able 1 ). Sim ilar results w ere repo rted by
H allo ran and L ee[ 6 ]. H igh p ro tein geno type,
PST 90219, had sign ifican tly h igher grain p ro2
tein con ten t over the period from the 123rd day
to m aturity.
T he grain n itrogen yield (gö0. 5m 2 ) fo r
the four geno types increased rap idly up to the
137th day and then slow ly un tilm aturity (F ig.
1). T he observed rap id increase in the grain n i2
trogen yield co incided w ith a sharp decline in
the n itrogen of the leaf, peduncle and chaff,
p robably as n itrogen w as translocated from
them to the develop ing grain.
2. 2　Effect of n itrogen appl ica tion on the n i-
trogen con ten t (% ) of plan t parts and gra in
prote in con ten t (% )
T here w ere sign ifican t differences betw een
the two n itrogen rates fo r the leaf, stem and
peduncle n itrogen con ten t (% ) at most sam 2
p ling dates and chaff n itrogen con ten t (% ) and
develop ing grain p ro tein con ten t (% ) at all
samp ling tim es (T able 2). A pp lication of n i2
trogenous fertilizer at the rate of 200kg N öhm 2
m arkedly increased the n itrogen con ten t in the
vegetative parts and p ro tein con ten t in the develop ing grain. T he effect of n itrogenous fertilizer
on grain p ro tein con ten t w as consisten t w ith o ther repo rts[ 7, 8 ]. Sign ifican t geno type×n itrogen
in teraction effectsw ere observed fo r p lan t parts in inost cases. T he nature of th is in teraction w as
such that geno types generally show ed an increase in p lan t2part n itrogen con ten t w ith n itrogen ap2
p lication although geno type response varied in m agn itude.
2. 3　Correla tion s between n itrogen con ten t (% ) of plan t parts and gra in prote in con ten t (% )
T he n itrogen con ten t (% ) of various p lan t parts w as sign ifican tly (P < 0. 05) co rrelated
w ith the grain p ro tein con ten t in 28 out of 33 cases betw een the 95th day (around boo ting
7944期　　　HOU You2L iang, et al: Study on the D ynam ic Changes of the D istribution ⋯⋯　　　　　

stage) and m aturity. Correlation coefficien ts ranged from r= 0. 364 (P < 0. 05) fo r the second
uppermost leaf at the 123th day samp ling to r= 0. 838 (P < 0. 01) fo r the stem at the sam e sam 2
p ling date (T able 3). T he flag leaf n itrogen con ten t w as positively co rrelated w ith the grain p ro2
tein con ten t at all samp ling tim es betw een the 95th and 151th days. N itrogen con ten t of the first
uppermost leaf w as positively co rrelated w ith the grain p ro tein con ten t at the 95th, 109th and
123th day samp lings and fo r second uppermost leaf at the 95th, 109th, 123th and 151th day
samp lings. T here w ere sign ifican t positive co rrelations betw een the to tal leaf n itrogen con ten t,
stem n itrogen con ten t and the grain p ro tein con ten t at the last five samp ling dates. Correlations
betw een the peduncle and chaff n itrogen con ten t and the grain p ro tein w ere observed at the
123th, 137th and 151th day samp lings. T he h ighest co rrelation coefficien ts betw een grain p ro
tein con ten t and leaf n itrogen con ten t ( r = 0. 7 6 3 , P < 0. 0 1 ) and stem nitrogen con ten t ( r =
0. 713, P < 0. 01) and the w ho le p lan t ( r= 0. 760, P < 0. 01) befo re flow ering w ere detected at
Table 2　　Effect of appl ication of n itrogen fertil izer on the n itrogen content (% ) of plant
parts and the gra in prote in content (% ) at var ious sampl ing dates
N itrogen
treatm ent
(kgöhm 2) 53 ↓67 N itrogen content (% )Days after sow ing81 ↓95 109 123 137 151
L eaf 0 4. 94 4. 05 4. 08 3. 77 3. 30 2. 72 1. 53 1. 21
200 4. 88 4. 69 4. 29 4. 11 3. 56 3. 12 1. 62 1. 33
Significance N S 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
Stem 0 3. 58 2. 78 1. 79 0. 81 0. 39 0. 07 0. 46 0. 70
200 3. 59 3. 34 1. 77 1. 21 0. 61 0. 38 0. 74 0. 84
Significance N S 3 3 3 N S 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3
Peduncle 0 1. 85 1. 67 0. 93 0. 81
200 1. 91 1. 90 1. 16 1. 01
Significance N S 3 3 3 3 3 3 3
Chaff 0 1. 26 1. 11 0. 81 0. 75
200 1. 40 1. 22 0. 99 0. 87
Significance 3 3 3 3 3 3 3 3 3 3 3 3
Grain p ro tein 0 10. 26 11. 57 12. 48
200 11. 57 14. 19 14. 65
Significance 3 3 3 3 3 3 3 3 3
　　3 , 3 3 , 3 3 3 , Significant at 5% , 1% and 0. 1% p robability levels, respectively; N S, no t significant. ↓, N itrogen
added.
Table 3　　Correlations between plant-part n itrogen content and gra in prote in content at f ive sampl ing dates
P lant parts
　
95
Days after sow ing
109 123 137 151
F lag leaf 0. 4913 3 0. 4623 3 0. 5493 3 0. 3693 0. 4953 3
1 st uppermost leaf 0. 5633 3 0. 4163 0. 4843 3 0. 298 0. 298
2 nd uppermost leaf 0. 4063 0. 3953 0. 3643 0. 317 0. 4213
Total leaves 0. 5933 3 0. 4723 3 0. 5483 3 0. 3863 0. 5683 3
Stem 0. 6053 3 0. 6183 3 0. 8383 3 0. 7303 3 0. 6663 3
Peduncle 0. 193 0. 6123 3 0. 4983 3 0. 6493 3
Chaff 0. 310 0. 3693 0. 6033 3 0. 4723 3
　　3 , 3 3 , Significant at 5% and 1% p robability levels, respectively.
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the 67th day samp ling (around the beginn ing of stem elongation) , indicating that Zadok s grow th
stage 31 is the best stage to samp le fo r determ in ing n itrogen states.
3　Conclusion
T he p resen t study indicates that sign ifican t geno typ ic differences ex ist fo r n itrogen con ten t
of the leaf, stem , peduncle and chaff and fo r grain p ro tein con ten t w hen samp led at differen t
dates during the grow ing season. T hese differences reflect differen t capacities to accum ulate n i2
trogen in the various p lan t parts, suggesting it is feasible to select fo r such differences among
geno types. Certain ly, selecting elevated p lan t2part n itrogen befo re flow ering p rovides a possible
m eans fo r w heat breeders to evaluate paren talm aterials to be used in crosses fo r increasing grain
p ro tein con ten t and possibly to p redict grain p ro tein status in breeding populations. Fo r w heat
grow ers, m easurem en t of p lan t2part n itrogen con ten t p rovides the m eans to enhance n itrogen
m anagem en t in o rder to m ax im ize grain p ro tein and grain yield.
References
1　Loβffler C M , T L Rauch, R H Busch. C rop S cience, 1985, 25: 521～ 524
2　Noam an M M , G A Taylor. E uphy tica, 1990, 48: 1～ 8
3　Rostam iM A , L O′B rein. A ustralian J ournal of A g ricultural R esearch, 1996, 47: 33～ 45
4　Zadoks J C, T T Chang, C F Konzak. W eed R esearch, 1974, 14: 415～ 421
5　Rostam iM A. P h D T hesis. Sydney: The U niversity of Sydney, 1995, 69～ 122
6　Halloran G M , J W L ee. A ustralian J ournal of A g ricultural R esearch, 1979, 30: 779～ 789
7　秦武发, 李宗智. 河北农业大学学报, 1989, 12 (3) : 1～ 6
8　王光瑞, 林晓曼, 周桂英. 见: 庄巧生, 王恒立主编. 小麦育种理论与实践的进展. 北京: 科学普及出版社, 1987. 519～
528
小麦不同器官氮素累积分布动态规律的研究
侯有良1　L. O′B rien2　钟改荣1
(1山西省农科院玉米研究所, 山西忻州, 034000; 2 悉尼大学植物育种研究所, N arrabri, N SW 2390, 澳大利亚)
提　要　在自然条件下, 研究了4个小麦基因型各组织器官氮素的动态分布与累积变化。结果表明: 基
因型间在叶、茎、颖壳、叶鞘未包被的穗下节部分的氮素含量和籽粒蛋白质含量上存在着显著差异。
叶片是前期组织氮素的重要贮存器官和籽粒灌浆中氮素的主要供给源。叶片组织氮素的含量在幼苗期
最高, 而叶氮总量的累积则在孕穗期最多。籽粒蛋白质含量和蛋白质产量的提高伴随着各组织器官氮
素水平的下降。氮肥的施用可显著提高各器官组织氮素的含量, 进而提高籽粒蛋白质含量。孕穗后5次
取样的各器官组织氮素含量与籽粒蛋白质含量绝大多数呈显著正相关。因此, 在小麦品质育种工作
中, 结合组织氮素进行选择, 可有效地提高选择效果, 有助于高蛋白质基因型的育成。
关键词　氮素累积分布; 组织器官; 小麦; 基因型差异; 籽粒蛋白质
9944期　　　HOU You2L iang, et al: Study on the D ynam ic Changes of the D istribution ⋯⋯