29 6 2003 11 871 877 ACTA AGRONOMICA SINICA Vol. 29, No. 6 pp. 871 877 Nov., 2003 3 Ξ ( 225009) 8 6 63, 4 : (1) ; (2) N N, N ; (3), ; (4) ; (5) ; ; N : S511 ;S365 : A Varietal Differences in Response of Main Root Traits to Nitrogen Application Time in Rice ( Oryza sativa L. ) DONG Gui2Chun WANG Yu2Long 3 WANGJian2Gang CAI Hui2Rong CAI Jian2Zhong WU Hua ZHOU Xiao2Dong SHAN Yu2Hua ( Key Lab of Crop Cultivation and Physiology of Ministry of Agriculture, Yangzhou University, Yangzhou, Jiangsu 225009, China) Abstract Pot experiment was conducted to investigate the differences in response of main root traits at heading stage and grain yield of four rice varieties, Ribenqing, Wuyunjing 8, Yangdao 6 and Shanyou 63, to nitrogen application time. Ni2 trogen fertilizer was applied as basal and as top2dressing for tillering, spikelet2promoting and spikelet2sustaining, with no nitrogen application as control. The results showed that : (1) There were significant varietal differences of root traits among different ear2type of varieties. Small2ear type variety presented superiority in number of adventitious roots and total length of the roots per plant, while large2ear type variety had superiority in dry weight of roots per plant and diameter of per adventi2 tious root ; (2) Response of number of adventitious roots per plant to nitrogen application time was similar in four varieties, i. e. earlier application was more effective. Basal N and top2dressing significantly increased dry weight and total length of adventitious roots per plant, all varieties involved in this study showed the same tendency, while significant differences in response of that to ear fertilizer were observed among the varieties. There was no significant effect of N application time on diameter of per adventitious ; (3) The positive effect of N applied during ear development on dry weight of roots & total length of the roots per plant in large2ear type variety at heading stage was greater than that in small2ear type variety, and spikelet promoting was more effective ; (4) As ear2type enlarged and grain yield increased, the number of root traits affect2 ing grain yield increased gradually ; (5) Results obtained indicated that improving the development of adventitious roots per Ξ : (00KJB21007) : (1965 - ), E2mail : gcdong @mail. yzu. edu. cn 3 : (1955 - ),,,,Tel :051427979339 Received( ) :2002208208, Accepted( ) :2002212201.
872 29 plant was important to increase root accumulation at heading stage and grain yield, and all varieties involved in this study showed the same tendency. Key words Rice ; Root traits ; Yield ; N application time [1 4 ] 209 mg kg - 1 ) 17. 5 kg, [5 9 ] 1. 2 [4,8,10 ] 1. 2. 1 [9,11 ] 2 (6 ), [10 ] [12 ] 1. 2. 2 6 4 (12 ) (, ) 2 8 6 63 4 2. 1 8 63 6 12. 17 8. 90 8. 17 6. 85 ( 1) 1. 39 2. 66 3. 47 4. 18 g 1 67. 7 104. 2 134. 2 155. 3 ( 1. 1 1) 1998 11. 3 10. 5 10. 2 8 6 8. 6 4. 6 ( ) 63 (CK) ( 1 0. 05 ) ( 5 ) ( 0. 01 30 ) ( 20 ) 2. 2 2 g ( 20 cm, N 17 kg),5 11 2. 2. 1,6 4 4. 8 2 N 3 1, > > [2,12,13 25 cm 30 cm, ( > ] 1147 % 102 mg kg - 1 18 mg kg - 1 Table 1 1 ( Varietal differences of panicles per blant and traits adventitious roots per panicle in rice 8 63 6 Ribenqing Wuyunjing 8 Shanyou 63 Yangdao 6 Panicles per plant 12. 17 a 3 8. 90 ab 8. 17 b 6. 85 b Number of adventitious roots per panicle 34. 75 a 36. 63 a 42. 73 a 48. 17 a Total length of the roots per panicle (cm) 608. 88 a 653. 01 a 837. 18 a 936. 80 a Dry weight of roots per panicle (g) 0. 26 C 0. 45 BC 0. 72 BA 0. 78 A 3 : LSD 1 %( ) 5 %( ) Significant test by LSD, figures with the same letter indicates no significant difference and that with different letter indicate significant at 1 %(capital letter) and 5 %(small letter), respectively. The same below.
6 : 873 Fig. 1 1 Varietal differences in dry weight & number of grains per panicle in rice Ribenqing 8 Yuyunjing 8 6 Yangdao 6 63 Shanyou 63 3 3 0101 Significance at 0101 level., ), 63 8 6 N N 2. 2. 2 3 6 8 63,, 63 8 6 ) N ( 2. 2. 3 ) 4 (, Table 2 2 Varietal differences in response of number of adventitious roots per plant to N application time ( number plant - 1 ) No nitrogen Basal N Tiller N Spikelet promoting Spikelet sustaining Means of varieties Ribenqing 318. 3 b 475. 7 a 456. 9 a 456. 8 a 406. 3 ab 422. 8 A 8 Wuyunjing 8 239. 7 C 399. 7 A 386. 5 A 304. 3 B 299. 3 B 325. 9 B 6 Yangdao 6 261. 4 B 426. 0 A 400. 6 A 297. 0 B 264. 7 B 329. 9 B 63 Shanyou 63 253. 8 C 429. 7 A 405. 7 A 330. 0 BC 325. 8 C 349. 0 B Means of treatments 268. 3 C 432. 8 A 412. 4 A 347. 0 B 324. 0 B Varieties treatments 3 3 0. 01 Significance at 0. 01 level. 3 3 Table 3 3 Varietal differences in response of total length of roots per plant to N application time ( cm plant - 1 ) No nitrogen Basal N Tiller N Spikelet promoting Spikelet sustaining Means of varieties Ribenqing 6281. 0 a 8650. 8 a 8927. 6 a 6961. 6 a 6219. 5 a 7408. 1 A 8 Wuyunjing 8 4938. 4 b 6104. 4 a 6620. 3 a 5690. 3 ab 5696. 5 ab 5810. 0 B 6 Yangdao 6 5467. 3 C 8072. 7 A 7162. 9 AB 6265. 9 BC 5116. 6 C 6417. 1 BA 63 Shanyou 63 5271. 8 b 7352. 2 a 7109. 3 a 7449. 6 a 7002. 0 a 6837. 0 BA Means of treatments 5489. 6 C 7545. 0 A 7455. 0 A 6591. 9 BA 6008. 7 BC Varieties treatments 3 3 0. 05 Significance at 0. 05 level.
874 29 Table 4 4 Varietal differences in response of dry weight of roots per plant to N application time ( g plant - 1 ) No nitrogen Basal N Tiller N Spikelet promoting Spikelet sustaining Means of varieties Ribenqing 3. 00 b 3. 21 ba 4. 34 a 2. 91 b 2. 66 b 3. 22 C 8 Wuyunjing 8 3. 77 b 3. 78 b 4. 83 a 3. 69 b 3. 98 b 4. 01 B 6 Yangdao 6 4. 31 B 7. 22 A 6. 72 A 4. 46 B 4. 07 B 5. 35 A 63 Shanyou 63 4. 89 b 6. 00 a 6. 85 a 6. 15 a 5. 68 ba 5. 92 A Means of treatments 3. 99 C 5. 05 BA 5. 68 A 4. 30 BC 4. 10 C Varieties treatments 3 3 3 3 0. 01 Significance at 0. 01 level. Fig. 2 2 Varietal differences in response of traits of per adventitious root to N application time No N Basal N, Tiller N Spikelet Promoting Spikelet Sustaining.,The same below. 63 8 63 N 6, 63 8 63 2 N 6, 8 63, 6 8 2. 3 N ( 3) 2. 2. 4 > > > 2,, 8 6
6 : 875 Fig. 3 3 N Effects of N application time on grain yield in rice 2. 4 4 6 017303 3 ( ) 018003 3 3 ( ) 018489 3 3 ( 8 ) 017667 3 3 ( 6 ) 018944 3 3 ( 63) - 015009 ( ) - 012140 ( 8 ) ( 4) - 014461 ( 6 ) - 014309 ( 63) 8 6 63 012269 ( 010593 g 010759 g 010864 g 010964 g ; ) - 013044 ( 8 ) - 010442 ( 6 ) 018709 3 3 ( - 012091 ( 63), 8 ) 016567 3 ( 6 ) 016914 3 ( 63) ( 5), 1 cm 8 6 63, 010046 g 010053 g 010048 g ; 4 Fig. 4 The correlation between number of adventitious roots per plant and yield 5 Fig. 5 The correlation between total length of roots per plant and yield, ( 8 6 63) ( 6 ), 3 311 [12 ] 6
876 29 ( 4 5) 8 6 63 8 63 6 [12 ] 017915 3 3 ( 8 ) 016526 3 ( 63) 018317 3 3 ( 6, ),, 019122 3 3 ( 6 ),,,, 1 3 4 6 63 8 (, ) 6 8 6, 8, (,, ) ( ),, 1 6 > 63 > 8 > 1 4 1 ( ),! References N N 312 [1,2,12 17 ], [12 ] [1 ] Chen J ( ). Comparative study on roots of indica and japonica 6 varieties and their hybrids. Journal of Shenyang Agricultural University ( ), 1991,22(suppl) :99 105 [2 ] Shi Q2H( ). Studies concerning the effects of root characteristics on the formation of yield in hybrid rice and large2panicle type varieties., Acta Agricultural University Jiangxiensis ( ), 1984,2 :71 79 [3 ] Wang Y2L ( ),Chen L ( ),Yao Y2L ( ),Li T2Y ( ), Jiang J2M( ),Cai J2Z( ). The varietal dif2 ference in rooting and root activity of rice. Journal of Jiangsu Agricul2 tural College ( ),1994,15(1) :11 16 [4 ] Tanaka S, Yamauchi A, Kono Y. Root system morphologh of four rice
6 : 877 cultivars : response of different component roots to nitrogen application. Jpn J Crop Sci, 1995,64(1) :148 155 [5 ] Ni W( ). Effects of light on root growth and grain yield & root physiological activity in rice. Acta Agronomica Sinica ( ), 1983, 9(1) :29 33 [6 ] Ling Q2H( ),Zhang G2P( ),Zhu Q2S( ),Cai J2 Z ( ),Chao X2Z( ). Response of root system of rice to water and nutrients. Journal of Jiangsu Agricultural College ( [13 ] Wang Y2L ( ),Cai J2Z( ),He J2S( ),Chen L ),1990, (1) :23 27 [7 ] Lin W( ),Li Y2Z( ),Jiang Z2W( ), Yang H2J ( ). Reaction of morphology and function of hybrid rice root system to nutrient in solution. ),2000,15(1) :1 6 Fujian Journal of Agricultural Science ( [ 8 ] Dong G2C( ), Wang Y2L ( ),Wu2H( ),Wang J2G ( ),Cai H2R( ),Zhang C2S( ), Cai J2Z ( ). Effect of nitrogen supplying levels on the development of roots in rice ( Oryza sativa L. ). Jiangsu Agricultural Research ( at different nodepositions and their relation to the yield formation in ),2001,22(4) :9 13 [9 ]., (4) :3 11., 1976, [16 ] Shi Q2H( ), Li M2Y( ), Xu Y2Q ( ),Zhang (45) :99 116 [10 ] Wang Y2L ( ),Yao Y2L ( ), Liu B2Y( ),Lu Z2 L ( ),Huang J2Y( ),Xu J2K( ), Cai J2Z ( ). Effect of nitrogen supplying levels and timings on the develop2 ment of roots in hybrid indica rice. Acta Agronomica Sinica ( ), 1997,23(6) :699 706,1963,32 :163 180 [11 ]. cultural Sinica ( ), 1997,30(4) :61 67,. [12 ] Dong G2C( ), Wang Y2L ( ), Huang J2Y( ), Wu2H( ),Yang L2X( ),Shan Y2H( ), Yao Y2L ( ),Cai J2Z ( ). Effects of nitrogen fertilizer applied at different growth stages on root growth and grain yield of yangdao 6 rice (Oryza sativa L. ). ),2001,22(3) :13 17 Jiangsu Agricultural Research ( ( ), Xu J2K ( ), Bian Y ( ). The relationships between spikeleg2root activity and grain filling and ripening in rice ( Oryza sativa L. ). Acta Agronomica Sinica ( ), 1992,18 (3) :81 89 [ 14 ] Ling Q2H( ),Zhang H2C( ),Su Z2F( ),Ling L ( ). Leaf2age2model of Rice ( ). Beijing : Sci2 ence Press,1994. 127 143 [15 ] Ling Q2H( ),Ling L ( ). Studies on the functions of roots rice plants. Scientia Agricultura Sinica ( ),1984,17 P2L ( ). Preliminary Studies on the relationship between the characteristics of roots and shoots in rice. Acta Agricultural University Jiangxiensis ( ), 1995,17(2) :110 115 [17 ] Shi Q2H( ),Huang Y2J ( ),Li M2Y( ). Stud2 ies on the heredity of root characteristics of and correlation between the characteristics of roots and upper2ground parts in rice. Scientia Agri2 ( ) ; ;, ; : :,16 64 5. 00 :82-130 : 18 (100026) : (010) 64194988 : (010) 64195129, E2mail : shijienongye @ccap. com. cn