The grain yield, the characteristics of conducting tissue in the first internode and their relations with the grainfilling were analyzed by using four hybrid rice combinations derived from R1126 as materials and Shanyou 63 as a control. The results showed that the grain yield of the four hybrid rice combinations was 7.43% to 24.23% higher than that of Shanyou 63. Increased total grain number and filled grain number per panicle attributed to yield increase. Compared with Shangyou 63, hybrid rice combinations derived from R1126 had advantages in the neck diameter, area of stem wall, ration of stem wall to cross, No. of vascular bundles（VB）, total area of VB, total area of phloem,the ratio of VB area to phloem area as well as conducting tissue activity, while had lower ratio of spikelet number to area of VB, ratio of spikelet number to area of phloem, ratio of total sink to area of VB， ratio of total sink to area of phloem，ratio of full grain weight to area of VB, ratio of full grain weight to area of phloem, and the organic material transfer to panicle was fluency. The derived hybrid rice combinations were characterized by greater initial grainfilling potential (R0), maximum grainfilling rate (GRmax) and mean grainfilling rate（GRmean）, earlier maximum grainfilling rate (Tmax) , shorter active grainfilling period (D) and effective grainfilling time (T99), faster grain filling and reasonable filling dynamics, smaller dvalue of final weight of a kernel (A) between superior and inferior grains, which contributed to good grainfilling. The correlation analysis showed that the ration of spikelet number, grain weight, total sink capacity to area of phloem were negatively correlated with GRmax and GRmean of SG and IG, and grainfilling rate. And D,T99 , Tmax were positively correlated with them as well as conducting tissue activity. Conducting tissue in the first internode had closed relationship with grainfilling, improving its characteristics could be beneficial to grain filling.
\[1\]Horie T, Shiraiwa T, Homma K, et al. Can yields of lowland rice resume the increases that they showed in the 1980s? Crop Sci, 1999, 36:15521559.
\[2\]Peng S, Gassman K G, Sheehy J,et al. Yield potential trends of tropical rice since release of IR8 and the challenge of increasing rice yield potential. Crop Sci, 2003, 39:14321437.
\[3\]朱德峰,程式华,张玉屏,等.全球水稻生产现状与制约因素分析.中国农业科学, 2010, 43(3): 474479.
\[4\]陈温福,徐正进.水稻超高产育种理论与方法.北京.北京科学出版社, 2008： 910.
\[5\]杨仁崔,杨惠杰.国际水稻研究所新株型稻研究进展.杂交水稻,1998, 13(5): 2931.
\[6\]袁隆平.超级杂交水稻育种研究的进展. 中国稻米, 2008(1): 13.
\[7\]程式华.中国超级稻育种研究的创新与发展. 沈阳农业大学学报,2007, 28(5): 647651.
\[8\]吴桂成,张洪程,钱银飞,等.粳型超级稻产量构成因素协同规律及超高产特征的研究.中国农业科学, 2010, 43(2): 266276.
\[9\]彭桂峰,李义珍,杨高群. 两系杂交稻培矮64S/E32的超高产特性与栽培研究.Ⅰ：超高产的决定因素.杂交水稻，2010,15: 9596.
\[10\]曹显祖,朱庆森,杨建昌,等.江苏中籼品种产量源库关系与株型演变特征的研究(摘要)//凌启鸿.稻麦研究新进展.南京:东南大学出版社,1991:114115.
\[11\]黄育民,陈启锋,李义珍.我国水稻品种改良过程库源特征的变化.福建农业大学学报,1998,27(3):271278.
\[12\]张耗,谈桂露,薛亚光,等.江苏省粳稻品种近60年演进过程中产量与形态生理特征的变化.作物学报,2010,36(1):133140.
\[13\]Gendua P A, Yamamoto Y, Miyazaki A, et al. Responses of yielding ability, sink size and percentage of filled grains to the cultivation practices in a Chinese largepanicletype rice cultivar, Yangdao 4. Plant Prod Sci, 2009, 12(2): 243256.
\[14\]Gendua P A, Yamamoto Y, Miyazaki A,et al. Effects of the tillering nodes on the main stem of a Chinese largepanicletype rice cultivar, Yangdao 4, on the growth and yieldrelated characteristics in relation to cropping season. Plant Biotechnol J, 2009, 12(2): 257266.
\[15\]Yang L X, Huang J Y, Yang H J, et al. The impact of freeair CO2 enrichment (FACE) and N supply on yield formation of rice crops with large panicle. Field Crops Res, 2006, 98: 141150.
\[16\]Li M, Tang D, Wang K J, et al.Mutations in the Fbox gene larger panicle improve the panicle architecture and enhance the grain yield in rice. Plant Biotechnol J, 2011, 9(9): 10021013.
\[17\]杨建昌,朱庆森,王志琴,等.亚种间杂交稻光合特性及物质积累与运转的研究.作物学报,1997, 23(1):8288.
\[18\]庄宝华,林菲,洪植潘.两系亚种间杂交稻结实生理调节的研究.中国水稻科学, 2004, 18(2): 111114.
\[19\]徐正进,陈温福,曹洪任,等.水稻穗颈维管束数与穗部性状关系的研究. 作物学报, 1998, 24(1): 4754.
\[20\]邓启云,马国辉.亚种间杂交水稻维管束性状及其与籽粒充实度关系的初步研究.湖南农学院学报，1992， 12(2): 711.
\[21\]马均,马文波,周开达,等.水稻不同穗型品种穗颈节间组织与籽粒充实特性的研究.作物学报, 2002, 28(2):215220.
\[22\]刘立军,谢光辉. 稻穗颖花开花日序对籽粒胚乳细胞数和米质的影响.中国水稻科学, 2001,15(2):119124.
\[23\]袁继超,丁志勇,俄胜哲，等. 源库关系对水稻籽粒灌浆特性的影响.西南农业学报，2005，18（1）：1519.
\[24\]程旺大,张国平,姚海根，等.密穗型水稻品种的籽粒灌浆特性研究.作物学报，2003，29（6）：841846.
\[25\]谢光辉,杨建昌,王志琴,等. 水稻籽粒灌浆特性及其与籽粒生理活性的关系.作物学报, 2001,27(5):557565.
\[26\]黄璜.水稻穗颈节间组织与颖花数的关系.作物学报,1998, 24(2):193200.
\[27\]屠乃美，周文新，黄见良，等. 水稻灌浆结实期减源疏库对源库关系的影响.中国水稻科学,1998,12(增刊):2128.
\[28\]朱庆森,曹显祖,骆亦其.水稻籽粒灌浆的生长分析.作物学报, 1988, 14(3): 182193.
\[29\]顾世梁,朱庆森,杨建昌,等. 水稻材料籽粒灌浆特性的分析.作物学报, 2001, 27(1): 714.
\[30\]朱庆森,王志琴,张祖建,等. 水稻籽粒充实程度的指标研究.江苏农学院学报,1995, 16(2): 14.
\[31\]Yang J C, Zhang J H. Grain filling problem in filling problem in “super” rice. J Exp Bot, 2010, 61:15.
\[32\]Zhang H, Tan G L, Yang L N,et al. Hormones in the grains and roots in relation to postanthesis development of inferior and superior spikelets in japonica/indica hybrid rice. Plant Physiol Biochem, 2009, 47:195204.
\[33\]陈锦清.稻穗各部位维管束影响谷粒发育成熟的研究.浙江农业大学学报,1983, 9(2):145158.
\[34\]明东风,马均,马文波,等.水稻不同穗型品种穗部枝梗维管束与籽粒充实特性的研究.西南农业学报， 2004(04):409412.
\[35\]马均，周开达.亚种间重穗型杂交稻穗颈维管束与穗部性状的关系.西南农业学报，2001,14(3):15.
\[36\]徐正进,陈温福,曹洪任,等.水稻穗颈维管束与穗部性状关系的研究.作物学报,1998,24(1):4757.
