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991.
X.J. Fang * L.R. Jiang Hainan Institute of Tropical Agricultural Resources Sanya China Life College Xiamen University Xiamen Fujian China. 《分子植物育种》2007,5(2):209-210
Rice appearance trait is mainly mean grain length (GL), grain width (GW), ratio of length and width (L/W), chalkiness (CH) and transparence (TR). Appearance is the first impression, and rice appearance traits effect significantly the value of commodity. Hybrid rice is relatively low quality, especially on rice appearance quality,which restricts partially its extend and badly export of hybrid seed and rice in China.Shanyou 63, the most famous hybrid rice combination of China, could not be also sustainable application because of its poor qualities. In this studies, We attempt to improve appearance quality of the elite rice maintainer of Zhenshan 97B by using molecular approach of genomic interval targeted introgression. Three F2 populations were constructed to study the classical and molecular genetic of rice appearance traits, at the same time, molecular marker-asisted toimprove the main maintainer line, Zhenshan 97B were performed. There some following results:Three F2 populations were constructed based on crosses of Guangluai 4×Jiafuzhan (GJ popu.), Minghui 86×Jiafuzhan (MJ popu.) and Zhenshan 97B×Jiafuzhan (ZJ popu.). ZJ popu and GJ popu were produced to reconstruct the linkage maps related with rice appearance traits based on BSA, and detect QTL of target traits based on IM.In ZJ popu, 9 QTLs of target traits were detected. The interval, RM169~RM516 on Chromosome 5, was genetic locus of GW, L/W, CH and BW, and the explained variances were 10.9%, 14.9%, 12.0% and 14.2%, respectively.RM214 on chromosome 7, RM339 on chromosome 8 were genetic loci if CH and BW, and the explained variances were 9.4%, 10.0%, 11.0% and 12.1%. besides there is a genetic locus, RM347, of G/W on chromosome 3, and the explained varance was 10.3%. In GJ popu, 5 QTLs of rice appearance traits were detected. The interval, RM169-RM516 on Chromosome 5, were also the genetic loci of GW, CH and BW, and the explained variances were 9.0%, 12.5%, and 13.6%, respectively. RM264~RM80 on chromosome 8 was the genetic loci of GW amd L/W,and the explained variances were 14.7% and 13.4%. The genotypes of all QTLs, except RM214, from Jiafuzhan contributed to improving riee appearance traits.The research was to improve the rice appearance quality of Zhenshan 97B by introgressing QTLs of rice appearance traits from Jiafuzhan, a donor parent, by means of MAS in the process of recurrent backcrossing, 4 SSR markers were used to detect the target genotypes from donor parent, and 70 SSR primers to identify the genetic background of recurrent parent. Consequently, there were 19 target individuals in BC3, in which the mean value of GL, GW, L/W, CH and BW were 6.06±0.04mm, 2.50±0.02mm, 2.43±0.02, 29.5±2.7 and 29.4±2.7%, respectively,and the mean homologous degree (HD) to recurrent parent is up to 98.22%. Compared to Zhenshan 97B, GL, CH and BW decreased 0.17 mm, 34.9% and 34.5% respectively and however L/W increased 0.19. which accounted separately for 25.37%, 54.79%, 54.57% and 10.50% of thedifference of every trait between two parents. It is very luckly to find a individual, 13BC2-3BC3 line, whose GL, GW, G/W, CH and BW were 6.04 mm, 2.43 mm, 2.49,2.5% and 2.5% separately, There is very important signification for it to be used in hybrid rice breeding improving appearance traits. In the research, MAS efficiency of 3 loci (with 4 markers ) was 5.68% and coincident degree was 73.08%. 相似文献
992.
993.
太湖稻区水稻条纹叶枯病暴发原因及控制技术 总被引:2,自引:0,他引:2
水稻条纹叶枯病是太湖稻区水稻生产上新上升的重大病害,由媒介灰飞虱传毒产生.2004年麦田越冬代灰飞虱达123万头/hm2,比去年同期增加10~20倍,带毒率30.2%,同比增加5.5个百分点,5月底小麦田1代灰飞虱高达1500万~3000万头/hm2,比常年猛增150~200倍,水稻产量损失10%左右;在前中期不施药区内,香粳14等8个主栽品种产量损失率为21.11%~39.68%;春江06等9个具特异抗性的品种(系)产量损失率为0~5.16%,损失率比前者减少94.08%.采用优质、高产的抗性品种,加强虫情预、测报,推广治虫控病的综合防治技术,能经济有效地控制水稻条纹叶枯病的危害. 相似文献
994.
夏玉米增产综合指标和技术措施 总被引:1,自引:0,他引:1
夏玉米增产综合指标和技术措施吴智泉,路金双(河北省衡水地区农业技术推广站053000)杜新红,杨子良,吴志强(阜城县农技推广站)(衡水地区农业学校)我们于1989~1993年针对本区自然资源特点,粮食生产条件和夏玉米生产中普遍存在的问题,运用系统工程... 相似文献
995.
以羊奶粉为原料,选取4种由保加利亚乳杆菌和嗜热链球菌组成的乳酸菌基础发酵剂对羊乳进行发酵,通过测定发酵过程中羊乳的活菌数、酸度、pH值及黏度,研究这4种发酵剂的发酵特性.结果表明,在40 ℃条件下,YO-MIX499,YO-MIX300,FVV121,YO-MIX883四种基础发酵剂发酵羊乳,12~18 h活菌数达到最大值,分别为11.00×108,6.74×108,6.89×108,7.02×108 CFU/mL;酸度和黏度均随发酵时间的延长而增大,其中YO-MIX883产黏性最好,YO-MIX300产酸性最好. 相似文献
997.
998.
硬粒小麦的多倍体突变体是生产非还原配子的一种基因型。本文的首要目的是测试该突变体生产5倍体杂种的能力,并测定这些杂种的恢复频率;第二个目的是测试该突变体与黑麦和T.monococcum的杂交能力(以种子结实%计算);第二个目的还包括测 相似文献
999.
从2001年开始,宜昌市夷陵区全面启动起止期18a的退耕还林工程。全区规划面积2万hm2,其中退耕还林1.33万hm2,荒山造林6666.7hm2。工程涉及12个乡镇的321个村,4.1万农户,20多万农民,概算总投资4.37亿元。根据总体规划测算,全区退耕还林工程中可以新增柑桔、茶叶、板栗、核桃、银杏、木本药材、猕猴桃等为主的高效经济林6667hm2,年可新增收入过亿元。退耕还林工程的实施,不仅为全区,特别是西北山区农民脱贫致富带来了新机遇,而且成为全区农业经济发展的又一新的增长点。茶叶,作为夷陵区六大支柱产业之一,不仅具有调节气候、涵养水源、保持水土… 相似文献
1000.
对芝麻的几个器官和花序进行了观察和研究。芝麻叶腋内2个刺状物为苞叶。花冠筒内丝状物为退化雄蕊的短花丝。子房基部周围环物为花内蜜腺。单蒴型芝麻果柄两侧圆形物为退化花的遗留芝麻花序定名为二歧聚伞花名为二歧聚伞花序。 相似文献