栽培稻种间杂交改良云南粳稻品种研究

为引入非洲栽培稻的有利基因以丰富云南粳稻的遗传基础以达到培育高产、抗病、抗逆云南粳稻品种的目的,利用179个非洲栽培稻品种作母本与6个云南粳稻杂交,并用相应父本回交后形成F1、BC1F1、BC2F1、BC2F2群体,同时对滇粳优1号作轮回亲本的组合在BC2F1中每组合随机用5~10株回交至BC3F1。研究表明,F1及BC1F1的自交结实率为0,种间杂种不育是非洲栽培稻与亚洲栽培稻种间杂交最主要的生殖障碍;但回交至BC2F1自交结实率即达到7.9％, BC3F1的平均结实率为14.6％,在BC2F1选结实率在10％以上的植株自交1次,BC2F2的结实率即为42.8%,变幅15%~80%;表明杂种不育模式符合“单位点孢子体 配子体互作不育”。在BC2F2群体中,10.7％的组合的综合表现优于轮回亲本。大规模育种实践表明,通过两次回交,再自交2~3代,种间杂种不育的障碍基本可得到克服,并可引入非洲栽培稻的有利基因。     

四倍体及二倍体毛泡桐截干再生特性研究

为掌握人工诱导四倍体毛泡桐保持多倍体特性情况及毛泡桐截干再生特性,笔者以5a生四倍体及二倍体毛泡桐截干再生苗为材料,对截干再生苗的倍性、出芽数、生长速率、叶片特性、叶绿素含量及光合特性等进行研究.结果表明:四倍体毛泡桐截干再生苗能很好地保持其多倍体倍性,相对于二倍体来说,出芽数较少,生长较缓慢;气孔增大,气孔密度降低;...     

毛泡桐开花对树体营养消耗的影响

通过对泡桐开花过程中相关生理及生态指标的测定,探讨整个开花物候期过程中花器官营养消耗动态,为制定泡桐的适生栽培技术提供依据。试验表明,泡桐在花器官形成和开花过程中,要从根和枝中大量调集贮藏的无机和有机营养物质。小花开绽前对树木进行修剪比在盛花期进行修剪花器官干物质消耗减少53%,粗蛋白消耗减少56%,全糖消耗减少71%。     

青藏高原农田生态系统碳平衡

为探讨青藏高原农田生态系统碳平衡规律及其影响因子 ,并揭示其对全球含碳温室气体源、汇变化的贡献与响应 ,1 998～ 1 999连续 2年在拉萨农业生态站农田用静态箱法和生物量取样法开展土壤—植被界面CO2 吸收与排放的试验研究。农作物生长季 ,以冬小麦为例 ,生长前期 (从播种到拔节 )土壤碳排放量高于植被碳固定 ,生长后期 (灌浆到成熟 )则是植被碳固定高于土壤碳排放量 ,从全年来看 ,土壤碳排放量略高于植被碳固定     

15%麦极WP对日本看麦娘等麦田恶性禾本科杂草的防治效果

采用盆栽方法,研究了15%麦极WP对日本看麦娘、野燕麦、雀麦和节节麦4种麦田恶性禾本科杂草的防治效果.结果表明:麦极300～450g/hm2处理能有效控制2～6叶期的日本看麦娘和野燕麦,但对节节麦和雀麦防效不大.经济用量为300g/hm2,对野燕麦和日本看麦娘的防治效果可分别达到100%和93.2%以上.     

龙眼胚性悬浮细胞原生质体培养及其体胚发生再生植株

以“红核子”、“东壁”、“十二月龙眼”等龙眼品种的胚性悬浮细胞为起始材料分离原生质体,采用液体浅层培养、包埋悬浮培养等方式,进行原生质体培养与植株再生研究。研究结果表明,海藻酸钙包埋悬浮振荡培养(50r/min)是龙眼悬浮细胞原生质体培养的适宜培养方式,在含有多种生长调节剂的改良MS培养基(MP6)上,再生小克隆的形成频率可高达5%;采用龙眼胚性愈伤组织体胚诱导、成熟和萌发的优化方案,原生质体再生小克隆分化子叶形胚状体的频率达100%,萌发植株的频率一般大于45%。      

栽培稻种间近等基因系杂种育性研究

 为了研究亚洲栽培稻与非洲栽培稻种间杂种不育的遗传基础，以亚洲栽培稻品种WAB56-104为测验种与来自种间回交组合WAB56-104/CG14//WAB56-104///WAB56-104的14个种间近等基因系测交，对亲本及杂种的花粉及小穗育性研究表明，这14个近等基因系带有来自非洲栽培稻品种CG14的3个互不等位的配子消除位点和2个互不等位的花粉不育基因位点, 其中至少有2个配子消除位点未曾报道过。     

Grain Protein Content of Interspecific Progenies Derivedfrom the Cross of African Rice (Oryza glaberrima Steud.) and Asian Rice (Oryza sativa L.)

Abstract

The protein contents of the grain of 50 interspecific progenies developed from the cross between WAB56-104, an Oryza sativa variety, and CG 14, an Oryza glaberrima line, were investigated. In contrast to the higher protein content of O. glaberrima than O. sativa on the average, the protein content of CG 14 was always lower than that of WAB56-104. However, judging from the average of three seasons, 72% of the interspecific progenies had a higher protein content than the mid-parent and 50% of them had a higher protein content than WAB56-104. Although the actual values of protein content of the interspecific progenies were significantly different among the seasons, a highly significant correlation was always observed in protein content between any two of the three seasons. Protein content therefore was considered character of each interspecific progeny though it was also affected by environment. A significant correlation was not observed between paddy yield and protein content in any season; several interspecific progenies showed higher protein content and paddy yield than the mid-parents. A low paddy yield is likely to be associated with high protein content through physiological regulation without a genetic linkage between the two traits. However, the results suggest that the transgressive segregation of protein content observed in the interspecific progenies is attributed not to this physiological regulation but to a certain mechanism to concentrate protein in grains with a genetic background.     

同源四倍体水稻与非洲栽培稻杂交的后效性研究

利用亚洲栽培稻中的4份同源四倍体水稻(O.sativa,2n=4x=48)和相应的4份二倍体水稻(O.sativa,2n=2x=24)为母本,以4份非洲栽培稻(O.glaberrima,2n=2x=24)为花粉供体进行远缘杂交后,对其杂种后代的分离动态进行了研究.结果表明,不同倍性的普通栽培稻与非洲栽培稻之间杂交后代的结实率以二倍体普通栽培稻的较高.在配制的32个杂交组合中,其杂种第1代群体均表现出明显的营养生长优势.从群体的生长势来看,杂种第2代群体比杂种第1代群体要弱一些;在杂种第2代群体中,以同源四倍体水稻为母本的杂交组合的分离现象比以二倍体水稻为母本的杂交组合的分离现象更明显.在各杂交组合的第3代群体中,从植株的株叶形态和生育期来看,株系间的差异和株系内的变异依然很明显,变异频率更宽,变异种类更多.在普通栽培稻与非洲栽培稻的杂交组合中,育性变异、生长势变异、株叶形态变异、染色体变异和结实性变异等是较易发现的变异现象.     

麦田茼草春季化学防除技术研究

通过田间试验筛选春季有效防除麦田茼草的除草剂配方。结果表明,40％肟草酮水分散粒剂60g／667m2＋50％异丙隆可湿性粉剂100g／667m2、7．5％啶磺草胺水分散粒剂11g／667m2＋30g／L甲基二磺隆油悬剂12g／667m2、40％肟草酮水分散粒剂60g／667m2＋30g／L甲基二磺隆油悬剂20g／667m。处理均可用于春季小麦田蔺草的有效防除,且对小麦相对安全。