含白叶枯病抗性基因Xa23水稻恢复系的分子标记辅助选育

 通过常规杂交育种技术和分子标记辅助选择技术,对携有白叶枯病抗性基因Xa23的亲本材料CBB23进行回交转育和农艺性状改良。通过分子标记辅助选择检测目的基因,快速获得了12份具有Xa23基因的恢复系稳定材料。采用白叶枯病菌株的专化强毒菌系P6对该12份材料进行室内接种鉴定,筛选出1份高抗白叶枯病的抗性新恢复系材料。应用3个不同的不育系对该恢复系进行测交,结果表明该恢复系具有良好的恢复性及产量潜力。     

沙棘定向培育的试验研究

在内蒙古克什克腾旗对引进和选优的沙棘品种进行了13年的区域性试验，筛选出无刺、高V-C型、高氨基酸型、大果等10个有较高经济价值的沙棘优良类型，在筛选的基础上，结合生化测定，在不同立地条件下，定向栽培，推广面积达3000hm^2。     

籽粒苋草粉对生长肥育猪饲养效果试验

为了寻找配合料中籽粒苋草粉的最佳用量，通过不同含量籽粒苋草粉配合料对生长肥猪的饲养对比试验，初步筛选出含有１０％籽粒苋草粉配合料的最佳配方。     

属性识别模型在水利水电规划方案综合优选中的应用

针对目前水利水电规划方案综合优选方法中存在的问题，提出了基于变异系数权重的水利水电规划方案综合优选属性识别模型。该模型采用反映评价指标特征值之间差异性的参数——变异系数作为评价指标的权重，减小了权重确定的主观性，且模型求解方法简单易学。实例分析表明，这一模型和方法是合理、可行的。     

中早熟玉米新杂交种98-ZW-1选育报告

玉米新杂交种98-ZW-1是白银市农业科学研究所以自育自交系98-W-1为母本、自育自交系98-Z-1为父本杂交选育而成.在2002-2003年白银市多点区域试验中,平均折合产量12 032.25 kg/hm2,较对照品种沈单10号增产9.78%;在2002-2004年生产试验中,平均折合产量12 063.54 kg/hm2,较对照品种沈单10号增产3.3%.中早熟,株高246 cm,百粒重40.0 g左右,籽粒含粗蛋白111.0 g/kg、粗脂肪46.2 g/kg、淀粉716.2 g/kg、赖氨酸3.6 g/kg.高抗大斑病和红叶病,适应性强.适宜在白银市高扬程灌区海拔较高的干旱半干旱地区推广种植.     

棉花细胞质雄性不育育性恢复基因的定位及分子标记辅助育种研究进展

棉花细胞质雄性不育系统在实现棉花杂交种子大规模生产和培育高产、优质、抗逆等棉花新品种中具有重要的应用价值,而恢复系的好坏对细胞质雄性不育系杂交种的选育的利用起着举足轻重的作用。因此,培育优良恢复系至关重要。主要介绍了棉花细胞质雄性不育系、恢复系的类型,综述了棉花细胞质雄性不育育性恢复基因的遗传方式和遗传定位研究进展,讨论了恢复基因的精细定位和分子标记鉴定在分子标记辅助育种中的意义和应用前景,并针对目前存在的问题提出相应对策。     

Effects of high- vs. low-yield environments on selection for increased biomass yield in switchgrass

No information is available on the effects of different biomass yield environments on selection efficiency in switchgrass (Panicum virgatum L.) breeding improvement. This study was conducted to assess the effects of high- and low-biomass yield environments (HYE and LYE, respectively) on recurrent selection for general combining ability (RSGCA) in a lowland population of switchgrass (NL-94). The top 14 of 65 NL-94 C₀ parent plants were selected based on biomass yield of half-sib (HS) progeny tested for one post-establishment year under HYE and LYE conditions. Nine of the 14 C₀ parent plants were the same based on HS performance under HYE and LYE. Selected plants were intercrossed to produce NL-94 HYE and NL-94 LYE C₁ populations. One hundred and twenty-five HS C₁ progeny families (60 NL-94 HYE and 65 NL-94 LYE) were evaluated for biomass yield for 3 years (2002–2004) under HYE and LYE conditions. The HYE produced about 2.5 times higher biomass yields than the LYE in both C₀ and C₁ HS progeny tests. Estimated additive genetic variance and predicted gains from selection (ΔG) were high in the C₁ populations indicating that RSGCA should achieve higher biomass yields. Mean biomass yields of C₁ HS families originating from the LYE protocol were significantly higher than those of families originating from the HYE protocol in both HYE and LYE performance tests, suggesting greater selection response under LYE in the C₀ population. The estimates of narrow-sense heritability ( ) and ΔG from the C₁ populations indicate that positive response to selection for biomass yield is possible in subsequent cycles of selection under either HYE or LYE, with a possible small advantage for HYE.     

Evaluation of Early Generation Testing in Chickpea1)

Inter-generation correlations between F₂-F₃, F₂-F₄ and F₃-F₄ in six crosses of chickpea were calculated by using individual plant/progeny means. In general, correlation values in case of plant height, seeds per pod and 100-seed weight were higher between F₃ and F₄ than those between F₂ and F₃ and F₂ and F₄. However, inter-generation correlations were mostly non-significant in case of pods per plant and grain yield. These results clearly show that selection in F₃ can be fruitful for seeds per pod and 100-seed weight. However, selection for pods per plant and grain yield in early generations may not show any relationship with later generation performance for these traits.     

Identification and marker‐assisted introgression of QTL conferring resistance to bacterial leaf blight in cowpea (Vigna unguiculata (L.) Walp.)

Bacterial leaf blight (BLB), caused by Xanthomonas axonopodis pv. vignicola (Xav), is widespread in major cowpea [Vigna unguiculata (L.) Walp.] growing regions of the world. Considering the resource poor nature of cowpea farmers, development and introduction of cultivars resistant to the disease is the best option. Identification of DNA markers and marker‐assisted selection will increase precision of breeding for resistance to diseases like bacterial leaf blight. Hence, an attempt was made to detect QTL for resistance to BLB using 194 F_2 : 3 progeny derived from the cross ‘C‐152’ (susceptible parent) × ‘V‐16’ (resistant parent). These progeny were screened for resistance to bacterial blight by the leaf inoculation method. Platykurtic distribution of per cent disease index scores indicated quantitative inheritance of resistance to bacterial leaf blight. A genetic map with 96 markers (79 SSR and 17 CISP) constructed from the 194 F₂ individuals was used to perform QTL analysis. Out of three major QTL identified, one was on LG 8 (qtlblb‐1) and two on LG 11 (qtlblb‐2 and qtlblb‐3). The PCR product generated by the primer VuMt337 encoded for RIN2‐like mRNA that positively regulate RPM1‐ and RPS2‐dependent hypersensitive response. The QTL qtlblb‐1 explained 30.58% phenotypic variation followed by qtlblb‐2 and qtlblb‐3 with 10.77% and 10.63%, respectively. The major QTL region on LG 8 was introgressed from cultivar V‐16 into the bacterial leaf blight susceptible variety C‐152 through marker‐assisted backcrossing (MABC).