从不同源杂交种选育玉米二环系的配合力研究

在玉米育种中以GCA,SCA为指标选择玉米二环系的源杂交种作为基础材料来选系,从而选择优良的玉米自交系和杂交组合,本研究结果表明,这种选育玉米自交系的方法是可行和有效的.     

天选系列冬小麦品种抗条锈性分析

天选系列冬小麦品种是陇南麦区最重要的冬小麦品种之一,具有抗条锈性强、丰产性好的特点,为陇南小麦条锈病的持续控制发挥了重要作用。为明确13个天选系列冬小麦品种抗条锈性及其所含抗条锈病基因,选用26个国内外条锈菌单孢菌系对其进行苗期、成株期抗病性鉴定,并结合系谱分析进行了基因推导。结果发现,在苗期,天选44号、天选46号和天选50号的抗性谱与已知基因载体品种洛夫林13基本一致,可能含有Yr9及未知抗条锈病基因;天选43号、天选48号和天选51号的抗性谱与已知基因载体品种Moro一致,可能含有Yr10+Yrmor;天选52号、天选53号和天选55号的抗性谱与Line R55基本一致,可能含有Yr26,其余品种抗性谱与已知基因载体品种不一致,初步推测含有未知抗条锈病基因。天选43号、天选44号、天选46号、天选48号、天选50号、天选51号、天选52号、天选53号和天选55号对条锈菌新菌系G22-9和G22-14表现感病,对其余供试小种(菌系)表现抗病;天选47号和天选49号对CYr33、G22-9和G22-14表现感病;天选45号和天选54号对所有供试小种(菌系)均表现抗病。在甘肃省不同生态区的7个试验点进行成株期抗条锈性评价,发现除天选44号、天选45号和天选54号表现抗病外,其余品种均表现感病。     

小麦雄性不育系AL18A育性恢复基因的QTL定位

为加快AL型杂交小麦的发展,以不育系AL18A、恢复系99AR144-1及二者杂交F2代群体为材料,选用SSR标记和分离群体分组分析法进行育性恢复基因的QTL定位。结果表明,育性恢复由主效和微效基因共同控制,采用复合区间作图法分析,在1B染色体上检测到了1个主效恢复基因QTLqRf-1B-1,在5AL染色体上检测到了1个微效QTLqRf-5A-1。qRf-1B-1位于SSR标记Xbarc8与Xgwm413之间,与两标记的遗传距离分别为0.85cM和2.00cM,LOD值为14.06,加性效应为18.87,可解释22.43%的表型变异;qRf-5A-1位于SSR标记Xgwm595与Xgwm410之间,与两标记的遗传距离分别为10.00cM和0.10cM,LOD值为3.18,加性效应为12.32,可解释5.44%的表型变异。     

陕西省2015-2016年小麦区试品种（系）的抗白粉病分析

为了明确陕西省2015-2016年小麦区试品种(系)的白粉病抗性,以陕西省各地采集的白粉菌混合菌系作菌源,分别在苗期采用人工接种、成株期诱发发病的方法对228份陕西省区试品种(系)和32份已知抗白粉病基因载体品种(系)进行抗性鉴定.结果表明,Pm4a、Pm4b、Pm13、Pm17、Pm18、Pm19、Pm21、Pm24、Pm30、Pm2+6、Pm2+Mld、Pm2+6+?、Pm5+6、Pm“XBD”基因对小麦白粉病表现免疫或高抗;Pm3a、Pm3b、Pm6、Pm4+8、Pm4b+Mli、Pm4+2+?基因对小麦白粉病表现出较弱的抗性,其他基因对供试菌系没有抗病性.228份区试品种(系)中,大多数对白粉病表现为感病,仅有14份在苗期和成株期均表现抗病,33份仅在成株期表现抗病,分别占区试品种(系)总数的6.14％和14.47％.     

Revisiting rice breeding methods – evaluating the use of rapid generation advance (RGA) for routine rice breeding

Rice production needs to increase in the future in order to meet increasing demands. The development of new improved and higher yielding varieties more quickly will be needed to meet this demand. However, most rice breeding programmes in the world have not changed in several decades. In this article, we revisit the evidence in favour of using rapid generation advance (RGA) as a routine breeding method. We describe preliminary activities at the International Rice Research Institute (IRRI) to re-establish RGA on a large scale as the main breeding method for irrigated rice breeding. We also describe experiences from the early adoption at the Bangladesh Rice Research Institute. Evaluation of RGA breeding lines at IRRI for yield, flowering time and plant height indicated transgressive segregation for all traits. Some RGA lines were also higher yielding than the check varieties. The cost advantages of using RGA compared to the pedigree method were also empirically determined by performing an economic analysis. This indicated that RGA is several times more cost effective and advantages will be realized after 1 year even if facilities need to be built. Based on our experience, and previous independent research empirically testing the RGA method in rice, we recommend that this method should be implemented for routine rice breeding in order to improve breeding efficiency.     

棉花陆海染色体片段代换系BC_7F_2群体纤维产量和品质性状表现及相关分析

为了揭示棉花染色体片段代换系BC_7F_2纤维产量性状和品质性状之间的相关关系,筛选纤维品质优异的新材料。以1套陆海染色体片断代换系为材料,对BC7F2高代回交群体的产量性状与纤维品质性状的表性数据进行评价及偏相关分析。结果表明:群体各性状的平均值接近于轮回亲本‘中棉所36’,群体内存在丰富的遗传变异。纤维上半部平均长度超轮回亲本比例为30.25%,断裂比强度超轮回亲本比例为71.25%,衣分超轮回亲本比例为29.38%。总体上单铃重与马克隆值、整齐度指数呈极显著正相关,衣分与上半部平均长度、断裂比强度呈显著负相关,与单铃重呈极显著负相关。从中筛选出部分纤维品质突出的单株,纤维上半部平均长度高于30.00 mm,断裂比强度高于31.00 cN/tex。     

对云南省生态保护红线评估工作的思考

生态保护红线划定是党中央治国理政坚强意志和决心战略,是国土空间规划编制的3条控制线之一,科学评估生态保护红线是落实中央战略意志,实施国土空间管控,促进地方管理事务协调发展的重要举措。文中阐述云南省现有生态保护红线划定情况,分析尚存在着的生态保护红线与现状地类、规划、各类矿业权的交叉冲突以及与自然保护地矛盾冲突等问题,挖掘存在问题的原因,从评估目标、技术准备、评估工作的组织实施以及自然保护地调整、生态保护红线调整、3条控制线重叠的协调等方面对生态保护红线评估工作进行研讨。     

黄淮和长江中下游冬麦区小麦品种(系)农艺性状及其聚类分析

气候变暖对我国乃至世界小麦育种和生产有很大影响。为了研究我国不同生态麦区小麦品种(系)农艺性状适应气候变化调控机理,本研究以黄淮冬麦区北片和南片及长江中下游冬麦区的20个当前大面积推的小麦品种、新审定品种和新选育品系为试验材料,在黄淮冬麦区北片河北省石家庄市种植,在返青期前对其抗旱抗冻性、根冠比和叶片干重与鲜重比进行调查;收获后对株高、穗长、穗下节间长、分蘖数、小穗数、穗粒数、千粒重、单株生物量、单株粒重、经济系数等10个农艺性状进行了考种和相关、聚类和主成分分析。结果表明,不同麦区小麦品种(系)苗期的抗旱抗冻性为黄淮冬麦区北片黄淮冬麦区南片长江中下游冬麦区。三大生态麦区的单株粒重与分蘖数、穗粒数、单株生物量、经济系数均呈极显著正相关,黄淮冬麦区南片和长江中下游冬麦区呈显著和极显著的农艺性状相对较多,说明这两个生态麦区的品种有很大的相似性;但不同生态麦区其他农艺性状正负相关各有一定差异。在欧氏距离20处,20个小麦品种(系)被聚类为长江中下游冬麦区和黄淮冬麦区南片品种(系)(第Ⅰ类)及黄淮冬麦区北片品种(系)(第Ⅱ类)两个大的生态型;在欧氏距离6处,Ⅰ类又分为分别以‘百农207’‘济麦22’和‘西农979’为代表的3个亚类,Ⅱ类是以‘长旱58’为代表。产量、穗长、株高和经济系数4个主成分因子对10个农艺性状表现型变异累计贡献率为76.39%。‘济麦22’等黄淮冬麦区北片的品种(系)综合得分在前20株中占95%。以上研究结果为小麦适应气候变暖育种和引种示范推广提供了重要参考信息。     

Nitrogen fertilization affects yields and storage compound contents in seeds of field-grown soybeans cv Enrei (Glycine max. L) and its super-nodulating mutant En-b0-1 through changing N2 fixation activity of the plants

ABSTRACT

We compared the protein and oil contents, seed yields, and natural abundance of ¹⁵N (σ¹⁵N) of seeds from the plants of the cultivar Enrei, which has moderate nodulating ability (Enrei) with those of its two near-isogenic lines (NILs), a super-nodulating genotype of Enrei, i.e., En-b0-1, and a non-nodulating genotype of Enrei, i.e., En1282. Plants of these three genotypes were grown on four types of field plots with different types of urea coated slow-release nitrogen (N) fertilizers (CUSLNFs) which delivered N in different manners during plant growth . The seed yield of the En1282 plants was similar to that of the Enrei plants but much greater than that of the En-b0-1 plants when the plants were grown on the field to which a CUSLNF with a long lifespan was applied. The amounts of protein per seed were positively correlated with those of oil per seed in the case of En1282 plants irrespective of the field N conditions. The seed protein contents were proportional to the seed weight in both En1282 and Enrei plants. Such a relationship was not observed in the En-b0-1 plants, and the protein and oil contents in the seeds of En-b0-1 plants were negatively correlated with each other. These observations suggested that the N supply to maturing seeds was a key to the protein contents in the En1282 and Enrei plants and that the C supply to maturing seeds was a key to the protein contents in the En-b0-1 plants. The comparison of the σ¹⁵N values, protein contents, and seed yields of seeds from En1282 plants suggested that the Enrei plants assimilated considerable amounts of N from the soil during the late plant growth. We concluded that high N₂ fixation activity depressed the amounts of oil per seed and changed the protein and oil contents in soybean seeds.     

玉米辐射诱变后代M4选系配合力效应分析

以经60Coγ射线处理选育得到的M4代诱变系及其基础材料R08和48-2为被测系,与玉米骨干自交系不完全双列杂交,分析主要农艺经济性状的配合力效应。结果表明:基础材料经辐射诱变后各性状的配合力产生了不同程度的变化;R08的诱变系11和17与48-2的诱变系26和31,其产量性状一般配合力改良效果较好,是高产育种的良好材料,但株高和穗位高GCA偏大;48-2的诱变系23、25、28、29和30虽有利于缩短生育期、降低株高和穗位高,但产量性状GCA表现较差,有待进一步改良;诱变系24产量GCA表现一般,是缩短生育期、降低株高和穗位高的理想材料;其余诱变系各具特点,需在育种实践中有针对性地改良和利用。