小麦新型不育类型利用潜力分析

K、L、Sh、T、A型 5类小麦杂种 F1研究表明 :1 K、L、Sh、T4类细胞质对杂种 F1不育的恢复度和单株产量均存在不同程度的不良效应 ;2不育系易恢复性能为 K>L≥ Sh>T型 ;3 K型不育系恢复度高的一个重要原因在于小穗中部小花结实性好 ;4研究 K、L、Sh型恢复度时 ,利用国际法表示恢复度较为合理 ;5F1单株籽粒产量普遍存在优势 ,平均超双亲杂种优势为 8.57% ,具有 1 5%以上的杂种组合占总组合 2 3.33%。单株籽粒产量优势为 A>K>Sh>L>T;6产量构成因素超双亲优势为千粒重 >单株穗数 >单穗粒数 ,其中千粒重优势为 K、L、Sh≥ A>T,单穗粒数优势为 A>K>L>Sh>T,单株穗数优势为 A>L>K>Sh>T;7K、L、Sh比 T型细胞质不育类型具有更大利用潜力。     

杂交粳稻及其亲本千粒重与产量、品质的相关性

为了探明杂交粳稻及其亲本千粒重与产量、品质的关系,以4个千粒重介于23.1~28.0 g之间的BT型不育系和24个千粒重介于18.1~32.0 g之间的三系粳稻恢复系,采用p×q不完全双列杂交(NCⅡ)设计,配制96个杂交组合为试验材料,对F1千粒重优势表现、F1千粒重与亲本千粒重及其与产量、品质性状间的相关性进行分析,确定高产优质兼顾的杂交粳稻的千粒重范围。结果表明:(1)56.3%的杂交组合千粒重超过其双亲平均值,19.8%的杂交组合千粒重表现正向超亲优势;(2)F1千粒重与母本千粒重、父本千粒重、双亲千粒重平均值的相关性均达极显著水平(r=0.33**、0.71**、0.78**),且恢复系千粒重对杂种的影响大于不育系;(3)F1千粒重、父本千粒重及双亲千粒重平均值与组合单株产量的相关性均达极显著水平(r=0.55**、0.47**、0.51**),母本千粒重与组合单株产量相关不显著;(4)F1千粒重、父本千粒重与糙米率、精米率、整精米率、垩白粒率、粒长、粒宽均呈极显著正相关,与透明度呈显著正相关,母本千粒重与垩白粒率、垩白度、粒长均呈极显著正相关,与粒宽呈显著正相关;(5)杂交粳稻育种中具有高产优质兼顾的F1千粒重范围应在25.1~27.0 g之间。     

大豆产量的形成和光合作用

大豆籽粒富含蛋白质（40％）和脂肪（20％），而碳水化合物含量少，是一种贮藏能量较高的作物。另外，作为豆科作物的一种，它的根瘤能固定空气中的游离氮，把生成的氮化物的绝大部分供给大豆植株。这个过程同时也消耗大豆体内的光合产物，使大豆产量形成过程中更加依靠光合作用。1．大豆产量的形成大豆产量一般分为生物产量和经济产量。生物产量指全生育期间大豆植株单位面积上形成的干物质产量，而经济产量指单位面积上主产品（大豆为籽粒）的产量。经济产量与生物产量的比值即为经济系数，也称收获指数。大豆的经济系数一般只有0．3～0．…     

小麦杂种及其亲本苗期叶片家族基因差异表达及其与杂种优势关系的初步研究

为探讨小麦杂种优势形成的分子机理,以一套双列杂交组合的苗期叶片为材料,利用mRNA差异显示技术分析了杂种及其亲本间MADS－box、G－ box、Ser/Thr蛋白激酶、EIF－4A、ARF1基因家族共5类家族基因在杂交种和亲本之间的表达差异。并与杂种性状表现和杂种优势进行了相关分析。结果发现,除ARF1家族基因外,其余家族基因在杂种和亲本间存在显著的表达差异,差异表达类型可概括为4种：（1）双亲共沉默;（20单亲表达沉默;（3）杂种特异表达;（4）单亲表达一致。分析发现,MADS－box、G－box和EIF－4A家族基因在杂种和亲本间的差异表达模式相似,均以单亲特异表达和种特异表达类型所占比例最高。相关分析结果表明,以上所有家族基因的总体差异表达程度与所有性状的杂种表现均不相关,MADS－box家族基因中杂种特异表达类型与小穗数、单株产量和单穗产量杂种优势呈显著正相关,双亲共沉默类型与小穗数、千粒重和单穗产量杂种优势呈显著负相关,另外,EIF－4A家族基因中单亲表达一致型与单穗产量杂种优势呈显著正相,但双亲共沉默类型与小穗数和单穗产量杂种优势呈显著负相关,对于G－box基因家族而言,仅小穗数杂种优势和双亲共沉默类型成显著负相关,而蛋白激酶家族基因的各种差异类型与性状杂种优势的相关分析均不显著。这些研究表明,调控基因的差异表达与杂种优势形成有密切关系。     

六个黄淮麦区优质小麦品种在晋中麦区晚播的产量与品质性状研究

目的：为拓宽山西优质小麦品种资源,采用田间试验,研究来自黄淮麦区的6个优质小麦品种在晋中晚熟冬麦区的籽粒产量及品质性状表现。方法：供试小麦品种分别是：来自河南省国家小麦工程中心的豫农416（编号Y-1）、豫麦34（Y-2）、豫麦70（Y-3）和豫麦18（Y-4）,来自山西省农科院棉花科学研究所的舜麦紫秆（S-1）和舜麦1718D（S-2）,以山西农业大学育成品种山农129为对照（CK）。试验于2010年10月15日在山西农业大学实验农场进行,收获后测定籽粒产量与产量结构及籽粒品质。结果：引进的6个黄淮麦区育成小麦品种在晋中晚熟冬麦区晚播种植,其籽粒品质均优于当地品种山农129,但产量不足。6个引进品种在晋中晚播种植后,其籽粒蛋白质含量、湿面筋含量等相关的籽粒品质亦明显高于原品种。相对而言,豫麦34、豫农416和舜麦紫秆均为高蛋白（〉17％）强筋（≥32％）品种,但前者高产（〉5800kg·hm-2）,后两者中产（〉4300kg·hm-2）;豫麦70和舜麦1718D均为高蛋白中筋（30％-32％）品种,但前者中产,后者低产（〈4000kg·hm-2）;豫麦18则为中等蛋白（〉16％）中筋的高产品种,当地品种山农129为低蛋白（〈16％）低湿面筋（〈30％）的高产品种。结论：豫麦34和豫麦18对改良山西小麦品种籽粒品质具有一定的意义。     

几类异质易恢复小麦雄性不育系杂种籽粒品质研究初报

利用具有粘果出羊草（Ae.kotschyi),易变山羊草（Ae.variabilis),偏凸山羊草（Ae.ventricosa)和二角山羊草（Ae.bicornis)异源细胞质小麦雄性不育系（以下简称粘,易,偏和二角型）组配成不同组合的杂种小麦,研究这4种不育系对杂种小麦籽粒品质的影响。结果表明,由它们所配制的杂种小麦在蛋白质含量,湿面筋含量,沉淀值等性状上均高于具有普通小麦细胞质的相同核型杂种小麦,尤其粘,易型某些组合在湿面筋含量,沉淀值两性状上差异达到显著水平。因此,利用这4种不育系很有希望培育出优势,高产的杂种小麦。     

硬粒小麦、提莫菲维小麦与四倍体长穗偃麦草属间杂种的形态和细胞遗传学研究

首次获得硬粒小麦（Triticum durum Desf),提莫菲维小麦（T.timopheevi Zhuk)与四倍体长穗偃麦草（tetraploid Elytrigia elongata)的属间杂种,杂交当代结实率分别为5．29％和1．41％,杂种均表现为多年生,具很强的生活力,形态上呈双亲中间类型,杂种F1自交不育,用普通小麦,硬粒小麦回交,以硬粒小麦为母本的F1均获得交种子,杂种F1花粉母细胞减数分裂中期I染色体配以构型分别为：13．78I＋6．87II＋0．147III,9．10I＋9．11 II＋0．20III,F1形成的二价体主要是四倍体长穗偃麦草染色体之间配对所致,并推测四倍体长穗偃麦草具促进小麦部分同源染色体配对或抑制小麦ph基因作用的特殊遗传系统。     

通过“供体—受体”原生质体融合将裸燕麦部分核基因组转移给普通小麦

本文进行了小麦和裸燕麦悬浮细胞原生质体的电融合,并基于双亲失活（用ＩＯＡ处理受全小麦原生质体,用γ－射线照射供体裸燕细胞系）,获得可能的杂种愈伤组织。对７块愈伤组织进行了乙醇脱氢酶（Ａｄｈ）同工酶筛选,发现５块表现出双亲特征酶带。对３个杂种细胞系进行５种同工酶分析,证实它们均为稳定的不对称体细胞核杂种细胞系;它们表现出小麦的完整谱带和裸燕麦的部分谱带。对２个杂种细胞系及亲本的核糖体ＤＮＡ Ｓｏｕｔ     

环境对杂交水稻胞质及核质互作遗传表现的影响．不同N素下不育胞质对杂种一代光合生理与保护酶活性的影响

研究结果表明,水稻不育胞质对杂种一代产量表现的影响与其对后期干物质生产与分配的影响密切相关在４种Ｎ素条件（６０、１５０、２４０和３３０ｋｇＮ·ｈｍ－２）下,不育胞质对杂种一代前期干物质生产与累积呈不同程度的正效应,其平均效应值为１．３７～１．４７ｇ·ｍ－２·ｄ－１进入生育后期,不同Ｎ处理的胞质效应表现明显不同,在Ｎ２（１５０ｋｇＮ·ｈｍ－２）或Ｎ３（２４０ｋｇＮ·ｈｍ－２）下,不育胞质对杂种一代的干物质生产及产量表现正效应不显著,因而产量较高;但在Ｎ素胁迫下（６０ｋｇＮ·ｈｍ－２或３３０ｋｇＮ·ｈｍ－２）,其胞质效应多呈显著负效应,因而减产．分析表明,逆境下水稻不育胞质对杂种一代干物质生产与分配的影响呈显著负效应,而使产量降低,与逆境下不育胞质对杂种一代后期叶片ＲＵＢＰｃａｓｅ、ＡＴＰａｓｅ和保护酶活性呈显著负效应有关,对在Ｎ素胁迫下水稻多胺代谢、保护酶活性和自由基含量变化及其生理联系进行了讨论     

F_1不育株对油菜杂交种产量影响程度的分析与预测

分析了１９９３—１９９５年油菜区域试验中Ｆ１不育株对产量的影响及不育度不同的不育株对产量的影响程度。结果表明：Ｆ１不育株（包括全不育、半不育株）率与杂种产量间存在显著负相关关系;Ｆ１不育株对产量的影响主要来自半不育株。不同生产年份Ｆ１不育株造成的产量降幅趋于一致;不育株率低于１３．５％,不足以对产量造成显著（≥１０％）影响。     

外源6-BA对不同时期遮光下江汉平原稻茬小麦产量的影响

针对江汉平原小麦生长季阴雨天气持续时间长、光照辐射少而形成的弱光环境,本试验以江汉平原大面积推广品种‘郑麦9023’和‘扬麦23’为材料,研究了孕穗期遮光处理(S₁)和开花期遮光处理(S₂)对两品种小麦产量的影响及其生理基础,并设置遮光前喷施6-BA处理(S₁+6-BA、S₂+6-BA),探究喷施6-BA对弱光胁迫的缓解作用.结果表明:孕穗期与开花期遮去自然光强的45%均显著降低了各处理籽粒产量,且开花期遮光处理籽粒产量下降幅度大于孕穗期遮光处理,遮光处理开花后14~21 d籽粒干物质积累量显著下降导致的粒重降低是造成籽粒产量下降的主要原因;两时期遮光均降低了成熟期干物质积累量,改变了营养器官干物质分配比例,使籽粒产量更多地依赖于开花前营养器官贮藏同化物,从而导致遮光处理籽粒产量下降.开花期遮光前喷施6-BA处理的籽粒产量显著大于开花期遮光处理,主要是由于喷施6-BA能够延缓遮光处理下旗叶的衰老进程,其灌浆速率和粒重亦显著大于遮光处理,同时提高了开花期遮光处理植株在成熟期的干物质积累量,且S₂+6-BA花后同化物的转运量及对籽粒的贡献量较S₂增大,最终提高了遮光处理的籽粒产量.总之,开花期遮光对小麦籽粒产量的影响大于孕穗期,开花期遮光前喷施外源6-BA对遮光造成的不利影响有一定的缓解效应,降低了开花期遮光造成的产量损失.     

Physiological Factors Limiting Grain Size in Wheat

The effects on grain size of changing the supply of assimilates,by thinning before anthesis or by shading the plants or by halvingthe ears either early or late in grain growth, were studiedin two glasshouse experiments with Kleiber spring wheat (Triticumaestivum L.), in 1976 and 1977. Late treatments had no effect,presumably because little grain growth occurred thereafter.Thinning the plants before anthesis increased, and shading theplants soon after anthesis decreased grain size. Halving theears soon after anthesis increased the size of the remaininggrains, but grain weight per ear decreased. The effect on grainsize of halving the ear tended to be smaller under conditionsmore favourable for photosynthesis, except when the plants werethinned before anthesis. Shading decreased the total amountof nitrogen per culm and the proportion of total nitrogen recoveredin the ear. Halving increased the retention of nitrogen in thestem of unshaded shoots and had no effect on nitrogen distributionwithin shaded shoots. In 1977 halving the ear increased the rate of dry matter accumulationin the grain throughout the grain filling period, but in 1976the increase in dry weight was faster in the grains of halvedears only during early grain growth. Later the grains in halvedand intact ears increased in dry weight at the same rate, eventhough the supply of photosynthate and the capacity of the grains(as measured by volume) were greater in the halved ears. Theseresults are discussed in relation to the influence on finalgrain weight of assimilate supply and the storage capacity ofthe grain.     

夏闲期耕作对旱地小麦土壤水分及植株氮素吸收、运转特性的影响

采用大田试验,研究了夏闲期耕作对旱地小麦播种前和各生育期0～300 cm土壤水分、植株氮素吸收和运转特性的影响.结果表明: 夏闲期耕作可提高播种前和各生育期0～300 cm土壤蓄水量,且枯水年效果较好.夏闲期耕作可显著提高各生育期植株氮素积累量、开花期叶片和茎秆+茎鞘氮素积累量、成熟期籽粒氮素积累量,显著提高茎秆+茎鞘氮素运转量及其对籽粒的贡献率、叶片氮素运转量、花前氮素运转量、花后氮素积累量,最终提高氮素吸收效率,以前茬小麦收获后45 d深翻效果较好.夏闲期耕作条件下,土壤水分与花前氮素运转量及籽粒氮素积累量显著相关,且枯水年关系更密切;播种至开花期土壤水分与花后氮素积累量在丰水年显著相关,而枯水年无显著相关关系.夏闲期耕作,尤其是雨后深翻有利于蓄水保墒及植株氮素吸收和转运.     

根修剪对黄土旱塬冬小麦(Triticum aestivum)根系分布、根系效率及产量形成的影响

通过田间试验研究了不同时期根修剪处理对冬小麦（Triticum aestivum）根系大小与分布、根系效率、水分利用效率及产量形成的影响。设置4个根修剪处理：越冬期小剪根（WS）、越冬期大剪根（WB）,返青期小剪根（GS）、返青期大剪根（GB）,未剪根小麦作为对照（CK）。结果表明,到花期时,各根修剪处理小麦的在0～120cm总根量均显著小于对照。与对照相比各根修剪处理主要是显著地减少了上层土壤中的根量。但WS和GS两小剪根处理和对照相比在中层土壤中有较大的根量;花后各处理小麦旗叶的气孔导度和蒸腾速率均显著大于对照。这说明根修剪处理减少了小麦表层的根量,从而削弱了表土干旱信号对作物与外界气体交换的抑制作用。花期时各根修剪小麦的净光合速率均显著高于对照,而单位面积上的根呼吸速率均显著小于对照,根修剪处理提高了小麦的根系效率,使更多的光合产物用于籽粒生产,从而提高了小麦的收获指数。根修剪还提高了小麦的水分利用效率,其中WS、WB、GS处理的水分利用效率显著高于对照。但是GB处理的水分利用效率却没有显著提高。因此,本研究进一步证明了由不同年代品种得到的推测,认为在旱地农业中,通过遗传育种或采用适当农艺措施优化根系分布,既可以减少生长前期作物对水分的过度消耗,又能够削弱花后表土过度干旱对作物生长抑制作用,同时降低根系对同化产物的消耗,对作物产量及水分利用效率的提高具有积极的作用。     

Heterosis of biomass production in Arabidopsis. Establishment during early development

Heterosis has been widely used in agriculture to increase yield and to broaden adaptability of hybrid varieties and is applied to an increasing number of crop species. We performed a systematic survey of the extent and degree of heterosis for dry biomass in 63 Arabidopsis accessions crossed to three reference lines (Col-0, C24, and Nd). We detected a high heritability (69%) for biomass production in Arabidopsis. Among the 169 crosses analyzed, 29 exhibited significant mid-parent-heterosis for shoot biomass. Furthermore, we analyzed two divergent accessions, C24 and Col-0, the F(1) hybrids of which were shown to exhibit hybrid vigor, in more detail. In the combination Col-0/C24, heterosis for biomass was enhanced at higher light intensities; we found 51% to 66% mid-parent-heterosis at low and intermediate light intensities (60 and 120 micromol m(-2) s(-1)), and 161% at high light intensity (240 micromol m(-2) s(-1)). While at the low and intermediate light intensities relative growth rates of the hybrids were higher only in the early developmental phase (0-15 d after sowing [DAS]), at high light intensity the hybrids showed increased relative growth rates over the entire vegetative phase (until 25 DAS). An important finding was the early onset of heterosis for biomass; in the cross Col-0/C24, differences between parental and hybrid lines in leaf size and dry shoot mass could be detected as early as 10 DAS. The widespread occurrence of heterosis in the model plant Arabidopsis opens the possibility to investigate the genetic basis of this phenomenon using the tools of genetical genomics.     

玉米雄性不育系及其同型可育系根系的时空变化

采用土柱栽培试验,比较了玉米细胞质雄性不育系（CMS）及其同型可育系根系特性的差异.结果表明：CMS的地上部分物质积累能力较强,其籽粒产量显著高于可育系（P<0.05）;其根系干质量相对较高,根冠比变化趋势与根系干质量类似.CMS在0～20 cm和20～40 cm土层平均根量高于其可育系,在40～80 cm土层优势更为明显.CMS在0～20 cm和20～40 cm土层的平均根系活力显著高于其可育系（P<0.05）;0～20 cm和20～40 cm土层根系的SOD活性和可溶性蛋白含量与可育系差异不显著, 40～80 cm土层显著高于其可育系（P<0.05）;在生育后期,CMS的根系活力、SOD活性和可溶性蛋白含量优势更明显.表明玉米不育植株具有深层根量多、生育后期根系活性高的特点,从而使其根系功能期延长,植株衰老进程减缓.这可能是雄性不育玉米增产的重要原因之一.     

Gibberellins and heterosis in maize : I. Endogenous gibberellin-like substances

Under controlled environment and/or field conditions, vegetative growth (height, internode length, leaf area, shoot dry weight, grain yield) was greater in an F₁ maize hybrid than in either parental inbred. Endogenous gibberellin (GA)-like substances in apical meristem cylinders were also higher in the hybrid than in either inbred, both on a per plant and per gram dry weight basis. There were no apparent qualitative differences in GA-like substances, however. Levels of GA-like substances in all genotypes were highest prior to tassel initiation. Chromatographic comparisons of the GA-like substances and authentic standards of GA native to maize on gradient-eluted SiO₂ partition and reverse-phase C₁₈ high-pressure liquid chromatography columns are described. No consistent differences in abscisic acid levels of the three genotypes were observed. This correlation of heterosis for endogenous GA-like substances with heterosis for growth suggests that amounts of endogenous GA may be related to hybrid vigor in maize.     

Interorgan photosynthate partitioning in alfalfa

The net partitioning of current photosynthate among vegetative organs of nodulated alfalfa (Medicago sativa L.) was investigated by determining radiolabel distribution from upper and lower source leaves, at different times of day, and during successively longer chase periods. Photosynthate was exported sooner and more completely by a fully expanded lower than by a fully expanded upper source leaf. The radiolabel pulse from the lower source leaf peaked in the main stem within 1.5 hours, in the crown and nodules after 3 hours, in the unexpanded leaves and apex of the main stem after 6 hours, and in the shoots growing from leaf axils on the main stem after 24 hours. The results suggest that the crown, apex, axillary shoots, and nodules both imported and mobilized photosynthate originating at a lower source leaf, while roots and shoots growing from the crown showed net accumulation. The pulse from the upper source leaf was initially rapidly exported by the main stem and imported by the root between 1.5 and 3 hours, but there was no net change of label content of these organs during the ensuing 21 hours. Rapidly growing organs had the highest concentrations, and the largest organs had the highest content of radiolabel. These results provide new information about the accumulation and circulation of photosynthate within the alfalfa plant.     

Availability of reduced N and carbohydrates for ear development of maize

Changes in dry weights, reduced N, nitrate, and nitrate reductase activity of various plant parts of the above ground vegetation (stover) and ears of field grown maize were measured at intervals between anthesis and grain maturity. Nonstructural carbohydrate contents were also measured in some instances. Changes in dry weight and reduced N content were used to approximate net in situ photosynthetic and nitrate assimilation activities and to determine whether the availability of photosynthate or reduced N was limiting grain production.     

遮光对小麦植株氮素转运及品质的影响

以耐弱光性不同的冬小麦品种扬麦158(耐弱光品种)和扬麦11(不耐弱光品种)为材料,研究了拔节至成熟期遮光对小麦籽粒产量、植株氮素代谢及籽粒和面团品质的影响.结果表明:拔节至成熟期遮光22%和33%时,扬麦158和扬麦11籽粒产量分别比对照下降4.1%～9.9%和15.3%～25.8%;而小麦籽粒蛋白质产量分别下降3.0%～8.3%和10.4%～14.1%,且随着遮光程度的加重,小麦籽粒氮素积累对花后氮素积累的依赖性增强.遮光条件下各营养器官中花前贮存氮素转运量均下降,但叶片氮素转运效率(RENP)上升,从而补偿了茎鞘、穗壳中RENP的下降,因此营养器官总RENP未受遮光条件的显著影响.拔节至成熟期遮光提高了小麦籽粒蛋白质含量,这与弱光下籽粒蛋白质积累量下降幅度小于产量下降幅度所形成的"浓缩效应"有关.弱光对成熟期小麦籽粒清蛋白和球蛋白含量无显著影响,但显著提高了醇溶蛋白和麦谷蛋白含量,导致小麦湿面筋含量、面团形成时间和稳定时间提高,面团弱化度降低.