高Liang体细胞无性系后代变异与遗传

对９个高Ｌｉａｎｇ品系的体细胞无性系后代的变异及其遗传稳定性进行了观察。结果表明：Ｒ１再生植株常出现较大变异，但有许多变异不能遗传给后代。Ｒ２的变异频率虽然较低，但大部分变异能遗传下来，并且在Ｒ３即可表现稳定。另外，还观察到许多性状能发生可遗传的变异，但不同性状的变异频率不相同。有些植株的变异只表现在个别性状上，但也有些植株可同时出现几个性状发生变异。     

离子注入诱发棉花过氧化物酶同功酶及农艺性状变异的研究

本文分析了氮离子注入处理棉花种子诱发Ｍ１植株第二真叶过氧化物酶同功酶（ＩＰＯ）变异的遗传表现；Ｍ＝ＩＰＯ和农艺性状变异的频率及类型，探讨了剂量效应及ＩＰＯ变异与农艺性状变异的关系。结果表明：Ｍ１ＩＰＯ变异有些是非遗传的，Ｍ２中ＩＰＯ不同酶带对氨离子注入的敏感性及最佳诱变剂量不同；氮离子注入能诱发较高频率的ＩＰＯ变异及数量性状和多个性状的同时变异，可在较轻的Ｍ１损伤下获得较高的Ｍ２农艺性状变异频率，Ｍ２ＩＰＯ和农艺性状变异频率与Ｍ１ＩＰＯ变异频率的关系可用Ｙ＝Ａ＋ＢＸ＋ＣＸ２来描述。在Ｍ２铃数和早熟性变异株中均可观察到第二真叶ＩＰＯ第８条酶带，而铃重和株高变异株中可观察到第６条酶带。     

裸燕麦体细胞无性系的农艺性状变异

５６个１０－１品系（来源于１１个Ｒ０植株）和２１２个晋燕８号品系（来源于４５个Ｒ０植株）被评价。结果表明，组织培养能够获得有益的农艺性状。８２％的２０－１系谱和９３％的晋燕８号系谱在７个测定性状中至少有一个性状发生显著变异。对每个性状都有一些增加和降低的品系被发现，而且有益的农艺性状变化比不良的变化频率高。再生植物株后代扣进行证明：性状变异是可以遗传的，单株选择能够在作物改良中应用。获得的变异也证     

大麦DNA导入小麦引起叶耳颜色变异的遗传学初步观察

将二棱大麦（叶舌、叶耳红色）ＤＮＡ通过花粉管途径导入小麦品种“百农３２１７”（叶舌、叶耳无色），获得叶耳、叶舌颜色红色的变异植株。观察其后代（Ｔ２、Ｔ３＊），以及“百农３２１７×叶耳红色Ｔ４株”杂交的Ｆ２。结果表明，变异植株的叶舌、叶耳红色性状表现单基因显性遗传，同时也发现，普通小麦叶舌、叶耳红色性状遗传非一对基因控制（导入处理产生的红色∶无色＝３∶１是叶舌叶耳遗传的一个特例），颜色深浅还有数量基因的累加效应，并且一定环境条件（稀植、低温）可诱导叶舌、叶耳红色表现。     

花粉管通道法获得棉花转基因株系主要农艺性状变异分析

通过对花粉管通道法获得的38个棉花转基因株系稳定后代T5代主要农艺性状的变异进行分析发现,外源基因的导入可引起受体植株后代农艺性状可遗传的非靶标变异,且变异广泛,多个农艺性状出现了显著性变异.叶长和叶宽均有变短的趋势,但裂叶缺刻深浅变异方向不定,说明部分叶片变得更加皱缩.株高变异方向不定.与对照相比,吐絮期提前,单株结铃数增加,使皮棉和子棉产量均增加.纤维品质变异也很大,如比强度增大、麦克隆值变大、纤维长度也显著增加;短纤维指数变异方向不定.     

冬小麦品种兰天17号航天诱变后代农艺性状变异分析

为研究小麦空间诱变后代农艺性状的变异规律,用系谱法对冬小麦品种兰天17号SP 1株群、SP 2系群以及SP 2显著突变系和疑似突变系后代的表现进行了研究。结果它在SP1出现了2个显著的株高突变体D16和D38,其中D38在SP 2表现株高和主穗长度的分离,D 16在SP 2的株高与原品种对照差异不显著,但它在SP 3出现了株高和穗长的显著变异。SP 2疑似突变系D 69在SP 3出现了籽粒形态的显著突变。经单株选择,D 38的部分后代在SP 3或SP 4性状就已基本稳定。表明航天诱变小麦种子,可引起后代株高、穗长、穗形、籽粒形态等性状的变异;突变体可能出现在SP 1,也可能出现在SP 2或以后世代;这些突变体经过2～3个世代的单株选择,部分后代的性状就能基本稳定,小麦航天诱变后代农艺性状的变异符合诱变育种的基本规律。     

棉铃疫病菌的生物学特性及其遗传研究

在实验室条件下，对安徽省棉铃疫病菌（Phytophthora boehmeriae Sawada）的若干生物学特性及其遗传进行了研究。结果表明，采自不同地区的棉铃疫病菌生长速率和对棉苗的致病力间均存在极显著差异，甚至采自同一地区的不同菌株间上述性状亦存在显著差异。同时，XC-6生长速率、对棉苗的致病力、菌落形态及同宗配合遗传和变异特性研究表明，其生长速率和对棉苗的致病力性状在单游动孢子后代和自交后代均不能稳定遗传，但菌落形态和同宗配合特性在单游动孢子后代和自交后代均能稳定遗传，提示上述性状在单游动孢子后代和自交后代的遗传和变异特性可能与菌株长期自交和种内杂交有关。     

小黑麦DNA导入普通小麦引起变异及后代选育

应用外源DNA直接导入生物技术，将不同种属的小黑麦总DNA导入普通小麦。可引起性状变异，部分变异可稳定传递给后代，选出的新品系植株性状发生明显变化，产量经济性状比原品种有明显改善，说明将小麦近缘植物的DNA导入普通小麦的方法可创造出新种质。     

转基因抗虫水稻后代农艺性状变异的比较研究

采用群体分离法（Bulk sergeant analysis,BSA）和比较分析方法,以转基因水稻高代材料与非转基因水稻杂交得到的3个F2群体和1个DH群体为材料,分析遗传背景与外源基因对转基因水稻后代农艺性状变异的影响。结果发现,父本的遗传背景对农艺性状表现存在一定的影响;在消除环境因素影响的条件下,F2群体中外源基因对农艺性状变异起到重要作用,并促使农艺性状的分离程度增加。而DH群体中尽管外源基因促进株系变异系数增加,但对主要农艺性状变异的作用不显著。说明组织培养是产生农艺性状变异的主要原因,而外源基因的导入增加了农艺性状变异发生的机会。     

离心超重力诱发水稻变异效应初报

为了研究离心超重力是否对水稻产生诱变作用,通过采用9个不同的离心超重力和处理时间组合处理水稻品种矮秀占的萌动种子,并对处理后代进行研究。结果表明,随着处理的离心超重力加大和处理时间延长,发芽率下降,M2代的变异频率上升。处理效果以超重力为12000×g,处理时间60 min最好。处理M1代未发现明显的表型变异,M2代发生多样性变异,主要表现在茎秆、叶片、生育期、穗部性状、籽粒、稻米外观和直链淀粉含量,并可以稳定遗传。说明离心超重力不仅对水稻处理当代植株的生长发育产生抑制作用,而且可以诱发水稻产生明显的可遗传变异,可以作为一种新的诱变育种手段。     

抗纹枯病、根腐病的转SN1基因小麦的获得与鉴定

SN1是源于马铃薯的一种抗菌肽, 可以抑制多种植物病原菌的生长。小麦纹枯病(主要病原菌为禾谷丝核菌Rhizoctonia cerealis)和根腐病(主要病原菌为平脐蠕孢菌Bipolaris sorokiniana)是小麦的主要土传真菌病害。本研究利用基因工程技术构建了SN1基因的单子叶植物表达载体pA25-SN1, 它受玉米泛素(ubiquitin)启动子的控制;采用基因枪法将pA25-SN1转化小麦推广品种扬麦18幼胚愈伤组织4 000块, 获得203株再生植株, 通过PCR检测出阳性植株55株, 转化率为1.38%。对转SN1基因小麦T₀~T₂代植株, 进行外源基因的PCR、Southern blot、RT-PCR、荧光定量RT-PCR(Q-RT-PCR)分析和小麦纹枯病菌与根腐病菌接种及其抗病性鉴定。结果表明, 转入的SN1基因已经整合到转基因小麦的基因组中, 能够在转基因小麦中遗传、转录与表达。SN1基因的表达提高了转基因植株对小麦纹枯病和根腐病的抗性, 其抗病性可以遗传。     

冬小麦花药愈伤组织无性系株高遗传研究

从Ｈ１花药单倍体试管苗基部，取尚未分化绿苗的胚性愈伤组织建立的体细胞无性系，获得４丛Ｒ１结实株系。从田间Ｒ２的观察中发现，Ｒ１的４株后代中有１株４个穗繁衍的８６个单株发生了变异，Ｒ２的株系变异率为２５％。经过这株变异的Ｒ２、Ｒ３的株高连续观察发现：株高变异范围均很大，并有超亲现象，Ｒ２的变异大于Ｒ３；穗系间和穗系内的变异均极显著，穗系间变异大于穗系内变异；Ｒ３有８．１４％的株系已稳定；Ｒ２和Ｒ３的     

Inter- and intraspecific sequence variations of the chloroplast genome in wild and cultivated Raphanus

To assess the differentiation of the chloroplast genome in wild and cultivated species of Raphanus , nucleotide sequence polymorphisms were investigated for approximately 2 kbp ranging from trnL (UAA) to psbG in R. raphanistrum and R. sativus . Eighteen plants of wild species, 10 Japanese wild radish plants ( R. sativus ), and 31 cultivated plants were used for sequence analysis. Intraspecific variations of the chloroplast genome were present both in wild and cultivated Raphanus . All three genes investigated ( trnL , trnF and ndhJ ) contained nucleotide substitutions within the genus. Whereas, larger numbers of mutations were observed in the intergenic regions. Using the detected variations, the 59 radish plants were classified into 11 haplotypes, seven of which were unique to wild species. Among the haplotypes, one type corresponded completely with the Ogura male sterile cytoplasm. All the cultivated radishes belonged to one of four types, of which three were also observed in Japanese wild radish. The haplotypes were classified into four groups by cluster analysis, and the distribution in the dendrogram confirmed that cultivated radish has multiple origins. On the other hand, the seven haplotypes uniquely observed in R. raphanistrum were considered as useful materials to provide genetic diversity of cytoplasm for breeding of cultivated radishes.     

去早果枝对转基因抗虫棉生长发育与衰老进程的调控效应

 以转基因抗虫棉品种为材料,设置了2个播期和4种去早果枝方式（去基部1个、2个、3个果枝及不去果枝的对照）处理,研究去除早期果枝对棉花生长发育及衰老进程的影响。2年结果表明,去早果枝推迟了棉花的生育进程;去掉1个早果枝处理总果枝数与对照无差异,但去掉2个、3个果枝后明显低于对照,总果节数差异不显著;去早果枝显著提高了第1播期棉花叶面积指数和干物质积累量,去1个、2个和3个果枝处理的干物质积累量在2年中平均比对照高13.5%,17.5%,19.0%,但在第2播期差异不明显;去早果枝降低了第1播期棉花脱落率和烂铃率并提高了棉花的子棉产量,脱落率在2年中平均比对照降低4.5,5.8和9.0百分点,烂铃率平均降低2.2,4.5,4.8百分点;去1个和2个果枝处理的子棉产量在2年的第1播期中比对照平均高9.6%和8.1%,但在第2播期增产不明显,甚至减产。     

小麦体细胞组织离体诱变效应研究

小麦种子经30kRγ射线照射后,再从M1株取未成熟胚培养,用再生株当代(M2R1)的死苗率、不育株率、结实率及株高变化所反映的损伤程度与对照株（R1）比较，无明显差异；M3R2代的变异率也与对照R2相仿。5天龄幼胚用0.5kR照射处理后的再生株M1R1的损伤程度与对照相仿；M2R2的变异率随不同基因型而有增减，但变异率仍有显著提高。未     

谷子不育系及杂交种再生植株性状的表现

从谷子不育系及杂交种服性愈伤组织产生的再生植株当代和二代调查中,发现再生植株及后代普遍出现了株高降低、穗长缩短、穗型紧密和分蘖、分枝性增强的趋势。其中产生一些特殊表型株及株型好、抗虫性强的植株,再生不育株不育度提高,再生杂交种R_2代出现了三个饱满度好的大粒性穗行。     

Pollen donor impact on progenies of pseudogamous blackberries (Rubus subgen. Rubus)

A series of intra- and interspecific crosses in Rubus was evaluated with DNA markers to assess the proportion of apomictically vs. sexually derived progeny plants. The species were well separated from each other with these markers and the interspecific hybrids were easy to ascertain. Ten plants each were derived by selfing of R. hartmanni, R. polyanthemus and R. vestitus, and evaluated with RFLP. Of these plants, only one R. hartmanni plant appeared to be sexually derived, whereas the remainder appeared to have arisen by apomixis. Between 10 and 19 progeny plants, derived by open pollination of R. Hartmanni, R. infestus, R. laciniatus and R. vestitus, respectively (total of 63plants), were evaluated with RFLP. Of these, 6 plants (approx. 10%) showed as lightly deviating band pattern, which may indicate sexual seed set but could also result from experimental artefacts. The three species combinations 1) R. hartmanni and R. sprengelii, 2) R. infestus and R. vestitus, and 3)R. laciniatus and R. polyanthemus were cross-pollinated reciprocally and the resulting progenies evaluated with RAPD (combinations 1 and 2)and leaf shape (combination 3). Combination1 produced 20% (3 out of 15 progenies)sexually derived progenies, combination 2produced 100% (26 progenies) and combination 3 produced 64% (16 out of 26progenies), respectively. The hybrid progenies appeared to have been derived through pollination of unreduced as well as reduced egg cells. The ability to produce interspecific hybrid progenies is most probably dependent upon the species combination. This revised version was published online in July 2006 with corrections to the Cover Date.     

Screening for low grain cadmium phenotypes in sunflower, durum wheat and flax

Cadmium (Cd) level in nonoilseed sunflower (Helianthus annuus L.), flax (Linum usitatissimum L.), and durum wheat (Triticum turgidum L. var. durum) grown on uncontaminated, alkaline soils has exceeded limits established in Northern Europe. Separate field experiments were conducted to investigate variability of grain Cd levels among sunflower, durum wheat and flax germplasm, and to seek an efficient screening method for future breeding. There were large variations in leaf Cd concentration among 200 sunflower lines. These lines performed more consistently for Cd uptake at the R5 stage than at the V8 stage across 4 locations with markedly differing soils. Cd concentration in V8 leaves was not related to Cd in grain. The positive correlation between R5 leaf Cd and kernel Cd level was obtained from nonoilseed hybrid (Sigco 954) (R²; = 0.74**), and 200 lines (R² = 0.44**) tested over 4 locations in 2 field trials, respectively. This indicates that an efficient and low cost screening method can be developed for genotype selection, but plants must be grown to the R5 stage. A preliminary evaluation of 30 durum wheat and 74 flax lines indicated large variations in grain Cd level of durum wheat and flax. Grain Cd concentration ranged from 0.11 to 0.34 mg Cd kg^-1 DW for durum wheat, and 0.14 to 1.37 mg Cd kg^-1 DW for flax, respectively. This variability indicates that breeding for low grain Cd in durum wheat and flax should be feasible. This revised version was published online in July 2006 with corrections to the Cover Date.     

组织特异表达启动子RSS1P在转TiERF1基因小麦中的应用

从水稻叶片中克隆了一个韧皮部组织特异表达的水稻蔗糖合酶启动子(RSS1P),将RSS1P与中间偃麦草乙烯反应因子基因TiERF1相融合构成组织特异表达的TiERF1基因表达盒,取代pAHC20中Ubi::bar基因表达盒,构建成无选择标记的韧皮部组织特异表达的pA20-RSS1P::TiERF1载体。利用基因枪将pA20-RSS1P::TiERF1与pAHC20载体混合、共轰击小麦品种扬麦12的幼胚愈伤组织,获得转RSS1P::TiERF1基因小麦。对该转基因小麦T₀和T₁代植株进行PCR、PCR-Southern、半定量RT-PCR和荧光定量PCR分析,证实外源RSS1P::TiERF1基因已转入受体,并且具有可遗传性;转入的RSS1P::TiERF1基因仅在根、茎、叶中表达,以根部表达量最高,在种子内不表达。纹枯病抗性鉴定和主要农艺性状考察结果表明,与受体扬麦12相比,转RSS1P::TiERF1基因小麦对纹枯病的抗性有明显提高,与转Ubi::TiERF1基因小麦的抗病性相当,而且转RSS1P::TiERF1基因小麦的农艺性状没有明显改变,说明可以利用RSS1P启动子创造更实用的转基因小麦新种质。