水稻突变体B1-24的细胞学观察及其激素调控

以半矮化水稻突变体B1-24及其野生型惠阳珍珠早(Hyz)幼苗为材料,探究其细胞学特征及其对激素的响应.在光下生长的B1-24幼苗比Hyz矮14.62%,第一真叶长度短11.18%,黄化苗植株的中胚轴长度增长41.89%,但Hyz的胚芽鞘长度比之长28.71%.细胞学观察发现,与野生型相比,突变体第一真叶叶片细胞长度和宽度都无显著差异.B1-24黄化苗的胚芽鞘细胞长度仅为Hyz的45.95%,而中胚轴细胞长度是其118.28%.B1-24对激素GA3(600 μg/ml)和IAA(7 μg/ml)的处理敏感,其细胞长度显著增长,植株表型更接近Hyz.而50 μg/mL PAC处理使其严重缩短.推测B1-24的半矮化突变可能与激素合成或响应有关     

水稻突变体B1-24的细胞学观察及其激素响应

以半矮化水稻突变体B1-24及其野生型惠阳珍珠早(Hyz)幼苗为材料,探究其细胞学特征及其对激素的响应.在光下生长的B1-24幼苗比Hyz矮14.62%,第一真叶长度短11.18%,黄化苗植株的中胚轴长度增长41.89%.B1-24黄化苗的胚芽鞘细胞长度仅为Hyz的45.95%,而中胚轴细胞长度是其118.28%.B1-24分别经激素GA3(600μg/mL)和IAA(7μg/mL)处理,其细胞长度显著增长,50μg/mL PAC处理使其严重缩短.推测B1-24的半矮化突变可能与激素合成或响应有关.     

两种矮壮素水剂在高原春小麦上的应用效果

通过不同产地生产的50％矮壮素水剂在我省春小麦田的应用,表明矮壮素对春小麦的矮化作用显著,增强了作物的抗倒伏能力,有一定的增产作用,其适用剂量为3．0kg/hm^2。     

矮化中间砧大樱桃技术

目前大樱桃栽培当中，大部分仍沿用传统的乔化栽培方式，亩栽株数少，结果晚，产量低，质量差，严重影响了大樱桃的经济效益。1998年，大连得利高新果业有限公司承担的大连市科技重点攻关项目“大樱桃矮化砧木的筛选及其利用研究”，成功选育出FL-80矮化中问砧，培育出以毛樱桃做基砧FL-80做中间砧矮化大樱桃，达到国内领先水平；获得国家发明专利（ZL03133759．7），被列为星火计划重点推广项目。     

日光温室冬春茬黄瓜加行高矮秧密植技术（上）

黄瓜加行高矮秧密植种植，是指在曰光温室冬春茬黄瓜常规栽培的基础上，以原栽培行为主栽行，在主栽行之间加行密植的栽培模式。通过矮化整枝，增加前期密度，提高前期产量，待附加行得到一定产量，群体叶面积达到一定数量时，将附加行植株拔除，保证主栽行在适宜条件下生长，以达到增产增收的目的。其关键栽培技术如下：     

我国水稻育种的回顾与展望

概述了近年来国内有关水稻高产育种的研究成果，提出了水稻进一步超高产育种的技术策略应与当今和未来的超高产育种目标相一致，从而为确保水稻的大面积优势高产奠定了坚实的基础。     

ZY-1砧木对欧洲甜樱桃生长结果的影响

ZY-1砧木嫁接拉宾斯、斯坦勒、先锋、雷尼尔、龙冠、大紫和红灯,植株生长势降低,试花挂果期提早.二年生试花,三年生开花株率和结果株率分别达到52%～100%和41%～95%;四年生开花株率和结果株率均达到100%,最高单株产量和平均单株产量达到1.87～5.06 kg和0.31～1.36 kg.而以中国樱桃作砧木的红灯三年生才开始开花,四年生开花株率、结果株率、最高单株产量和平均单株产量仅分别为65%、51%、0.25 kg和0.02 kg,仅为以ZY-1作砧木的红灯的65.00%、51.00%、13.37%和6.45%.     

水稻矮化突变体G蛋白α亚基基因的结构和表达

利用γ-Co60辐射诱发水稻特光矮-2(Oryza sativa L.cv.TGA-2)产生变异,获得一种稳定遗传的新型水稻矮化突变体dwarf69.dwarf69和TGA-2及其杂交后代F1、F2、F3成熟期的株高数据表明矮化表型受一对隐性基因控制.进一步研究发现,虽然dwarf69和TGA-2的G蛋白α亚基基因(Rice G protein alpha-subunit,RGA)编码区核苷酸序列只有一个核苷酸的差异,但RGA在野生型TGA-2中的表达量明显高于在突变体dwarf69中的表达量.对矮化突变体dwarf69和野生型TGA-2的RGA基因5＇上游区的序列分析表明,dwarf69 RGA 5＇上游区比TGA-2RGA5＇上游区多出1076bp.首次报道水稻矮化突变体中的RGA5＇上游区序列与其野生种的RGA5＇上游区序列存在显著的差异.     

Southern rice black-streaked dwarf virus: A new proposed <Emphasis Type="Italic">Fijivirus</Emphasis> species in the family <Emphasis Type="Italic">Reoviridae</Emphasis>

For the past several years, a novel dwarf disease has been observed on rice （Oryza sativa） in some regions of Guangdong Province and Hainan Province, southern China. Infected plants showed stunting, dark leaf and small enations on stem and leaf back. Typical Fijivirus viroplasma containing crystalline arrayed spherical virons approximately 70--75 nm in diameter and tubular structures were detected in ultrathin sections by an electron microscope in parenchyma phloem cells of the infected plants. The virus was transmitted to rice seedlings by white-backed planthoppers, Sogatella furcifera （Hemiptera： Delphacidae）, collected in the diseased fields. Analysis of dsRNA extracts from infected plants revealed ten linear segments, which were similar to the electrophoretic profile of Rice black-streaked dwarf virus （RBSDV）. RT-PCR with a single primer which matched to a linker sequence ligated to both 3＇ ends of the viral genomic dsRNAs resulted in amplification of genome segments 9 （S9） and 10 （S10） cDNA products. The complete nucleotide sequences of S9 and S10 were obtained from clones of the RT-PCR amplicon exhibited characteristic properties of Fijivirus including low GC content （34.5% and 35.6%）, genus conserved 5＇ and 3＇ termini sequences and similar genome organization. Blast searches indicated that the sequences of S9 and S10 shared 68.8%--74.9% and 67.1% --77.4% nucleotide identities with those of viruses in the Fijivirus group 2, respectively. These values were similar to those among other viruses in the Fijivirus group 2 and considerably lower than those among RBSDV isolates. Phylogenetic trees based on S9 and S10 nucleotide sequences and their putative amino acid sequences showed that this virus represented a separate branch among other Fijiviruses. The virus was also detected by a nested RT-PCR assay in corn （Zea mays）, barnyard grass （Echinochloa crusgalll）, Juncellus serotinus and flaccidgrass （Pennisetum flaccidum） in and/or adjacent to the infected rice fields. I