低能氮离子注入对大豆幼苗脂质过氧化的影响

用N+注入丰豆101的种子,采收子叶伸展后24h和96h的幼苗做为试验材料,研究N+注入对其幼苗过氧化物酶(POD)、过氧化氢酶(CAT)和超氧化物歧化酶(SOD)活性以及氧化产物丙二醛(MDA)的含量、电解质外渗率的影响。结果表明,在25keV能量下,当N+注量在6.5×1016-7.8×1016N+/cm2时,幼苗的SOD和CAT活性最高。 而POD活性在小于5.2×1016N+/cm2低剂量下, 活性较恒定, 在大于5.2×1016N+/cm2中高剂量下,活性逐渐增大。此外,N+注入还可降低幼苗子叶中的MDA积累量和电解质外渗率,而且在6.5×1016N+/cm2剂量下,幼苗中的MDA含量和电解质外渗率最低。揭示了一定剂量N+注入大豆种子可削弱幼苗脂质过氧化作用以及提高其抗寒性的关系。     

N+注入对甘草叶片腺体和腺体分泌多糖及叶片多糖的影响

甘草叶片上生长有能分泌多糖的腺体,腺体分泌的多糖液累积于腺体头部呈透明"球状",功能叶上所有的腺体均向腺体头部分泌多糖液,枯黄衰老叶上的腺体头部仍然具有完整的呈"球状"的多糖液.对甘草干种子注入总量为4.68×1016/cm2、能量为10-25keV的N 对甘草叶片腺体数、腺体分泌多糖、叶内多糖、叶片总多糖均有刺激效应.其中15 keV的N 注入叶片腺体分泌多糖比对照提高44.1%(P＜0.01);甘草叶面腺体数和腺体分泌多糖呈明显的正相关(r=0.4537,P＜0.1).20keV的N 注入甘草叶片总多糖含量比对照提高31.8%(P＜0.01).这些N 注入甘草干种子的能量、注量参数可供对甘草进行离子束育种时参考.     

A Preliminary Study on a Specifically Expressed Arabidopsis Promotor in Vascular Bundle

From a population of about 3500 single plants is Arabidopsis promoter trapping bank,one plant whose GUS-gene had been specifically expressed in vascular bundle,was screened by the method of gus tissue staining.The T-DNA flanking sequence was amplified using TAIL-PCDR.This band will be purified and connected to TA cloning vector.After sequencing and searching in the genebank ,its function will be demonatrated through transformation.     

Preliminary Studies on Base Substitutions and Repair of DNA Mismatch Damage Stimulated by Low Energy N＋ Ion Beam Implantation in Escherichia coli

Ever since the low energy N+ ion beam has been accepted that the mutation effects of ionizing radiation are attributed mainly to direct or indirect damage to DNA. Evidences based on naked DNA irradiation in support of a mutation spectrum appears to be consistent, but direct proof of such results in vivo are limited. Using mutS, dam and/or dcm defective Eschericha coli imitator strains, an preliminary experimental system on induction of in vivo mutation spectra of low energy N+ ion beam has been established in this study. It was observed that the mutation rates of rifampicin resistance induced by N+ implantation were quite high, ranging from 9.2×10-8 to 4.9 ×10~5 at the dosage of 5.2 ×1014 ions/cm2. Strains all had more than 90-fold higher mutation rate than its spontaneous mutation rate determined by this method. It reveals that base substitutions involve in induction of mutation of low energy nitrogen ion beam implantation. The mutation rates of mutator strains were nearly 500-fold (GM2929), 400-fol     

玉米对生性状两个显性基因SCAR分子标记

把与玉米对生叶突变体对生性状两个显性位点紧密连锁的RAPD标记S312377与S360602成功地转化成SCAR标记CBJ1与CBJ2。对RAPD片段的纯化、T－A克隆、SCAR PCR引物的设计等SCAR标记转化进行了探讨，并对CBJ1与CBJ2进行了验证，为对生玉米的分子标记辅助选择与定位克隆奠定了基础。     

A Preliminary Study on a Specifically Expressed Arabidopsis Promoter in Vascular Bundle

From a population of about 3500 single plants in Arabidopsis promoter trapping bank, one plant whose GUS-gene had been specifically expressed in vascular bundle, was screened by the method of gus tissue staining. The T-DNA flanking sequence was amplified using TAIL-PCR. This band will be purified and connected to TA cloning vector. After sequencing and searching in the genebank, its function will be demonatrated through transformation.