光敏核不育水稻选育与利用的几个问题讨论

对现有光敏核不育材料进行了分类,分为４种遗传类型;其中,温光弱感到光敏核不育系是最为理 想的遗传工具,并就其选育途径和选择“粳不籼恢”繁殖制种技术体系进行了论证．     

“复激保果剂”在杂交水稻制种上应用技术总结

复激保累剂,在杂交稻制种上使用,能促使花器发育良好,调节父母本花期,提高结实率,增加每穗实粒和粒重,提高产量。且成本低,有显著的经济效益。     

黑米天然黑(紫)色素的研究

特种稻黑米品种的糙米果皮中,含有大量的稀有天然黑(紫)色素。本文研究了这种色素的提取与分离方法、化学结构及其稳定性,并对其药理作用和应用前景作了简要分析。     

Red rice (Oryza sativa L.) and barnyardgrass (Echinochloa spp.) biotype susceptibility to postemergence-applied imazamox

Pot experiments were conducted to evaluate the level of imazamox tolerance in five red rice ( Oryza sativa L.) and four barnyardgrass (three Echinochloa crus-galli (L.) Beauv. and one Echinochloa oryzoides (Ard.) Fritch) morphologically distinct biotypes collected from rice fields in northern Greece. The susceptibility of barnyardgrass biotypes to propanil was also studied. Red rice biotypes were not controlled by imazamox applied at 40 g ha⁻¹. In contrast, 80 g imazamox ha⁻¹ provided 56–84% red rice control (averaged across shoot number and fresh weight reduction). Not all barnyardgrass biotypes were susceptible to imazamox applied postemergence. However, propanil applied at 2.6 kg ha ⁻¹ controlled the E. crus-galli biotypes well, but propanil applied at rates of 2.6 and 5.2 kg ha ⁻¹ was not effective in reducing the shoot number and fresh weight of the E. oryzoides biotype. Propanil applied at 10.4 kg ha ⁻¹ reduced the shoot number and fresh weight of this biotype by 78 and 85%, respectively. In most cases, a linear equation ( y  = % of control, x  = g ha⁻¹) provided the best fit for regressions between red rice or barnyardgrass shoot number or fresh weight and imazamox rates. The results of this study suggest that postemergence application of imazamox is not effective against all red rice and barnyardgrass biotypes found in the rice fields of Greece and that significant variability regarding herbicide efficacy among biotypes might exist.     

A molecular phylogeny of wild and cultivated Echinochloa in East Asia inferred from non-coding region sequences of trnT-L-F

The phylogenetic relationship among 30 accessions belonging to nine species of the genus Echinochloa Beauv. was studied on the basis of the sequence of three non-coding regions ( trn T-L, trn L-F intergenic spacers, and trn L intron) of chloroplast DNA (cpDNA). A strict consensus parsimonious tree of the three most parsimonious trees derived from 25 polymorphic sites (six indels and 19 substitutions) in the total sequences, ranging from 1715–1760 bp, represented five groups: (i) Echinochloa oryzicola Vasing. and Echinochloa stagnina Beauv. from Thailand; (ii) Echinochloa crus-galli Beauv. complex; (iii) Echinochloa crus-pavonis Schult; (iv) Echinochloa colonum Link. and Echinochloa frumentacea Link.; and (v) the African species, Echinochloa obtusiflora Stapf and Echinochloa stagnina . Japanese barnyard millet ( Echinochloa esculenta H. Scholz) and various weedy varieties of E. crus-galli and Echinochloa oryzoides Fritsch had quite similar sequences and formed the E. crus-galli complex, which was characterized by six substitutions. A cultivated form of E. oryzicola (Mosuo barnyard millet) and various morphological and agronomical forms of E. oryzicola were characterized by two indels. Indian barnyard millet ( E. frumentacea ) and its wild counterpart ( E. colonum ) were characterized by five substitutions. Domestication as millets and adaptation to paddy environments as mimic weeds might occur after the divergence of species in the Asian Echinochloa .     

西北干旱区生态环境建设支撑体系的构建

西北干旱区的自然环境脆弱性叠加不合理的水土资源开发等人类活动干扰是导致区域生态环境日趋恶化的根本原因,已严重制约社会经济的可持续发展。针对当前生态环境建设实际,提出应在实现水资源可持续利用、建立完善的管理体制及法律体系、调整产业结构、积极推进城镇化进程、大力发展科技教育等方面采取有力措施。以此为重要支撑,恢复与重建受损生态系统,改善区域生态环境,实现环境与经济社会协调发展。     

菌根与植被恢复

菌根不仅可促进植物的营养吸收、生长发育、抗病、抗逆,而且在保持良好的土壤结构、控制水土流失方面具有直接的作用。在我国西北许多地区,菌根菌与植物间的共生关系已被中断,要恢复该地区的植被,治本的方法应是重建植物与菌根菌的共生关系,形成健康的生态系统。文中还提出了菌根技术在植被恢复中的应用策略。     

水稻旱作对其生长量和经济产量的影响

1998～1999年，研究了水稻旱作条件下，不同生育时期受水分胁迫后对作物生长量的影响。结果表明：不同指标对水分胁迫时期的敏感性不一，植株高度对抽穗期水分胁迫最敏感；单株绿叶面积和单株地上部干重对幼穗分化后期水分胁迫最敏感；根系干重和根冠比对幼穗分化前期水分胁迫最敏感；幼穗分化后期水分胁迫对经济产量影响程度最大，无效分蘖期水分胁迫对产量影响程度最小。     

乌鲁木齐区域水资源利用中的生态经济问题及其调控对策

本文在考察乌鲁木齐区域水资源利用现状的基础上 ,从生态经济学的角度总结和分析了该区域水资源利用中存在的问题 ;针对问题 ,提出了相应的调控对策。     

Quick detection of sex determining region protein gene in mouse fetuses

AIM: To detect quickly the Y-chromosome specific sex determining region protein (Sry) gene in mouse fetuses on embryonic day 14.5 with a PCR method. METHODS: We designed specific primers with the OLIGO 5. 0 software. Templates were prepared in 30 minutes by the following way. About 1 mg embryonic tissue but not fetal liver was suspended, and treated with 200μL of lysis buffer, consisting of PCR buffer containing 20 mg/L proteinase K, 0. 5% NP-40, and 0.05% Tween 40, at 60°C for 15 minutes, heated for 5 minutes at 100 °C, 10μL was used as template. The PCR react ion was performed in 50μL, using two sets of primers specific for Sry gene (chromosome Y) and IL-3 gene (chromosome 11) . PCR conditions and cycle numbers were optimized. The assessment of the results was done by electrophoresis in 3% agarose run at high voltage. The specificity of the method was conf irmed by fluorescent in situ hybridization (FISH) using a specific male probe on embryonic tissue cells. RESULTS: Electrophoresis showed that PCR product of male control DNA consisted of a 649 bp product representing the IL-3 gene and a 444 bp product representing the Y-specific Sry gene, female control DNA only one 649 bp product. Fetuses with two bands matching those as seen inmale control DNA are the presumpt ive male fetuses. Fetuses, only the IL-3-associated 649 bp band, are the presumptive female fetuses. These were confirmed by FISH. The ent ire procedure took <3. 5 h. CONCLUSION: The established PCR assay offers a quick, simple, accurate, and sensitive detection of sex determining region protein gene in mouse fetuses. This method allowed the preparation and culture of pure male and female hematopoietic stem cells from fetal tissue.