加快淮北地区杂交粳稻发展的几个问题

回顾了淮北地区十多年来杂交粳稻示范推广的发展过程，分析了影响杂交粳稻发展的主要原因，并论述了加快该地区杂交粳稻发展的几个主要问题。     

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.     

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。     

Alternative Route of Infection for Bacterial Seedling Blight of Rice Caused by Burkholderia plantarii

Burkholderia plantarii , the pathogen of bacterial seedling blight of rice, was detected in paddy water. Its concentration rose in July and August. The bacterial concentration in the paddy water was always higher along levees than at distances more than 5 m from levees. Confirmed to be released into water when graminaceous weeds were immersed, B. plantarii survived for at least 4 days at 30°C. B. plantarii was splashed at least 30 cm upward by rain splash in the field. Harvested seeds, which had been sprayed with B. plantarii released from graminaceous weeds at the flowering stage, retained the bacteria. Bacterial seedling blight occurred when the seeds were then sown in nursery boxes. These results indicated that graminaceous weeds growing on levees of paddy fields are a source of infection of the disease and that rice seeds are infected through the paddy water. Received 23 May 2002/ Accepted in revised form 1 September 2002     

Growth and development of Cuscuta chinensis Lam. and its impact on selected crops

The growth and development of Cuscuta chinensis Lam., and the effects of the holoparasite on the growth and yield of tomato ( Lycopersicon esculentum ), chilli ( Capsicum annuum ) and rice ( Oryza sativa ) were investigated in pot experiments under glasshouse conditions. 'Mature' and 'immature' seeds of C. chinensis showed 15 and 47% germination, respectively. The independent life duration of seedlings from 'immature' seeds was 6 days shorter than 'mature' seeds (19 days). Cuscuta chinensis formed haustoria on chilli and tomato, but not on rice seedlings. Infection with three C. chinensis seedlings per host plant reduced leaf area, dry weight, carbon and nitrogen content by 78–84% and 27–44% in tomato and chilli plants, respectively. Dry weight of C. chinensis was 0.63 g per pot in tomato, and 0.24 g per pot in chilli. Carbon and nitrogen content of C. chinensis was 0.189 and 0.028 g per pot, respectively, when grown with tomato. When it was grown with chilli, the carbon and nitrogen content of C. chinensis was 0.001 and 0.007 g per pot, respectively. Cuscuta chinensis reduced the fruit yield of tomato and chilli by 72 and 29%, respectively. The results indicated that tomato is a preferred host of C. chinensis compared with chilli, and rice is not preferred. In the host–parasite associations, C. chinensis suppressed growth and yield of chilli and tomato by diverting the elaborated products of metabolism of the hosts.