盐胁迫对水稻发芽和出苗的影响

对123个不同水稻品种分别在纯水、100 mmol/L NaCl和150mmol/LNaCl水溶液中的萌发情况进行试验,研究盐对发芽率和出苗率的影响,以及不同品种对盐胁迫的不同反应,结果表明:水稻各品种在处理2、处理3的条件下的萌发都比处理1要晚,处理1、2、3的发芽率分别为94.24%、95.08%、85.91%,出苗率分别为90.21%、95.08%、0;盐胁迫对不同品种的发芽率和出苗率影响程度不同,品种之间的基因型差异是耐盐水稻筛选的基础。     

Effects of Seedbed Substrates on Regeneration of Picea abies from Seeds

The effects of seedbed substrates on the emergence and mortality of Norway spruce [ Picea abies (L.) Karst.] on clear-cuts were studied in a sowing experiment. Seven intact substrates as well as scarified plots on the same types of substrates were considered. The experiment took place at two locations in south-east Norway, during three consecutive years. Of intact substrates, Sphagnum spp. was found to be the best for emergence and litter was found to be the second best. Microhabitats dominated by feather mosses, Dicranum spp., Vaccinium myrtillus or Deschampsia flexuosa were poor environments for emergence. However, after two to three seasons, survival in per cent of emerged seedlings was more or less equal among all substrates. Emergence was higher on scarified plots than on intact substrates, and except for Sphagnum substrates, survival was equal or better. For scarified plots, the original substrate did not influence the emergence of seedlings, but mortality after the second summer differed owing to original substrate. The best substrates for scarification were V. myrtillus and D. flexuosa , while mortality was highest for plots that were originally dominated by Sphagnum . Weather conditions influenced the suitability of the substrates as seedbeds, as did the location of the plots.     

模糊矩阵在预测沙芥生长期菜蛾发生量中的应用

通过建立平均降雨量、平均气温与沙芥生长期菜蛾发生量之间的模糊矩阵,预测沙芥生长期菜蛾的发生量,验证结果表明:历史符合率达100%,且2005年预报与实际完全吻合。     

浸种时间对杂交稻种子出苗和幼苗生长的影响

[目的]考察浸种时间对杂交水稻种子出苗和幼苗生长的影响。[方法]以3个杂交稻品种的种子为试验材料,设置8个浸种时间处理,研究了浸种时间对水稻种子出苗和幼苗生长的影响。[结果]试验表明,浸种处理时间在3~7 d内,种子出苗率差异不显著,浸种时间达8~9 d后,种子出苗率明显降低。浸种时间对水稻幼苗高度的影响与对出苗率的影响基本一致,对幼苗叶龄、发根条数、根长和干物质积累的影响不明显。[结论]研究可为杂交水稻种子浸种时间的选择提供参考依据。     

冀北坝上不同土壤类型对燕麦出苗率的影响

通过对燕麦种子在不同土壤条件下发芽率测定与出苗率对比分析,明确了发芽试验方法及冀北坝上不同土壤条件下的出苗状况。结果表明:非种子生产条件下的燕麦品种发芽率较低,仅为85%左右,普通生产条件下收获的品种直接做种子应用存在风险;燕麦发芽率测定方式以沙培法最为稳定一致,应作为统一测定标准进行改进;影响燕麦出苗率的除种子因素外与土壤水分、盐分和土壤质量关系密切,与土壤类型关系不大。燕麦种子生产必须尽快提高发芽率,实行种子公司专业化生产,达到种子生产标准化、专业化,为实行科学精量播种创造条件。     

山药零余子EMS诱变处理的研究

旨在确定EMS诱变山药零余子的最佳处理浓度和时间。以‘晋山药1号’的零余子为材料,采用不同浓度EMS溶液和浸泡时间对零余子进行诱变处理,对处理后的零余子出苗率、成苗率、变异率进行比较。结果表明：当EMS溶液浓度小于0.5%,山药零余子的浸泡时间小于18 h,出苗率、成苗率、变异率随着浸泡时间延长趋势不变;浸泡时间大于18 h而小于36 h时,出苗率随着浸泡时间的延长呈现上升趋势,而变异率的趋势不变。EMS溶液浓度大于0.5%小于0.9%,且浸泡时间小于24 h,出苗率随着浸泡时间延长呈现下降趋势,变异率随着浸泡时间延长趋势上升。EMS溶液浓度等于0.9%,浸泡时间等于24 h,出苗率约为50%。EMS溶液浓度大于0.9%,浸泡时间大于30 h,变异率随着浸泡时间延长呈现下降趋势。综上,EMS诱变山药零余子的最佳处理浓度为0.9%、浸泡时间24~30 h。     

北疆临冬播小麦品种间生育特性及产量比较

为筛选出适合北疆临冬播小麦品种,采用田间试验,比较了18个小麦品种的出苗率、叶面积指数、干物质积累及产量等。结果表明,越冬期4cm最低地温为-7.93℃条件下,春小麦品种平均出苗率（53.23%）显著高于冬小麦品种（34.20%）,宁春系列品种的平均出苗率（60.83%）高于新春系列品种（42.67%）;冬小麦品种的平均生育期较春小麦品种长6d且晚熟,新春系列品种的平均生育期（103d）长于农麦和永良系列品种（88d）及宁春系列品种（92d）。新春48号和新冬41号出苗率分别45.60%和52.00%,基本苗数分别为342.00万和390.00万/hm²,穗数分别为459.00万和365.00万/hm²,穗粒数分别为34.90和33.84;叶面积指数峰值分别为3.96和3.52;总光合势分别为247.00和231.21(m²·d)/m²,干物质积累总量和经济系数均较高;生育期分别为104和106d;产量均显著高于其他品种。综合各项指标,新春48号和新冬41号适合北疆地区临冬播种。     

Effect of variety and seed dressing on emergence of high-oleic peanut under low temperature and high soil humidity conditions

Low temperature coupled with high soil moisture during sowing to emergence generally results in poor peanut stand, thereby posing a non-negligible threat to peanut production in north and northeast China. Five high-oleic (HO) peanut cultivars and 4 seed dressing treatments capable of controlling several diseases and insect pests along with untreated checks were used to find the best combinations to cope with the dual stresses during sowing to emergence period. High broad-sense hereditability estimates of seedling emergence indicated great potential for genetic improvement of this trait. Analysis of variance in the split-plot experiment showed that the main effects of variety and seed dressing and their interaction on seedling emergence were significant. Seed dressing treatments increased seedling emergence percentage by 2.09–35.00 percent points. Four of the 5 HO peanut cultivars yielded satisfactory results. For Huayu 665, Huayu 668 and Huayu 965, Huweisanbao may be the best option; for Huayu 962, Weilidan was highly acceptable. These combinations will be evaluated further in multiple environments before large-scale extension.     

马尾松种子生活力与发芽指标相关性的初步研究

马尾松(pinus massoniana)种子实验室发芽率与生活力之间存在线性相关,其数学表达式为y~(-1)=1.0756x~(-1)-0.000826。场圃发芽率与实验室发芽率、生活力之间也存在着线性相关,场圃发芽率与生活力之间存在着y~(-1)=1.144x~(-1)+0.0002375的关系。场圃发芽率与实验室发芽率存在着y~(-1)=1.2499x~(-1)-0.00189的关系。     

60Co-γ射线辐照及其与GA3复合处理对牡丹种子的诱变效果

为了研究60Co-γ射线对牡丹种子萌发及出苗率的影响,探讨牡丹种子辐射剂量问题,为开展牡丹品种诱变改良奠定基础,以不同剂量的60Co-γ射线及200 mg/L GA3处理牡丹种子,统计种子的发芽率、主根长以及出苗率。结果表明：牡丹种子的发芽率、主根长≥40 mm的百分率以及出苗率均随辐射剂量的增加呈现先增加后减少的趋势;GA3的辐射防护作用使得牡丹种子的最佳辐射剂量变大,26.28 Gy时,牡丹种子的发芽率、主根长≥40 mm的百分率及出苗率最高。同时低辐射也可提前打破牡丹种子的休眠,8.76 Gy时效果最佳。