气象因子对甘蔗种茎出苗率以及苗期生长的影响

为了探明影响广西甘蔗种茎出苗及苗期生长的气象因子,本研究选用2个广西当家甘蔗品种‘新台糖22号’（T22）和‘桂糖42号’（G42）为研究对象,从2—5月开展甘蔗分期播种试验,每半个月播种1期。通过观测每期甘蔗的出苗率、苗期生长状况以及同期的气象因子（降雨量、平均气温）,并对数据进行相关统计分析。结果表明,T22、G42蔗种的出苗率与播种后20 d的累积降雨量呈显著正相关,而与播种后10 d的累积降雨量呈正相关,差异未达显著水平。由播种后20 d的累积降雨量与甘蔗出苗率的对数函数方程进一步显示,为了使甘蔗种茎出苗率达80%以上,甘蔗播种后20 d的累积降雨量要达到75 mm以上;播种后的平均气温、降水量和日照时数与甘蔗苗茎伸长期株高/茎粗相关性达到5%显著性水平以上,进一步逐步回归分析显示,降水量是影响甘蔗茎伸长期株高/茎粗的显著性自变量。推断甘蔗播种后10~20 d的累积降雨量是决定甘蔗出苗的关键气象因子,在甘蔗苗期生长过程中,降雨量对甘蔗生长至关重要,可以通过降雨量预测甘蔗苗期株高/茎粗。鉴于以上研究结果,在广西甘蔗生产过程中,为了提高甘蔗出苗率,要加强甘蔗种植后20 d内的水分管理,在这期间累积降雨量需达到75 mm以上才能达到甘蔗齐苗的目的,甘蔗出苗后也需加强水分管理,利于苗期快速生长,从而提高蔗苗质量。     

穴盘育苗播种机械及技术发展研究

随着我国蔬菜、瓜果及花卉生产向专业化、规模化转变,育苗产业化必将成为今后的发展趋势。穴盘育苗是主要的育苗方式,阐述国内外穴盘育苗播种装置及播种技术的研究现状,分析我国穴盘育苗播种装置发展中存在的问题,预测其发展趋势,为后续高效、低成本穴缸育苗精量播种机械的设计提供参考。     

QTLs for Waterlogging Tolerance at Germination and Seedling Stages in Population of Recombinant Inbred Lines Derived from a Cross Between Synthetic and Cultivated Wheat Genotypes

Waterlogging is a widespread limiting factor for wheat production throughout the world. To identify quantitative trait loci （QTLs） associated with waterlogging tolerance at early stages of growth, survival rate （SR）, germination rate index （GRI）, leaf chlorophyll content index （CCI）, root length index （RLI）, plant height index （PHI）, root dry weight index （RDWI）, shoot dry weight index （SDWI）, and total dry weight index （DWI） were assessed using the International Triticeae Mapping Initiative （ITMI） population W7984/Opata85. Significant and positive correlations were detected for all traits in this population except RLI. A total of 32 QTLs were associated with waterlogging tolerance on all chromosomes except 3A, 3D, 4B, 5A, 5D, 6A, and 6D. Some of the QTLs explained large proportions of the phenotypic variance. One of these is the QTL for GRI on 7A, which explained 23.92% of the phenotypic variation. Of them, 22 alleles from the synthetic hexaploid wheat W7984 contributed positively. These results suggested that synthetic hexaploid wheat W7984 is an important genetic resource for waterlogging tolerance in wheat. These alleles conferring waterlogging tolerance at early stages of growth in wheat could be utilized in wheat breeding for improving waterlogging tolerance.     

In vitro Selection of DNAAptamers and Fluorescence-Based Recognition for Rapid Detection Listeria monocytogenes

Aptamers are specific nucleic acid sequences that can bind to a wide range of nucleic acid and non-nucleic acid targets with high affinity and specificity. Nucleic acid aptamers are selected in vitro from single stranded DNA or RNA ligands containing random sequences of up to a few hundred nucleotides. Systematic evolution of ligands by exponential enrichment （SELEX） was used to select and PCR amplify DNA sequences （aptamers） capable of binding to and detecting Listeria monocytogenes, one of the major food-borne pathogens. A simplified affinity separation approach was employed, in which L. monocytogenes in exponential （log） phase of growth was used as the separation target. A fluorescently-labeled aptamer assay scheme was devised for detecting L. monoeytogenes. This report described a novel approach to the detection of L. monocytogenes using DNA aptamers. Aptamers were developed by nine rounds of SELEX. A high affinity aptamer was successfully selected from the initial random DNA pool, and its secondary structure was also investigated. One of aptamers named e01 with the highest affinity was further tested in aptamer-peroxidase and aptamer-fluorescence staining protocols. This study has proved the principle that the whole-cell SELEX could be a promising technique to design aptamer-based molecular probes for dectection of pathogenic microorganisms without tedious isolation and purification of complex markers or targets.     

华阴市小麦“3414”试验研究

[目的]为了提出适宜华阴市小麦配方施肥方案.[方法]对小麦“3414”肥效试验结果进行分析,探索氮磷钾不同与小麦产量的关系.[结果]确定适宜华阴市小麦最高产量和最佳产量的施肥模式和目标产量,同时确定单因子肥效效应方程.[结论]该研究可以为华阴市小麦测土配方施肥提供依据.     

天优3301作烟后稻机械化插秧高产栽培技术

介绍了天优3301的特征特性及作烟后稻的产量表现,并总结其作烟后稻机械化插秧高产栽培技术.     

湖北省小麦适宜播期的叶龄积温法确定

为探明气候变暖背景下湖北省各地小麦适宜播期,同时为鄂北地区小麦亩产千斤提供理论支撑,本研究对2008~2012年湖北省郧西等10个地区的气象数据进行了分析,依据在前期研究基础上提出的湖北省小麦主导品种郑麦9023的叶热间距,运用叶龄积温法推算得出郧西等10个地区的小麦适宜播期。生产上各地可根据此次研究结果,结合当地气象预报、土壤墒情以及小麦品种特性等适当调整小麦播期,确保小麦壮苗越冬、高产稳产。     

我国红枣去核机的研究现状与发展趋势

红枣加工产品对于红枣销售渠道的拓宽、红枣产业化链条的延长具有重要意义。去核作为红枣精深加工生产中的关键环节,使用优质、高效的去核机可以大大降低红枣去核的劳动强度、提高生产效率、保证去核红枣的安全卫生。主要介绍了目前我国红枣去核机的发展现状,指出了市场上现有各种去核机产品在实际生产过程中存在的问题,分析了我国红枣去核机的发展趋势。     

玉米自交系辐3018的选育及其应用

为了创造更多更好的玉米基础材料,用60 Co-γ射线105Gy剂量照射国外杂交种干种子,用KL3回交后,采用常规育种方法选育出配合力高、抗病性强、早熟的玉米自交系辐3018,用其作亲本育成了龙辐玉7号、龙辐玉8号和龙辐玉9号等玉米杂交种。     

白桦次生林4个林龄0～30cm土层水源涵养功能比较

以小兴安岭地区白桦次生林4个林龄为研究对象,对其凋落物持水量、土壤贮水性能、土壤特性等进行研究.试验表明：4个林龄凋落物的蓄积量和最大持水量是70 a为最低,40 a为最大;土壤非毛管孔隙度在各林龄间变化呈波动性,30 a白桦次生林0～30 cm土层非毛管孔隙最小,不利于水分下渗,40 a白桦次生林0～ 30 cm土层非毛管孔隙最大,有利于降水的下渗,土壤水源涵养功能大小排序为40 a（3 276.820 t·hm-2）＜30 a（3 434.626 t·hm-2）＜50 a（3 525.015 t·hm-2）＜70 a（3 629.445 t·hm-2）.