白蜡杆软化和防蛀技术研究

白蜡(Fraxinus chinenesis)为木犀科(Oleaceae)白蜡树属(Fraxinus)的树种,落叶乔木或灌木。主要分布在西南、华中、华东、华北等地区。因白蜡杆木材具有材色浅、结构细、纹理直、软硬度适中、韧性好、可任意造型等优点,广泛用于农具、家具,特别适于弯曲部件、工艺品和文休用品的制作。自90年以来,以蜡杆、蜡条为主要原料生产高档工艺家俱的工作已经起步,但由于生产过程中缺乏合理实用的软化工艺及设备、防蛀工艺及设备,关键技术缺乏研究,不仅生产效率低,产品的内在质量无法改善,而且残次品率高,虫蛀率也高达80%以上。该研究提出了以蒸汽软化处理工艺、负压浸注防蛀工艺技术,既有效的软化了白蜡杆,同时达到了防蛀要求,产品的内在质量得到了改善。     

野菊嫩茎的组织培养

在适宜的培养条件下,利用野菊花的嫩茎作为外植体,用组织培养的方法,在MS培养基上生长良好,获得再生植株.练苗后,成活率达100%,生长势强,茎粗壮叶色浓绿.结果表明:利用组织培养的方式对野菊花进行扩繁,简便易行.     

不同白肋烟品种叶面腺毛密度的动态变化

以6个白肋烟品种为材料,对烟叶成熟过程中叶面腺毛形态和密度的变化规律进行了跟踪研究.结果表明,叶面总腺毛密度随着烟叶的成熟呈下降趋势.移栽后56～86天,长柄腺毛密度逐渐减少,短柄腺毛密度明显下降.不同品种间腺毛密度差异明显,不同部位腺毛密度表现为上部叶＞中部叶.长柄腺毛是白肋烟叶片上腺毛的主要类型.随着烟叶成熟,长柄腺毛所占比例逐渐增加,腺毛头部的分泌物增多充盈,到过熟期,腺毛萎缩、衰老和脱落的速度加快.     

Response of Vitis vinifera cv. ‘Tempranillo’ to partial rootzone drying in the field: Water relations, growth, yield and fruit and wine quality

This paper reports the effects of irrigation amount and partial rootzone drying (PRD) on water relations, growth, yield and wine quality of Vitis vinifera cv. ‘Tempranillo’ during two consecutive years in a commercial vineyard with a deep, light-clay soil located in Requena, Valencia, Spain. Partial rootzone drying applied at two amounts (100% and 50% of the estimated crop evapotranspiration), was compared to conventional drip irrigation, and also to rainfed vines. Results showed that the effects of irrigation amount on yield and wine quality were different between years. In 2003 with low yield values (around 6.3 t ha⁻¹) irrigation did neither affect grape production nor wine quality. However, in the following year, with much higher general yield (17 t ha⁻¹), the high irrigation dose increased yield by 30% compared to rainfed vines and it also increased must total soluble solids and wine alcohol content. In both seasons, PRD did not significantly affect physiological parameters, nor growth, yield or fruit and wine quality, when compared to the same amount of water applied by conventional drip irrigation. Overall these results suggest that, under our experimental conditions, it was the irrigation amount rather than the system of application what affected vine performance, indicating the difficulties of successfully employing the PRD type of irrigation with a drip system in heavy and deep soils.     

估测木薯茎叶生物量的一数学模型

为构建木薯茎叶生物量的估测模型,调查了木薯上、中、下部的茎粗、株高、叶柄长等形态学指标与茎叶生物量的关系.结果表明,木薯茎叶生物量主要受下部茎粗和株高的综合影响,并且下部茎粗、株高与茎叶生物量的关系均为乘幂函数关系.通过模型拟合和择优得到木薯茎叶生物量的估测模型W=0.032 83d2.48 6h0.1824.经新的实测数据检验,理论值与实测值的相对误差率为4.46%,完全满足测量精度要求.     

烟叶编持机的设计与开发

为了解决人工编烟费时、费力,效率低下的问题,设计开发了摆动钩针式烟叶编持机,设计编烟速度为12～20s/m可调,铺叶厚度和编叶数量可自动调整,综合辅助用工实际应用效率达手工编烟的5倍以上.编烟测试表明,该型编烟机编制均匀牢固,线迹美观,明显减少了编烟用工,具有较好的应用前景.     

打顶留叶数与烤烟品种TSNA形成累积的关系

为了探明降低烟草中的TSNA(烟草中的特有亚硝胺)含量的技术措施,该文通过对三个烤烟品种K326、红大、云烟85进行不同打顶留叶数处理,采用国际标准分析方法,对其鲜叶及成熟叶样品进行TSNA分析检测,以期发现它们之间的变化规律。结果表明:三个烤烟品种的TSNA的形成积累主要是在叶片成熟阶段,鲜叶中的含量很低。盛花期打顶能够降低K326及红大烤烟品种TSNA的形成积累,降幅分别为11.3%、10.3%;见花打顶能够降低云烟85烤烟品种TSNA的形成积累,降幅为4.9%。三个烤烟品种K326、红大、云烟85的四种亚硝胺含量在成熟的叶片中;NNK含量最高、NAT第二、NNN第三、NAB含量最低,正常打顶的三个烤烟品种,NNK含量占总TSNA的60%￣70%之间。     

毕节地区烤烟化学成分分析

对毕节烟区8个主产烟县所产烤烟烟叶C3L、C3F的10个常规化学成分进行了全面分析。结果表明:全区烤烟除钾离子和氯离子含量略偏低外,蛋白质、总氮、烟碱都处于合理水平,化学成分协调性好;县际间除氯离子(赫章、金沙平均最高,0.35%,威宁最低0.20%)、钾离子(大方1.84%,毕节市1.37%)和烟碱(金沙最高3.02%,赫章最低1.62%)差异较大外,其余化学成分差异不太大。     

Determining reference values for stem water potential and maximum daily trunk shrinkage in young apple trees based on plant responses to water deficit

The use of plant water status indicators such as midday stem water potential (Ψ_stem) and maximum daily trunk shrinkage (MDS) in irrigation scheduling requires the definition of a reference or threshold value, beyond which irrigation is necessary. These reference values are generally obtained by comparing the seasonal variation of plant water status with the environmental conditions under non-limiting soil water availability. In the present study an alternative approach is presented based on the plant’s response to water deficit. A drought experiment was carried out on two apple cultivars (Malus domestica Borkh. ‘Mutsu’ and ‘Cox Orange’) in which both indicators (Ψ_stem and MDS) were related to several plant physiological responses. Sap flow rates, maximum net photosynthesis rates and daily radial stem growth (DRSG) (derived from continuous stem diameter variation measurements) were considered in the assessment of the approach. Depending on the chosen plant response in relationship with Ψ_stem or MDS, the obtained reference values varied between −1.04 and −1.46 MPa for Ψ_stem and between 0.17 and 0.28 mm for MDS. In both cultivars, the approach based on maximum photosynthesis rates resulted in less negative Ψ_stem values and smaller MDS values, compared to the approaches with sap flow and daily radial stem growth. In the well-irrigated apple trees, day-to-day variations in midday Ψ_stem and MDS were related to the evaporative demand. These variations were more substantial for MDS than for midday Ψ_stem.     

延安市现代烟草农业建设与发展的思考

延安市现代烟草农业发展已初具规模,在论证出延安烟叶可持续发展必须坚持“发扬延安精神、做强延安烟草”、坚持“巩固、规范、创新、发展”的方针,运用现代科学技术和先进管理方法,确保延安烟叶持续、稳定、健康发展。