氮肥与复硝酚钠复配对南方大豆光合特性和产量及品质的影响

为确定南方大豆增产增效的栽培管理措施及光合特性与产量品质的相关性,本研究以5个南方主栽大豆品种为材料,于初花期（R1）和鼓粒期（R5）进行叶面喷施不同浓度的尿素和复硝酚钠,试验设置5个处理,3个种植区域,每个种植区3次重复,通过2年的数据,研究了叶面喷施氮肥以及氮肥与复硝酚钠复配对南方大豆品种产量、品质以及光合特性的影响。结果表明,增施氮肥可以提高南方大豆各品种的叶绿素SPAD值、净光合速率等光合特性,可提高单株有效荚数、单株粒重等产量构成因素进而提高大豆的产量;同时,氮肥与复硝酚钠复配与单独施用氮肥相比可使油6019、中豆44、中豆41和中豆63的产量增加,对脂肪和蛋白含量影响较小,对高蛋白品种皖豆28未起到增产的效果,但可使脂肪含量有所增加;经过氮素处理后,油6019的产量与品质呈现正相关性。综上所述,氮肥与复硝酚钠复配喷施具有进一步协同提高南方大豆品种产量和品质潜力,但由于对不同品种作用效果存在差异,针对不同基因型大豆品种需要制定最佳的处理方案。     

淡水小龙虾头中甲壳素的EDTA法提取工艺研究

以淡水小龙虾头为原料,采用EDTA法提取甲壳素,在单因素试验的基础上,通过正交试验筛选最佳工艺条件。试验结果表明:以13%的EDTA溶液作提取溶剂,在反应温度30℃、pH 12、投料比1∶15、反应25 min的条件下,提取效果最佳,提取率达24.05%,反应前后的脱钙和脱蛋白率分别为100.0%和98.6%。     

影响近红外对油菜种子品质分析的几个因素

[目的]为了研究样品本身的因素.[方法]通过试验及人为制造油菜种子异样,并通过其与正常样品的近红外品质分析结果比对,探讨样品量、含水量、发霉率、芽粒率以及成熟度对近红外品质分析结果的影响.[结果]样品量、含水量、发霉率、芽粒率以及成熟度对近红外品质测定结果都有不同程度的影响.[结论]在用近红进行正常的品质分析时,应尽量做到待测样品在样品量、含水量、净度、成熟度等方面与定标样品保持一致.     

碳纳米管对水稻种子萌发和根系生长的影响

将辽粳294水稻种子和不同浓度的碳纳米管共培养,对水稻种子萌发和幼苗生长情况进行观察,研究碳纳米管对水稻种子萌发和幼苗生长的影响。结果表明,适当浓度的碳纳米管(50~100μg/mL)促进了水稻种子发芽、根系生长和根系活力。当碳纳米管浓度增加到150μg/mL时,根系活力较100μg/mL时降低,但仍略高于对照。说明较低浓度的碳纳米管可以促进水稻种子发芽、根系生长和根系活力,而高浓度的碳纳米管则可能产生毒害作用。     

Recovery of bioactive compounds from Pinus pinaster wood by consecutive extraction stages

Pinus pinaster wood samples, obtained at different positions of three healthy trees, were subjected to two sequential extractions using an Accelerated Solvent Extraction instrument. The first extraction was carried out with hexane (to remove lipophilic extractives) and the second one with acetone/water (95:5 v/v) to recover bioactive phenolic compounds, the target compounds of this study. The extracted fractions were assayed for total yield and composition. The extracts contained a spectrum of phenolic compounds (simple phenolics, phenolic stilbenes, flavonoids and lignans) and non-phenolic components (juvabiones, resin and fatty acids, steryl esters and triglycerides). The fractionation effects achieved by consecutive extractions and the recovery of bioactive phenolics are discussed.     

Soil water affects transpiration response to rainfall and vapor pressure deficit in poplar plantation

Influences of environmental factors on transpiration are interactive. Sensitivities of transpiration responses to both evaporative demand and rainfall under contrasting soil water conditions constitute the physiological basis of the drought tolerance of trees. Such knowledge is practically significant for plantation management, especially for irrigation management. We therefore conducted a 6-year study on the transpiration of a poplar plantation in temperate China to elucidate the existence and pattern of the influence of the soil water over stand transpiration responses to (1) vapor pressure deficit (VPD), the major indicator of air dryness and (2) the rainfall, in terms of total amount and event size. The results showed that the response of plantation transpiration (E _c ) to VPD was conditioned by soil moisture. There was a significant difference in the frequency distribution of maximum sap flux under contrasting soil relative extractable water. E _c after rainfall of different sizes varied under similar VPD. The increasing occurrences of only large rainfall events led to enhanced total E _c during the growing season, but prolonged rainless intervals did not lead to a continuous decrease of E _c , suggesting appreciable supplements from the soil water were present to sustain transpiration. In addition, the balance of soil water between replenishment and extraction also conditioned the influence of rainfall over subsequent E _c during the respective rainless intervals. Based on the E _c responses to VPD and rainfall under different soil moisture levels, irrigation that directly replenishes the deep soil layers in order to alleviate water stress on transpiration during the small-rain event-dominated growing season is an effective and water-saving approach to guarantee trees survival during drought period.     

阴香木材干燥特性研究

为掌握阴香木材的干燥特性,制定合理的干燥基准.利用百度试验法进行研究阴香木材的干燥特性,结果表明：阴香木材干燥速度为2级,较快;截面变形程度较轻,为1级;初期开裂较严重,为3级;扭曲等级为3级,无内裂.针对阴香木材的干燥特性,参照百度试验缺陷等级以及干燥缺陷对应的干燥条件拟定25～ 30 mm厚阴香木材的干燥基准.在实际的窑干生产中只需对拟定的干燥基准进行适当的调整和优化便可以得到适合于阴香木材的干燥基准,提高干燥基准的制定效率,为促进阴香木材的开发和利用提供科学的理论依据.     

蝴蝶兰倍性与叶部和花部性状的相关性

【目的】研究蝴蝶兰Phalaenopsis倍性与主要性状的相关性.【方法】采用压片法对85份蝴蝶兰资源的倍性进行了鉴定,测量了这些资源的气孔长度、气孔密度、叶长、叶宽、叶厚、花朵直径和花朵数.【结果和结论】85份蝴蝶兰资源中3份为二倍体,占3.5%;9份为三倍体,占10.6%;73份为四倍体,占85.9%.四倍体蝴蝶兰的气孔长度和花朵直径显著大于二倍体和三倍体,而气孔密度和花朵数显著少于二倍体和三倍体(P0.05).三倍体蝴蝶兰的气孔长度、花朵直径和花朵数与二倍体蝴蝶兰差异均不显著(P0.05),但气孔密度显著小于二倍体(P0.05).四倍体蝴蝶兰的叶长显著大于二倍体(P0.05),但二倍体与三倍体、三倍体与四倍体在叶长上差异不显著(P0.05).二倍体、三倍体和四倍体在叶宽和叶厚上差异均不显著(P0.05).蝴蝶兰倍性与气孔长度、叶长和花朵直径呈极显著的正相关关系,与气孔密度和花朵数呈极显著的负相关关系.