30％已·乙水剂对玉米产量和茎秆质量的影响

30%已.乙水剂处理极显著缩短穗下部节间长度,降低了植株和果穗的重心,提高了子粒形成期和灌浆期穗下部节间单位长度干重,极显著提高穗下部节间折断时的最大载荷和径向的碾碎强度,增加了穗下各茎节的粗度,总体提高玉米茎的抗倒伏性能。同时,化控处理降低了空秆率和秃尖长,提高了行粒数和穗粒重,显著提高了产量,化控措施使玉米子粒产量与茎秆质量得到了协同改善。     

营养液浓度及pH值对山葵生长及光合速率的影响

 探讨了0.5、1.0、1.5 倍日本园试营养液3 种浓度(以清水为对照) 和5.4、6.0、6.6、7.2 等4 种pH 值对山葵生长和光合速率的影响。结果表明, 在营养液1.0 倍和pH 6.0 条件下, 山葵平均根茎鲜质量为42.75 g , 且叶绿素含量和净光合速率显著高于其它处理。     

Factors affecting in vitro adventitious shoot formation on internode explants of Citrus aurantium L. cv. Brazilian

The in vitro formation of newly formed adventitious buds and shoots from internodal branch segments was studied on 12-month-old plants of Citrus aurantium L. cv. Brazilian. The effects of 6-Benzyladenine (BA) and α-Naphthalene acetic acid (NAA) treatments were evaluated on adventitious bud and shoot regeneration. High rates of bud initiation and shoot development were obtained both with BA supplemented medium, in the range from 1 mg L⁻¹ to 3 mg L⁻¹, and with 0.1 mg L⁻¹ NAA supplemented medium. NAA concentrations above 1 mg L⁻¹ significantly reduced bud initiation and shoot elongation. The results obtained using different in vitro culture vessels such as Petri dishes, tubes and glass culture jars were compared. The highest adventitious bud induction was observed in Petri dishes for internodes cultured in 2 mg L⁻¹ BA supplemented medium, with 95% responsive explants forming 9.0 ± 2.4 adventitious buds. The adventitious buds observed in Petri dishes reached a maximum height of 1 mm, with no further development, while some of the adventitious shoots cultured in tubes and glass culture jars grew over 1 cm in height. A shoot regeneration gradient of the internodes collected along the branch axis was noticed, with basal ones exhibiting higher regeneration frequency.     

不同外援营养液对白灵菇生长的影响

以白灵菇菌株TN01为试材,选取香菇、杏鲍菇、白玉菇3种食用菌菇根为原料配制外援营养液,测定各营养液主要成分含量,并研究了不同类型与浓度营养液对白灵菇菌丝及子实体生长的影响,以期为白灵菇的高产栽培技术提供参考依据。结果表明:与常规PDA培养基相比,适量加入白玉菇菇根提取液可提高白灵菇菌丝生长速度;添加外援营养液对子实体的农艺性状影响不大,对产量有一定的促进作用,其中施用香菇菇根提取液的白灵菇子实体产量最高,小区总产量与对照相比提高了54.6%。施用香菇菇根提取液后对白灵菇子实体中的硝酸盐含量及蛋白质含量有提升的效果,但对亚硝酸盐及粗纤维含量无促增长的效果。     

不同浓度营养液浸泡保水剂对黄瓜幼苗生长和光合作用的影响

采用不同浓度营养液浸泡丙烯酰胺-丙烯酸盐(钾)共聚交联物(CAA),与蛭石混合配制成5种基质,研究不同基质对黄瓜穴盘苗的生长、叶绿素荧光参数、光合作用的影响。结果表明:随营养液浓度的增加,黄瓜幼苗的生长指标显著提高,净光合速率(Pn)、最大光化学效率(Fv/Fm)等光合作用指标显著增加;在5种基质处理中,处理5(总盐分浓度为10.98 g/L)效果最明显,幼苗生长指标、光合参数等均显著高于其它处理;表明使用高浓度营养液浸泡CAA与蛭石混合配制的育苗基质进行黄瓜育苗,既可以减少施肥次数,还能显著提高黄瓜的穴盘苗质量,可作为生产中草炭为主的栽培基质的替代品。     

木材干燥过程热质迁移数学模型研究现状

建立及求解木材干燥过程热质迁移数学模型的主要目的是为了对木材实际干燥过程进行预测和控制,对促进木材干燥技术的发展意义重大。本文主要从水分迁移、能量转移、应力应变与数值求解方法等方面,归纳总结了国内外木材干燥过程中热质迁移模型建立及求解的研究现状,根据木材干燥机理、热质迁移理论及干燥生产实际分析了模型可借鉴应用之处以及存在的问题,提出符合实际干燥情况的多维(2、3D)热质迁移以及考虑木材干缩现象的热质-应力应变耦合数学模型是今后的研究重点。      

Einfluss eisenhaltiger Klärschlämme auf Kenngrößen der P‐Verfügbarkeit in Ackerböden

Influence of iron content in sewage sludges on parameters of phosphate availability in arable soils The use of iron salts for the P elimination in sewage plants is widely used. But it is not clear whether the P availability in arable soils is negatively influenced by iron compounds or not. The aim of the investigations was, therefore, to study the influence of two sewage sludges with a high and a low Fe content respectively on P sorption and phosphate concentration (P_i) in the soil solution after application of CaHPO₄ or sewage sludge to 5 loamy and 4 sandy soils (pot experiments and 1 silty loam (field experiment)). Soils were analyzed 1, 6, and 13 months after P application. Sludge Gö contained 12 kg P and 65 kg Fe (t DM)^—1 (P : Fe = 1 : 5.4) and sludge Sh 25 kg P and 39 kg Fe (t DM)^—1 (P : Fe = 1 : 1.5). The basic P application was 60 kg P ha^—1 (= 30 mg P (kg soil)^—1 in the pot experiment, as sludge or as CaHPO₄). P uptake by maize was determined in a separate pot experiment with a loamy soil and the same P application rate. The P sorption capacity remained similar in all soils after application of sludge Sh (P : Fe = 1:1.5) compared with soils without sludge, however, after application of sludge Gö the P sorption increased by 16% (0—59%). After application of sludge Sh the mean P_i concentration increased in loamy soils by 34% and in sandy soils by 15%. On the other hand the P_i concentration decreased after applying sludge Gö by 13% and 36% as compared to the controls of the respective soils. In the field experiment the P_i concentration of plots with a high P level (50 mg lactate soluble P (kg soil)^—1) was also significantly decreased after application of 10 t sludge Gö (126 kg P ha^—1) in comparison with triple phosphate. One month after the application of increasing amounts of sludge Gö (5, 10, 15 t DM ha^—1) both the concentration of oxalate‐soluble Fe in the soil and the P sorption were increased. The elevated relationship between these two parameters was highly significant (r² = 0.6 — 0.97). Plant uptake of P was less after application of sludge Gö than after application of sludge Sh and much less than P uptake from CaHPO₄. Sewage sludges with a P : Fe ratio of 1 : 5 should not be recommended for agricultural use, as the P availability is significantly reduced. Iron salts should not be used for conditioning of sludges.     

柱前衍生化高效液相色谱检测木糖液中葡萄糖含量

建立了木糖母液及发酵液中葡萄糖的柱前衍生化HPLC检测方法。以l-苯基-3-甲基-5-吡唑啉酮（PMP）为柱前衍生化试剂,在ZORBAXEclipseXDB-C18色谱柱上,流动相采用95％A（醋酸盐缓冲液,O．1mol·L-1,pH=5．71）,5％B（乙腈）等比洗脱,检测波长245rim,带宽50nm。目标组分葡萄糖衍生物基线分离无干扰,葡萄糖在2．5-50．0mg·L-1。浓度范围内呈现良好的线性关系,方法检测限为0．2mg·L-1。方法样品前处理简便,灵敏度高,重现性好。     

散乱数据光顺拟合的SOR方法

针对CAGD中散乱数据光顺拟合的一般模型的求解问题，采用罚函数方法处理几何约束。根据最优性条件，将反映曲面光顺性的泛函极小化问题，离散化为曲面参数域网格点上的九点差分格式。得到了关于拟合曲面在网格点上函数值的线性方程组，并证明了该线性方程组的系数矩阵对称正定的性质．保证了采用超松弛法求解线性方程组的收敛性。为了验证所提出方法的有效性，对空间散乱分布的14个数据点，当模型参数取不同值时。分别进行了拟合。试验结果表明，用超松弛法能够简单快速实现散乱数据点的光顺拟合。     

2种养分水平条件下大麦幼苗对重金属铜胁迫的生长响应

以大麦（Hordeum vulgare）幼苗为研究材料,采用10%和35%浓度霍格兰营养液（Hoagland solution）2种养分水平和0、1和10 mg(L^-1 3种铜胁迫水平的正交试验设计,开展为期3周的水培试验,研究养分水平对重金属铜胁迫植物生长的影响。结果表明,与10%霍格兰液相比,35%霍格兰液可提高大麦幼苗在铜胁迫时的生物量积累,增加叶片叶绿素含量以及抗氧化酶活性。但这种缓解作用受铜胁迫水平的影响。在1 mg(L^-1 铜胁迫水平时,提升营养液水平可显著提高植株生物量、叶片叶绿素含量和超氧化物歧化酶（SOD）活性;而在10 mg(L^-1铜胁迫水平时提升营养液水平亦可显著提高叶片过氧化物酶（POD）和谷胱甘肽过氧化物酶（GPX）活性,但对叶绿素含量无影响。此外,铜胁迫对根系生长的抑制作用强于对地上部分的抑制;10%霍格兰液条件下,1 mg(L^-1铜胁迫与无胁迫处理相比可显著增加叶片叶绿素相对含量。提高养分供给是增强大麦耐受铜胁迫能力的一个重要途径。