Physico‐chemical characterization of humic‐metal‐phosphate complexes and their potential application to the manufacture of new types of phosphate‐based fertilizers

The aim of this review is to describe the main physicochemical characteristics of diverse types of humic‐metal‐phosphate acid complexes. The effects of these complexes on phosphorus (P) fixation in soils with different pH values and physicochemical features and on plant phosphorus uptake are also discussed. Humic‐metal‐phosphate complexes have apparent stability constants in the same range as those of metal‐humic complexes, in solutions with diverse pH and ionic‐strength values. Likewise, the molecular‐size distribution of humic‐metal‐phosphate complexes as a function of pH is similar to that of potassium or sodium humates and metal‐humic complexes. Humic‐metal‐phosphate complexes are able to decrease phosphate fixation in soils and increase plant growth and phosphate uptake. Phosphorus fertilizers containing humic‐metal‐phosphate complexes proved to be efficient to improve plant growth and P uptake with respect to conventional fertilizers such as single superphosphate. The values of parameters related to plant phosphorus‐utilization efficiency (PUt E) suggest that the regulation of root acquisition of phosphate from these complexes could involve the interregulation of a system for the optimization of metabolic P utilization in the shoot and another system involving stress responses of roots under phosphorus deficiency.     

抗福美双假单胞菌株的NTG化学诱变及分子探针鉴定

利用微生物的抗药性筛选抗福美双的假单胞菌株Ｔ４６，然后通过亚硝基胍（ＮＴＧ）化学诱变获得了对福美双敏感的三株突变株Ｔ４６Ｎ１０、Ｔ４６Ｎ７和Ｔ４６Ｎ１７。利用这三个突变株作受体，通过基因克隆的方法筛选到了可使三个突变株恢复抗性的克隆，抗性基因分别被定位在７ｋｂ、２．５ｋｂ和２０ｋｂ的ＥｃｏＲⅠ片段上。将这三个克隆分别用（３２）Ｐ标记后制成分子探针，然后分别与三个突变菌株的总ＤＮＡ进行ＤＮＡ－ＤＮＡ分子杂交，结果表明，各突变株均存在与菌株Ｔ４６的抗福美双基因克隆的高度同源性，经结合形态、生理生化等分析后证实这三株突变株均源自于出发菌株Ｔ４６。     

辽宁省凌源市野生苦参资源的现状及开发利用

近年来,随着中草药价格的提升,农村闲散人员采挖野生苦参的现象较多,致使荒山及林地造成严重水土流失,也对野生苦参资源造成毁灭性破坏,保护野生苦参资源,发展人工种植,对提高当地人均收入,切实可行。     

真空平板玻璃传热理论分析及试验

利用辐射-导热耦合模式分析真空平板玻璃的传热途径,通过传热量和传热系数的计算模型,建立真空玻璃的传热控制方程,计算出真空玻璃结构沿高度方向的温度分布和热流通量,并用试验验证了理论计算结果正确性。试验结果表明,真空玻璃传热系数与真空压强成正比,真空度决定真空玻璃绝热性能;真空玻璃外面镀低辐射膜隔绝了较多的辐射热交换,其效果比内面镀膜好。     

灰葡萄孢（Botrytis cinerea）对苯醚甲环唑的敏感性及其对不同杀菌剂的交互抗药性

采用菌丝生长速率法测定了山东省和河北省不同地区的157株灰葡萄孢对苯醚甲环唑的敏感性,结果表明,其中86株野生菌株对苯醚甲环唑的敏感性（EC50值）在0.0135～1.2832μg/mL之间,相差95.05倍,平均值为（0.3958±0.3485）μg/mL,可作为敏感基线。田间已出现对苯醚甲环唑的低抗菌株,占检测总株数的9.5%,未检测到中抗菌株和高抗菌株。通过测定灰葡萄孢不同菌株对苯醚甲环唑、嘧霉胺、腐霉利、多菌灵、乙霉威和异菌脲的敏感性,发现苯醚甲环唑与嘧霉胺、腐霉利、多菌灵、乙霉威和异菌脲之间不存在交互抗性关系。     

鸭绿江松江鲈人工繁育技术研究

采用人工注射催产药物获取受精卵、人工孵化等技术原理,在不同的盐度中进行亲鱼培育、人工催产、人工孵化和苗种培育对比试验研究,重点解决了催产时间、催产药物的选择等技术问题,同时研究出各个时期所需要的最佳盐度。     

山东省机井定量分析

为了给山东省机井建设提供科学的发展依据。通过山东省机井工程的定量分析,指出了机井建设中存在的问题,提出了今后应合理开发利用地下水,严格控制成井质量,保护地下水环境。     

蘑菇渣堆肥做基质对华北落叶松容器苗生长的影响1）

以华北落叶松（ Larix principis-rupprechtii）播种容器苗为研究对象,采用完全随机设计,试验设置6个处理,通过比较苗木形态指标及苗木根系形态结构的差异,研究了添加不同比例的蘑菇渣堆肥对华北落叶松苗木生长的影响。结果表明：基质的密度、pH值、EC值随着蘑菇渣堆肥比例的增加呈现逐渐增大的趋势,总孔隙度、持水孔隙度与对照无显著差异;苗木苗高、地径、生物量及苗木总根长、总根表面积、总根体积随着蘑菇渣堆肥比例增加呈现逐渐减小的趋势;基质中蘑菇渣堆肥比例在0～20％范围内时,苗木形态指标及苗木根系形态结构均与对照无显著差异,基质中蘑菇渣堆肥比例大于30％时,苗木形态指标及苗木根系形态结构与对照出现显著差异,苗木生长受到不利影响。     

施磷水平与冬小麦产量和土壤有效磷含量的关系

[目的]研究施磷水平对冬小麦分蘖成穗、产量、磷素吸收利用的影响及其与土壤有效磷含量的关系,明确维持冬小麦持续高产的最佳土壤有效磷含量及施磷量,为冬小麦高效磷肥管理提供理论依据。[方法]于2018—2021年在河南科技大学农场进行了连续3年小麦田间试验,试验设P₂O₅ 0、90、180和270 kg/hm² 4个磷水平,分别记为P₀、P₉₀、P₁₈₀、P₂₇₀处理,研究了施磷水平对冬小麦分蘖成穗率、干物质积累与分配、产量、磷素吸收与分配及利用效率的影响,并分析了施磷水平、土壤有效磷含量与产量之间的关系。[结果](1)随着施磷水平的提高,冬小麦单位面积最大分蘖数、有效分蘖数和干物质积累量处理间均呈P₂₇₀>P₁₈₀>P₉₀>P₀,而穗粒数、干物质向籽粒中分配率和产量呈先增加后降低的趋势;P₁₈₀处理的冬小麦产量高...     

Dissecting Genetic Basis of Deep Rooting in Dongxiang Wild Rice

Deep rooting is an important trait in rice drought resistance. Genetic resources of deep-rooting varieties are valuable in breeding of water-saving and drought-resistant rice. In the present study, 234 BC₂F₇ backcross introgression lines were derived from a cross of Dongye 80 (an accession of Dongxiang wild rice as the donor parent) and R974 (an indica restorer line as the recurrent parent). A genetic linkage map containing 1 977 bin markers was constructed by ddRADSeq for QTL analysis. Thirty-one QTLs for four root traits (the number of deep roots, the number of shallow roots, the total number of deep roots and the ratio of deep roots) were assessed on six rice chromosomes in two environments (2020 Shanghai and 2021 Hainan). Two of the QTLs, qDR5.1 and qTR5.2, were located on chromosome 5 in a 70-kb interval. They were detected in both environments. qDR5.1 explained 13.35% of the phenotypic variance in 2020 Shanghai and 12.01% of the phenotypic variance in 2021 Hainan. qTR5.2 accounted for 10.88% and 10.93% of the phenotypic variance, respectively. One QTL (qRDR2.2) for the ratio of deep roots was detected on chromosome 2 in a 210-kb interval and accounted for 6.72% of the phenotypic variance in 2020. The positive effects of these three QTLs were all from Dongxiang wild rice. Furthermore, nine and four putative candidate genes were identified in qRDR2.2 and qDR5.1/qTR5.2, respectively. These findings added to our knowledge of the genetic control of root traits in rice. In addition, this study will facilitate the future isolation of candidate genes of the deep-rooting trait and the utilization of Dongxiang wild rice in the improvement of rice drought resistance.