猪粪对露地黄瓜产量及土壤培肥效果的影响

为给露地黄瓜生产及土壤培肥提供参考,以猪粪为变量因素,采用随机区组设计,对露地黄瓜产量和土壤养分的影响进行研究。结果表明:在露地黄瓜的生产中,1.50kg.m-2的猪粪施用量为最佳施用量,不宜过多,另通过施入猪粪还可以增加土壤中速效氮、速效磷、速效钾和有机质的含量,且随着施用量的增加而增加,增强土壤肥力。     

黄瓜全雌性基因连锁的AFLP和SCAR分子标记

 本研究以全雌品种‘戴多星’自交系和弱雌品种‘北京截头’自交系为双亲杂交获得F₁ ,然后得到F₂ 性型分离群体, 利用分离群体分组分析法(Bulked Segregant Analysis, BSA) 构建全雌和弱雌两个基因池, 筛选了64对AFLP选择性引物EcoR I-NN +Mse I-NNN组合, 发现EcoR I-TG +Mse I-CAC引物组合在全雌基因池中扩增出一条分子量为234 bp的特异带。经F₂ 代单株验证, 该特异条带能在全雌单株中稳定出现。以MAP MAKER (Version 310) 软件分析, 该标记与全雌性位点的连锁距离在617 cM。命名该连锁标记为TG/CAC₂₃₄。将该特异条带回收、克隆、测序, 设计特异SCAR引物, 再对F₂ 代单株基因组DNA进行扩增, 仅在全雌单株中扩增出1条分子量为166 bp 的特异带, 表明已成功地将与黄瓜全雌性连锁的AFLP标记转化为操作简便、表现稳定的SCAR标记, 该标记命名为SA₁₆₆。     

几种微生物菌剂处理下连作黄瓜的生长分析

采用盆栽法研究了4种微生物菌剂(连茬王、护根宝、金宝贝、木霉菌肥)处理对连作黄瓜生长的影响。结果表明:4种菌剂处理下连作黄瓜的各项生长指标均较对照有所提高;木霉菌肥和护根宝处理明显提高了连作黄瓜的相对生长率、净同化率、叶面积指数、群体光合势及群体生长率;连茬王处理对黄瓜叶重比及叶片厚度具有明显的促进效应。综合各菌剂对连作黄瓜地上部生长的改善效果,依次为木霉菌肥护根宝连茬王金宝贝。     

Effect of high rates of zinc on several crops grown on an irrigated plainfield sand

Abstract

A field experiment was conducted to determine whether Zn applied for pathogen control could accumulate to a level which would be toxic to snapbeans, cucumbers, or corn. Zinc sulfate (ZnSO₄) was applied at rates varying from 0 to 363 kg Zn/ha on a Flainfield loamy sand to approximate 3, 9, 27 and 81 years of fungicidal treatment.

Even at the high rate of Zn, yields of snapbeans, cucumbers, or corn generally were not reduced. As rates of applied Zn increased, there was a corresponding increase in the level of Zn in the leaf tissue of all crops grown. At the high Zn rate, snapbean and cucumber leaf tissue accumulated over 350 ppm Zn. Available soil Zn was extracted with 0.1N HCl, EDTA, or DTPA. Highly significant correlations were observed between the Zn removed by each extractant and plant tissue Zn, thus, indicating that the various extractants were equally effective in predicting Zn uptake.

Very little downward movement of Zn was observed. Two and one‐half years after application, the Zn had leached to a depth of only 30 cm in the soil profile at the higher Zn rates.

These data indicate that application of Zn‐containing fungicides and bactericides should not cause a Zn toxicity problem on the Plainfield sand in the foreseeable future.     

西红花抗肿瘤作用的研究进展

癌症明显影响人类的平均寿命和生活质量,而从蔬菜、草药和香料中提取的天然物质可能有助于预防或治疗多种癌症。西红花具有多种活性成分,具有明显的抗肿瘤潜力,民间中医已将其广泛用于治疗很多疾病。该文通过查阅知网、PubMed和SciFinder中相关文献和资料,获得西红花试验数据,并进行归纳总结,着重介绍了西红花及其主要成分,并对国内外大量的体内、体外试验的研究进展进行综述,发现藏红花具有清除自由基和抗肿瘤活性,并在体外和体内模型中均具有明显的抗肿瘤作用。基于当前数据表明,西红花可被视为有潜力的候选临床抗癌药物。     

萝卜与芥菜远缘杂交新品种的选育研究

以萝卜不育系为母本,雪里蕻、大头菜和多裂叶芥为父本,在温室通过蜜蜂进行远缘杂交,并获得杂交种。经过田间种植淘汰掉假杂种,获得一株叶形明显变异的品种,对其自交,其分离成7个类型品系。选取较稳定的"萝芥4号"品系观察了其生长形态、下扎趋势以及根系分布特性,分析了早期生长过程中品种间的相似性,同时针对"萝芥4号"及对照品种进行营养成分分析。采用"武A"雄性不育系与"萝芥4号"配制杂交组合,获得叶片性状遗传稳定、肉质根杂交优势明显的组合,该组合十分适合腌制加工。     

绿肥翻压与氮肥减施对水稻产量、品质及土壤肥力的影响

为探明绿肥山黧豆种植翻压下减量施用化学氮肥的潜力,通过3年田间定位试验,设置冬闲+100% N肥（常规施肥,CK）、山黧豆+60% N肥（GM+N60）、山黧豆+70% N肥（GM+N70）、山黧豆+80% N肥（GM+N80）、山黧豆+不施肥（GM）和冬闲+不施肥（NF）共6个处理,研究不同处理对水稻产量、品质及土壤肥力的影响。结果表明,与CK相比,山黧豆与氮肥减量配施能提高水稻产量,GM+N70和GM+N80处理显著提高水稻产量,分别增产13.84%和7.25%;且能提高稻米糙米率、精米率、整精米率和蛋白质含量,降低垩白度及垩白粒率和直链淀粉含量。其中,GM+N70处理的整精米率最高,为78.02%,垩白粒率最低,为18.11%;GM+N80处理的直链淀粉含量最低,为14.26%。山黧豆与氮肥减量配施能明显提高土壤有机质、全氮、碱解氮和速效钾含量,对土壤有效磷含量无显著影响。综上,种植翻压山黧豆与氮肥减量20%~30%配施有利于提高水稻产量、品质及土壤肥力,为构建四川稻区山黧豆种植翻压还田后科学施用氮肥提供理论依据。     

不同处理对黄瓜种子萌发的影响

研究不同酸碱性溶液浸泡、不同光照变化、不同低温冷冻、不同温度水浴和不同时间超声波处理对‘伯乐一号’黄瓜种子萌发的影响。采用双层滤纸培养法对处理后的种子进行培养,观察记录种子的发芽势、发芽率和发芽指数,并对数据进行统计分析。实验显示,pH 9碱性溶液浸泡、持续黑暗处理、 48 h冷冻处理、30℃水浴处理和20 min超声波处理均可以提高‘伯乐一号’黄瓜种子发芽率;其中以48 h冷冻处理的‘伯乐一号’黄瓜种子发芽率最高,达到89.33%。总结出‘伯乐一号’黄瓜种子萌发的最适处理方法,对生产实践中有效促进其种子萌发及人工栽培具有重要的指导意义。     

Synthetic Iron Chelates as Substrates of Root Ferric Chelate Reductase in Green Stressed Cucumber Plants

This work studied the behavior of different iron (Fe)-chelates as substrates of ferric chelate reductase (FCR) and their ability as Fe suppliers for mildly chlorotic plants. FCR activity and Fe concentration in xylem sap were determined in green stressed cucumber plants with different stress levels using different synthetic chelates as substrates. Both reduction and Fe concentration in the xylem sap were higher for the less-stable Fe chelates, except for Fe-EDTA, which presented a relatively low Fe concentration in sap. It was concluded that a high stability of the chelate in the nutrient solution reduces the Fe reduction, but other factors, such as the complexation of the Fe(II) by the chelating agents, should be considered when the complete process of Fe uptake is studied. The use of both indexes together, i.e., FCR determination and xylem sap concentration, is useful for understanding the Fe uptake from different Fe chelates.     

CO2浓度升高与增施钾肥对土壤化学性质的影响

采用土培和开顶箱法,研究了大气CO_2浓度升高与增施K肥共同作用对土壤化学性质的影响.结果表明,土壤中N、P的含量在高CO_2浓度和高K肥水平下下降,K的含量随K肥用量增加而增加.高K(200、300 mg/kg)处理和高浓度CO_2下温室次生盐渍化土壤中的NO_3~(-)、PO_4~(3-)、Ca~(2+)、Mg~(2+) 含量也显著降低.因此,在未来CO_2浓度升高的环境中,更多的K肥供应能促进作物对此生盐渍化土壤中养分的吸收,降低此生盐渍化土壤中盐分的积累.