根际氧浓度对番茄幼苗生长发育的影响

为了探究设施园艺作物栽培时适宜的水气环境,采用水培试验,以河南四号和粉珍珠2个栽培番茄品种为研究对象,设置3个氧水平:低氧(0.5~2.0 mg/L)、正常氧(7.0~8.0 mg/L)和饱和氧(14.0~17.0 mg/L)处理,以不通气作为空白对照CK,研究根际不同氧浓度对番茄幼苗植株的形态生长、生物量、根系活力和光合色素的影响。结果表明,随着根际氧浓度的增加,番茄幼苗的长势越好,根系活力增加,但叶绿素含量降低。在处理末期,正常氧处理与饱和氧处理显著提高番茄幼苗的最长根长并增加番茄幼苗的干、鲜质量。其中,在18 d河南四号正常氧和饱和氧处理下总干质量比CK分别增加24.00%和74.86%,而低氧处理比CK降低3.43%;最长根长分别增加67.23%和230.55%,而低氧处理比CK降低1.63%。饱和氧处理下根系更发达健壮,地上部分长势更好,生物量积累最多。因此,在设施园艺栽培管理中,增加营养液中根际氧浓度有利于番茄生物量的积累,进而提高产量。     

陕西关中东部棉花抗旱品种农艺节水综合技术研究

按照生态农业理论和抗旱节水技术要求,对棉花抗旱品种、不同密度、不同基肥N、P的施用量进行田间综合试验,采用正交设计法。3年试验研究结果表明：密度以每公顷种植7.5万株比4.5万株、6万株平均增产671.85kg、483.30kg,增产57.49%和41.36%。品种陕402（早熟）、陕576（中早熟）分别比中棉所19（中熟）增产16.62%和16.17%,具有较强抗旱性。磷酸二铵比尿素增产作用明显,每公顷施150、225kg分别增产11.35%和10.53%。     

番茄营养液深液流无限生长型栽培(Ⅱ)温室综合环境的管理与调控

研究了番茄在营养液深液流无限生长型栽培条件下的温室综合环境 (温度、湿度、光照等 )的调控过程和技术 ,总结了该栽培方式下的环境调控模式。试验结果表明 ,对温室温度、光照、湿度的管理和调控能够满足该栽培条件番茄生长对气候环境的要求 ,能够保证番茄集中座果、集中采收的数量和时间。     

日光温室不同生育期嫁接番茄对根际环境及生长特性的影响

实验以不同砧木嫁接番茄在不同时期根系环境对生长发育的影响研究。结果表明,随着嫁接番茄的生长发育,根际环境也变化。一般情况下,在结果期,放线菌数量较多。植株根系活力大、土壤K、Ca、Mg、Zn含量多、拉秧期细菌数量较大的嫁接番茄,生长势强。     

番茄营养液深液流无限生长型栽培(Ⅳ)营养液动态液位法栽培番茄的试验研究

经过对国内外水培技术中各自独具特色的增氧技术和方法的总结和分析 ,提出了营养液深液流栽培的动态液位增氧法 (DSS)。DSS利用了滴液法、液流法、露根法、湿气根法等几方面增氧的原理和方法。应用动态液位法栽培番茄的试验表明 ,动态液位法可以提高植株的相对生长率、加快叶片和节点的生长、增强根系的活力、促进根系的生长发育。     

烤烟根际土壤特性研究──Ⅰ、烤烟根际与非根际土壤化学性质

通过对贵州主要种烟土壤的研究，结果表明：烤烟根际ｐＨ值、有机质与碳氮比值以及氮、磷、钾的数量与非根际土壤差异明显。烤烟根际ｐＨ值明显下降。有机物质出现积累，氮、磷、钾数量增加，其中有效养分的积累顺序为：Ｋ＞Ｐ＞Ｎ。通过对烤烟根际土壤化学性质的研究，对改良烤烟栽培和施肥制度具有一定的指导意义。     

番茄营养液深液流无限生长型栽培研究之四① 营养液动态液位法栽培番茄的试验研究

经过对国内外水培技术中各自独具特色的增氧技术和方法的总结和分析，提出了营养液深液流栽培的动态液位增氧法（DSS）。DSS利用了滴液法、液流法、露根法、湿气根法等几方面增氧的原理和方法。应用动态液位法栽培番茄的试验表明，动态液位法可以提高植株的相对生长率、加快叶片和节点的生长、增强根系的活力、促进根系的生长发育。     

番茄病毒株的体内酶及根际土壤酶的活性变化

番茄经土壤传染发生病毒病后，植株叶片和根系中的过氧化氢酶与过氧化物酶活性均升高，且叶片中这两种酶活性比根系中的高；其根际土壤中脲酶、转化酶活性降低，多酚氧化酶活性升高，而过氧化氢酶活性略有下降。由此提出：有效地防治病毒病除用药剂喷洒植株外，还应同时对土壤进行处理。     

烤烟根际土壤特性研究：I.烤烟根际与非根际土壤化学性质

通过对贵州主要种烟土壤的研究，结果表明：烤烟根际ｐＨ值、有机质与碳氮比值以及氮、磷、钾的数量与非根际土壤差异明显。烤烟根际ｐＨ值明显下降，有机物质出现积累，氮、磷、钾数量增加，其中有效养分的积累顺序为：Ｋ〉Ｐ〉Ｎ。通过对烤烟根际土壤化学性质的研究，对改良烤烟栽培和施肥制度具有一定的指导意义。     

大青叶根际与非根际解磷细菌分布特征研究初报

以大青叶(Cerasuspseudocerasus)为试材,研究其根际与非根际解磷细菌的数量和种群结构动态变化。结果表明,年生长周期内大青叶根际与非根际解磷细菌的数量在新梢迅速生长期较低,而后逐渐增加,新梢停长期达到峰值,进而又逐渐减少,落叶期最低。大青叶根际与非根际解磷细菌主要以芽孢杆菌属(Bacillus)为主,不同生育期其种类不同,其中新梢停长期根际解磷细菌种类较其他时期复杂,类群最为丰富,共分离到6个菌属。根际与非根际相比解磷细菌种类与数量不同。     

番茄营养液深液流无限生长型栽培营养液的管理与调控

根据北京地区的水质特点和非常规栽培的特殊性,制定了在营养液深液流无限生长型栽培条件下使用的营养液配方。并根据番茄生长发育的不同时期和养分吸收特性,及时调整营养液的组成成分、浓度、酸碱度等,对营养液实行动态管理。栽培试验结果表明,该配方中的各种营养成分（N、P、K、Ca、Mg等）基本可以被番茄均衡地吸收,属于营养均衡的配方。     

地膜覆盖栽培番茄后期早衰的研究

该试验结果表明,地膜覆盖栽培番茄的后期早衰和施肥有关。施肥量多,土壤有效养分和植株的营养状况较好,植株生长发育也较好,小区平均产量最高,达75.2kg,每公倾合4.512万kg,比对照增产16.89％。施肥量低的处理,比对照减产3.76％。     

GA用于脱刺毛番茄种子包衣研究

应用试剂硫酸30秒,即可脱去占番茄种子重量4％的种皮刺毛,同时种子活力及幼苗素质得到提高,且种子表面光滑,利于包衣。脱刺毛后的不同浓度GA包衣试验表明:GA0g/L(空白包衣材料)对种子萌发有一定的阻碍作用,完全抵消了脱刺毛处理的正效应,0.3g/l浓度包衣条件下,GA的促进作用最强,包衣种子活力和幼苗素质明显高于脱刺毛种子和半脱刺毛种子。     

Assessing the impact of increasing carbon dioxide and temperature on crop-weed interactions for tomato and a C3 and C4 weed species

Based on the carboxylation kinetics of the C₃ and C₄ photosynthetic pathway, it is anticipated that C₃ crops may be favored over C₄ weeds as atmospheric CO₂ increases. In the current study, tomato (Lycopersicon esculentum), a C₃ crop species, was grown at ambient (~400 μmol mol⁻¹) and enhanced carbon dioxide (~800 μmol mol⁻¹) with and without two common weeds, lambsquarters (Chenopodium album), a C₃ weed, and redroot pigweed (Amaranthus retroflexus), a C₄ weed, from seedling emergence until mutual shading of crop-weed leaves. Because growth temperature is also likely to change in concert with rising CO₂, the experiment was repeated at day/night temperatures of 21/12 and 26/18 °C. For both day/night temperatures, elevated CO₂ exacerbated weed competition from both the C₃ and C₄ weed species. A model based on relative leaf area following emergence was used to calculate potential crop losses from weeds. This analysis indicated that potential crop losses increased from 33 to 55% and from 32 to 61% at the 21/12 and 26/18 °C day/night temperatures, for ambient and elevated CO₂, respectively. For the current study, reductions in biomass and projected yield of tomato appeared independent of the photosynthetic pathway of the competing weed species. This may be due to inherent variation and overlap in the growth response of C₃ and C₄ species, whether weeds or crops, to increasing CO₂ concentration. Overall, these results suggest that as atmospheric CO₂ and/or temperature increases, other biological interactions, in addition to photosynthetic pathway, deserve additional consideration in predicting competitive outcomes between weeds and crops.     

番茄花药离体培养中低温预处理对小孢子发育的影响

为明确低温预处理对番茄花药离体培养过程中小孢子发育的影响，进行了番茄花药离体培养的低温预处理试验，试验结果表明：离体培养条件下，雄核发育存在三条途径，即B途径、A-V途径和A-G途径，以B途径为主；随着培养时间的增加，小孢子逐渐退化；对番茄花药离体培养进行低温预处理，可在一定程度上延缓番茄小孢子退化，提早雄核发育，并增加参与雄核发育小孢子的比率，但参与B-途径的小孢子比参与A-途径的增加得多。     

A DFT study on formaldehyde reduction in dielectric barrier discharges

Density functional theory (DFT)is used to study the thermodynamics of formaldehyde removal under dielectric barrier discharges (DBD)non-thermal plasma (NTP)conditions at atmospheric pressure and ambient temperature. A calculation model is defined. The calculated reaction relative energies in this work confirm that the DBD plasma is effective for formaldehyde reduction at ambient conditions and at 1 atm. Present calculations indicate that the reactions of HCHO with primary free radicals such as OH·,O·,and H· are all thermodynamically favored. Moreover,theoretical results show that the main routes of O radical generation from O2 are direct dissociation and dissociative attachment-releasing electron, and the main pathways of H· and OH· from H2O are dissociation and attachment. The only thermodynamic obstacle to HO2· formation is 2H2O→H2O2+H2. The reactions of HO2· with other radicals are all thermodynamically favored. Comparative results between the previous investigation and the present work demonstrate that theoretical calculation with DFT can be an efficient and reliable supplement for experimental research.     

Spontaneous outcrossing in tomato depends on cultivar and environment and varies between individual flowers

Knowledge about the degree of spontaneous outcrossing of diverse genotypes is essential for breeding programmes, maintenance breeding, and seed production. For tomato (Lycopersicon esculentum Mill.), very limited scientific evidence for genotypic differences is available and evidence from Europe is scarce. To close this knowledge gap, six cultivars were investigated in three Central European locations as part of the Organic Outdoor Tomato Project. To determine outcrossing rates, the monogenetic “cut‐leaf” trait, which is dominant over the “potato‐leaf” trait, was used as morphological marker. The observed range of outcrossing was 0.0%–5.2%. Outcrossing was significantly influenced by cultivar and environment. The outcrossing rate of individual flowers varied within cultivars ranging from 0% to 37%. The potential of newly opened flowers to accept foreign pollen varied largely with the cultivar. Genotypic differences could partly be linked to flower morphology traits. The potential for recombination between tomato genotypes is generally very low but can be a source for new variation in on‐farm management.     

番茄黄化曲叶病毒病抗性鉴定技术研究

番茄抗病材料的创制及其准确有效的抗性鉴定方法是番茄抗病育种的关键.本文比较研究了烟粉虱侵染接种鉴定技术、分子标记鉴定技术和田间自然接种法对58份番茄抗黄化曲叶病毒病材料的抗性鉴定结果.结果表明:分子标记检测与烟粉虱侵染接种鉴定方法相结合可作为鉴定材料对番茄黄化曲叶病毒病抗性的有效方法;对含有已知基因抗源材料的分离群体,...