乙酰丙酸对叶菜产量、叶绿素和硝态氮的影响

以油麦菜和生菜为试材,通过叶面喷施不同浓度的乙酰丙酸,探索乙酰丙酸对叶菜产量、叶绿素和硝态氮的影响。结果表明,乙酰丙酸对油麦菜产量的影响表现出差异显著,对生菜产量的影响表现出差异不显著。就增产效果而言,油麦菜在喷施稀释800倍乙酰丙酸时增产幅度最大,较对照增产6.46%;生菜在喷施稀释600倍乙酰丙酸时增产幅度最大,较对照增产3.33%。油麦菜不同部位叶绿素含量均是叶尖＞叶中＞叶基。同一部位不同处理间叶绿素含量差异不显著,但与对照相比,各浓度处理下油麦菜叶片不同部位叶绿素含量均有所增加。同时与对照相比,各浓度处理下油麦菜叶片叶绿素含量均有所增加。生菜在喷施稀释600倍乙酰丙酸时叶片叶绿素增加幅度最大,较对照增产6.95%。喷施乙酰丙酸对油麦菜叶片硝态氮含量有增加作用,对生菜叶片硝态氮含量有减少作用。     

抗寒矮化砧对金红苹果生理特性的影响

在立地条件一致的情况下,研究了生长年龄相同条件下的抗寒矮化砧木对金红苹果一些生理特性的影响。结果表明,与普通基砧相比,金红叶片增厚21 0～36 5μm,栅海比明显提高,比叶重增加4 98～6 37mg·g-1,叶绿素含量增加0 249～0 431mg·g-1,Pn值增加1 81～10 86mg·dm-2·h-1,生长期叶片游离氨基酸含量和可溶性糖含量维持较高水平。秋季叶片的内源激素含量差异明显,IAA,GA3,ABA含量分别是对照的61 1%～83 4%,82 3%～87 3%和119 5%～164 5%。     

ALA叶面肥对制种玉米光合特性和产量的影响

以郑单958为材料,采用田间随机区组试验设计,研究了叶面喷施不同浓度5-氨基乙酰丙酸(ALA)叶面肥对制种玉米光合特性及产量的影响。结果表明:ALA叶面肥可以提高玉米叶片叶绿素含量、净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)和产量,降低叶片胞间CO_2浓度(Ci)。其中喷施1500倍ALA液效果最佳,与对照相比,叶绿素含量提高27.61%,净光合速率(Pn)提高31.87%,增产11.62%。因此,ALA叶面肥在玉米制种田中的最佳喷施浓度为1500倍液。     

DPC浸种提高棉苗耐盐性的作用和机理

适当浓度范围 DPC浸种均可提高棉花幼苗耐盐性 ,其中以 1 50 mg· L- 1浓度浸种效果最好。盐胁迫下 1 50 mg·L- 1DPC浸种的幼苗与水浸种相比 ,降低了幼苗对盐分的吸收 ,增强棉苗体内盐分区域化分配 ,促进根系对 K+的吸收和向叶片的选择性运输 ,维持体内的离子平衡 ,降低叶片细胞电解质的外渗 ,改善叶片水分状况和活性氧代谢 ,明显提高叶绿素含量 ,增加干物质积累     

3种植物生长调节剂对花生的光合生理及产量品质的影响

为了探明花生在化学调控作用下的产量、品质变化及与之相关的光合作用机理。比较研究了初花期喷施矮壮素、缩节胺和结荚初期喷施多效唑对花生的化学调控效应。结果表明：3种植物生长调节剂均可矮化植株,增加茎粗、有效分枝数及结果数,提高花生叶片的叶绿素含量和光合速率,并在结荚期降低叶片的蒸腾速率,最终达到提高花生产量和改善花生品质的目的。其中,多效唑对增加花生叶绿素含量、降低蒸腾速率、增加产量和粗蛋白含量的调控效果最好,其产量和蛋白质含量分别比对照增加了9.0%和7.8%;而缩节胺对提高花生的光合速率调控效果最佳,其光合速率比对照增加了25.0%;矮壮素最利于改善花生的亚油酸含量,其亚油酸含量比对照增加了6.4%。综合考虑花生的产量品质和光合生理效应,多效唑对花生的化学调控增产效应最好,其次为缩节胺处理。     

不同种类水稻叶面肥的使用效果分析

为了探明不同种类叶面肥在水稻上的增产效果, 安排在水稻孕穗期及齐穗期喷施水溶性硅钾肥、植物生长调节剂、氨基酸类叶面肥进行试验。试验结果表明,适时喷施叶面肥可以增加绿叶面积,促进光合作用;降低空秕率,增加千粒重。其中喷施硅钾肥效果尤为明显,较对照增产率达 16.8%,增产效果显著。     

农杆菌介导外源基因在棉花中的表达

用 5～ 6d的棉花无菌苗下胚轴切段与农杆菌共培养 ,菌株质粒中 Gus基因为标记基因 ,NPT 基因为选择基因。在含 0 .1 mg· L- 12 ,4- D和 0 .1 mg· L- 1KT的 MS培养基上共培 48h,转移到添加头孢霉素 50 0 mg· L- 1、卡那霉素 50 mg· L- 1MS培养基中诱导和筛选抗性愈伤组织 ,70～ 80 d时 ,进行 Gus检测 ,选择 Gus阳性愈伤组织 ,经体细胞分化生成转基因再生植株     

卷丹快速繁殖的好方法

以卷丹珠芽为外植体进行试管培养,可在很短时间内获得大量优质幼苗.经试验筛选出各培养阶段最适宜的培养基为(1)愈伤组织及芽诱导,MS+6-BA1.2mg·L-1+NAA0.4mg·L-1;(2)继代培养及丛生芽分化,MS+6-BA1.0mg·L+NAA0.2mg·L-1;(3)诱导生根,MS+IBA0.5mg·L.     

四甲基戊二酸对夏玉米光合生产特征的调控效应

为研究四甲基戊二酸(TGA)对夏玉米光合特征和产量的调控效应, 2018、2019年在中国农业科学院新乡试验基地开展大田试验,以中单909 (ZD909)和京农科728 (JNK728)为试验材料,设置5个TGA施用梯度(0、75、150、225和300 g hm~(–2))。结果表明,适宜剂量的TGA处理可提高玉米产量、延缓玉米生育期内功能叶的衰老速率,增强灌浆期的净光合速率,试验条件下TGA的最佳施用量为150 g hm~(–2)。在TGA最佳施用量下, ZD909和JNK728的产量相比对照2年平均分别增加8.7%和11.7%。2个品种玉米生育期内叶绿素含量、可溶性蛋白含量和光合势相比对照平均分别增加14.3%和19.7%、18.7%和22.7%、10.9%和16.9%;而叶片衰老速率相比对照平均降低了55.9%和56.5%;灌浆期的净光合速率相比对照平均分别增加44.0%和58.4%。相关性分析表明,玉米产量与生育期内叶片衰老速率呈显著负相关,而与灌浆期净光合速率呈显著正相关。综上, TGA处理能够提高叶片叶绿素和可溶性蛋白含量,延缓玉米叶片衰老速率,并提高了灌浆期净光合速率,进而实现玉米增产。     

甘蔗应用氨基酸多元叶面肥效应试验

在甘蔗上进行氨基酸多元叶面肥施用效应试验,结果表明：氨基酸多元叶面肥能够促进甘蔗生长,具有增产增糖增效的作用;各处理之间有一定的差异,以氨基酸浸种6小时加苗期喷施3次效果最显著,增产达到112.79t/hm2,比对照增加16.62%,增加收入4096元/hm2。综合分析,建议施用氨基酸多元叶面肥采用浸种与叶片喷施相结合。     

Compensative Effects of Chemical Regulation with Uniconazole on Physiological Damages Caused by Water Deficiency during the Grain Filling Stage of Wheat

Chemical regulation using plant growth regulators has proved to be potentially beneficial in water‐saving agriculture. This experiment was conducted with winter wheat (Triticum aestivum L. cv. ‘Jingdong 6’) to study the effect of chemical regulation on alleviation of water deficit stress during the grain filling stage. Uniconazole, a plant growth regulator, was foliar sprayed at 85 % (adequate irrigation) and 60 % (deficit irrigation) field capacity. Results showed that the distribution of ³H‐H₂O in roots and flag leaf, characteristics of vascular bundle in primary roots and internode below spike, roots activity, transpiration rate and stomatal conductance of flag leaf were negatively affected by deficit irrigation after flowering. Foliar spraying at the early jointing stage with 13.5 gha^?1 uniconazole was able to relieve and compensate for the harmful effects of deficit irrigation. Both the area of vascular bundle in primary roots and internode below the ear were increased by uniconazole, while root viability and their ability to absorb and transport water were increased. In the flag leaf, stomatal conductance was reduced to maintain the transpiration rate and water use efficiency (WUE) measured for a single wheat plant was higher. Uniconazole increased WUE by 25.0 % under adequate and 22 % under deficit irrigations. Under adequate irrigations, the ¹⁴C‐assimilates export rate from flag leaf in 12 h (E_12h) was increased by 65 % and 36 % in early and late filling stages, while under deficit irrigations, the E_12h of uniconazole‐treated plants exceeded that of control plants by 5 % and 34 % respectively. Physiological damages caused by water deficiency during the grain filling stage of wheat was alleviated by foliar spraying with uniconazole.     

烯效唑对花生产量品质影响的研究

以‘花育19’和‘花育23’为试验材料,在花生盛花期叶片喷施烯效唑,研究其对花生产量和品质的影响。结果表明：烯效唑可延缓主茎高的增长,增加主茎直径,烯效唑浓度越大,植株表现越矮壮,以160 mg/L处理矮壮效果最明显;可促进根生长,增加单株根干重和单株果干重,提高根冠比和经济系数,2个品种处理区比对照区的根冠比、经济系数提高了0.8904~1.2015、46.57%~53.46%,产量增加18.09%~69.10%,处理区籽仁粗脂肪含量、蛋白质含量、可溶性糖含量均比对照增加。试验表明：花生盛花期叶片喷施适宜浓度的烯效唑,对花生产量和品质有一定的促进作用。     

GA4+7 plus BA enhances postproduction quality in pot tulips

Previously we reported that postproduction quality of pot ‘Seadov’ tulip (Tulipa gesneriana) was significantly increased by GA₄₊₇ plus BA in a manner dependent on the concentration and stage of flower development at application. In these experiments, we extended the survey to 20 tulip cultivars to further evaluate the effects of GA₄₊₇ plus BA sprays for enhancing postproduction flower and leaf quality. The senescence symptom of the cultivars fell into three categories: wilting, wilting-abscission (abscission shortly after tepal wilting) and abscission (abscission without wilting), with the majority of the cultivars belonging to the wilting and wilting-abscission categories. Pots bearing six plants were sprayed with a range of GA₄₊₇ plus BA concentrations at marketable stage and placed in a simulated consumer environment (SCE). GA₄₊₇ plus BA significantly enhanced individual flower and postproduction longevity, but the effect was dependent upon the senescence category of the cultivar. In general, GA₄₊₇ plus BA increased individual flower and postproduction longevity of wilting-type cultivars at concentrations above 10 mg L^?1, while longevity of wilting-abscission-type cultivars was only enhanced by 50 mg L^?1. Abscission-type cultivars were not affected by any concentrations of GA₄₊₇ plus BA. Regardless of floral senescence category, leaf yellowing was significantly reduced by GA₄₊₇ plus BA sprays in those cultivars showing postproduction leaf yellowing. GA₄₊₇ plus BA did not induce leaf and stem elongation in most cultivars. Only ‘Yellow Baby’, the shortest cultivar, showed elongation of stem and leaf by GA₄₊₇ plus BA at concentrations above 25 mg L^?1. Spray applications of GA₄₊₇ plus BA can be useful to enhance flower and leaf quality in pot tulips.     

烯效唑浸种对谷子植株生长发育的效应

以晋谷21为试验材料,通过盆栽及根管栽培试验,研究了不同浓度烯效唑(15、30、60和120 mg L^-1)浸种处理对谷子地上和地下农艺性状的影响。结果表明,烯效唑浸种对谷子具有明显的控上促下作用,使谷子根系数量、根系活力、根干重、根系总长度及茎粗与分蘖均明显增加,株高明显降低;此外显著降低了前期谷子叶面积,但后期发生逆转,表现出控前促后的效果;还对开花后谷子植株的衰老具有明显的调节作用,可延长根系活力的缓降期,提高衰老期间根系和旗叶中SOD、POD活性,降低根系与旗叶中MDA含量。烯效唑浸种处理可显著增加谷子的成穗数和千粒重,最终显著增加产量,在本试验条件下以30 mg L^-1烯效唑浸种效果最佳。     

多效唑、烯效唑对油菜‘秦优1618’苗期特性和抗寒性的影响

为探索多效唑和烯效唑对油菜新品种‘秦优1618’抗寒性的影响,采用多效唑150 mg/L(C1)、300 mg/L(C2),烯效唑80 mg/L(C3)、160 mg/L(C4)喷施6~7叶期油菜幼苗1次,研究多效唑和烯效唑对幼苗生长调控、生理特性和抗寒性的影响。结果显示：采用多效唑150 mg/L(C1)或烯效唑80 mg/L(C3)处理6~7叶期幼苗,可有效降低苗期薹茎高、茎叶干质量、最大叶长度和宽度,对绿叶数影响不显著,有效提高根茎粗、根长、侧根数、根干质量和根冠比,形成壮苗;同时可增加叶片叶绿素和可溶性糖含量,降低相对电导率,提高叶片净光合速率,降低越冬死亡株率和冻害指数,提高抗寒性。     

水分胁迫下一氧化氮对小麦幼苗根系生长和吸收的影响

以25%聚乙二醇(PEG-6000)模拟干旱, 利用一氧化氮(nitric oxide, NO)供体硝普钠(sodium nitroprusside, SNP) 处理小麦幼苗, 探讨外源NO对水分胁迫下小麦幼苗根系生长和吸收的影响。结果表明, 50 mol L^-1 SNP可增加小麦主根长度及侧根数目, 分别比对照增加11.94%和83.78%。同时, SNP可使水分胁迫下小麦的根系活力提高55.88%, 根系K⁺ 的含量提高42.52%。膜片钳全细胞电流显示, SNP处理可增强小麦根细胞质膜内向K⁺ 电流, 而NO的专一清除剂c-PTIO可以逆转SNP的上述效应。因此认为, 外源NO可通过提高小麦根系活力, 增强根细胞质膜内向K⁺ 通道的活性, 从而促进根细胞对K⁺ 的吸收以适应水分胁迫。     

绿色棉胚珠离体培养体系优化及光照对纤维生长发育的影响

在优化绿色棉离体培养体系的基础上,以绿色棉品种绿絮棉1号、白色棉品种泗棉三号(对照)为材料,比较了光培养和暗培养对鲜胚珠质量、纤维长度、纤维素含量等生理生化指标影响,来探讨光照对绿色棉纤维生长发育的影响。结果表明:花后2 d的绿色棉胚珠较适宜离体培养,其适宜的消毒方式为75%的乙醇10min+0.1%升汞10min;离体培养的适宜激素及其浓度为GA31.0μmol·L-1+IAA 5.0μmol·L-1+ZR 2.5μmol·L-1,3种激素对胚珠鲜质量和纤维伸长影响大小的顺序为ZRIAAGA3。光培养能够抑制纤维的伸长、β-1,3-葡聚糖酶活性和培养前期的纤维蔗糖合成酶活性;但能够促进胚珠的生长、纤维素的合成、纤维PAL活性和培养后期的纤维蔗糖合成酶活性,提高黄酮含量。可见,光照能够对绿色棉纤维生长发育产生一定的影响。     

Impact of a decontamination step with peroxyacetic acid on the shelf-life,sensory quality and nutrient content of grated carrots packed under equilibrium modified atmosphere and stored at 7 °C

Peroxyacetic acid (PAA) is a strong oxidizer and exerts antimicrobial properties. The effect of a decontamination step with 80 and 250 mg L⁻¹ PAA on shelf-life of grated carrots stored under equilibrium modified atmospheric packaging at 7 °C was determined and compared with the shelf-life of unwashed and water-washed carrots. Microbial parameters, including total aerobic plate count, numbers of lactic acid bacteria, Lactobacillae and yeasts, and sensory quality were evaluated. Next to these parameters, atmospheric gas composition, pH and nutrient content were also monitored. The suggested packaging configuration prevented CO₂ accumulation, but at the end of the study anoxic conditions were reached for unwashed carrots and carrots washed with 80 mg L⁻¹ PAA. The microbial shelf-life of water-washed carrots was 4 d based on the yeast count, whereas the flavour was not acceptable after 5 d. The total aerobic plate count and the yeast count determined the shelf-life of carrots treated with 80 mg L⁻¹ PAA on 5 d, whereas the flavour was unacceptable after 7 d. None of the microbial parameters determined the shelf-life of carrots washed with 250 mg L⁻¹ PAA. However, this treatment had already a pronounced adverse effect on the initial sensory quality. Water washing already decreased the content of all individually studied nutrients (−16 to −28%), except for lutein content and the antioxidant capacity. Additional losses after adding PAA on day 0 were found for α-tocopherol and phenols. Regardless of the applied treatment, α- and β-carotene remained stable during storage, whereas ζ-carotene, lutein and α-tocopherol were unstable. The phenol content and the antioxidant capacity of unwashed, water-washed and 80 mg L⁻¹ PAA-treated carrots increased significantly at the end of the storage period, whereas no changes were found in carrots treated with 250 mg L⁻¹ PAA.On the condition that carrots were packed under an adequate EMA, the 80 mg L⁻¹ PAA treatment showed possibilities for extending shelf-life without pronounced effects on nutrient content.     

外源激素对棉花前期生长发育的影响

 以鲁棉28为材料,在大田条件下设置吲哚乙酸（IAA）5 mg·L^-1、10 mg·L^-1,6-苄基腺嘌呤（6-BA）50 mg·L^-1、100 mg·L^-1,赤霉素（GA）20 mg·L^-1、50 mg·L^-1 6个不同浓度水溶液处理,以清水为对照,在苗期至蕾期叶面喷施3次,研究外源激素对棉花前期生长与发育的影响。结果表明,外源激素处理后,棉花主茎纵向生长速度缓于对照,茎粗大于对照。50 mg·L^-1 GA处理的棉株出叶速度、单株叶面积高于对照。6个处理的棉株主茎功能叶叶绿素SPAD值均高于对照。不同浓度IAA、GA处理均促进棉花现蕾,其中20 mg·L^-1 GA处理棉花单株现蕾数多于对照。本试验条件下,苗期叶面喷施IAA 和GA能协调棉花营养与生殖生长,促进蕾的发育,GA处理效果优于IAA处理,其中20 mg·L^-1GA效果最佳,6-BA处理未能促进棉花现蕾。     

Effect of antimicrobial compounds on cut Gerbera flowers: Poor relation between stem bending and numbers of bacteria in the vase water

Gerbera flowers (Gerbera jamesonii) often show stem bending. In four cultivars (Tamara, Liesbeth, Cora, and Mickey), we tested the effects on bending of antimicrobial compounds (chlorine bleach, a slow release chlorine compound, 8-hydroxyquinoline citrate [HQC], silver nitrate, carvacrol and thymol), some combined with sugars. At concentrations used for other cut flowers, inclusion in the vase solution of several of the antimicrobial compounds delayed bending, had no effect, or hastened bending. Hastening of bending was found at higher concentrations. It was accompanied with visible damage on the stem ends. Results with HQC indicated high toxicity as it did not delay bending at any of the concentration tested (100–400 mg L⁻¹). At 200 mg L⁻¹ HQC induced growth of bacteria that were not found in the controls. The number of bacteria in the vase water showed a low correlation with bending. Visible toxicity on the stem surface was often associated with a high bacteria count. However, at relatively high concentrations of the antimicrobial compounds stem bending was associated with a low count. This indicated an effect other than bacteria. Water uptake was low in stems that bent early. It is hypothesized that material from dead stem cells resulted in a xylem blockage which led to early bending. Sucrose at 15 g L⁻¹ in combination with an antimicrobial compound (slow release chlorine, HQC) resulted in the absence of stem damage and produced much less bending than the same concentration of the antimicrobial compounds alone. Sucrose apparently counteracted the toxic effects of the antimicrobial chemicals.