喷施不同形态锰肥对叶用油菜镉累积及亚细胞分布的影响

为探明喷施锰肥对叶用油菜累积镉的调控作用,采用盆栽试验,研究喷施不同浓度的MnSO_4、Mn(CH_3COO)_2和EDTA·Na_2Mn对两种叶用油菜(Cd低积累品种华骏和普通品种寒绿)生物量以及Cd和Mn含量的影响,并通过分析Cd在叶用油菜体内的吸收转运规律以及亚细胞分布特征揭示其作用机理。结果表明,喷施3种形态Mn肥对Cd低积累叶用油菜地上部和根部生物量无显著影响,喷施高浓度Mn(CH_3COO)_2和EDTA·Na_2Mn显著降低普通叶用油菜地上部生物量。喷施MnSO_4和Mn(CH_3COO)_2处理降低叶用油菜Cd含量、提高Mn含量的效果明显优于EDTA·Na_2Mn处理,其中,0.4 g·L~(-1)Mn的MnSO_4和0.2 g·L~(-1)Mn的Mn(CH_3COO)_2处理降低Cd低积累叶用油菜地上部Cd含量的效果最佳,可使其分别降低29.2%和31.0%。喷施Mn肥显著降低叶用油菜总Cd累积量,使Cd转运系数显著升高,叶用油菜地上部Cd含量与总Cd累积量呈极显著的相关性(P0.01),而与Cd转运系数则无显著相关性。Cd和Mn在叶用油菜地上部主要分布在细胞可溶组分中,其次为细胞壁。喷施Mn肥后,Cd和Mn在细胞壁组分的分配比例降低,在可溶组分的分配比例升高。总之,喷施0.4 g·L~(-1)Mn的MnSO_4和0.2 g·L~(-1)Mn的Mn(CH_3COO)_2可以显著降低低积累叶用油菜地上部Cd含量,提高其Mn含量,同时不影响叶用油菜生长,是保障Cd低积累叶用油菜安全优质生产的较好措施。     

高磷土壤施用磷肥对小白菜和苋菜产量及肥料利用率的影响

采用土培试验,在高磷(O lsen-P为117 mg/kg土)条件下种植小白菜和苋菜,施用0 mg/kg,50 mg/kg,100 mg/kg,200 mg/kg,400 mg/kg磷肥(P2O5),探讨高磷土壤施用磷肥对小白菜和苋菜产量及肥料利用率的影响。结果表明:与不施用磷肥相比,在高磷土壤上施用50 mg/kg,100 mg/kg,200 mg/kg磷肥(P2O5)并未提高小白菜和苋菜产量,施用400 mg/kg磷肥(P2O5)对小白菜有显著增产效果,但对苋菜没有增产效果;随磷肥施用量的增加,小白菜和苋菜地上部磷积累量都有增加的趋势,施用400 mg/kg磷肥(P2O5)处理小白菜和苋菜地上部磷积累量均最高,且分别显著高于对应的不施用磷肥处理;小白菜各施磷肥处理间磷肥利用率均没有显著差异,施用50 mg/kg磷肥(P2O5)处理的磷肥利用率为6.70%,小白菜其它施磷肥处理和苋菜的所有施磷肥处理磷肥利用率均低于5.00%;随着磷肥施用量的增加,小白菜体内磷利用效率下降;与不施磷肥处理相比,各施磷肥处理苋菜体内磷素利用效率没有下降。     

Effects of different LEDs light spectrum on the growth,leaf anatomy,and chloroplast ultrastructure of potato plantlets in vitro and minituber production after transplanting in the greenhouse

Light spectrum plays an important role in regulating the growth and development of in vitro cultured potato(Solanum tuberosum L.) plantlets. The status of potato plantlets at the end of in vitro stage influences the minituber production after transplanting. With 100 μmol m~(-2)s~(-1) total photosynthetic photon flux density(PPFD), a light spectrum study of 100% red light emitting diodes(LEDs) light spectrum(RR), 100% blue LEDs light spectrum(BB), 65% red+35% blue LEDs light spectrum(RB), and 45% red+35% blue+20% green LEDs light spectrum(RBG) providing illumination at the in vitro cultured stage of potato plantlets for 4 weeks using fluorescent lamp as control(CK) was performed to investigate the effects of LEDs light spectrum on the growth, leaf anatomy, and chloroplast ultrastructure of potato plantlets in vitro as well as the minituber yield after 2 months transplanting in the greenhouse. Compared to CK, RB and RBG promoted the growth of potato plantlets in vitro with increased stem diameter, plantlet fresh weight, plantlet dry weight, and health index. Furthermore, BB induced the greatest stem diameter as well as the highest health index in potato plantlets in vitro. Root activity, soluble protein, and free amino acid were also significantly enhanced by BB, whereas carbohydrates were improved by RR. In addition, thickness of leaf, palisade parenchyma and spongy parenchyma was significantly increased by BB and RBG. Chloroplasts under BB and RBG showed well-developed grana thylakoid and stroma thylakoid. Unexpectedly, distinct upper epidermis with greatest thickness was induced and palisade parenchyma and spongy parenchyma were arranged neatly in RR. After transplanting in the greenhouse for 2 months, potato plantlets in vitro from BB, RB, and RBG produced high percentage of large size tuber. BB improved fresh and dry weights of the biggest tuber but decreased tuber number per plantlet. In addition, RBG increased tuber number as well as tuber fresh and dry weight slightly. Our results suggested monochromatic blue LEDs as well as combined red, blue or/and green LEDs light spectrum were superior to fluorescent lamp spectrum in micro-propagation of potato plantlets. Therefore, the application of RBG was suitable; BB and RB could be used as alternatives.     

水肥耦合对海泡石钝化修复镉污染土壤效率的影响

为探讨水肥耦合对海泡石钝化修复镉(Cd)污染土壤效率的影响,采用盆栽试验,以油菜为供试植物,研究了两种水分条件下施用质量分数为0.5%、1.0%和2.0%的蚯蚓粪肥对钝化土壤中有效态Cd含量、油菜根部和可食部分Cd含量的影响。结果表明,土壤水分含量为60%～65%时,施用海泡石能够显著降低土壤中有效态Cd的含量,进一步施用蚯蚓粪肥土壤中有效态Cd的含量为单一海泡石处理的2.24～2.72倍,但是油菜可食部分Cd含量与单一海泡石处理相比变化不显著(P0.05);土壤水分含量为100%时,在钝化修复下施用0.5%、1.0%和2.0%的蚯蚓粪肥,土壤中有效态Cd的含量为单一海泡石处理的1.11、1.17倍和1.26倍,施用0.5%和2.0%蚯蚓粪肥,油菜可食部分Cd含量与单一海泡石处理相比降低了55.9%和56.8%。因此土壤水分含量为60%～65%时,在海泡石钝化修复下施用蚯蚓粪肥,水肥耦合对钝化效应的影响较小;土壤水分含量为100%时,施用0.5%或2.0%蚯蚓粪肥,水肥耦合能够强化海泡石的钝化效应,进一步降低油菜对Cd的吸收和累积。     

补光对日光温室越冬番茄生长及产量品质的影响

以普通荧光灯为对照,采用不同光质荧光灯(红,蓝,红蓝1∶1)对日光温室内番茄进行定时补光(6:30—8:30,16:00—18:00;光照强度2 000 lx),研究不同光质补光对番茄生长、产量及品质的影响。结果表明,与对照相比,补照红光能够促进番茄植株生长;补照红光和红蓝混合光能提高番茄产量,且补照红光的增产效果最好,产量增加22.4%;可溶性糖含量以红光处理最高,可溶性蛋白、Vc和可滴定酸含量以蓝光处理最高,果实番茄红素含量在红光与红蓝混合光照射下均明显增加。综合评价,补照红光有利于促进番茄生长,提高产量和品质。     

Overhead supplemental far-red light stimulates tomato growth under intra-canopy lighting with LEDs

Far-red(FR) light regulates phytochrome-mediated morphological and physiological plant responses.This study aims to investigate how greenhouse tomato morphology and production response to different durations of FR light during daytime and at the end of day(EOD).High-wire tomato plants were grown under intra-canopy lighting consisting of red(peak wavelength at 640 nm) and blue(peak wavelength at 450 nm) light-emitting diodes(LEDs) with photosynthetic photon flux density(PPFD) of 144 μmol m–2 s–1 at 10 cm away from the lamps,and combined with overhead supplemental FR light(peak wavelength at 735 nm) with PPFD of 43 μmol m–2 s–1 at 20 cm below the lamps.Plants were exposed to three durations of FR supplemental lighting including: 06:00–18:00(FR12),18:00–19:30(EOD-FR1.5),18:00–18:30(EOD-FR0.5),and control that without supplemental FR light.The results showed that supplemental FR light significantly stimulated stem elongation thereby resulting in longer plants compared with the control.Moreover,FR light altered leaf morphology toward higher leaf length/width ratio and larger leaf area.The altered plant architecture in FR supplemented plants led to a more homogeneous light distribution inside the canopy.Total plant biomass was increased by 9–16% under supplemental FR light in comparison with control,which led to 7–12% increase in ripe fruit yield.Soluble sugar content of the ripe tomato fruit was slightly decreased by longer exposure of the plants to FR light.Dry matter partitioning to different plant organs were not substantially affected by the FR light treatments.No significant differences were observed among the three FR light treatments in plant morphology as well as yield and biomass production.We conclude that under intra-canopy lighting,overhead supplemental FR light stimulates tomato growth and production.And supplementary of EOD-FR0.5 is more favorable,as it consumes less electricity but induces similar effects on plant morphology and yield.     

光强对菘蓝生长、化学成分及抗氧化活性的影响

  目的  探究光强对大青叶基原植物菘蓝Isatis indigotica生长、药材大青叶化学成分及抗氧化活性的影响,为大青叶基原植物菘蓝的人工栽培提供参考。  方法  在100%全光照、60%全光照、20%全光照下种植菘蓝,观测菘蓝生长旺盛期叶片生长情况,同时测定大青叶靛蓝、靛玉红、总黄酮、总多糖、总游离氨基酸等化学成分质量分数和抗氧化活性。  结果  菘蓝叶片生长与光强呈正相关,100%全光照组的菘蓝株高、叶长、叶宽、叶片数、叶面积均为最高;大青叶靛蓝、总黄酮、总多糖质量分数均随着光强的降低而降低,且各组间差异显著(P＜0.05);靛玉红质量分数随光强的增加呈先升高后降低的趋势,60%全光照组显著高于其他处理(P＜0.05),但100%全光照组与20%全光照组间差异不显著;总游离氨基酸质量分数随着光强的降低而升高。抗氧化活性与光强呈正相关,20%全光照组的1,1-二苯基-2-三硝基苯肼(DPPH)自由基半清除率(I_C50)显著高于60%全光照组和100%全光照组(P＜0.05)。  结论  100%全光照下大青叶药材产量最高,且内在品质最好,较60%和20%全光照更适合栽培。表8参39     

不同光照下土壤水分胁迫对长苞铁杉幼苗的作用

于2004—2005年研究了在不同光照下（100％、50％、25％、10％全日照）水分胁迫（土壤含水量30％、25％、20％、15％）处理30 d后的长苞铁杉幼苗存活率、叶片光合色素含量及比例、MDA含量、SOD活性、POD活性和Pro含量的变化. 结果表明:在光照与土壤干旱协同作用对幼苗的影响方面,强光照（100%全日照）加重了干旱对幼苗的伤害,遮阴可以降低不利因素的影响;在光照与土壤过湿协同作用对幼苗的影响方面,强光（100全日照）和弱光照（10%全日照）加重了土壤水分过多引起的伤害,中等强度光照（50％和25％全光照）可以降低不利因素的影响;在50％和25％全日照条件下,长苞铁杉幼苗对土壤水分过多和干旱胁迫的忍耐能力较强.      

植物补光技术对西安地区日光温室番茄生长的影响

为探讨植物补光灯在设施作物栽培上的应用效果，对比日光温室番茄在补光和不补光2种条件下的生长情况，探究补光对西安地区日光温室番茄生长的影响。结果表明，补光后番茄株高、茎粗、叶片数、单株花数均较不补光高。随着补光时间的延长，补光后番茄株高、茎粗、叶片数、单株花数与不补光的差异增加。补光后番茄产量和产值均较不补光高，经济效益显著。利用植物补光灯补光对番茄植株营养生长及产量增加均有促进作用，说明植物补光灯在西安地区设施蔬菜种植中具有一定的推广意义。     

光质对立体浮盘培育烟苗叶片光合特性及根系生长的影响

为研究光质对立体浮盘培育烟苗叶绿体色素、光合响应和根系发育的影响,试验设置白光(对照)、红光、蓝光和LED光4个处理。结果表明:与其他光质比较,蓝光光质下烟苗叶绿素a含量显著(P0.05)提高16.13%~28.57%、叶绿素b显著提高30.00%~36.84%,此外,类胡萝卜素含量比红光光质下显著提高18.18%;不同光质条件下烟苗叶片最大净光合速率(Pmax)的大小关系为蓝光白光LED光红光,且蓝光光质下烟苗光饱和点最高;红蓝光质下,烟苗根系长度、根系表面积、根系平均直径和根系体积均显著(P0.05)增加,以蓝光下烟苗根系发育最好,其烟苗4叶1心时根系长度达98.11cm、根系表面积22.78cm2、根系平均直径0.74mm和根系体积0.42cm3。本研究结果表明,采用蓝光光质更适用于烤烟立体育苗,有利于培育壮苗。     

硝酸态氮及亚硝酸态氮在不同pH条件下对蔬菜生长的影响

以番茄、黄瓜、甘蓝和小白菜为材料,用营养液栽培法研究了不同硝酸态氮(NO_3-N)与亚硝酸态氮(NO_2-N)配比(NO_3-N:NO_2-N分别为12:0,8:4,4:8,0:12mM),不同pH值(pH7、6、5三组),对蔬菜生长和NO_3-N,NO_2-N、游离氨基酸累积的影响。结果表明,这四种蔬菜明显地分为两类:番茄、小白菜易感受NO_2-N的危害,并且有随溶液中pH值的下降而受害加剧的趋势;而黄瓜和甘蓝则对NO_2-N具有较强的耐受性。供试植株内NO_3-N与NO_2-N的累积量,随营养液中硝酸盐及亚硝酸盐的浓度增大而增加。叶莱较果菜易于累积NO_3-N与NO_2-N。大量施用亚硝酸态氮肥,会导致蔬菜内个别氨基酸的异常积累,引起氮素代谢的紊乱。番茄积累最多的是苏氨酸,小白菜为天门冬氨酸。     

光质对狗蔷薇类原球茎发生和植株再生的影响

为探讨光照对狗蔷薇类原球茎的发生和植株再生的影响,采用发光二极管(LED)调制获取不同光谱能量分布的光质配比(纯红光、偏红光(3∶1)、等比光(1∶1)、偏蓝光(1∶3)、纯蓝光),以荧光灯和黑暗作对照,结果表明:偏蓝光条件下狗蔷薇类原球茎的发生率最高,达64%;蓝光、偏红光以及荧光灯下PLBs发生率30%左右,黑暗情况下仅14%。在偏蓝光条件下平均每外植体产生的类原球茎量是其他光质下的2倍。PLBs萌发率在纯红光条件下达到30%,在红蓝混合光下达20%左右,纯蓝光下仅为17%。但在PLBs分化和萌发过程中,含红光条件下的PLBs萌发后更易形成假珠芽,最高达12%,蓝光下仅形成畸形苗。说明不同光质组合对PLBs发育的不同阶段产生不同的影响,偏蓝光有利于狗蔷薇PLBs的发生,红光有利于PLBs的分化和萌发,在含红光的光照下容易诱导出假珠芽。     

外源褪黑素对低温弱光胁迫下辣椒叶绿素荧光和抗氧化系统的影响

以陇椒10号为试验材料,待辣椒幼苗长至6片真叶时,叶面喷施不同浓度褪黑素(MT)溶液0(T1)、50(T2)、100(T3)、150(T4)、200(T5)和250(T6)μmol·L^-1,研究不同浓度褪黑素对辣椒幼苗低温弱光胁迫条件下叶绿素含量、叶绿素荧光参数、相对电导率、可溶性糖、丙二醛(MDA)含量以及抗氧化酶活性的影响。结果表明:在低温弱光胁迫下(15 ℃/5 ℃,100 μmol·m^-2·s^-1)处理7 d后,与T1相比,外源喷施 100 μmol·L^-1的褪黑素溶液(T3)后总叶绿素含量和可溶性糖含量分别提高了25.72%、52.88%,实际光化学效率Y(Ⅱ)、光化学猝灭系数qP、光化学猝灭qL分别显著增加了43.79%、36.99%和33.88%,超氧化物歧化酶(SOD)、超过氧化氢酶(CAT)活性显著提高了66.31%、56.65%,超氧阴离子含量、相对电导率分别显著降低了48.40%、17.54%。综上所述,叶面喷施褪黑素能通过提高低温弱光胁迫下辣椒叶片叶绿素含量、叶绿素荧光特性及抗氧化能力,并且通过提高可溶性糖含量来增加植株的抗逆性,以100 μmol·L^-1的褪黑素溶液处理效果最好。     

补充光照对温室冬茬黄瓜幼苗生长及生理特性的影响

对温室冬茬黄瓜幼苗设置3种不同光照强度,研究黄瓜苗期补充光照对保护地品种津春三号和露地品种龙杂黄七号的外观形态、叶绿素含量、可溶性糖和可溶性蛋白含量及几种膜保护性酶活性的影响。结果表明,补光处理后,黄瓜幼苗长势良好,叶片的叶绿素含量升高,可溶性糖含量、可溶性蛋白含量升高,POD活性降低,CAT活性升高,MDA含量降低。两品种黄瓜各生理特性变化规律基本一致,但补光对两品种的影响程度不同。     

光质对杉木幼苗叶片光合作用的影响

为探明4种光质处理对杉木幼苗的光合参数的影响,以1年生的优良无性系020扦插苗为试验材料,设置4种光质,8个梯度的光强;通过室内光质培育,研究杉木幼苗的光合速率（P_n）、气孔导度（G_s）、胞间CO₂浓度（C_i）、蒸腾速率（T_r）、水分利用效率（C_WUE）等参数,并对各种光质与光强数据进行拟合分析,建立拟合模型。结果表明,在弱光环境下,蓝光和红:蓝(1:1)对杉木幼苗的光合参数的影响显著,而在强光下,红光的作用显著。红光处理下的杉木幼苗的光合速率（P_n）、气孔导度（G_s）、水分利用效率（C_WUE）等方面与其他光质处理有差异,而在胞间CO₂浓度（C_i）、蒸腾速率（T_r）方面虽然略低于蓝光,但蓝光、红光和红:蓝(1:1)3种光质处理结果的差异性不显著。在光强与光质的拟合方面,气孔导度（G_s）、胞间CO₂浓度（C_i）和蒸腾速率（T_r）的拟合性较好。因此,一定程度上的红:蓝(1:1)光对杉木的光合参数有促进作用。     

Effects of Allicin on Lipid Metabolism and Antioxidant Activity in Chickens

To investigate the effects of allicin on chickens＇ lipid and antioxidant performance, Hy-laying hens＇ diets were replenished with 0 mg · kg-1, 50 mg · kg-1, 100 mg · kg-1, and 150 mg · kg-1 allicin for 42 days, respectively. The alanine aminotransferase（ALT）, aspartate aminotransferase（AST）, triglyceride（TG）, total cholesterol（TCHO）, high density lipoprotein（HDL）, and low density lipoprotein（LDL） levels were measured in chicken serum. Superoxide dismutase（SOD）, glutathione peroxidase（GSH-Px） activity and malondialdehyde（MDA） levels were measured in chicken serum and liver tissue homogenate. The results showed that the supplement dose of allicin tested did not significantly change the activity of ALT or AST（P〉0.05）; TG and CHOL levels decreased with the increase of allicin additive doses, and the difference between treatment groups and CG was significant（P〈0.05）, and there was the best effect with 100 mg · kg-1; allicin significantly reduced the content of MDA, and increased SOD and GSH-Px activities compared with CG（P〈0.05）, and 100 mg · kg-1 of allicin resulted in the strongest SOD and GSH-Px activity. The antioxidant function test results of liver tissue homogenate were consistant with that of serum. Our findings indicated that allicin could enhance antioxidant capacity and reduce blood lipid level in chickens and 100 mg · kg-1 was the optimal amount of allicin additives.     

不同光质对草莓果实花青苷、酚类物质及类黄酮物质的影响

研究了相同光强不同光质对‘丰香’草莓果实花青苷、酚类物质及类黄酮物质含量的动态变化。结果表明:在不同光膜条件下,草莓果实花青苷含量从大到小依次为:黄膜>绿膜>中性膜>蓝膜>红膜,与远红光/红光比例相关;而酚类物质的含量变化则是蓝膜>绿膜>黄膜>中性膜>红膜,与红光/远红光的比例成负相关;类黄酮物质含量与酚类物质含量变化趋势一致。     

不同残膜含量对淡灰钙土水分入渗过程的影响

为探讨不同残膜含量对土壤入渗性能的影响,以银川平原淡灰钙土为研究对象,设置5组不同残膜量：0（T0）、100（T1）、200（T2）、400（T3）、800 kg·hm^-2（T4）,利用一维垂直定水头入渗法,观测湿润锋运移规律和水分入渗过程,并利用4种入渗模型拟合土壤入渗过程,分析其适用性。结果表明,随残膜含量递增,在同一入渗历时内累积入渗量逐渐减小。当入渗时间为390 min时,与T0相比,T1~T4处理的累积入渗量分别减少4.7%、5.8%、6.3%、11%。在入渗同等时间内,残膜量越高其湿润锋运移距离越短。当湿润锋在土柱完成运移时,T0~T4处理分别耗时390、420、510、600、660 min,即随残膜含量的升高入渗时间延长。T0~T4稳定入渗速率分别为0.27、0.24、0.21、0.19、0.16 mm·min^-1,入渗率随残膜含量的升高而降低。入渗模型拟合的R²大小依次为通用经验模型 > Kostiakov模型 > Philip模型 > Horton模型,通用经验模型适合描述含残膜土壤的水分入渗过程。研究表明残膜对淡灰钙土水分入渗存在抑制作用,其影响程度随残膜量增加而增大。     

Exogenous GSH protects tomatoes against salt stress by modulating photosystem Ⅱ efficiency,absorbed light allocation and H_2O_2-scavenging system in chloroplasts

The effects of exogenous GSH(reduced glutathione)on photosynthetic characteristics,photosystem Ⅱ efficiency,absorbed light energy allocation and the H_2O_2-scavenging system in chloroplasts of salt-stressed tomato(Solanum lycopersicum L.)seedlings were studied using hydroponic experiments in a greenhouse.Application of exogenous GSH ameliorated saline-induced growth inhibition,the disturbed balance of Na~+ and Cl~- ions and Na~+/K~+ ratios,and the reduction of the net photosynthetic rate(P_n).GSH also increased the maximal photochemical efficiency of PSⅡ(F_v/F_m),the electron transport rate(ETR),the photochemical quenching coefficient(q_P),and the non-photochemical quenching coefficient(NPQ).In addition,GSH application increased the photochemical quantum yield(Y(Ⅱ))and relative deviation from full balance between the photosystems(β/α–1)and decreased the PSⅡ excitation pressure(1–q_P)and quantum yield of non-regulated energy dissipation(Y(NO))in leaves of salt-stressed tomatoes without BSO(L-buthionine-sulfoximine,an inhibitor of key GSH synthesis enzymeγ-glutamylcysteine synthetase)or with BSO.Further,the addition of GSH depressed the accumulation of H_2O_2 and malondialdehyde(MDA),induced the redistribution of absorbed light energy in PSⅡ reaction centers,and improved the endogenous GSH content,GSH/GSSH ratio and activities of H_2O_2-scavenging enzymes(including superoxidase dismutase(SOD),catalase(CAT),peroxidase(POD)and key enzymes in the AsA-GSH cycle and Grx system)in the chloroplasts of salt-stressed plants with or without BSO.Therefore,GSH application alleviates inhibition of salt-induced growth and photosynthesis mainly by overcoming stomatal limitations,improving the PSⅡ efficiency,and balancing the uneven distribution of light energy to reduce the risk of ROS generation and to mediate chloroplast redox homeostasis and the antioxidant defense system to protect the chloroplasts from oxidative damage.Thus,GSH may be used as a potential tool for alleviating salt stress in tomato plants.