野生大豆、半野生大豆和栽培大豆对苗期干旱胁迫的生理反应

以野生、半野生和栽培大豆为材料,在旱棚盆栽条件下进行苗期干旱胁迫试验.对叶绿素含量、光合速率、脯氨酸含量、丙二醛(MDA)含量、相对电导率、可溶性糖(WSS)含量、超氧化物歧化酶(SOD)活性、过氧化物酶(POD)活性、过氧化氢酶( CAT)活性进行测定.结果表明,在干旱胁迫下,叶绿素含量、光合速率、可溶性糖含量、脯氨酸含量及SOD活性表现为野生大豆＞半野生大豆＞栽培大豆;而丙二醛含量、相对电导率、POD活性则表现为野生大豆＜半野生大豆＜栽培大豆.干旱胁迫下不同类型材料各生理指标与正常供水条件相比都发生不同程度的变化,叶绿素含量、光合速率降幅为野生大豆＜半野生大豆＜栽培大豆;脯氨酸含量增幅为野生大豆＞半野生大豆＞栽培大豆;而丙二醛(MDA)含量、相对电导率、SOD活性、POD活性,CAT活性增幅变化顺序为野生大豆＜半野生大豆＜栽培大豆.在干旱胁迫下,野生大豆、半野生大豆和栽培大豆的生理指标发生显著变化,3种类型大豆的变化幅度差异显著.野生大豆在干旱胁迫下生理指标的表现优于半野生大豆和栽培大豆.     

干旱胁迫对持绿性甘蔗细茎野生种叶片生理和生物量的影响

以高持绿性甘蔗细茎野生种(云瑞08-254)和低持绿性甘蔗细茎野生种(云瑞09-525)为试验材料,在干旱胁迫和正常浇水两个条件下,研究干旱胁迫对甘蔗叶片生理活性和生物量的影响。结果表明:干旱胁迫下,云瑞08-254的叶片SOD、CAT和MDA含量都明显增加,而云瑞09-525叶片SOD、CAT、POD和MDA含量均明显降低;云瑞08-254的相对电导率增幅显著小于云瑞09-525,云瑞08-254的质膜受损程度相对较小;与云瑞09-525相比,云瑞08-254在干旱胁迫后脯氨酸、可溶性糖和可溶性蛋白含量升高幅度较为明显,且本身即具有较高的脯氨酸、可溶性糖和可溶性蛋白含量。在干旱胁迫条件下,持绿性甘蔗细茎野生种能通过产生保护性物质降低对干旱的敏感性,通过调节SOD、CAT和POD活性以及MDA、脯氨酸、可溶性糖和可溶性蛋白含量以及持绿生物量的变化,从而减轻干旱的伤害,表现出更好的抗旱性。     

马铃薯对旱胁迫的反应

为探讨干旱胁迫对马铃薯生理机制的影响,以抗旱性不同的马铃薯品种台湾红皮、会-2和早大白为试材,研究干旱胁迫下马铃薯相关生理指标的变化。结果表明:随着胁迫时间的延长,质膜相对透性、丙二醛(MDA)含量、脯氨酸(Pro)含量增加,而抗坏血酸(AsA)含量降低,超氧化物岐化酶(SOD)和过氧化物酶(POD)活性先升高后降低。抗旱性强的品种质膜相对透性、MDA含量增加的幅度较小,Pro含量增加幅度较大,AsA含量降低的幅度较小,SOD和POD的活性也较高,而抗旱性弱的品种则相反,这些指标及其变化可以作为鉴定马铃薯抗旱能力的依据。     

干旱胁迫对中粒种咖啡幼苗膜脂过氧化、抗氧化酶活性和渗透调节物质含量的影响

以苗龄约8个月的中粒种咖啡袋育苗为材料,测定3种干旱胁迫强度下咖啡幼苗叶片的生理指标变化,旨在了解其对干旱胁迫的生理响应。结果表明:在轻度干旱胁迫下(土壤相对含水量为55%~60%),与对照相比,中粒种咖啡幼苗叶片的可溶性蛋白、可溶性糖、脯氨酸含量、超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)活性极显著增加,而丙二醛(MDA)含量和相对电导率没有显著变化。但在中度干旱或重度干旱胁迫下(土壤相对含水量为40%~45%或25%~30%),可溶性蛋白含量、SOD、POD、CAT活性显著或极显著减少,而可溶性糖、脯氨酸的积累减缓,MDA含量和相对电导率迅速上升。在适度干旱胁迫下,中粒种咖啡幼苗可通过提高抗氧化酶活性和渗透调节能力来增强其对干旱胁迫的耐性。     

短期干旱胁迫和复水对巴西蕉幼苗生理特性的影响

研究了我国香蕉主栽品种巴西蕉幼苗在短期干旱胁迫和复水情况下叶和根有关生理指标的变化。结果表明:干旱胁迫下,巴西蕉幼苗叶片质膜透性和MDA含量与对照相比显著提高,脯氨酸和可溶性蛋白含量显著增加,SOD和POD活性显著提高,根系活力显著下降。复水后,3个胁迫程度下巴西蕉幼苗叶片质膜透性和MDA含量得到不同程度的恢复,与干旱胁迫相比显著下降;脯氨酸和可溶性蛋白含量、SOD和POD活性与对照相比显著提高;根系活力3个胁迫程度得到不同程度的恢复,其中轻度胁迫恢复最好,且比常温对照显著升高。表明抗旱锻炼提高了巴西蕉幼苗的抗旱性。     

氮素对模拟胁迫下土沉香幼苗抗旱生理的影响

以土沉香3个种源的幼苗为材料,用PEG6000模拟水分胁迫,研究氮素营养与水分胁迫对土沉香不同种源幼苗相关生理生化指标的耦合影响.结果表明:不同处理的相对电导率、超氧化物歧化酶(SOD)活性、过氧化氢酶(CAT)活性、游离脯氨酸(Pro)质量分数和丙二醛(MDA)质量摩尔浓度差异显著.正常水分条件下,高氮处理(氮素浓度为15 rtmol/L)有利于提高抗氧化酶(SOD,POD,CAT)活性和Pro质量分数,但造成一定程度的渗透胁迫,使MDA质量摩尔浓度和相对电导率升高.水分胁迫条件下,高氮处理的相对电导率、MDA质量摩尔浓度均小于低氮处理(氮素浓度为7.5 mmol/L),而CAT活性、Pro质量分数大于低氮处理,POD活性对氮素营养及水分处理不敏感.3个种源之间相对电导率差异显著,高低顺序为琼中种源＞临高种源＞澄迈种源.尽管3个种源的SOD和CAT活性以及Pro质量分数和MDA质量摩尔浓度略有不同,但在-0.63 MPa水分胁迫条件下,高氮处理有利于提高3个种源的抗旱性.     

稀土元素钕对玉米幼苗根系抗旱性的影响

采用10%聚乙二醇6000模拟干旱胁迫,研究稀土元素钕对干旱胁迫下玉米幼苗根系抗旱性的影响。结果表明,干旱胁迫显著提高根系丙二醛(MDA)含量和过氧化氢(H_2O_2)含量,提高超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性,显著降低了过氧化物酶(POD)、谷胱苷肽转移酶(GST)、谷胱甘肽过氧化物酶(GPX)活性,显著降低抗坏血酸(As A)和谷胱苷肽(GSH)含量及根系生物量。干旱胁迫加剧了根系的氧化胁迫,玉米幼苗根系通过增强抗氧化酶活性抵抗干旱胁迫。外源氯化钕(NdCl_3)处理可显著提高干旱胁迫下玉米幼苗根系抗氧化酶SOD、POD、CAT、GST、GPX活性,显著提高AsA和GSH含量和根系生物量,显著降低MDA和H_2O_2含量,对APX活性无显著影响。盆栽实验结果进一步说明,NdCl_3对轻度和中度土壤干旱下玉米幼苗抗旱性均具有促进作用,对中度土壤干旱下玉米幼苗的抗旱性促进作用更佳。NdCl_3可提高玉米幼苗根系的抗旱能力,缓解干旱胁迫造成的伤害。     

硅对干旱胁迫下野生大豆幼苗生长和生理特性的影响

为探讨外源硅对干旱胁迫下野生大豆生长的影响,以野生大豆为试验材料,研究不同浓度外源硅对干旱胁迫下大豆幼苗的生长及生理特性的影响。结果表明:干旱胁迫会使野生大豆鲜重、干重、叶绿素含量、根系活力及SOD、CAT、POD活性降低,细胞膜透性、MDA、游离脯氨酸及可溶性糖含量增加。随着硅处理浓度的不断升高,野生大豆鲜重、干重、叶绿素含量、根系活力逐渐增加;低浓度硅胁迫提高了SOD、CAT、POD活性,降低了细胞膜透性、MDA、游离脯氨酸及可溶性糖含量,随着硅胁迫浓度的不断提高,SOD、CAT、POD活性逐渐下降,细胞膜透性、MDA、游离脯氨酸及可溶性糖含量先下降再升高。说明一定浓度的外源硅能有效促进干旱胁迫下野生大豆幼苗的生长,提高抗氧化酶活性,降低细胞膜透性、MDA、游离脯氨酸及可溶性糖含量,能够缓解干旱胁迫对野生大豆幼苗的危害,提高野生大豆抗旱能力。     

外源腐胺对干旱胁迫下冬小麦幼苗叶片膜脂过氧化的调节效应

为了研究外源物质对小麦抗旱性的诱导作用,水培条件下研究了外源腐胺对干旱胁迫(15%PEG-6000)条件下冬小麦幼苗叶片膜脂过氧化及抗氧化酶活性的影响.结果表明,干旱胁迫48 h后冬小麦幼苗叶片含水量下降了27.43%, O_2(÷)的产生速率、丙二醛(MDA)和H_2O_2含量随时间的推移均呈增加的趋势,SOD、POD、CAT活性分别下降了23%、37%、70%.外源腐胺处理下叶片含水量仅下降了7.62%;叶片 MDA含量降低80%左右,H_2O_2的含量下降50%左右,O_2(÷)的产生速率降低了1/3,而叶片SOD、POD、CAT活性分别提高了41%、165.8%、246%.因此认为,外源腐胺可通过抑制活性氧(O_2,H_2O_2)的产生,降低MDA含量,提高抗氧化酶(SOD、POD、CAT)的活性,缓解干旱胁迫造成的冬小麦幼苗叶片细胞膜脂过氧化损伤,提高冬小麦的抗旱性.     

不同水平腐胺对巴西蕉幼苗抗旱生理的影响

用0.00、1.00、1.25、1.50、1.75 mmol/L腐胺(Put)喷施巴西蕉幼苗叶片,研究干旱胁迫后其相关生理生化指标的变化。结果表明,在干旱胁迫下,适宜浓度的外源Put预处理能显著增加巴西蕉幼苗叶片的相对含水量,降低相对电导率,提高脯氨酸、可溶性蛋白质的含量及SOD、POD的活性,降低O.-2产生的速率,减少MDA的积累。由此说明适宜浓度的外源Put预处理能提高巴西蕉幼苗抗旱性,以1.25 mmol/L Put预处理效应最佳。     

我国麻类标准现状与分析

介绍了我国麻类标准的现状。通过分析,指出了存在的问题,主要表现在标准体系不完善、标准更新不及时,协调性差及贯彻执行不力等。提出了我国麻类标准应采取的对策。     

Effects of Organic and Chemical Fertilizers and Arbuscular Mycorrhizal Inoculation on Growth and Quality of Cucumber and Lettuce

Summary

Arbuscular mycorrhizae were inoculated into phosphorus-deficient soil fertilized with either organic or chemical fertilizer with cucumber (Cucumis sativus L.) as the first crop and lettuce (Lactu-ca sativa L.) as the second crop but without additional fertilization and AM inoculation. AM increased dry matter and fruit yield of cucumber significantly in the unfertilized, organic-fertilized and P-deficient plants compared with the fully chemical-fertilized plants. AM inoculation increased the available phosphorus in plant and soil by around 30% for all treatments except for those chemically-fertilized. The rate of AM infection did not differ significantly among the fertilization treatments, but the infection intensity was higher in unfertilized, organic-fertilized and phosphorus-deficient treatments than chemical-fertilized treatment. The residual effects of AM-inoculated to cucumber were evident for lettuce in all pre-treatments that were unfertilized and un-inoculated for the second cropping. Without P-fertilization, neither crop could grow optimally even when the soil was inoculated with AM, suggesting that AM could not serve as a substitute for phosphorus fertilizer. However, the other beneficial effects of AM on crop growth and yield could not be fulfilled with phosphorus fertilizer.     

水稻病虫害绿色防控与统防统治融合技术模式示范

2017—2018年,在同安镇粮食产能区示范推广水稻病虫害绿色防控与统防统治融合技术模式,取得了显著成效。融合技术示范区比常规区减少用药2~3次,用药量减少37.6%,防治成本降低400元/hm^2;水稻产量增加12.8%,收益增加2 835元/hm^2。     

Preparation and characterization of fibers of waste and fresh polyethylene terephtalate and mixtures of them

Textile fibers were obtained from secondary polyethylene terephtalate (PET) and its mixtures with primary PET at initial orientation of 18000–33000 %, rate of additional orientation drawing 3.5–6.5 times and temperature of thermal fixation 363–413 K. The fibers’ tensile strength was found to decrease and elongation at break to increase with the decrease of their linear density under the conditions of fibers formation. For the fibers based on polymer mixtures, the presence of oxidized fragments in the secondary PET limited the compatibility of the two polymers which resulted in deteriorated tensile properties. The linear density (4–16 dtex), tensile strength (30–50 cN/tex) and elongation at break (20–60 %) of the PET fibers obtained were close to these for the industrially produced polymer fibers. The values of the average diameter of the fibers formed and oriented under laboratory conditions allows classifying them between the fine and the coarse textile fibers which makes them suitable for the textile industry.     

春季氮肥和多效唑调控对小麦生育和产量的影响

为明确春季调控措施对冬小麦生长发育和籽粒产量的影响,以冬小麦品种石新828为材料进行田间试验,4个处理分别为:起身期追全部氮肥(除基肥外,下同)并叶面喷多效唑(N1);起身期追2/3氮肥并喷多效唑+拔节期追1/3氮肥(N2);起身期追1/3氮肥+拔节期追2/3氮肥(N3);拔节期追全部氮肥(N4)。生育期间测定群体和个体生育特性,成熟期调查产量性状。结果表明,N1和N2处理小麦拔节期的总茎数、叶面积指数(LAI)和干物质积累量均显著高于N4和N3处理。孕穗期N4和N3处理小麦的总茎数、LAI和干物质积累量显著高于N1和N2处理。开花到成熟期各处理的总茎数、LAI和干物质积累量差异均不显著。孕穗期前,不同处理的株高差异不显著,孕穗期后,N4处理的株高最高,且显著高于N1处理。各处理基部节间直径和中上部节间长的差异不显著,N4处理基部第一节间长度显著大于其他处理。随追氮时期前移或前期施氮量增多,不孕小穗数减少,结实小穗和穗粒数增加,N1比N4处理不孕小穗数显著减少,结实小穗和穗粒数显著增多。N1处理小麦成熟期的千粒重最高,且显著高于N4处理。N1处理的籽粒产量最高,且显著高于N3和N4处理。起身期追氮配合多效唑调控,可以获得比拔节期追氮更高的穗粒数和千粒重,从而获得更高的产量。     

Interactive Effects of Sodium and Potassium on the Growth and Photosynthesis of Spinach and Komatsuna

Abstract

Two cultivars of spinach and one cultivar of komatsuna were sand cultured using a nutrient solution with Na and K in various combinations. The growth (fresh weight of shoot) of spinach cv. Atlas was significantly increased when 1.4 mM KC1 of the 7 m M KO was replaced with 1.4 mM NaCl, although the growth was reduced when more KC1 was replaced with NaCl. In another spinach cv. All Right, however, NaCl substituting for 20% of KC1 showed no significant effects. In komatsuna, Na used in place of K at any ratio reduced the growth. The growth of spinach cv. Atlas was increased by applying 20 mM NaCl, irrespective of K dose (480 - 2400 mg K₂O per 1/2000 a Wagner pot). The growth of spinach cv. All Right was also increased by 20 mM NaCl when K was at a deficient level (480 - 960 mg K20 per pot), but was not when K was at: an excessive level (1920 - 2400 mg K₂O per pot). In komatsuna, 20 mM NaCl reduced the growth. In spinach, Na prevented the decrease of the photosynthetic rate and stomatal conductance caused by K deficiency.     

白砂糖干燥与冷却机理及影响

砂糖的含水量、装包温度和仓储条件对其贮存保质具有重要影响。本文从白砂糖的含水分特性、干燥机理和生产过程环节等对白砂糖干燥与冷却的影响进行深入分析。由于结晶过程的包裹现象,砂糖含水分可分为表面和内部水分,白砂糖干燥过程只能去除前者。生产过程中煮糖、分蜜操作对内部水分含量有影响。贮存过程的内部水分的扩散是砂糖降质的根本原因,而装包温度和贮存条件是影响内部水分扩散的外在条件。     

海南百香果病虫害种类调查鉴定及其发生危害

百香果是海南省的新兴产业,也是我国多个省区扶贫攻坚的重要产业。病虫害是影响百香果产业的重要因素,随着海南百香果种植面积越来越大,病虫害对百香果产业的不利影响越来越凸显。由于缺乏百香果病虫害种类调查鉴定的基础性研究,许多种植户对田间发生的病虫害种类识别不足,从而影响了百香果病虫害的防控效果。为了摸清海南百香果种植区的病虫害种类,于2019—2021年对海南省儋州市、乐东县、屯昌县、文昌市、三亚市、东方市、保亭县、白沙县、海口市等百香果种植区的病虫害进行了系统调查与鉴定,并对其发生危害特点进行了研究。鉴定发现海南百香果种植区的病害有11种,分别是病毒病、茎基腐病、炭疽病、疮痂病、疫病、灰霉病、果腐病、褐斑病、烟煤病、藻斑病和缺镁。重要病害为病毒病和茎基腐病,危害程度分别为4级和3级,炭疽病和疮痂病危害也较重,危害程度均为2级,其他病害危害较轻。害虫有28种,分别是黄胸蓟马、茶黄蓟马、红带蓟马、美洲棘蓟马、普通大蓟马、咖啡木蠹蛾、美洲斑潜蝇、橘小实蝇、斜纹夜蛾、双线盗毒蛾、绿丽刺蛾、白带锯蛱蝶、烟粉虱、温室白粉虱、柑橘粉蚧、木槿曼粉蚧、藤壶蜡蚧、茶角盲蝽、樟颈曼盲蝽、稻绿蝽、中稻缘蝽、茶小绿叶蝉、丽球瓢蜡蝉、绿鳞象甲、眼斑芫菁、白条豆芫菁、甘薯梳龟甲和朱砂叶螨。重要害虫为黄胸蓟马和咖啡木蠹蛾,危害程度均为3级,茶黄蓟马和美洲斑潜蝇的危害也较重,危害程度均为2级,其他害虫危害较轻。软体动物3种,分别是灰巴蜗牛、同型巴蜗牛和一种尚未鉴定的蛞蝓。本研究明确了海南百香果种植区病虫害具体种类,新发现百香果病害1种和害虫24种,为海南百香果病虫害的精准防控提供技术支撑。     

源库限制对寒地玉米产量及品质的影响

本试验采用4个品种(四单19、本玉9号、DH808、DH3149),2种密度(52500株/hm2、75000株/hm2),并在吐丝期分别进行减源限库处理,研究源库限制对玉米生长发育和产量品质的影响。结果表明:减源处理降低了单株叶面积,也降低了单株干物重。限库处理因库容减少,使得干物质略有增加,但不同品种对源库处理反应不一致。限库处理导致玉米子粒蛋白质含量明显增加,减源处理基本不变或略有增加;减源限库处理导致平展型玉米子粒的脂肪含量增加,而紧凑型品种保持不变或略有降低;减源处理导致淀粉含量的增加,而限库处理的影响相反,导致淀粉含量减少。     

Characteristics of photosynthesis and conductance of potato canopies and the effects of cultivars and transient drought

Gas-exchange characteristics of potato (Solanum tuberosum L.) canopies were determined with crop enclosures under condition of optimal water supply, during soil water depletion, and during recovery from drought-stress. The plants were grown under a rainshelter in large containers with 2-m² surface area. Control plants received water throughout the growth period. In Expt. 1, transient drought was imposed by interrupting water supply completely for 22 days. During the 33-day period of drought treatment in Expt. 2, the stressed plants received half the amount of water that was given to the control plants (irrigations 2–3 times per week).

During soil water depletion, stomatal conductance of the canopy was reduced earlier and more than photosynthesis. This resulted in a lower internal carbon dioxide concentration in the leaves of stressed plants and a higher ratio between photosynthesis and stomatal conductance. The value of that ratio increased as soil water potential dropped.

Water-use efficiency ( ) increased during drought stress. The cultivar Bintje showed a larger ratio between photosynthesis and stomatal conductance of the canopy and a higher than cv. Saturna, both for optimal water supply and during drought stress.

Photosynthesis and conductance of the canopy started to recover immediately upon rewatering, even when relative values had declined to 20–30% during the preceding stress period. After release from stress, the leaves in the top layer of the canopy had a higher stomatal conductance in treated plants than in control plants.