典型耐淹植物主茎死亡特征对水压的响应

陆生植物遭受水淹胁迫,特别是大型水库修建导致的长时间、大深度的水淹,不仅导致光照、溶氧及CO2浓度等环境因子发生显著变化,也导致植物所承受的压力发生明显变化,但是目前关于水压对陆生植物影响的研究鲜见报道.以长江三峡水库消落区典型陆生耐淹植物狗牙根、牛鞭草及瘦瘠野古草为研究对象,进行变量控制实验设计,探究了水压对典型耐淹植物主茎死亡特征的影响.结果表明:1)水压对典型耐淹植株主茎的死亡过程有着显著的促进作用(即表现为正效应);2)不同种类(或耐淹能力不同)的植株在抵抗水压胁迫时,其主茎死亡过程表现出显著差异,并且随着水淹深度的增加继而水压亦增加,这种差异表现得越来越明显.通过本研究,有助于了解陆生植物对水淹环境下水压胁迫的响应机制,并且丰富和发展了关于陆生植物对水淹逆境的响应及适应机制研究的理论和方法.     

充分灌溉下毛白杨树干直径变化对气象因子的响应

以三倍体毛白杨为试验对象,在控制土壤水势不低于-25 kPa的充分灌溉条件下,研究了树干直径变化指标与气象因子的关系。对树干直径日最大收缩量(MDS)产生主要影响的气象因子有参考作物蒸腾蒸散量(ET0)、饱和水气压差(VPD)、日平均温度(T_mean)、日最高温度(T_max)、日最低温度(T_min)、空气相对湿度(RH)、太阳辐射(Rn),其中与ET₀、R_n呈极显著正相关,与T_min、RH、VPD极显著负相关,与T_max呈显著正相关; 树干直径日增长量(DG)主要受R_n的影响,影响树干直径日最大值(MXTD)、树干直径日最小值(MNTD)的气象因子主要是3个温度指标:T_mean、T_max、T_min。MDS可以反映大气干旱程度。温度是影响树干直径增长的重要气象指标     

生姜品种对镉胁迫的生理响应及耐镉性评价

为筛选耐Cd种质资源并研究生姜耐Cd机理,以华东、华中和西南主产区的5个主栽品种凤头姜、贵州小黄姜、罗平小黄姜、竹根姜和山东大姜为试验材料,设置对照(CK)和镉(Cd)处理,两处理的水分处理一致,CK无外源添加Cd。测定生姜生长指标和生理指标,利用主成分分析和隶属函数法对5个品种苗期的耐Cd性进行综合评价。结果表明:Cd处理显著(P<0.05,下同)降低了生姜的株高、茎粗、过氧化氢酶(CAT)活性、光合色素含量及PSⅡ最大光化学效率(F_v/F_m)、光化学猝灭系数(qP);显著升高了叶片中的硫代巴比妥酸反应物(TBARS)含量、超氧化物歧化酶(SOD)活性及非光化学猝灭系数(NPQ);山东大姜的过氧化物酶(POD)活性、游离脯氨酸(Pro)与类胡萝卜素(Car)含量无显著变化。综合评价5个品种生姜的耐Cd性排序为山东大姜>贵州小黄姜>罗平小黄姜>凤头姜>竹根姜。相关性分析结果表明茎粗、Car含量与综合评价值(D值)呈极显著(P<0.01)正相关,叶片TBARS含量、POD活性与D值呈显著负相关(P<0.01)。竹根姜Cd含量是山东大姜的3.57倍,Cd主要富集在根和叶中,山东大姜的Cd主要富集在根中。5个品种中山东大姜耐Cd性最强,竹根姜耐Cd性最差。茎粗、Car含量、叶片TBARS含量和POD活性可以作为生姜耐Cd品种筛选的主要参考指标。     

不同分子量的褐藻寡糖对黄瓜幼苗光合作用及生长的影响

应用不同分子量的褐藻寡糖(ADO)喷施在黄瓜幼苗叶片上,探索不同分子量的褐藻寡糖对黄瓜幼苗的生长情况以及生理特性的影响。结果表明:ADO促进黄瓜幼苗的生长,与对照相比,ADO处理过的幼苗株高、茎粗、株幅和鲜重均有显著增加,且ADO提高了黄瓜叶片中SOD和POD的活力,使得植物体内的氧自由基清除能力提升;ADO还提高叶片中的叶绿素的含量同时使得叶片中净光合速率(P_n)、气孔导度(G_s)、蒸腾速率(T_r)、胞间CO_2浓度(C_i)、叶绿素荧光参数F_v/F_m值均有显著提高。但是,不同分子量的ADO对黄瓜生长的促进效果存在差异,以分子量为8 000的褐藻寡糖处理的效果最好。     

梨枣花果期耗水规律及其与茎直径变化的相关分析

设置4个水分处理,研究了4年生梨枣2010年及2011年花果期不同供水条件下土壤水分动态和耗水规律,分析了梨枣日耗水量与茎直径变化间的相关性,建立回归模型.结果表明:(1)2a内各处理梨枣耗水量随土壤供水量的增加而增大,其日耗水量最大值均出现在灌水后1周内;各处理果实膨大期日耗水强度大于开花坐果期.(2)2a内各处理茎直径日变化平均值(MTD)、茎直径日最大值(MXTD)均符合Logistic函数关系,MXTD与MTD在表征梨枣茎秆生长规律方面效果一致,各处理茎直径变化指标(MTD、MXTD)增长率因水分处理的不同而存在差异.(3)高水分(T1处理)条件下茎直径变化指标(MTD、MXTD、MDS(茎直径日最大收缩量)、DG(茎直径日生长量))在表征枣树耗水状况方面不敏感;在低水分(T4处理)条件下,日耗水量与茎直径日最大收缩量(MDS)相关系数较其他3个茎直径变化指标(MTD、MXTD、DG)高且达极显著水平,说明MDS能够更好的表征低水分处理的梨枣耗水规律.在此基础上建立耗水量与茎直径变化回归模型,为评价梨枣耗水状况提供依据.     

青桐幼苗对水分胁迫的生长及生理响应

青桐观赏效果好,但对其受水分胁迫后的响应机理研究较少,制约了该物种下游产业的发展。为了探究青桐幼苗耐水程度及作用机理,对30%田间持水量（T1）、70%田间持水量（T2）、100%田间持水量（T3）和130%田间持水量（T4）水分胁迫下的青桐幼苗生长指标（株高、茎粗、叶面积）、生物量分配（叶生物量比、茎生物量比、根生物量比）与光合指标（净光合速率、蒸腾速率、胞间CO₂浓度、气孔导度）进行分析。结果表明,随着水分胁迫程度的增加,幼苗的各指标表现为先上升后下降的趋势,当土壤达到T2条件时,幼苗各指标综合表现最佳;T3条件下青桐幼苗净光合速率最高,地上生物量分配较T2条件下高出4%;T2条件下,青桐幼苗叶面积最大,达到196.186 mm²,比叶面积最大,达到512.48,总生物量积累最多,达到17.14 g。当土壤水分达到T2条件时,最适合青桐幼苗生物量积累,可以为幼苗顺利过冬提供充足的储备碳;T4条件下胁迫时间达到10 d,幼苗生长情况出现拐点,胁迫前10 d内幼苗生长较快,但当水分持续性胁迫超过10 d后,幼苗生长趋势减弱,同时萌发出气生根用以响应淹水情况;T1条件下,对青桐幼苗影响极大,最不适合幼苗生长发育。研究结果为青桐幼苗受水分胁迫后的响应机制提供了理论基础。     

加气灌溉对温室番茄生长、产量及品质的影响

本试验目地是探明加气灌溉不同灌水量和加气灌水频率对温室番茄生长、产量和品质的影响,为实际生产应用奠定基础。采用温室小区对照试验,设置3个不同作物-皿系数K_cp（K_cp=0.8、K_cp=1.0、K_cp=1.2）和2个加气灌水频率（1次/3d、1次/6d）共组成6个处理,均以对应的不加气灌溉为对照,比较不同处理对番茄植株生长及果实产量和品质的影响。结果表明,在相同的灌溉频率及灌水量下,加气灌溉可以提高番茄的生长量、产量及品质,加气灌溉的番茄株高较不加气灌溉增加1.44%、茎粗增加3.02%、产量增加19.49%;加气灌溉有利于温室番茄茎粗、株高的生长,并且对番茄的产量和品质均有利。加气灌溉处理时,在相同的灌水量条件下,1次/6d较1次/3d的加气灌水频率,株高增加了8.08%,茎粗增加了6.33%,产量增加了26.01%。由此得出：加气灌溉对植株生长量及果实产量和品质的影响明显优于不加气处理;灌水频率为1次/6d且K_cp=1.0的处理最有利于番茄生长量的积累、产量的提高和品质的改善。     

LED光质对猴樟幼苗生长和光合特性的影响

为研究不同光质对猴樟生长及光合作用的影响，对猴樟幼苗开展了LED光源控制试验。设置红光、蓝光、红蓝（7:3）复合光和白光（对照）4个处理，测定了猴樟的生物量、光合参数和叶绿素荧光参数等指标，并运用主成分分析法对4种光质进行了综合评价。结果表明，处理5个月后，与白光相比，红光除增大了最大光化学效率（F_v/F_m）之外，其在猴樟苗的株高、地径、生物量、净光合速率（P_n）和水分利用效率（WUE）上都显著减小，即红光抑制了猴樟苗的生长和表观光合作用。蓝光下猴樟苗生长性状与白光类似，但P_n和F_v/F_m 减小，Y（NO）增大，说明蓝光显著抑制光合。红蓝光下除了地径减小、叶生物量增大之外，其余指标与白光没有明显差异。4种光质对猴樟苗的综合效应优劣顺序为白光＞红蓝光＞蓝光＞红光。白光下综合表现最优，红光下最差。猴樟设施化育苗中应首选白光和红蓝光等复合光源。     

氮、水处理对刨花楠一年生扦插苗光合特性 和生物量分配的影响

采用棚内盆栽控水与添氮方法,以1a生刨花楠扦插苗为研究对象,通过设置不同的氮、水复合处理试验,研究氮、水对刨花楠幼苗光合特性和生物量分配的影响。结果表明:(1)干旱胁迫会显著降低幼苗的净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(E)、总生物量和叶重比,增加茎重比,但对胞间CO2浓度、根重比和根冠比影响不显著;(2)低氮添加后幼苗的净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(E)均大于对照,而高氮添加反而会抑制幼苗的光合作用;氮添加(低氮和高氮)后幼苗的总生物量均大于对照,但氮添加后对幼苗生物量在不同器官间的分配趋势影响不明显;(3)水分与施氮交互作用对幼苗光合特性和生物量分配均无显著影响。因此,在幼苗生长过程中一定要保证其充足的供水。     

臭氧胁迫对不同敏感型水稻茎秆抗倒性状的影响

为了研究臭氧胁迫对不同敏感类型水稻成熟期茎秆抗倒性状的影响,利用自然光气体熏蒸平台,以23个水稻品种或株系为供试材料,设置室内对照(10 n L·L-1)和臭氧浓度增高(100 n L·L-1)处理,利用组内最小平方和的动态聚类方法,将所有供试材料按地上部成熟期生物量对臭氧胁迫的响应从小到大依次分为A类(-19%)、B类(-39%)和C类(-52%)3个类别。臭氧胁迫环境下A、B和C类水稻倒3节间抗折力降幅差异不显著,均为19%~20%;但倒4节间抗折力分别下降28%、36%和44%,降幅因类型不同而异,与原位测定的植株田间抗折力的变化趋势一致。臭氧胁迫使水稻基部节间的长度、干重、单位长度干重、横截面积、长直径、短直径和茎壁厚均显著或极显著下降,节间干重降幅最大(平均58%),长直径、短直径以及茎壁厚的降幅最小(平均13%~15%);不同节间比较结果显示,臭氧胁迫对这7个参数的影响多表现为第4节间第3节间,其中臭氧处理与节间互作对节间长度、单位长度干重、横截面积、长直径和短直径的影响均达极显著水平;从不同类型看,臭氧胁迫下上述指标的降幅多表现为C类B类A类水稻,其中臭氧处理与水稻类型的互作对节间横截面积、长直径和短直径的影响均达极显著水平。相关分析表明,臭氧胁迫下基部两节间抗折力的响应与对应节间横截面积、长直径、短直径和节间单位长度干重的响应多呈明显的线性正相关。以上结果说明,100n L·L-1臭氧浓度使不同类型水稻茎秆质量明显变劣,臭氧胁迫导致的茎秆抗折力显著下降主要与节间变细相关,其次与节间单位长度干重下降亦有关联。     

Gas exchange and water relations of young potted loquat cv. Algerie under progressive drought conditions

Relationships between plant water status and gas exchange parameters at increasing levels of water stress were determined in Algerie loquats which grown in 50 I pots. Changes in soil water content and stem water potential and their effects on stomatal conductance(G_s) and net photosynthesis(P_n) rate were followed in control plants and in plants without irrigation until the latter reached near permanent wilting point and some leaf abscission took place. Then, the irrigation was restarted and the comparison repeated. Soil water content and stem water potential gradually diminished in response to drought reaching the minimum values of 0.9 mm and –5.0 MPa, respectively, 9 days after watering suspension. Compromised plant water status had drastic effects on G_s values that dropped by 97% in the last day of the drought period. P_n was diminished by 80% at the end of the drought period. The increasing levels of water stress did not cause a steady increase in leaf temperature in non-irrigated plants. Non-irrigated plants wilted and lost some leaves due to the severity of the water stress. However, all non-irrigated plants survived and reached similar P_n than control plants just a week after the irrigation was restarted, confirming drought tolerance of loquat and suggesting that photosynthesis machinery remained intact.     

Features and applications of a field imaging chlorophyll fluorometer to measure stress in agricultural plants

Most non-destructive methods for plant stress detection do not measure the primary stress response but reactions of processes downstream of primary events. For instance, the chlorophyll fluorescence ratio F_v/F_m, which indicates the maximum quantum yield of photosystem II, can be employed to monitor stress originating elsewhere in the plant cell. This article describes the properties of a sensor to quantify herbicide and pathogen stress in agricultural plants for field applications by the F_v/F_m parameter. This dedicated sensor is highly mobile and measures images of pulse amplitude modulated (PAM) chlorophyll fluorescence. Special physical properties of the sensor are reported, and the range of its field applications is defined. In addition, detection of herbicide resistant weeds by employing an F_v/F_m-based classifier is described. The PAM-imaging sensor introduced here can provide in-field estimation of herbicide sensitivity in crops and weeds after herbicide treatment before any damage becomes visible. Limitations of the system and the use of a classifier to differentiate between stressed and non-stressed plants based on sensor data are presented. It is concluded that stress detection by the F_v/F_m parameter is suitable as an expert tool for decision making in crop management.

     

Effects of Root-Zone Temperature on Growth,Chlorophyll Fluorescence Characteristics and Chlorophyll Content of Greenhouse Pepper Plants Grown under Cold Stress in Southern China

In Southern China, plants are usually exposed to cold stress during winter in an unheated greenhouse, but due to the high energy consumption and costs, most of the greenhouses remain unheated. In an attempt to find a simple and affordable solution to this problem, this study was undertaken. In this research, Capsicum frutescens L. plants were studied to investigate the effect of different root zone temperatures on its growth and chlorophyll fluorescence characteristics under cold stress. The plants were cultivated under cold stress conditions in a root zone temperature (RZT) control system where the roots were subjected to four different root-zone temperature treatments of 20°C-T20, 25°C-T25, 45°C-T45 and a control CK group. Growth characteristics studied included plant height, stem diameter, plant width, root length, biomass accumulation. Whilst fluorescence characteristics investigated were chlorophyll fluorescence ratio F_v/F_m, photochemical quenching (qL), efficiency of Photosystem II (Y[II]) and electron transport rate (ETR). Chlorophyll content in the leaves of the plants was also investigated. The findings demonstrated that plants in the CK group suffered a detrimental effect on the growth characteristics registering the lowest values in the measured variables. Conversely, the highest values were observed in T25 RZT treatment. In fluorescence characteristics, values of F_v/F_m were maintained at between 0.8 and 0.83 but also suffered a photo-inhibitory depression in CK and T45 RZT treatments to F_v/F_m values of <0.79. This depicted that root zone heating protected the PS II of these plants from photoinactivation induced by cold stress. Similar trends were seen in the qL, Y[II], ETR values with the T20 and T25 treatments registering the highest values. Chlorophyll content was significantly higher in the leaves of the plants in the T20 and T25 group. The lowest chlorophyll content was recorded in the CK group. Plants in all the treatments accumulated more biomass in the shoot than in the roots as depicted by a significantly lower shoot to root ratio values with the exception of those in the CK group. The findings of this study suggest that pepper plants can successfully be grown in an unheated greenhouse in the Yangtze River Delta area of Southern China during winter by heating the root zone of the plants to a RZT value of 25°C, thereby providing a simple, affordable and cost-effective technique.     

Evaluation of Chlorophyll Content and Fluorescence Parameters as Indicators of Drought Tolerance in Barley

Drought is a major abiotic stress that severely affects food production worldwide. Agronomic and physiological traits associated with drought tolerance are suitable indicators for selection of drought tolerance genotypes to reduce the impact of water deficit on crop yield in breeding program. The objective of this study was to identify indicators related to drought tolerance through analysis of photosynthetic traits in barley （Hordeum vulgare L.）. These traits included chlorophyll content, initial fluorescence （Fo）, maximum primary yield of photochemistry of photosystem Ⅱ （Fv /Fo） and maximum quantum yield of photosystem Ⅱ （Fv/Fm）. Four genotypes （Tadmor, Arta, Morocco9-75 and WI2291） variable in drought tolerance were used to investigate the correlation between these traits and drought tolerance. The results reflected that all of these traits were affected negatively in the four genotypes at different levels of post-anthesis drought stress, but the decrease in drought tolerant genotypes was much less than that of drought sensitive genotypes. The results further revealed that the components of the photosynthetic apparatus could be damaged significantly in drought sensitive genotypes, while drought tolerant genotypes were relatively less affected. On the other hand, the values of chlorophyll content, Fo, Fv/Fo and Fv/Fm in drought tolerance genotypes were significantly higher than those in drought sensitive genotypes under drought stress. It was concluded that chlorophyll content, Fo, Fv/Fo and Fv/Fm could be considered as reliable indicators in screening barley germplasm for drought tolerance.     

斜生四链藻对水中四环素的胁迫响应及去除作用

四环素由于其低生物降解性和水溶性而在水环境中持续存在,对生态环境安全造成较高的潜在风险。为探讨水环境中残留的四环素与藻类的相互作用,以斜生四链藻为研究对象,考察了斜生四链藻对水中不同浓度四环素(0.5、1.0、1.5、2.5、4.0和6.0 mg·L^-1)的胁迫响应及去除作用。结果表明,各浓度四环素处理组均对斜生四链藻的生长产生抑制作用,最高抑制率达到了72.99%,四环素对斜生四链藻的半数效应质量浓度(96 h-EC50)和抑制效应为80%质量浓度(96 h-EC80)分别为2.46和6.9 mg·L^-1。在相同浓度四环素胁迫下,斜生四链藻的光合色素含量和Fv/Fm值呈现出和斜生四链藻细胞密度变化相同的趋势,与对照组相比,6.0 mg·L^-1浓度处理组中斜生四链藻的叶绿素a、叶绿素b和类胡萝卜素含量在96 h的抑制率分别是87.32%、66.91%和87.58%,Fv/Fm值降幅达到了77.4%。在低、中、高浓度四环素(0.5、1.5和6.0 mg·L^-1)胁迫下暴露96 h,斜生四链藻的丙二醛(...     

Stem flow of seed-maize under alternate furrow irrigation and double-row ridge planting in an arid region of Northwest China

Maize is widely planted throughout the world and has the highest yield of all the cereal crops. The arid region of Northwest China has become the largest base for seed-maize production, but water shortage is the bottleneck for its long-term sustainability. Investigating the transpiration of seed-maize plants will offer valuable information for suitable planting and irrigation strategies in this arid area. In this study, stem flow was measured using a heat balance method under alternate furrow irrigation and double-row ridge planting. Meteorological factors, soil water content(θ), soil temperature(Ts) and leaf area(LA) were also monitored during 2012 and 2013. The diurnal stem flow and seasonal dynamics of maize plants in the zones of south side female parent(SFP), north side female parent(NFP) and male parent(MP) were investigated. The order of stem flow rate was: SFPMPNFP. The relationships between stem flow and influential factors during three growth stages at different time scales were analyzed. On an hourly scale, solar radiation(Rs) was the main driving factor of stem flow. The influence of air temperature(Ta) during the maturity stage was significantly higher than in other periods. On a daily scale, Rs was the main driving factor of stem flow during the heading stage. During the filling growth stage, the main driving factor of NFP and MP stem flow was RH and Ts, respectively. However, during the maturity stage, the environmental factors had no significant influence on seed-maize stem flow. For different seed-maize plants, the main influential factors were different in each of the three growing seasons. Therefore, we identified them to accurately model the FP and MP stem flow and applied precision irrigation under alternate partial root-zone furrow irrigation to analyze major factors affecting stem flow in different scales.     

不同水分状况下几种幼树地径日变化研究

[目的]研究几种幼树在不同土壤水分条件下的地径变化规律。[方法]以油松、侧柏、元宝枫和刺槐为试材,测定了土壤含水率为18.75%1、6.47%、13.13%、9.78%和7.50%时的地径日变化规律。[结果]不同水分处理对幼树的地径日变化有显著影响。在土壤含水率为18.75%时,刺槐的日最大收缩量(MDS)最小,为0.144 mm;土壤含水率为7.50%时,其MDS值则增大至0.356 mm。在土壤含水率为16.47%时,元宝枫的MDS值最小,而土壤含水率7.50%时的MDS值最大。在土壤含水率为7.50%时,油松和侧柏地径的MDS值最大,其他各处理水平的MDS值很接近。油松、元宝枫和刺槐晴天的每日最大收缩量比阴天大。[结论]不同试材地径的最大值均出现在上午8:00,每日的茎直径最小值出现在午后。     

新疆滴灌冬小麦灌溉量对产量形成与水分利用的影响

为优化新疆北疆滴灌冬麦区节水灌溉技术,探讨滴灌量对冬小麦产量形成及水分利用的影响,2013—2015年设置0(CK)、900(W1)、1 800(W2)、2 700(W3)、3 600(W4)、4 500(W5)、5 400(W6)、6 300m3/hm2(W7)共8个灌溉量处理,测定不同滴灌量下冬小麦叶面积指数、SPAD值、光合特性、干物质积累、产量及耗水特性的变化。结果表明:各处理冬小麦随生育进程递进LAI均呈现单峰型变化趋势,在孕穗期达到最大,其值以W5最高;叶片最高SPAD值出现时期随滴灌量增加而后延。叶片净光合速率、蒸腾速率、气孔导度及单茎干物质最大增长速率(Vm)均以W5处理最高。随着滴灌量的增加,冬小麦籽粒产量及水分利用效率(WUE)均呈"先升后降"的变化趋势,W5处理获得最高产量,而W4处理获得最大水分利用效率。因此,在本试验条件下,滴灌量为3 600~4 500m3/hm2的处理为高产高效的最适灌溉水平。     

Evaluation of photosynthesis,physiological, and biochemical responses of chickpea (Cicer arietinum L. cv. Pirouz) under water deficit stress and use of vermicompost fertilizer

One goal in the face of drought stress conditions is to increase growth and yield through the reduction of negative effects of stress. Vermicompost can play an effective role in plant growth and development and in reducing harmful effects of various environmental stresses on plants due to its porous structure, high water storage capacity, having hormone-like substances, plant growth regulators, and high levels of macro and micro nutrients. This study considered the physiological, biochemical, and photosynthetic responses of the chickpea to different combinations of vermicompost and water stress in a greenhouse environment. Two factors were involved, addition of vermicompost to soil at four ratios: control (100 wt% (weight percentage) soil); 10 wt% vermicompost+90% soil; 20 wt% vermicompost+80 wt% soil; 30 wt% vermicompost+70 wt% soil weight percentage, and treatment of water stress at three levels including 75, 50, and 25% of field capacity. The results showed that vermicompost had a significant effect on all traits under stress and non-stress conditions. Application of vermicompost in soil, especially at the levels of 20 and 30 wt% significantly increased all studied traits under non-stress conditions. Under moderate stress conditions, vermicompost at 30 wt% treatment resulted in a significant increase in the photosynthetic pigments, CO₂ assimilation rate, internal leaf CO₂ concentration, transpiration, the maximal quantum yield of photosystem II (PSII) photochemistry (F_v/F_m), concentrations of Ca and K in root and leaf tissues, proline and soluble protein contents in root tissues. Peroxidase (POX) and catalase (CAT) enzyme activities decreased significantly with increasing proportions of vermicompost, but the activity of superoxide dismutase was not significantly different. In conclusion, the above results showed that vermicompost fertilizer had a positive effect on physiological, biochemical, and photosynthetic responses of chickpea under non-stress and moderate stress conditions, but no positive effect was determined under severe water stress.     

宁夏引黄灌区大豆农艺及产量性状分析

对宁夏黄灌区大豆农艺及产量性状的相关分析表明,株高与茎粗、底荚高度和主茎节数,生育时间与株高、主茎节数和百粒质量呈显著正相关;单株有效荚数与单株粒数、单株粒质量,单株粒数与单株粒质量、单位面积产量呈极显著正相关;单株粒数、单株荚数与百粒质量呈显著负相关。主成分分析确定4个主成分因子为产量、粒质量、茎粗和百粒质量。在所设计密度范围内有效荚数、单株粒数、粒质量和经济系数随密度的增大而减少。模拟产量回归方程表示为y=-1.962 6x2+6.639 2x+5.339 3(r2=0.846 5),解得密度在1.69×104/666.7m2时,可获得最高产量405.73kg/666.7m2。