不同光照度对番荔枝幼苗叶片生长发育和光合性能的影响

把“非洲骄傲”(Annona atemoya Hort．et West．cv．Afiican pride)番荔枝实生幼苗分别置于100％、42．2％、21．1％的自然光照度下处理2个月，研究不同光照度对其叶片生长发育及光合性能的影响。结果表明：遮荫条件下叶片宽度生长模式呈双峰型，叶片生长时间延长。遮荫极显著降低了叶片海绵组织、栅栏组织厚度，提高了叶片叶绿素b、总叶绿素和类胡萝卜素含量，降低了叶绿素a与叶绿素b的质量比。在各处理的光照条件下测定的光合指标结果表明：遮荫显著降低了叶片蒸腾速率，遮2层荫网的气孔导度显著低于其它2个处理，光合速率各处理间无显著差异；炼苗1d后在自然光照下测定的番荔枝幼苗单叶光合速率、蒸腾速率、气孔导度都随着叶片发育过程中所处光照度的增加而增强。     

美洲斑潜蝇为害对棉花光合生理的影响

美洲斑潜蝇幼虫潜食棉花栅栏组织后,叶片中叶绿素a、b以及叶绿素总量都较对照减少,并且随着受害级别的增高,减少量逐渐增大;当虫害达到5级时,棉花叶片的叶绿素总量仅相当于对照的68.3％.随着叶片受害级别的增高,棉花叶片的光合速率呈下降趋势;当虫害达到5级时,叶片的光合速率仅相当于对照的23.1％.同时,棉花叶片的气孔导度和蒸腾速率也随其受害级别的增高而降低;当虫害达到5级时,叶片的气孔导度和蒸腾速率仅相当于对照的20.7％和33.3％.     

大气CO2浓度升高对茶树光合生理特性的影响

通过对不同大气CO2浓度水平下的茶树观测试验,研究了大气CO2增长对茶树新梢叶片净光合速率、蒸腾气孔导度、水分利用效率、叶绿素含量和营养元素含量等光合生理特性的影响。结果表明,在大气CO2浓度为550、750μmol·mol-1时,比正常大气CO2水平下茶树叶片日平均净光合速率提高17.9%和25.8%,并缓解和消除了光合午休现象;茶树叶片气孔导度降低7.6%和13.0%,蒸腾速度稍有下降,水分利用效率提高21.6%和35.8%;同时使茶树新梢叶绿素a、叶绿素b、叶绿素总量和类胡萝卜素含量分别提高12.8%～18.4%、14.0%～22.0%、13.1%～19.4%和17.2%～20.1%,但叶绿素a与叶绿素b的比值有所降低。大气CO2浓度的升高使新梢营养元素N、K、Ca含量有不同程度降低,而Mg、Fe、Zn、Mn、Cu含量有所增加。     

Effect of La(NO3)3 on the Physiological Indices of Cold Tolerance in Livistona chinensis Seedlings

用0、100、200、300、400、500、600 mg/L硝酸镧溶液喷施蒲葵幼苗叶片作为处理,每天喷施1次,连续3d.在20、5、12和10℃下分别处理24h后测定叶片的丙二醛、可溶性糖和叶绿素含量以及叶绿素a/b的比值.结果表明:硝酸镧溶液处理的幼苗丙二醛含量都比对照低,而且随温度变化幅度小,而可溶性糖和叶绿素含量及叶绿素a/b比值均比对照高.硝酸镧处理可有效改善上述蒲葵幼苗的耐寒性生理指标,其中300 mg/L硝酸镧溶液对提高蒲葵幼苗的耐寒性生理指标具有显著的效应.     

硫素水平对夏玉米产量及生理特性影响的研究

每公顷基施0(CK)、36.3(S1)、413.85(S2)kg硫时,玉米每公顷产量分别为9 784.5、10639.5和11322kg,处理分别比对照增产8.73%和15.71%,并提高了果穗长度,增加了穗行数和行粒数,对千粒重影响不大.玉米单株的千物质积累量、株高、绿叶面积、比叶重及光合势、净同化率均表现为S2>S1＞CK.施用硫肥后,提高了功能叶片的叶绿素a、b以及叶绿素总含量,但施硫处理间在前期差异不大,后期S2处理叶绿素含量较高,叶绿素a/b比值各处理间相对稳定.施用硫肥提高了玉米叶片的光合速率,表现为S2>S1＞CK.施用硫肥还提高了玉米植株的气孔导度和蒸腾速率.     

CO2浓度升高对玉米叶片光合生理特性的影响

以沈糯3号为研究材料,利用开顶式气室(OTCs)法研究了二氧化碳(CO2)浓度升高处理下,玉米叶片叶绿素含量、光合生理特性及其子粒产量的变化,揭示CO2浓度升高对玉米光合生理特性及子粒产量的影响机理.结果表明,在整个生育期内,与对照相比,高浓度CO2处理下,玉米叶片叶绿素a、叶绿素b及叶绿素(a+b)的含量增加,而叶绿素a/b的值则先升高后降低;在整个处理期间,净光合速率均高于对照(p＞0.05),升高幅度为12.6%～71.1%,气孔导度低于对照(p＞0.05),其降低幅度为2.9%～18.8%.处理至抽雄期和灌浆期,胞间CO2浓度分别增加152%和161%,均极显著高于对照(p＜0.01);蒸腾速率的变化较小.高浓度CO2处理下,玉米穗粒数和穗粒重均明显高于对照(p＜0.05).CO2浓度升高在一定程度上促进了玉米的光合作用,从而使玉米子粒产量增加.     

旺长期水分胁迫对红麻叶片中叶绿素和胡萝卜素含量的影响

以红麻"杂红992"为试验材料,通过盆栽控水法设置正常灌水(CK)、轻度胁迫(LS)、中度胁迫(MS)和重度胁迫(SS)4个处理,研究不同水分胁迫条件对红麻叶片中叶绿素含量的影响。结果表明:在正常灌水和轻度胁迫下,红麻叶片中的叶绿素a、叶绿素b、叶绿素(a+b)和类胡萝卜素含量随胁迫时间的延长而降低;在中度胁迫和重度胁迫下,红麻叶片中的叶绿素a、叶绿素b、叶绿素(a+b)和类胡萝卜素含量随胁迫时间的延长呈先降低后升高趋势。20 d的水分胁迫后,叶绿素含量SSMSLSCK。随着胁迫程度的增加和胁迫时间的延长,叶绿素a/b值均较对照有所下降,胁迫20 d后趋势变为CKLSMSSS,水分胁迫对红麻叶绿素a的影响大于叶绿素b。红麻在较低的土壤水分含量情况下,可以保持较高的叶绿素含量,这在一定程度上也证明了红麻是耐旱性强的作物。     

不同大豆品种幼苗叶片光合及叶绿素荧光 特性对套作遮荫的响应

选用4个耐荫性有差异的大豆品种为材料,通过与单作比较,研究了不同大豆品种幼苗叶片光合及叶绿素荧光特性对套作遮荫的响应差异。结果表明,套作遮荫提高了大豆叶片叶绿素含量、总叶绿素与类胡萝卜素比值（Chl(a+b)/Car）、胞间二氧化碳浓度（Ci）、水分利用效率（WUE）、叶片初始荧光（Fo）、PSⅡ有效光化学量子产量（Fv′/Fm′）和实际光化学效率（ΦPSⅡ）;使叶绿素a与叶绿素b比值（Chla/b）、类胡萝卜素(Car)含量、净光合速率（Pn）、气孔导度（Gs）、气孔限制值（Ls）、蒸腾速率（Tr）、PSⅡ最大光化学量子产量（Fv/Fm）、光化学荧光猝灭系数（qP）、非光化学荧光猝灭（NPQ）呈减小趋势。套作遮荫降低了大豆地上部分干物质积累量,其干物质积累量与Pn呈极显著正相关。耐荫性相对较好的材料,如贡选1号和南豆12在套作遮荫下Pn下降较少,且有着相对较高的Chlb、Car分子组成比例、Fo和Fv/Fm。     

氮素形态对油麦菜幼苗光合作用及其荧光特性的影响

采用水培技术,以两叶一心的油麦菜幼苗为材料,研究铵态氮和硝态氮不同配比对油麦菜幼苗叶片光合色素含量、光合作用和叶绿素荧光参数的影响。结果表明:(1)不同氮素处理对油麦菜幼苗叶片中叶绿素a、叶绿素b和类胡萝素的含量均产生显著影响,当NO_3~-∶NH_4~+=7∶3时叶绿素a、叶绿素b和类胡萝素的含量明显增加,显著高于其他处理。(2)各处理下油麦菜幼苗的净光合速率、气孔导度、蒸腾速率随处理时间的增长呈上升趋势,而胞间CO_2浓度则呈下降趋势,当NO_3~-∶NH_4~+=7∶3时净光合速率、气孔导度和蒸腾速率显著高于其他处理,而胞间CO_2浓度则显著低于其他处理。(3)油麦菜幼苗叶片荧光特性呈现出较大差异,当硝态氮与铵态氮的配比为7∶3时,油麦菜幼苗叶片PSⅡ的Fv/Fm和Fv/F0最高;由相关性分析可知,Fv/Fm、Fv/F0与叶绿素a和类胡萝卜素的相关性高于叶绿素b;Fv/Fm和Fv/F0三元回归模型的决定系数均在0.9以上,准确反映出油麦菜幼苗叶片叶绿素荧光动力学参数与光合色素之间的关系。     

干旱胁迫对苎麻叶绿素含量的影响

以苎麻品种川苎11号为材料,采用盆栽控水试验,设置轻度干旱、中度干旱、重度干旱和正常灌水处理(对照),研究了干旱胁迫持续10天、15天、20天对苎麻旺长期植株光合色素的影响.结果表明,干旱胁迫下苎麻叶片叶绿素a、叶绿素b、叶绿素总含量明显降低;与对照相比,叶绿素a含量低7.59%-31.53%,叶绿素b含量低10.15%-36.30%,叶绿素总含量低8.41%-29.78%;干旱胁迫对苎麻叶绿素b的影响大于叶绿素a.短时间严重干旱胁迫使苎麻叶绿素a/b值显著上升,轻度胁迫和长时间严重干旱胁迫对叶绿素a/b值影响很小.总之,干旱胁迫降低了苎麻叶绿素含量,降低幅度和显著程度取决于干旱胁迫程度的强弱和干旱持续时间的长短.     

豫北优质大豆产业发展策略

针对豫北地区的大豆生产现状，从气候、土壤、品种、生态因素及市场需求等方面提出了优质大豆的发展策略与途径。     

湖南沅陵4种绿茶品质成分分析

以长沙县高桥相同嫩度茶鲜叶原料采用卷曲形毛尖茶加工工艺制绿茶为对照,分别对沅陵县齐眉翠峰、凤娇碣滩茶、干发茶和军大坪茶4种绿茶的主要生化成分与感官品质进行初步分析。结果表明,沅陵4种绿茶的茶多酚总量28.76%~30.34%,游离氨基酸总量2.35%~3.22%,咖啡碱含量3.00%~3.63%,水浸出物含量37.26%~40.07%,可溶性糖总量5.46%~5.65%,可溶性蛋白含量1.50%~1.74%,类黄酮化合物总量1.16%~1.79%,叶绿素总量1.36%~2.01%,儿茶素总量13.53%~16.20%。与对照相比,4种绿茶的茶多酚、可溶性糖和儿茶素总量均高于对照,除齐眉翠峰外其余3种茶样水浸出物和叶绿素总量均高于对照,除干发茶外其余3种茶样类黄酮化合物总量均高于对照。     

Comparisons of methods of scheduling irrigations of potatoes

Irrigation of Netted Gem potatoes was scheduled during three growing seasons by three methods: (a) when plants displayed first visual symptoms of moisture stress, (b) when indicated by a soil moisture budget involving estimated evapotranspiration, and (c) on the basis of tensiometer readings of soil moisture suction. When the tensiometer method of scheduling was used, the mean yields of tubers were 55.0 and 25.8 cwt/acre (6160 and 2890 kg/ha) higher than those obtained with the other two scheduling methods. Methods did not affect the specific gravity of potatoes. Method (a) scheduled irrigations least frequently. Scheduling by the budget method was not always adequate because it was based on the assumption that the crop extracted water from a constant 4 ft (1.2 m) profile from planting to full vegetative growth. In one year the budget method scheduled the first irrigation earlier than necessary and delayed the second irrigation during a critical period of crop growth. From full vegetative cover to harvest the irrigation schedules were alike for both the budget and tensiometer methods.     

Analysis of nutritional components of eight famine foods of the Republic of Niger

In the western Sahel, indigenous plants become important staples when cereal harvests are inadequate to support populations inhabiting that region of Africa. The purpose of this study was to assess the nutrient content of several of these edible wild plants. The leaves of the following seven plant foods were analyzed: Ziziphus mauritiana, Cerathotheca sesamoides, Moringa oleifera, Leptadenia hastata, Hibiscus sabdarifa, Amaranthus viridi, and Adansonia digitata. The fatty acid, vitamin E, carotenoid, selected mineral and amino acid contents of these plant foods were determined. These same analyses were performed on the fruit of the Adansonia digitata. In quantitative and qualitative terms, Amaranthus viridis was found to be an excellent source of protein. Its amino acid composition compared favorably to that of a World Health Organization (WHO) protein standard. It also contained considerable amounts of the two fatty acids that are essential in humans (linoleic and -linolenic) and a number of minerals including iron, magnesium, calcium and zinc. The leaves of Hibiscus sabdarifa contained an appreciable quantity of protein the composition of which was comparable to the WHO standard. The mineral content of the leaves of this plant was also exceptionally high; noteworthy was its high zinc content. H. sabdarifa also contained significant quantities of the two essential fatty acids. Ziziphus mauritiana was an excellent source of the essential fatty acid linoleic acid and several of the metals including iron, calcium, magnesium and zinc. Its content of other essential nutrients, however, was rather low. In general, Adansonia digitata leaves were nutritionally superior to the fruit of the tree; however, the fruit did contain useful quantities of potassium, phosphorus, zinc and -linolenic acid. The Leptadenia hastata leaves were an especially good source of lutein and -carotene. These data should be useful to the people who inhabit the western Sahel in helping them devise healthy diets during times when cereal staples are in short supply.     

狗牙根诱变后代抗寒性评价

通过电解质外渗法和匍匐茎恢复试验对‘阳江’狗牙根及其12个通过形态鉴定选出的坪用价值高且花序密度低的诱变后代进行抗寒性鉴定。电解质外渗法结果表明:诱变后代间的抗寒性具有较大差异,其叶片半致死温度(LT₅₀)的变异范围为-7.6～-0.2℃(最低值与最大值相差7.4℃);参试材料抗寒性由强到弱依次为M18>M4>M26>M28> M22>阳江>M29>M31>M10>M37>M16>M1>M25,其中,有5个诱变后代抗寒性优于亲本,分别是M18、M4、M26、M28、M22。匍匐茎恢复实验结果表明:诱变后代M1、M22、M26、M31、M25在0℃和-5℃低温胁迫后的恢复生长率都高于亲本,恢复能力均优于亲本;M10、M37、M28在-5℃低温胁迫下,恢复生长能力低于亲本,抗寒性相对较弱,M16和M4在0℃和-5℃低温胁迫下,恢复生长率都低于亲本,抗寒性明显弱于亲本。综合2种方法鉴定结果显示:诱变后代M1、M25的恢复能力较强;M4、M28的叶片抗寒性较好,青绿期较长;M22、M18、M26的叶片抗寒性和匍匐茎恢复能力均较强;M29,M31的叶片抗寒性和匍匐茎恢复能力与亲本相似;M10、M16、M37的叶片抗寒性和匍匐茎恢复能力均较弱,整体抗寒性较弱。     

吉林省平安农业科学院大豆所大豆研究工作报告

1　吉林省平安农业科学院大豆研究工作简介吉林省平安农业科学院大豆研究所 ,设在吉林省长春市西安大路种子大厦内。现有科技人员 6人 ,其中研究员 2人 ,农艺师 2人 ,技术员 2人 ,定向培养研究生 2人。大豆研究所的主要任务是选育稳产、高产、优质及抗病虫大豆新品种 ;同时密切     

巴西橡胶树MADS-box基因家族6个成员的染色体物理定位

MADS-box基因家族广泛分布于真核生物中,巴西橡胶树的MADS-box基因家族主要参与花形态建成,对生殖生长起到重要的调节作用。目前,MADS-box基因家族的26个相关基因已被克隆分析,但它们在染色体上的具体位置还未确定。本研究以巴西橡胶树‘热研7-33-97’品种为材料,将MADS-box基因家族的6个成员（HbAGL8、HbAG15、HbAGL30、HbTT16、HbAP1和HbSVP1）定位在细胞核染色体上,通过双探针荧光原位杂交技术（FISH）对巴西橡胶树MADS-box基因家族的这6个成员在细胞核染色体上进行物理定位分析。结果表明：MADS-box基因家族的6个基因分别位于不同的染色体上,其中HbAGL15、HbAG8、HbAG30和HbSVP1基因定位在第4、5、7和8号染色体长臂上,其信号位点到着丝粒的平均百分距离是11.85、39.71、48.94和6.70;HbTT16和HbAP1基因定位在第1和13号染色体短臂上,其信号位点到着丝粒的平均百分距离是22.19和18.01。本研究结果揭示了巴西橡胶树MADS-box基因家族的6个成员在细胞核染色体上的实际位置,展现家族基因之间的分布特点和连锁遗传关系,不仅丰富了橡胶树分子细胞遗传学信息,也为橡胶树的分子辅助育种和比较基因组学研究提供了分子细胞遗传学的科学理论依据。     

Comparison of two methods of PCNB application for control of Rhizoctonia infection of potatoes

A broadcast application of PCNB (Terraclor) resulted in a reasonably uniform distribution of the chemical in the soil with the concentration decreasing in a linear fashion with increasing depth in the soil profile. A banded application resuluted in a considerably higher chemical concentration at the 4–6 inch depth than at the 0–2 or the 2–4 inch depths. The problem of the lack of uniformity of chemical distribution could probably be solved by altering nozzle placement and size and allow use of the band method of application to minimize grower cost. More complete disking in the case of the broadcast treatment would probably result in a relatively uniform distribution of the chemical but at higher cost to the grower. PCNB application rates of 10, 15 and 25 lbs per acre broadcast and 71/2, 10 and 121/2 lbs per acre in a band significantly reduced the severity ofRhizoctonia infection of Russet Burbank potatoes but did not increase potato yields significantly.     

Prediction of the digestibility of the diet of horses: evaluation of faecal indices

Data from in vivo digestibility trial with four to six horses fed twenty-seven forage-based diets are used to calculate prediction equations for the digestibility of dry and organic matter, based on the crude ash (CA), crude protein (CP) and crude fibre (CF) contents of diets and faeces. The most precise prediction of dry-matter digestibility (r.s.d. = 0.032, R²= 0.80) was derived from a multiple regression including faecal (CP, CF) and dietary parameters (CF). Among faecal parameters, CP was the best single predictor of both digestibility (r.s.d) = 0.040, r²= 0.63) and dietary CP content (r.s.d = 0.028, r²= 0.59). For biological reasons we propose a non-linear model that allows prediction of dry- and organic-matter digestibility from faecal CP Content with reasonable Precision (r.s.d = 0.038, 0.036, r²= 0.65, 0.74, respectively). This will be adequate for many studies, especially for free-living animals in rangelands.