锌对玉米光合特性及抗氧化体系的影响

在玉米拔节期每隔7 d叶片喷施一次0(CK)、2、4、6、8 g/L共5个处理浓度的锌(Zn)叶面肥,连续喷施3次,研究大喇叭口期、抽雄吐丝期及灌浆期微量元素Zn对玉米光合特性及抗氧化系统的影响。试验结果表明,Zn处理有利于提高玉米叶片SPAD值、净光合速率(Pn)、气孔导度(Gs)及蒸腾速率(Tr),降低胞间CO2浓度(Ci),提高叶片固定CO2的能力,从而增强光合作用,促进干物质积累;同时,提高了超氧化物歧化酶(SOD)、过氧化物酶(POD)及过氧化氢酶(CAT)活性,有效降低了丙二醛(MDA)含量,缓解了MDA带来的膜质过氧化伤害。其中在抽雄吐丝期喷施8 g/L锌叶面肥处理,与CK比,Pn、Gs、Tr分别提高25.37%、14.05%、21.72%,Ci降低8.12%;SOD、POD和CAT活性分别提高30.90%、25.65%、20.42%;MDA降低21.18%;SPAD值增加23.34%,干物质积累增加22.33%。综合来看,Zn处理以最高喷施量8 g/L处理效果最好。     

玉米子粒性状种子和母体效应的遗传分析

采用二倍体种子遗传模型及其分析方法,以5个玉米自交系及其间配制的F₁,F₂,BC₁,BC₂世代为材料,研究了7个玉米子粒性状的直接效应、母体效应和细胞质效应。分析结果表明,除粒厚外,各性状的遗传均以母体加性效应为主,种子直接显性效应和母体显性效应较小,细胞质基因对各性状均无显著影响,而环境效应极显著。除粒长的直接显性效应与母体显性效应间的协方差外,直接效应与母体效应间的协方差均较小,且不显著。因此,通过母体植株的遗传表现可对这些性状进行有效的直接选择。S₂₂是改良粒重的优良亲本,而N_O1,N_O2,N_O3对改良粒重不利。各部位子粒百粒重的直接显性效应、母体加性效应、母体显性效应及机误均存在极显著正相关。在自交系选育过程中,直接选择粒较宽的分离类型,容易获得大粒的遗传材料,选择粒厚而宽的亲本组配杂交组合有利于提高F₁粒重。     

Effect of High-Energy Milling on Bioactive Compounds and Antioxidant Capacity in Nixtamalized Creole Corn Flours

Plant Foods for Human Nutrition - This study aimed at evaluating the effect of high-energy milling (HEM) and traditional nixtamalization (TN) on bioactive compounds and antioxidant capacity in...     

玉米杂交种及自交系抗盐性的鉴定

1992～1995年对105份玉米杂交种及自交系进行了抗盐性鉴定．结果表明，玉米杂交种及自交系受盐害后，植株干物质积累速度变慢；黄叶指数增多，干物重下降；根变粗，变短；侧根和根毛减少；节根条数增多；冠/根比值增大；叶细胞透性增大．在105份材料中，抗盐性强的玉米材料有15份，中抗的78份，不抗的12份．     

Alternate Furrow Irrigation with Different Irrigation Intervals for Maize (Zea mays L.)

Abstract

This research was conducted to determine the yield and water-use efficiency of maize under fixed and variable alternate furrow irrigation (fixed AFI, variable AFI) and every furrow irrigation (EFI) at different irrigation intervals in areas with shallow and deep groundwater. In variable AFI, water was applied to the furrow, which was dry in the previous irrigation cycle. The results indicated that even at 4-day irrigation intervals the water needs of maize on a fine textured soil in both areas (with deep and shallow water table) are not met by AFI. The decrease in grain yield due to water stress was mainly due to the decrease in the number of grains per cob and to a lesser extent to the decrease in 1000-grain weight. At the Kooshkak site with shallow groundwater (between 1.31 and 1.67 m), grain yields in AFI at 4- and 7-day intervals were comparable to those obtained in EFI at 7- and 10-day intervals, respectively. This might be due to the contribution of groundwater to the water use of the plant (about 5-10%). In the Badjgah area, with deep water depth, grain yield in AFI at 7-day intervals was statistically lower than that obtained in EFI at 10-day interval. In AFI, a shorter irrigation interval (4-day) may alleviate the water stress and result in no yield reduction compared with that in EFI at 7-day intervals even though water application was reduced. Furthermore, in the area with a shallow water table, AFI at 7-day intervals may be superior to EFI at 10-day irrigation intervals. When seasonal irrigation water is less than 700 mm, it may be preferable to use AFI at 10-day intervals to increase water-use efficiency, especially in areas with shallow groundwater. In general, when water was insufficient for full irrigation, the relative grain yield (yield per unit water applied) of maize under AFI was higher than those under EFI.     

Antimutagenic and Antioxidant Activity of a Selected Lectin-free Common Bean (Phaseolus vulgaris L.) in Two Cell-based Models

Legumes and particularly beans are a key food of Mediterranean diet representing an important source of proteins, fiber, some minerals and vitamins and bioactive compounds. We evaluated the antioxidant and anti-mutagenic effects of a new fermented powder of a selected lectin-free and phaseolamin-enriched variety of common bean (Phaseolus vulgaris L.), named Lady Joy. Lady Joy lysate (Lys LJ) was studied in human erythrocytes and in Saccharomyces cerevisiae yeast cells. The antioxidant and anti-hemolytic properties of Lys LJ, studied in an ex vivo erythrocytes system using the cellular antioxidant assay (CAA-RBC) and the hemolysis test, evidenced a dose-dependent antioxidant activity as well as a significant hemolysis inhibition. Besides, results evidenced that Lys LJ treatment significantly decreased the intracellular ROS concentration and mutagenesis induced by hydrogen peroxide in S. cerevisiae D7 strain. In conclusion, Lys LJ showed both an antimutagenic effect in yeast and a strong scavenging activity in yeast and human cells.

     

玉米幼苗根系对硫酸盐(Na235SO4)亲和性配合力的研究

本文以来源不同的9个玉米自交系及其按双列杂交组成的36个杂交种为材料，研究了玉米幼苗根系对硫酸盐(Na₂³⁵SO₄)亲和性(Km)的配合力。结果表明：m以非加性基因效应较重要，Km与产量间有密切关系。鉴定出可供五米育种中利用的2个自交系“合二”、“292”及具有更广泛适应性和高产特性的3个杂交组合：5005、5022、5030。     

Anthocyanin accumulation,biosynthesis and antioxidant capacity of black sweet corn (Zea mays L.) during kernel development over two growing seasons

In this study, the content changes of anthocyanins levels, antioxidant activities as well as related genes in their biosynthesis pathways of two seasons black sweet corn kernels were determined. Generally, three anthocyanins contents showed similar trend with peak at 10 days after pollination (DAP) in both seasons existing as free forms, and they gradually grew afterwards as kernel matured. Pelargonidin as the leading component was decreased significantly in autumn comparing to contents in summer which may be affected by lower photosynthetically active radiation (PAR) and distinct gene expression levels. CF1, F3H and LAD as the essential genes in flavonoid and anthocyanin biosynthesis had high expression levels indicating higher production of flavonoid and anthocyanin. Black sweet corn (BSC) exhibited good in vitro and cellular antioxidant abilities compared to many fruits and vegetables indicating that BSC could be developed as a substitute food with high anthocyanin profiles and antioxidant capacity.     

Irrigation frequencies and corn (Zea mays L.) yield relation in northern Turkey

A field experiment was conducted during summer season of 2005 at the Research Station (altitude 180 m above sea level, 41 degrees 21' N and 36 degrees 15'E) Faculty of Agriculture, Ondokuz Mayis University, Samsun, Turkey. Experiment consisted of three irrigation levels and a non-irrigation level. Drip irrigation treatments consisted of three soil water deficits in the 90 cm soil profile depth was replenished to field capacity. Irrigation treatments were A: no irrigation, B: irrigation at 50% of available soil water capacity, C: irrigation at 30% of available soil water capacity, D: irrigation at 15% of available soil water capacity. The average seasonal water use values ranged from 257.14 to 285.71 mm in corn treatments. Irrigation frequencies (intervals) significantly affected corn crop yields. The average corn grain yields varied from 7.98 to 29.16 t ha(-1). The treatment D was recorded significantly higher corn grain yield 29.16 t ha(-1) compared to B (21.59 t ha(-1)); C (19.15 t ha(-1)) and A (7.98 t ha(-1)), respectively. According to research results, the maximum corn grain yield was obtained when the corn plants were irrigated at 15% of available soil water capacity to field capacity.     

An evaluation of water-yield relations in maize (Zea mays L.) in Turkey

The objective of this study was to compare the responses of maize (Zea mays L.) to deficit irrigation. A field experiment was conducted during the 1999 and 2000 growing seasons in western Turkey. Irrigation treatments were tested with 100, 70, 50, 30 and 0% replenishment of water depleted at 120 cm soil profile from 100% replenishment treatment at ten days intervals. The irrigation amount ranged between 0 and 323.20 mm in the first year and 0-466.61 mm in the second year of the experiment. Seasonal crop water use values were between 142.19 and 481.91 mm in 1999 and 136.25-599.45 mm in 2000. Average maximum and minimum yields were 10639-10383 kg ha(-1) for full irrigated treatment (I100) and 3750-2136 kg ha(-1) for non-irrigated treatment (I0) in 1999 and 2000, respectively. Water deficit significantly affected maize yield. In both years, yield increased linearly with irrigation applied but the relationship varied from one year to the other. Water Use Efficiency (WUE) ranged from 1.49 to 2.71 kg m(-3), while Irrigation Water Use Efficiency (IWUE) varied from 1.44 to 2.55 kg m(-3) in both years. The yield response factor (ky) relating relative yield decrease to relative evapotranspiration deficit was found to be 0.99 for the data of the two experiments combined. Also, dry matter yields (DM) and leaf area index (LAI) were markedly affected by the irrigation treatments. The finding of this work showed that well-irrigated treatment should be used for maize grown in semi arid regions under no water scarcity.     

硫肥对玉米氮、磷、钾吸收利用影响的基因型差异

以我国夏玉米主产区的34个玉米基因型(6个自交系,4个特用玉米和24个杂交种)为试验材料,通过不同硫肥供应水平的大田试验,分析了硫肥对玉米氮、磷、钾吸收利用的影响.结果表明,施用硫肥促进了玉米对营养元素的吸收,植株氮、磷、钾的积累总量平均比未施用硫肥的对照分别增加6.07%、11.89%和19.31%,肥料利用效率提高.硫肥对氮、磷、钾吸收利用的影响不完全相同,并且存在明显的基因型差异施用硫肥后,自交系氮、磷、钾的收获指数和利用效率均有大幅度提高;杂交种的氮素收获指数和利用效率均有所提高,磷素利用效率下降,但是不同基因型的变化程度差异较大;另有17个杂交种的磷素收获指数降低,10个杂交种的钾素收获指数和14个杂交种的钾素利用效率降低.     

Antioxidant Bioactivity of Extracts from Beach Cast Leaves of Posidonia oceanica (L.) Delile

The marine environment is a generous source of biologically active compounds useful for human health. In 50 years, about 25,000 bioactive marine compounds have been identified, with an increase of 5% per year. Peculiar feature of algae and plants is the production of secondary metabolites, such as polyphenols, synthesized as a form of adaptation to environmental stress. Posidonia oceanica is a Mediterranean endemic and dominant seagrass and represents a biologically, ecologically and geologically important marine ecosystem. Within this study, methanolic and ethanolic extracts were generated from fresh and dried Posidonia oceanica leaves, with the aim to employ and valorize the beach cast leaves. The best yield and antioxidant activity (polyphenols content equal to 19.712 ± 0.496 mg GAE/g and DPPH IC50 of 0.090 µg/µL.) were recorded in 70% ethanol extracts (Gd-E4) obtained from leaves dried for two days at 60 °C and ground four times. HPLC analyses revealed the presence of polyphenols compounds (the most abundant of which was chicoric acid) with antioxidant and beneficial properties. Bioactive properties of the Gd-E4 extracts were evaluated in vitro using fibroblast cells line (HS-68), subjected to UV induced oxidative stress. Pre-treatment of cells with Gd-E4 extracts led to significant protection against oxidative stress and mortality associated with UV exposure, thus highlighting the beneficial properties of antioxidants compounds produced by these marine plants against photo damage, free radicals and associated negative cellular effects. Beach cast leaves selection, processing and extraction procedures, and the in vitro assay results suggested the potentiality of a sustainable approach for the biotechnological exploitation of this resource and could serve a model for other marine resources.     

Effects of Coronatine on Growth,Gas Exchange Traits,Chlorophyll Content,Antioxidant Enzymes and Lipid Peroxidation in Maize (Zea mays L.) Seedlings under Simulated Drought Stress

Abstract

Coronatine is a phytotoxin that affects the accumulation of defence-related metabolites in plants but information on how its effects may be mediated by environmental stress is scanty. An experiment was carried out to determine the changes in growth, gas exchange, relative water content, chlorophyll (Chl) content, antioxidant enzymes and lipid peroxidation in maize (Zea mays L., var. ‘Nongda 3138’) seedlings treated with coronatine under simulated drought stress. Seedlings raised hydroponically in a growth chamber with simulated drought for 8d (long-period drought) or 3d (short-period drought) were treated with or without coronatine at the three-leaf stage. Under the drought condition, treated with coronatine significantly increased the fresh weight and relative water content in leaves of seedling leaves. The increase was accompanied by increased rates of photosynthesis and transpiration, and the maintenance of Chl pigments. Coronatine had no effects on catalase (CAT), guaiacol peroxidase (POD) and glutathione reductase (GR) under normal condition, but it significantly enhanced activities of CAT, POD and GR in stressed seedlings under the long-period drought treatment. Under the short-period drought treatment, the POD and GR activity in the seedlings treated with coronatine were much higher than in those not treated. Malondialdehyde (MDA) increased sharply under drought condition, but treatment with coronatine significantly reduced it by 15%. The total Chl content of leaves under the drought condition was markedly increased by the treatment with coronatine. Seedlings subjected to a short-period drought had reduced water content, but recovered fairly well by the treatment with coronatine with negligible effects on most physiological and biochemical processes. The application of coronatine alleviated the drought stress in maize seedlings and enhanced their tolerance of water stress through changes in physiological and anti-oxidant enzyme activities.     

芽胞杆菌JK05的鉴定及其对香蕉、玉米的促生和生防潜能研究

解淀粉芽胞杆菌、枯草芽胞杆菌和苏云金芽胞杆菌等是重要的有益微生物,被广泛应用于植物病虫的生物防治。前期分离获得1株芽胞杆菌JK05,对其形态、生理生化特征、16S rRNA和gyrA基因序列进行分析,将其鉴定为解淀粉芽胞杆菌植生亚种Bacillus amyloliquefaciens subsp. plantarum。对峙培养实验结果显示,JK05菌株对多种植物病原镰刀菌具有拮抗作用。植物生长促进实验表明,JK05菌株对香蕉和玉米生长具有明显促进作用。盆栽实验结果显示,JK05菌株对香蕉枯萎病具有良好的防治效果。采用特异引物对JK05菌株基因组DNA进行PCR扩增,其可扩增到表面活性素（surfactin）、丰原素（fengycin）、伊枯草菌素A（iturin A）等抗生素合成基因。综上,JK05菌株具有良好的生防潜力,有望应用于生物农药和微生物肥料。     

Phytochemicals and Antioxidant Capacity of Tortillas Obtained after Lime-Cooking Extrusion Process of Whole Pigmented Mexican Maize

The lime-cooking extrusion represents an alternative technology for manufacturing pre-gelatinized flours for tortillas with the advantages of saving energy and generation of null effluents. The phytochemical profiles (total phenolics, anthocyanins) and antioxidant activity of four different types of whole pigmented Mexican maize [white (WM), yellow (YM), red (RM), blue maize (BM)] processed into tortillas were studied. The lime-cooking extrusion process caused a significant decrease (p?相似文献   

不同株型高产玉米蒸腾作用的研究

在夏玉米亩产吨粮的研究中,测定了平展型玉米各单40和紧凑型玉米掖单6号大喇叭口期和吐丝期不同叶位不同密度的蒸腾速率(Tr)及其日变化.结果看出:鲁单40的Tr高于掖单6号,大喇叭口期Tr高于吐丝期.玉米前期上部展开或即将展开的叶Tr较高,后期中部和上部较高.Tr的日变化为单峰曲线,中午最高.增加种植密度使Tr减少,鲁单40玉米的Tr受密度影响较大.     

两种方法对几个玉米自交系遗传特性及育种潜势的比较分析

试验采用7个自选系、7个外引系、外杂选系和按NCⅡ组配的49个杂种F1组合为研究材料.应用混合线性模型、配合力两种分析方法对单株粒重的遗传方差和遗传力的分析结果进行了比较,并在此基础上对LUP两种效应值与两种配合力效应值进行了比较分析.结果表明:混合模型分析只揭示了显性和加加上位性效应;而配合力分析是在加-显遗传模型基础上进行的,只能揭示加性和显性效应.两种分析方法所得各遗传方差分量与遗传力都基本一致.分析LUP所预测的单株粒重的各遗传效应值表明:LUP加性效应各亲本系列(包括亲本效应)与一般配合力大小顺序完全一致;LUP的显性效应与各组合的特殊配合力及超对照优势均呈极显著的正相关关系(r=0.70和r=0.93),特殊配合力与超对照杂种优势的相关系数(r=0.56)也达到极显著水平。     

Mixing trait-based corn(Zea mays L.) cultivars increases yield through pollination synchronization and increased cross-fertilization

Abiotic stress such as high temperature at flowering is one of many conditions reducing yield of corn(Zea mays L.). Mixing corn cultivars with diverse functional traits increases within-crop diversity and provides a potential means of mitigating yield losses under stress conditions. We conducted a three-year field study to investigate the effects of cultivar mixtures on kernel setting rate, pollen sources, and yield.This study consisted of six treatments, including two high temperature-tolerant(...     

Transition from vitreous to floury endosperm in maize (Zea mays L.) kernels is related to protein and starch gradients

Relationships between kernel vitreousness and proteins and starch partitioning to the floury and vitreous regions of the endosperm were monitored in a set of 13 maize inbred lines. Decrease of protein contents from the vitreous to the floury endosperms were mainly assigned to α-zeins. Using Raman microspectroscopy, we observed a protein gradient from the periphery to the center of endosperms that well fitted with the inverse relationships between vitreousness and protein content of the vitreous and floury regions. In addition, Raman microspectroscopy highlighted an increase of starch crystallinity from the periphery to the center of the maize endosperms. This agrees with the higher amylose and associated lipid contents within starches of vitreous than in those of floury endosperms. Finally, starch granules from vitreous regions displayed more channels than the floury ones. These channels contain proteins that might favor adhesion of proteins to starch granules or granule–granule contacts to form the close packing of the vitreous endosperm. Therefore transition from vitreous to floury endosperm is at least the result of both protein and starch gradients. These gradients are probably associated with metabolic gradients that have been observed during endosperm development.