玉米品种更替过程中品种群体整齐度的变化

选用1950~2010年具有代表性的11个品种,设置4个种植密度,测定株高、穗位高、果穗长、穗粗、穗行数、行粒数指标的整齐度。结果表明,随着品种的更替,株高、穗位高、穗长、穗粗、穗行数、行粒数的整齐度明显提高,株高整齐度的提升最为突出。随着种植密度的提高,玉米的群体整齐度下降,现代品种对增密响应更加明显;同等密度条件下,现代品种的群体整齐度均高于早期品种。相关分析表明,玉米产量与株高、穗位高、穗长、穗粗、穗行数、行粒数性状的整齐度具有明显正相关关系。玉米产量提升过程与品种的群体整齐度同步,株高、穗位高整齐度是最为直观的评价指标,通过品种改良和种植技术的改进提高群体的整齐度是进一步提升产量的技术途径之一。     

玉米田间整齐度、单株生产力和群体产量的相关分析

通过8112×关17-1、晋单27两个玉米品种六种密度试验的各生育期株高及成株期穗部性状调查,用量化指标对玉米田间整齐度、单株生产力和群体产量之间的关系进行了分析。结果表明:玉米田间整齐度在玉米生育进程中有逐渐提高的趋势;株高整齐度与单株生产力呈极显著正相关,8112×关17-1的相关系数r为0.9274,晋单27的相关系数r为0.9214,二者均随密度的提高而降低;群体产量首先服从于密度的压力,不同的品种,其密度极限值不同,8112×关17-1的适宜密度为6.75万株hm²,晋单27的适宜密度为6万株hm²;在相同密度条件下,整齐度与群体产量呈极显著正相关,相关系数r=0.9665^**。     

不同纯度玉米群体株高、光分布和产量的比较研究

研究了不同纯度条件下沈农87品种玉米群体的田间性状及产量。结果表明:纯度与群体株高呈极显著正相关,处理间差异显著;随着纯度降低,株高整齐度下降,同一冠层高度透光率增加。产量与纯度为极显著正相关关系,纯度每降低1%,产量下降0.6%～0.7%。     

密度及施氮量对短季直播棉花产量和纤维品质的影响

在油后短季直播条件下,研究了种植密度、株行距配置、施氮量对于棉花群体产量性状和纤维品质各指标的影响。试验结果表明:施氮量对于提高棉花群体成铃数具有重要意义。密度对于提高籽棉产量和皮棉产量具有至关重要的作用。三种因素分别对籽棉产量和皮棉产量有极显著影响,交互作用对产量的提高也有极显著影响。施氮量180 kg/hm2处理的群体具有较高的上半部纤维长度、伸长率和断裂比强度。高密度比低密度群体具有相对高的整齐度指数;等行距处理比宽窄行处理整齐度指数高。     

植株田间分布均匀度对夏玉米植株性状、田间光照和杂草的影响

采用双因素裂区试验对夏玉米生长期的田间光照、田间杂草、产量及构成、LAI、根系等特性进行了研究,明确植株田间分布均匀度对夏玉米的生态效应影响。结果表明:随着植株田间分布均匀度的提高,玉米产量、收获穗数、穗粒数、最大LAI提高,冠层内的光截获增加,光透射减少;同时,杂草的种类、数量和鲜重均有减少趋势。随种植密度的增加,杂草减少效应更明显。低均匀度处理的穗位整齐度和株高整齐度较小,空株率较大,提高密度可使株高整齐度得到改善;低密度高均匀度处理的茎较粗;根数对密度和均匀度反应不明显。因此,适当提高种植均匀度和密度有利于提高玉米群体质量,有效利用自然资源,抑制杂草生长,改善玉米生长的生态环境,从而提高产量。     

玉米株高整齐度与穗部性状关系的研究

本文通过对玉米株高整齐度与穗部性状的相关分析，明确了玉米株高整齐度与单株产量、穗长及每行粒数呈极显著的正相关关系，而与秃尖长度存在着极显著的负相关关系．因而，栽培上必须把株高整齐度作为衡量玉米群体生育均衡性的指标给以足够的重视．     

提高玉米群体整齐度的研究

本文通过对种子子粒大小、株间组合、栽后返青期三个因素的研究,探讨了不同因素对玉米个体的影响,明确了群体整齐度与单株产量的关系。因而,在栽培措施上提出了一套玉米群体均衡生长的技术指标。     

湘杂棉8号不同密度下性状及产量品质表现

对不同密度下湘杂拂8号农艺性状、产量构成和纤维品质进行研究。结果表明：果枝数、果节数、单株成铃数、成铃率均随着密度的增加而逐渐降低;12000株,hm^2处理的籽棉、皮棉产量,成铃数／hm^2最低。30000株/hm^2产量最高,39000株/hm^2次之,适宜密度为301300—39000株/hm^2;各处理间棉圩维平均长度、比强度、伸长率差异不显著,21000株／hm^2处理的整齐度最高,为85．19％。12000株/hm^2处理整齐度最低,为84．38％。     

大豆整齐度与产量的关系

试验证明，在同一密度同一配置方式下，大豆株高整齐度与产量呈正相关。大豆株高整齐度对产量的影响服从配置方式和对产量的影响。无限结英习性大豆株高整齐度最高，亚有限次之，有限最低。     

种植密度对先玉335群体子粒灌浆特征的影响

2008年在高产田内较大密度处理范围(22500、45000、67500、90000、112500株/hm2)分析玉米品种先玉335群体子粒灌浆特征及其与产量的关系。结果表明:高产密度群体(90 000株/hm2)产量显著高于低密度(22500株/hm2)和超高密度(112500株/hm2)群体。各密度下群体子粒灌浆过程均可用Logistic方程模拟。高产密度的群体子粒平均灌浆速率、最大灌浆速率显著高于低密度、超高密度。不同密度群体子粒活跃灌浆期差异不显著。相关分析表明,群体子粒灌浆速率是影响产量的主要因素。进一步分析表明,对产量影响最大的是粒重渐增期的群体子粒灌浆速率,其次为线性灌浆期的群体子粒灌浆速率,后者与前者呈显著正相关关系。因此,提高粒重渐增期的群体子粒灌浆速率对提高群体产量尤为重要。     

Pharmacokinetics of Marine-Derived Drugs

Marine organisms represent an excellent source of innovative compounds that have the potential for the development of new drugs. The pharmacokinetics of marine drugs has attracted increasing interest in recent decades due to its effective and potential contribution to the selection of rational dosage recommendations and the optimal use of the therapeutic arsenal. In general, pharmacokinetics studies how drugs change after administration via the processes of absorption, distribution, metabolism, and excretion (ADME). This review provides a summary of the pharmacokinetics studies of marine-derived active compounds, with a particular focus on their ADME. The pharmacokinetics of compounds derived from algae, crustaceans, sea cucumber, fungus, sea urchins, sponges, mollusks, tunicate, and bryozoan is discussed, and the pharmacokinetics data in human experiments are analyzed. In-depth characterization using pharmacokinetics is useful for obtaining information for understanding the molecular basis of pharmacological activity, for correct doses and treatment schemes selection, and for more effective drug application. Thus, an increase in pharmacokinetic research on marine-derived compounds is expected in the near future.     

La pourriture fongique des tubercules de pomme de terre en atmosphère contrôlée

Résumé Fusarium culmorum et, dans une moindre mesure,F. avenaceum, F. sambucinum, Colletotrichum coccodes etCylindrocarpon sp. ont été isolés de tubercules entreposés en atmosphère contr?lée (AC) et atteints de pourriture grave. Des expériences d'inoculation de tubercules avec 10 espèces ou variétés fongiques et conservation en AC à 8 et 10°C ont montré que: 1) les champignons non pathogènes en atmosphère normale (ex.:Cylindrocarpon sp.) le devenaient en AC, 2) ceux qui étaient faiblement pathogènes en atmosphère normale étaient nettement plus virulents en AC (ex.:F. culmorum), 3) les espèces ou variétés virulentes en conditions d'air normales (Fusarium sulphureum etPhoma exigua var.foveata) ne provoquaient pas de pourriture plus grave en AC et leur activité pouvait même être légérement freinée.

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Summary The extensive rotting of tubers which occurred during storage trials in controlled atmospheres has led to a mycological and pathological study of the rots. The most frequently isolated species wasFusarium culmorum althoughF. avenaceum, F. Sambucinum, Coletotrichum coccodes and aCylindrocarpon sp. were also present. Tubers of cvs Bintje and Ulla were inoculated with 19 isolates of 10 fungal species or varieties associated with rotting of stored tubers (Table 1). The tubers were incubated at 8 or 10°C in normal or controlled (2% O₂:1% CO₂, 2% O₂:6% CO₂, 2% O₂:12% CO₂, 6% O₂:6% CO₂) atmospheres and the extent of rotting was determined a month later (Tables 2 and 3 and Fig. 2). Species which were weakly virulent in a normal atmosphere (variousFusarium spp. andPhoma exigua var.exigua) were clearly more aggressive in the controlled atmosphere and this was especially evident in the case ofF. culmorum. Species ot pathogenic in a normal atmosphere under experimental conditions (Colletotrichum coccodes, Cylindrocarpon sp.,Phoma eupyrena) caused rotting in the controlled atmosphere. The two species which were virulent in a normal atmosphere (F. sulphureum andP. exigua var.foveata) were also virulent in the controlled atmosphere and in some cases the extent of rotting was even less. As a general rule, rotting caused by weakly virulent fungi was greater in both cultivars in the controlled than in a normal atmosphere.

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Zusammenfassung Eine starke F?ulnis von in Kontrotrollierter Atmosph?re gelagerten Kartoffelknollen veranlasste eine mykologische und pathologische Untersuchung. Der am h?ufigsten isolierte Pilz warFusarium culmorum. F. avenaceum, F. sambucinum, Colletotrichum coccodes undCylindrocarpon sp. wurden ebenfalls bestimmt. Neunzehn St?mme von 10 Pilzsorten oder-Arten welche bei Lagerf?ulnis vorkommen (Tab. 1) wurden auf Knollen der Sorten Bintje und Ulla inokuliert. Die Lagerung wurde bei 8 oder 10°C under Normalbedingungen oder kontrollierter Atmosph?re durchgeführt (2% O₂:1% CO₂, 2% O₂:6% CO₂, 2% O₂:12% CO₂, 6% O₂:6% CO₂). Der F?ulnisgrad (Abb. 1) wurde nach einem Monat bonitiert. Die Ergebnisse sind in den Tabellen 2 und 3 dargestellt und in der Abb. 2 illustriert. Unter in Normalbedingungen nur schwach virulente Arten (verschiedeneFusarien undPhoma exigua var. exigua) waren deutlich aktiver in kontrollierter Atmosph?re. Dies was besonders der Fall fürF. culmorum. Pilze, die im Versuch unter Normalbedingungen nicht pathogen waren (Colletotrichum coccodes, Cylindrocarpon sp., Phoma eupyrena), haben unter kontrollierter Atmosph?re Sch?den verursacht. Hingegen werden die beiden unter Normalbedingungen sehr pathogenen Arten (F. sulphureum undP., exigua var.foveata), durch kontrollierte Atmosph?re wenig beeinflusst. Es wurde sogar in einigen F?llen eine gewisse Verringerung des F?ulnisbefalls beobachtet. Ganz allgemein haben die getesteten kontrollierten Bedingungen die Entwicklung der Pilzf?ulnis an beiden Kartoffelsorten gef?rdert, speziell durch Pilzarten, welche unter Normal-bedingungen wenig Sch?den verursachen.

     

Marine Pharmacology in 2016–2017: Marine Compounds with Antibacterial,Antidiabetic, Antifungal,Anti-Inflammatory,Antiprotozoal, Antituberculosis and Antiviral Activities; Affecting the Immune and Nervous Systems,and Other Miscellaneous Mechanisms of Action

The review of the 2016–2017 marine pharmacology literature was prepared in a manner similar as the 10 prior reviews of this series. Preclinical marine pharmacology research during 2016–2017 assessed 313 marine compounds with novel pharmacology reported by a growing number of investigators from 54 countries. The peer-reviewed literature reported antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral activities for 123 marine natural products, 111 marine compounds with antidiabetic and anti-inflammatory activities as well as affecting the immune and nervous system, while in contrast 79 marine compounds displayed miscellaneous mechanisms of action which upon further investigation may contribute to several pharmacological classes. Therefore, in 2016–2017, the preclinical marine natural product pharmacology pipeline generated both novel pharmacology as well as potentially new lead compounds for the growing clinical marine pharmaceutical pipeline, and thus sustained with its contributions the global research for novel and effective therapeutic strategies for multiple disease categories.     

Effects of Micronutrient Deficiencies on Human Health: Its Status in South Asia

SUMMARY

Vitamin A, iodine, and iron deficiencies affect large numbers of people worldwide. A deficiency of one or more of these micronutrients adversely affects the physical and mental abilities of humans. South Asia contains a high percentage of these individuals, not just because of its large population, but also the prevalence of deficiency is higher there than in many other parts of the world. The reasons for the high rates of deficiency in South Asia are many, but they include inadequate availability of micronutrient-rich foods, sub-optimal dietary habits, and high rates of infection. Across the region, national plans vary from (a) increasing availability of appropriate foods, (b) introducing new dietary behaviors, (c) improving health status, and (d) directly addressing deficiency through intervention programs. The extent to which each of the countries is making progress toward the goals of these plans can help in understanding the priorities for future efforts to address micronutrient malnutrition. This article discusses the adverse effects of micronutrient deficiencies in humans with special reference to South Asia.     

In vitro reproduction in the annual pasture legumes subterranean clover (Trifolium subterraneum L.) and French serradella (Ornithopus sativus Brot.)

Pasture legumes are important components of both mixed farming rotations and permanent pastures in temperate climates. Breeding of two widely sown pasture legumes, subterranean clover (Trifolium subterraneum L.) and French serradella (Ornithopus sativus Brot.), is constrained by the long generation cycle, typically enabling only one generation per year. We hypothesized manipulation of culture medium and conditions would enable the development of a laboratory‐based protocol for in vitro reproduction in subterranean clover and French serradella. In vitro flowering and viable seed set was induced from both species. For subterranean clover, the most effective treatment was culturing on modified MS medium with 1 μm kinetin and 0·1 m sucrose under a 100 μmol m^?2 s^?1 light intensity and continuous photoperiod. For French serradella, culture on a hormone‐free B5 medium with 5 mm NH₄Cl and 0·1 m sucrose under a 100 μmol m^?2 s^?1 light intensity and 20 h photoperiod was optimum. It is expected this technique will have application in accelerating generation turnover within breeding programs, for the study of factors influencing flowering in pasture legumes, and for the propagation of valuable yet enfeebled plants such as embryo‐rescued hybrids.     

Management of Soil Micronutrient Deficiencies in the Rice-Wheat Cropping System

Summary

Within the last three decades, the rice-wheat cropping system has triggered, and with time, aggravated soil micronutrient deficiencies in the Indo-Gangetic Plains (IGP). This has largely been due to the shift from an earlier rice and wheat monoculture with low yielding, long duration indigenous varieties, to an intensive rice-wheat rotation cropping system with short duration modern high yielding varieties on the same piece of land. The problems related to micronutrient deficiency in the IGP are more due to the size of its available pools in the soil rather than its total contents and are greatly influenced by crop management, or rather its mismanagement. Deficiency of zinc is widespread in the IGP, but with the extensive use of zinc sulfate, zinc deficiency has reduced in some areas of the region. Meanwhile, the deficiency of Fe, Mn and B has increased in the IGP. Deficiency of Cu and Mo is location specific and can limit rice and wheat yields. The adoption and spread of the rice-wheat system in permeable coarse textured soils, particularly in the western IGP, not only caused iron deficiency in rice but also resulted in the emergence of manganese deficiency in wheat. In highly calcareous and acidic soils, boron is the next limiting micronutrient in crop production after zinc. Bumper rice and wheat harvests in the past decade, the declining use of organic manures in the region and except for the widespread use of zinc sulfate, a general lack of awareness amongst farmers on micronutrient deficiency problems has contributed to micronutrients limiting rice and wheat yields in the IGP. Approaches to alleviating micronutrient deficiencies include matching the crop removals of the micronutrients with its replenishments through their respective external carriers, supplementation through organic sources and mobilization/utilization through cultivation of micronutrient efficient crop cultivars. Identification of efficient micronutrient carriers and finding the optimum rate, mode and time of its application is important in ameliorating the micronutrient deficiencies. This article reviews the extent of micronutrient deficiency and discusses various management options available to reduce micronutrient deficiency induced crop yield reduction for rice and wheat in the Indo-Gangetic Plains.     

Irrigation but not N fertilization enhances seedhead density in plains rough fescue ( F estuca hallii)

Plains rough fescue ( F estuca hallii) is an important forage grass species in western Canada. Seed for use in pastures and ecological restoration is in high demand but supply is limited because F. hallii is an erratic seed producer. Seed producers require an understanding of the factors that influence flowering and seed set in this species. The aim of this study was to assess the effect of irrigation and nitrogen fertilization on the flowering and growth of F. hallii in a native rough fescue prairie in Alberta, Canada. Irrigation had a strong positive effect on seedhead density, whereas fertilization had limited effects on growth and reproduction of F. hallii. These results demonstrate that under field conditions, available moisture is likely to be a key factor driving flowering and seed production in F. hallii.     

Marine Drugs Regulating Apoptosis Induced by Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL)

Marine biomass diversity is a tremendous source of potential anticancer compounds. Several natural marine products have been described to restore tumor cell sensitivity to TNF-related apoptosis inducing ligand (TRAIL)-induced cell death. TRAIL is involved during tumor immune surveillance. Its selectivity for cancer cells has attracted much attention in oncology. This review aims at discussing the main mechanisms by which TRAIL signaling is regulated and presenting how marine bioactive compounds have been found, so far, to overcome TRAIL resistance in tumor cells.     

Estimation of lucerne yield stability for enabling effective cultivar selection under rainfed conditions

Evaluation of crop and forage yield stability is of increasing relevance in the context of current and recent environmental changes but, in contrast to other field crops, there are no published systematic analyses among forage crops in Europe. A study of stability performance was conducted with 13 Czech cultivars of lucerne at four locations over a 2‐year period with the following aims: (a) to evaluate yield stability of varieties across different environments and (b) to calculate measurable benefits of variety selection in relation to the specific environment. The cultivar Vlasta was identified as the highest yielding cultivar (annual yield 16.0 t DM/ha), whereas the lowest yielding cv. Magda, Tereza and Oslava averaged around 14.9 t DM/ha. Effect of genotype × environment interaction (G × E) was two times higher than for genotype alone. Additive main effects and the multiplicative interaction (AMMI) model showed that the highest yielding cultivars may not be stable across environments. This study demonstrated further that significant yield improvement could be detected, even among a relatively homogenous group of domestic cultivars, and this was driven mainly by site productivity: the improvement was +10% in low‐yielding sites, compared with +3% in high‐yielding sites. Results highlight that advanced agronomy should also consider stability parameters such as AMMI stability value or superiority measures for forage crops in response to the challenges associated with climate change.     

Biochemical and morphological characterization of potato clones differing in their resistance to late blight

Summary Morphological and biochemical parameters that could be involved in resistance to late blight were studied in non-infected and in infected potato hybrids resulting from a cross betweenSolanum phureja, resistant toPhytophthora infestans, and a susceptibleSolanum tuberosum. Some morphological differences between resistant and susceptible hybrids, indicating a positive correlation between stem diameter and phloem thickness in the stem and resistance toP. infestans, were observed. The lignin content in the leaves of the resistant hybrid rose upon infection byP. infestans. In the leaves of the susceptible hybrid, a diminution of the lignin content could be observed upon infection byP. infestans. In the same context, peroxidasic activity raised upon infection byP. infestans in both resistant and susceptible hybrids. Further characterization of the hybrid clones based on the polymorphism of peroxidases was attempted using isoelectric focusing.