广西蔗区检测发现检疫性病害甘蔗白条病

为明确2016年在广西北海、来宾、百色蔗区发现的疑似甘蔗白条病症状蔗株致病病原。利用白条黄单胞菌特异性引物XAF1/XAR1对采自这3个蔗区的62份疑似病样进行PCR检测鉴定。鉴定结果表明：62份疑似病样都能够获得约600 bp的特异性片段,所得序列完全一致大小均为608 bp（GenBank登录号：KY315183--KY315203),其与白条黄单胞菌raxB1基因核苷酸序列（GenBank 登录号：FP565176）一致性为100%,在系统进化树中处于同一分支。田间调查结果显示：甘蔗品种‘桂糖46号’、‘桂糖06-2081’对于白条黄单胞菌高度感病,病株率一般为18%~50%,严重田块高达100%;染病严重蔗株全叶枯萎,茎的节部长出许多侧芽,侧芽叶片具白色条纹,造成大幅度减产减糖。本研究在广西蔗区检测发现由白条黄单孢菌引起的检疫性病害甘蔗白条病。     

Screening the Spanish Barley Core Collection for disease resistance

The Spanish Barley Core Collection comprises 159 landrace-derived inbred lines and 16 cultivars adapted to Southern European conditions. The collection was screened for resistance to powdery mildew ( Blumeria graminis ), scald ( Rhynchosporium secalis ), leaf rust ( Puccinia hordei ), net blotch ( Pyrenophora teres f. teres ), Barley yellow dwarf virus (BYDV) and Barley mild mosaic virus (BaMMV). Resistance to powdery mildew was outstanding, with 58 lines presenting mean overall resistance, among them seven landrace-derived lines resistant to all seven isolates tested. About 26% of the Spanish lines were resistant to scald. Resistance to leaf rust and to net blotch was scarce, though a few accessions showed resistance levels as good as the checks. Thirteen accessions (12 Spanish) were totally resistant to BaMMV and c. 20% of accessions showed moderate tolerance to BYDV. Landrace-derived lines from the Mediterranean Coast and Southern regions of Spain were the most resistant to powdery mildew and leaf rust, but the most susceptible to viruses. Potential sources of resistance might be preserved in some accessions subjected to selective pressure in the region of origin.     

垄作栽培对啤酒大麦产量和品质的影响

探讨在等量灌水条件下垄作栽培对啤酒大麦产量和品质的影响。结果表明：（1）垄作栽培生育期长于传统平作栽培,单株穗数低于传统平作栽培,经济系数高于传统平作栽培,株高、穗粒数、产量影响趋势不一致,品种之间存在差异。（2）原麦品质：垄作栽培与传统平作栽培籽粒千粒重之间差异不显著,蛋白质含量之间差异显著,粒筛选率之间差异极显著水平,千粒重、蛋白质含量、筛选率均降低。（3）麦芽品质：垄作栽培麦芽蛋白质含量均较传统平作栽培降低,麦芽细粉浸出物、β-葡聚糖、a-氨基氮、a-淀粉酶、糖化力、可溶性氮之间差异不显著,库值含量之间差异达显著水平,但影响趋势不一致,品种之间存在差异。     

Effects of Competition upon the Productivity of White Clover-Perennial Ryegrass Mixtures. Seasonal Trends

Seasonal trends among those characters, affecting productivity in white clover-perennial ryegrass mixtures were investigated m a set of 20 mixtures using clover material derived from a. diallel cross between four contrasting white clover varieties. The productivity and associated vegetative characters showed the familiar pattern of high grass production in spring, and early summer, with a secondary peak of growth in autumn, whilst clover achieved its; highest productivity levels in mid-summer. A significant linear relationship was established between clover canopy height and ryegrass canopy height for all 20 mixtures. Although no significant heterogeneity was detected among the fitted regression lines, there was an indication that the linear regressions provided a better fit to the data in those mixtures having ‘Skomer’ as the grass companion. An analysis of the differences in canopy height between ryegrass and clover indicated that the ‘Menna ‘/’S. 23’ mixture had a reduced seasonal range compared to the other mixtures. Consequently, during the early par', of the growing season, when the tallest canopies occurred and. when shading of clover by the grass was most intense, the difference in canopy height between ‘S. 23’ and ‘Menna’ was relatively low. There was a pronounced effect of grass companion upon canopy height difference, due entirely to the taller growth habit of the ‘Skomer’ ryegrass variety, These interrelationships are discussed briefly in the context of improving the productivity of white clover-perennial ryegrass mixtures.     

Effects of Competition upon the Productivity of White Clover-Perennial Ryegrass Mixtures. Analysis of and Interrelations between Characters

A diallel crossing programme amongst tour contrasting white clover varieties was used to generate material for studying the interrelationships amongst those characters which affect the productivity of white clover- perennial ryegrass mixtures under a cutting-only management regime. Such a regime favoured clover growth. All the clover characters exhibited strong positive correlations with mixture yield. However, this combination of clover characters did not promote growth of the grass companion. For this a low growing variety with a dense stolon network appeared preferable. Path analysis indicated that differences existed between the two companion grass varieties used for this experiment in their upon clover characters.     

The Effect of Inoculum Pressure, Germplasm Selection and Environment on Spring Barley Cultivar Mixtures Efficacy

A range of mixtures including one set made from cultivars grown in the UK and one from cultivars grown in Poland, were included, along with their component cultivars, in nine trials at Scottish Crop Research Institute, Dundee, UK or at the Experimental Plant Breeding Station of the IHAR, Baków near Kluczbork, Poland, over five seasons. The effects of inoculum pressure, plot size, fertiliser level and germplasm on mixture efficacy were investigated. In the four trials where inoculum pressure was controlled, mixtures reduced infection more at lower inoculum pressures, but this did not translate into yield benefit. Smaller plots increased mildew in monocultures but not mixtures. Fertiliser levels increased mildew levels but did not affect mixture efficacy. There were large differences between both Polish and UK germplasm, and between Polish and UK trial sites, but the performance of the mixtures compared with their respective monoculture components was similar within both germplasm groups and trial sites. Mixtures reduced lodging and affected plant height and heading date. The advantages of mixtures for improving yield, reducing fungicide applications and improving agronomic characteristics was demonstrated and there seems to be great potential for their further improvement and exploitation. This revised version was published online in August 2006 with corrections to the Cover Date.     

Effects of Competition upon the Productivity of White Clover-Perennial Ryegrass Mixtures. Genetic Analysis

A diallel cross amongst four contrasting white clover varieties was used to provide genetic information on those characters which affect the productivity of white clover-perennial ryegrass mixtures when grown under a cutting-only management regime. Generally speaking those characters recorded on the clover families and in mixtures exhibited highly significant additive and non-ad dative genetic effects, though for1 sortie characters the latter could not be ascribed solely to dominance effects. For two of the clover characters, stolon and leaf number, the genetic picture was radically altered in mixtures by the effects of inter-specific competition Pseudo-genetic effects were also detected for the grass characters, bur it was suggested that the two ryegrass varieties used here were exhibiting phenotypic plasticity. As a group the four intra-varietal crosses performed significantly better than the six intra-varietal crosses for all clover and mixture characters. Only one of the inter-varietal crosses had significantly positive specific combining ability effects for most characters and that was between the two long established varieties ‘S. 184’ and ‘S. 100’. The implications of these results for the breeding of white clover varieties for use in mixtures are briefly discussed.     

小麦二系混合种的产量优势及其成员品种的生态组合力研究

利用3个耐盐小麦品种和4个普通丰产品种,按不完全双列混配法等量混配成12个二系混合种,在花碱地上研究了小麦二系混舍种的混合优势及其7个成员品种的生态组合力。结果表明,小麦二系混合种的混合优势普遍存在,且组合间的混合优势差异显著,平均优势幅度为—4.5％～20％,超亲优势为—12.3％～16.8％;生态组合力分析表明,成员品种间生态组合力差异显著,同一成员品种在不同的环境中生态组合力表现亦有差异。因此,在混配小麦二系混合种时,应选择生态组合力好的成员品种进行混配,这样会选出混合优势强的高产二系混合种。     

云南高原青稞生产存在问题及提高产量途径

本文对云南高原青稞生产存在的问题及提高产量途径做出了较全面的论述,旨在进一步提高我省青稞的产量和品质,推动云南省青稞生产及青稞产业的迅速发展,并为加快实施生物资源创新工程、农业产业结构调整和建设绿色经济强省做出贡献。     

Effects of Fungicide on Grain Yield of Barley Grown in Different Cropping Systems

The effect of fungicides and their combination on yield of barley under different nitrogen, slurry and tillage treatments was investigated at Hohenschulen Experimental Station near Kiel, Germany in 1991–97. Various fungicide treatments (no fungicide, and treatment with stem, leaf and ear fungicides and combinations of these), two nitrogen levels (120 and 240 kg N ha⁻¹), two tillage systems (minimum and conventional tillage) and four slurry applications (no application, and autumn, spring and autumn plus spring applications) were used. On average, fungicide application increased barley yield by 1.1 t ha⁻¹. The fungicide treatments could be classified into four types: (1) fungicides against stem diseases, which slightly increased yield by 0.25 t ha⁻¹, very similar to the results for the untreated control; (2) leaf fungicides and ear fungicides applied separately, and fungicides against a combination of stem and leaf diseases, which increased yield by 1.0 t ha⁻¹ on average; (3) fungicides against a combination of ear and stem diseases, which increased the yield by 1.22 t ha⁻¹, and (4) fungicides against a combination of leaf and ear diseases and a combination of stem, leaf and ear diseases, which increased yield by 1.59 t ha⁻¹ on average. The effects of fungicide on the yield were modified by crop husbandry. It can be concluded that application of fungicides against a combination of leaf and ear diseases could increase barley yield and reduce yield variation.     

Yield Comparison of Within Row Mixtures, Between Row Mixtures, and Composites of Spring Faba Bean Cultivars

The performance of three spring faba bean ( Vicia faba L.) cultivars Stella, Danas, and Minden in monocultures were compared with mixtures of Stella + Minden, and Danas + Minden sown as within row mixtures, alternate row mixtures, and as composites.
Mixtures of both cultivar combinations, whether mechanical or composites, had net increases in seed yield per plot ranging from 10.5 % to 20 % above the means of the component cultivars grown in monoculture. Cultivars grown in mixtures in alternate rows had slightly greater seed yield than when they were grown alternately within rows. A further yield enhancement was obtained from growing composites.
Data for total plant dry weight were similar to those for seed yield. The number of podded nodes per plant was the major yield component responsible for the increased yields of the component cultivars in mixtures. The ecological aspects of these results are discussed.     

贮藏期间红富士苹果虎皮病发病因素分析及应对措施

综述与分析引起红富士苹果贮藏后期发生虎皮病的主要因素和发病机理,针对苹果采前与采后生产实际,提出相应的预防措施,以期达到防止红富士苹果虎皮病的发生,降低发病率和病情指数的目的。     

Yield and Osmotic Adjustment Capacity of Barley Under Terminal Water-Stress Conditions

This paper reports the influence of the osmotic adjustment capacity and turgor potential (TP) on tolerance to drought in 12 cultivated genotypes, six breeding lines and six cultivars of barley (Hordeum vulgare L.) under terminal water‐stress conditions. When the crops reached the flag leaf stage, half of the experimental plots in which they were grown were submitted to water stress treatment and the remainder maintained under optimal irrigation conditions. Differences were seen in the osmotic adjustment, relative water content (RWC) and water potential (WP) of the different genotypes. Two of the breeding lines showed the greatest osmotic adjustment capacities, maintaining their TPs better than the other genotypes studied. A positive, significant correlation was found between yield and osmotic adjustment capacity, RWC and WP under water‐stress conditions. Osmotic adjustment capacity and TP were linearly related, indicating that as water stress increases osmotic adjustment favours the maintenance of higher TPs. Significant correlations were found between osmotic adjustment capacity and grain filling rate and grain yield. Under conditions of terminal water stress, yield was negatively correlated with the number of days to ear emergence; no correlation was found between osmotic adjustment capacity and earliness. Early ear emergence, a good osmotic adjustment capacity and high RWC values all contributed to yield increases under terminal water‐stress conditions.     

不同刈割茬次与刈割时期对大麦饲草产量与品质的影响

大麦(Hordeum valgue L.)是一优质能量饲料作物,刈割是牧草管理的一种常规方式。为了研究刈割对大麦作为青（贮）饲的影响,以4份不同生态区具代表性的大麦新品种（系）为对象,分析了不同刈割茬次与刈割时期对大麦饲草产量与品质的影响。结果表明,所有品种第1茬饲草产量与品质均高于第2茬,重复刈割导致产草量不同程度下降,其中‘盐丰1号’降幅最小(13.0%),表现出较强的耐刈性。再次刈割,所有品种干鲜比、粗灰分含量增加,粗蛋白、粗脂肪含量下降,粗纤维、钙、磷含量变化因品种而异。分蘖期刈割大麦,营养物质含量高于灌浆期刈割,适口性好,可直接用作青饲料,且有利于植株再生。因此,2次刈割可于分蘖期开始,选用耐刈性好的大麦品种,分蘖期刈割大麦可直接用作青饲,灌浆期刈割可作为青贮饲料。     

Yield Responsiveness in Two- and Six-Rowed Barley Grown in Contrasting Nitrogen Environments

Two‐ and six‐rowed barley with different intrinsic ability to produce tillers and kernels per ear, would differ in responsiveness to nitrogen availability with environmental improvements. Two field experiments were carried out to elucidate how nitrogen supply (N₄₀ and N₁₅₀) affects yield and its components in two‐ and six‐rowed barley. High nitrogen increased aboveground dry matter at anthesis, by improving cumulative solar radiation intercepted by the crop, determining an increased dry‐matter production at maturity without changes in harvest index. In both barley types, variations in grain yield were explained by changes in kernels per unit land area rather than by differences in the average kernel weight. However, changes in the number of kernels were due to variations in the number of ears per m² in two‐rowed barley and the number of kernels per ear in six‐rowed barley. Ears per unit area showed a greater responsiveness in two‐ than in six‐rowed barley due to a higher nitrogen supply treatment, associated with their intrinsic higher tillering capacity, while the number of kernels per ear was more responsive in six‐ than in two‐rowed types. The fact that responses to nitrogen by the number of kernels per unit land area in two‐ and six‐rowed barley is better explained by different yield sub‐components, allows the speculation that the critical period for yield determination would differ between barley types.     

氮素养分对青稞营养功能特征及籽粒产量的影响

为确定在不同氮素条件下影响青稞生产力的关键性营养功能特征,以‘藏青2000’为试材,就不同施氮水平对青稞营养功能特征及籽粒产量的影响进行试验研究。结果表明：施氮显著提高了青稞籽粒产量、株高、相对生长率和比叶面积,而降低了单位叶面积根量和叶干物质含量,施氮水平与株高、相对生长率和比叶面积呈正相关关系,与单位叶面积根量和叶干物质含量呈负相关关系。随着施氮强度加大,产量持续提高,但增长速率下降,青稞籽粒产量与施氮水平呈二次曲线关系(y=-171.25x ²+1327.3x+10, R ²=0.958, P小于0.05)。青稞籽粒产量与株高(y=43.026x-2596.6, R ²=0.8994, P小于0.05)、相对生长率(y=7178.7x-150.66, R ²=0.5361, P小于0.05)和比叶面积(y=6.4604x+413.3, R ²=0.4153, P小于0.05)呈显著线性正相关,与叶干物质含量(y=-29.668x+4045.7, R ²=0.4488, P小于0.05)呈线性负相关关系,与单位叶面积根量(y=-2025.4x+2746.4, R ²=0.0579, P大于0.05)无明显相关性。结果表明：青稞的植株高度、相对生长率和比叶面积促进产量增长,叶干物质含量对产量有抑制作用,而单位叶面积根量对产量影响不明显。在本试验条件下,植株高度、相对生长率、比叶面积和叶干物质含量4个功能特征可在物种水平上被认为是影响青稞生产力的标记性特征。     

Effect of Sowing Technique on Growth of Undersown Crop and Yield of Spring Barley

Undersowing a main crop enables establishment of a catch crop in areas characterized by a short post-harvest period before the onset of winter. Techniques with lower costs than conventional undersowing by separate drilling are often regarded as unreliable. Undersowing by drilling after sowing spring barley ( Hordeum vulgare L.) was compared with broadcast sowing simultaneously with drilling barley. Various implements were coupled behind the combined drill in cases where seed was broadcast: a press-wheel attachment, a long-tined harrow and a cage roller. A fourth treatment did not include an implement coupled behind the drill. The undersown crop was sown as a seed mixture of 3 kg ha^–1 red clover ( Trifolium pratense L.) and 6 kg ha^–1 meadow fescue ( Festuca pratensis Hudson). The numbers of plants and weeds and the plant height were measured five times during the growing season. Above-ground biomass of the undersown species was determined at barley harvest and in late autumn. Grain yield of spring barley was recorded. Drilling resulted in the highest yield of undersown crop when an early summer drought occurred, but broadcasting in combination with use of seed covering equipment led to the least variation in biomass production over the 4 years the experiment was conducted. The relative proportion of meadow fescue in the crop was low in three years, and lower when broadcast than when drilled. Barley grain yield was highest when the seed was broadcast and seed covering equipment was used. Use of a cage roller increased weed biomass, but press-wheels and a long-tined harrow did not. Separate rolling after undersowing increased undersown crop yield in one year, but decreased grain yield in some cases.     

采收期对澳洲青苹苹果采后品质及虎皮病的影响

研究了在常温（20±1）℃和冷藏（0±0.5）℃条件下澳洲青苹苹果不同采收期对果实采后品质、生理和虎皮病发病率的影响。结果表明,晚采果实的品质和风味相对较好。常温贮藏条件下,晚采果实的乙烯跃变出现时间较早,但采收期对乙烯峰值的大小影响不大,直至果实严重腐烂也未发生虎皮病;冷藏条件下,延迟采收期能明显抑制和延缓澳洲青苹苹果虎皮病的发生,保持果实较高的可溶性固形物含量;贮藏后期早采果实的腐烂率急剧升高是由极其严重的虎皮病造成的。但果实采收越晚,耐贮性越差,腐烂率高而且腐烂出现的时间早,不宜长期贮藏。因此,综合上述因素,建议辽西地区澳洲青苹苹果贮藏果实应于生长发育后期（163～170 d）的10月中下旬采收,常温20℃条件下贮藏30～40 d,冷藏0℃条件下贮藏180 d内,虎皮病发病率低,可保持良好的品质与风味。     

野生大麦的抗旱性及其在大麦遗传改良中的应用

干旱是主要的非生物胁迫性灾害,极大地威胁到全球的粮食供应,是影响农业生产的最重要因素之一。因此,培育抗旱性植物是解决干旱危害和粮食危机的根本途径。野生大麦已经适应广泛的干旱环境并具有丰富的遗传多样性,它们的抗旱基因与抗旱相关数量性状位点(QTLs)已经确定,对改良大麦抗旱性有巨大的潜力。综述了野生大麦的抗旱性及其在大麦改良中的应用,并对大麦抗旱育种中存在的问题以及今后发展方向进行了展望。     

牛粪生物质炭基肥对青稞生长、产量及氮素利用的影响

为探讨不同配比的生物质炭基肥料对青稞生长、产量和氮素利用的影响。以牛粪为研究对象,在限氧条件下经高温热解炭化制成生物炭,将生物质炭与一定比例的化学肥料混合,制成生物质炭基肥料。研究表明,随着碳化的进行,牛粪中的全氮和有机质（有机碳）含量降低,材料的碳氮比也随之降低,而全磷、全钾的含量升高;增施牛粪生物炭,青稞叶片中叶绿素含量升高,促进作物对肥料中养分的利用,进而利于青稞生长,草木灰与化肥配施的叶片叶绿素含量最高;不同处理籽粒产量之间的差异达到极显著;化肥施入量减少至70%,牛粪生物炭施入量30%时,籽粒产量最高,达到4830.75 kg/hm²,高于有机肥、草木灰与化肥配施和羊粪的处理（较对照增产13.88%）;22500 kg/hm²羊粪处理的秸秆产量最高;同等氮输入条件下,减少化肥施用量,增加生物炭,可以提高氮素利用效率。