白菜型冬油菜抗倒伏性评价及其与株型性状的相关分析

于2018—2019年以44份不同抗倒性的白菜型冬油品系(种)为试材,依据改良倒伏系数(ILC)法对其抗倒伏性进行聚类分析和评价,探讨白菜型冬油菜株型、茎秆力学特性、干物质积累量等对其倒伏性的影响。结果表明:依据ILC可将白菜型冬油菜参试材料聚为3类:Ⅰ类为强抗倒性材料,包含2个品系(种);Ⅱ类为中等抗倒性材料,包含15个品系(种);Ⅲ类材料抗倒性最弱,包含27个品系(种)。聚类结果与田间倒伏分级结果基本吻合,两者呈极显著正相关(r=0.452~(**)),表明利用ILC评价白菜型冬油菜的抗倒伏性具有可靠性。与Ⅱ类、Ⅲ类材料相比,抗倒性强的Ⅰ类材料株高显著变矮,重心高度显著降低,其平均株高和重心高度比倒伏Ⅲ类材料分别降低19.8 cm和17.8 cm。白菜型冬油菜茎秆抗折力在三类材料间均存在显著差异,抗倒伏Ⅰ类参试材料平均茎秆抗折力是Ⅲ类材料的2.59倍。白菜型冬油菜倒伏系数与株高(r=0.346~*)、地上部鲜质量(r=0.344~*)、重心高度(r=0.579~*)呈显著正相关,与茎秆抗折力(r=-0.518~*)呈显著负相关。与Ⅱ类、Ⅲ类材料相比,Ⅰ类参试材料根长增长38%～41%,根鲜质量增大71%～102%,分枝部位降低32%～44%,一次分枝数增加10%左右、单株角果数增加30%～38%、角果长度增长1%左右、每角粒数增加11%～14%,千粒重增加21%～23%。白菜型冬油菜参试材料抗倒伏性存在显著差异,植株高度、重心高度、地上部鲜质量、茎秆抗折力等是影响其抗倒伏性的关键因素,株高较小、重心高度较低、茎秆抗折力大的白菜型冬油菜品种更高产抗倒伏。     

甘蓝型冬油菜抗寒性评价及遗传多样性分析

针对不同品种甘蓝型冬油菜抗寒性和遗传多样性存在差异等特点,于2021年采用随机区组设计,结合系统聚类分析法及SSR标记对32份甘肃省生产应用甘蓝型冬油菜与9份陕西中部及江苏省现推广应用甘蓝型冬油菜品种的越冬率及春化特性差异和遗传多样性进行分析,探究其抗寒性差异,分析品种间遗传多样性及亲缘关系。结果表明：甘肃省生产应用甘蓝型冬油菜越冬率高于80%,陕西中部及江苏省甘蓝型冬油菜品种越冬率均小于25%,且抗寒性强弱差异明显;根据春化率高低,参试材料可分为强冬性、冬性、半冬性、弱冬性等4个级别;强冬性材料未现蕾的植株占比高,春播后难以抽薹现蕾进入生殖生长,加权平均薹高随之偏低,抗寒性强;春化率越高,成熟期的加权平均株高越高且抗性越弱,越冬率与春化率呈负相关关系;筛选出的98对多态性高的引物组合共扩增出976个总位点,其中多态性条带750个,多态位点比率达72%,说明其分子遗传水平上的多态性丰富度高,陕西中部及江苏省甘蓝型冬油菜遗传多样性整体高于甘肃省生产应用甘蓝型冬油菜;通过聚类分析,可将甘蓝型冬油菜划分为9类;根据群体遗传结构分析及主成分分析可分为3大类,与抗寒性分类趋于一致。研究成果有望为鉴别甘蓝型冬油菜品种、构建指纹图谱及选择不同生态区适宜品种等研究奠定基础。     

北方强冬性区白菜型冬油菜临界安全越冬率及产量补偿效应分析

以3个不同抗寒性的白菜型冬油菜品种为材料,在模拟不同越冬条件下,探讨越冬率对强抗寒性白菜型冬油菜产量、株型性状、角粒性状、生育期等的影响。结果表明:当越冬率在30%～100%范围内,随越冬率的增加,白菜型冬油菜产量呈先增加后降低的趋势,陇油7号、冬油2号越冬率为85%时产量分别为4 462.2 kg·hm~(-2)和4 057.0 kg·hm~(-2),达到最高值;天油4号越冬率为90%时产量最高,为3 591.8 kg·hm~(-2)。方差分析表明,陇油7号和天油4号越冬率大于75%,冬油2号越冬率大于70%时,越冬率变化对其产量水平无显著影响,而越冬率低于这一阈值时,其产量显著降低。回归分析表明,白菜型冬油菜越冬率与其产量的关系符合线性模型;相关性分析表明,白菜型冬油菜越冬率变化与植株分枝部位呈显著正相关(P0.05),与单株分枝数、角果长度和数量、粒数和粒重、单株重量等呈显著负相关(P0.05),种子、角果和侧枝的干鲜质量及蔗糖含量与越冬率变化呈显著或极显著负相关(P0.01或P0.05)。因此,冬前播种密度保持在65万株·hm~(-2)时,我国北方强冬性区白菜型冬油菜安全越冬临界值范围为70%～75%,不同品种的安全临界越冬率存在差异;在一定范围内,增加白菜型冬油菜的分枝和结实性能,对返青群体不足导致的产量损失具有补偿效应。     

PEG模拟水分胁迫下白菜型冬油菜芽期根系特征及抗旱性研究

本试验采用砂培法,以18%(w/V)聚乙二醇(PEG6000)模拟水分胁迫研究18份白菜型冬油菜芽期根系特征,并结合盆栽试验研究根系特征与抗旱性关系。结果显示,水分胁迫对白菜型冬油菜侧根数、根重、根冠比有显著的抑制作用,对根长影响相对较小。相关性分析结果显示:相对侧根数、相对根长与相对活力指数之间呈显著正相关,可以作为白菜型冬油菜抗旱评价的辅助指标。不同来源的材料在根系侧根数、根重、根冠比方面差异显著,可作为区别不同来源材料抗旱性强弱的指标。对材料抗旱性进行聚类分析,在距离10时18份材料可以分五个类群,其中A类抗旱性最强,平均相对侧根数72.90%、平均相对根长100.37%、平均相对根重79.60%、平均相对根冠比119.93、平均相对活力指数0.64。根据相对活力指数及聚类分析结果,筛选出抗旱性较强的3份白菜型冬油菜:宁油2号、陇油7号和平油1号。对比分析盆栽试验,幼苗期总生物量干重与根冠比、根系干重、地上部干重、主根长均呈极显著正相关;芽期PEG胁迫下根系特征分析结果显示:早期生长活力较好的材料在盆栽试验有较高的生长势。早期采用模拟干旱的方法可以筛选抗旱性较强的材料。     

灌浆天数对北方白菜型冬油菜产量和品质的影响

为了研究北方白菜型冬油菜在灌浆成熟过程中产量和品质性状的特征特性变化,以白菜型冬油菜陇油12号和09鉴8为材料,分析冬油菜在终花后10、20、30、40、45 d的植株、角果、籽粒形态和干鲜重,产量和品质性状的变化。结果表明,随着籽粒灌浆成熟,植株和角果颜色呈墨绿—青绿—黄绿—蜡黄—肤白色变化。角果中籽粒大小呈小—大—小变化,种子颜色呈绿色—褐绿相间—褐色—紫色—黑色变化。植株、角果、籽粒鲜重呈先增加后降低的单峰变化曲线,基本呈抛物线状,且分别在终花后20、30、40 d鲜重达到最大,而植株、角果、籽粒干重呈先增加后保持不变的变化趋势。同时千粒重、单株产量、经济系数也呈先增加后保持不变的S型增长曲线,且在终花后30 d达到最大,之后保持不变。相关分析表明,灌浆时间长短与籽粒鲜重、千粒重、经济系数呈极显著的正相关关系,相关系数分别为0.991、0.962、0.968(P0.01);与单株产量、含油率呈显著的正相关关系,相关系数分别为0.947、0.940(P0.05);与蛋白质呈显著的负相关关系,相关系数为-0.886(P0.05)。通过主成分分析方法打分,各处理的综合得分排名为40 d45 d30 d20 d10 d,因此,籽粒灌浆天数对白菜型冬油菜的产量和品质影响明显。综合评价得出,蜡黄期(约终花后40 d)产量和品质等性状达到最佳,是收获的最适宜时期。     

燕麦种质资源农艺性状的遗传多样性分析

分析了国内外54份燕麦种质资源的遗传多样性,归纳其遗传亲缘关系,为合理利用燕麦品种(系)资源提供理论依据。结果表明:(1)54份种质资源农艺性状间存在广泛的遗传多样性,5个质量性状(粒色、粒型、穗型、小穗型、抗病性)以抗病性的多样性指数最高,粒色的遗传多样性指数最低;8个数量性状(单株分蘖数、株高、穗长、小穗数、轮层数、单株粒数、单株粒重、千粒重)以单株粒重的遗传多样性指数最高,变异系数最大。(2)聚类分析将54份种质资源的8个数量性状分为4大类群,类群Ⅰ为高秆、大粒型育种目标亲本材料;类群Ⅱ为矮秆育种目标亲本材料,类群Ⅲ的有益性状不明显,为多目标性状育种的亲本材料,类群Ⅳ为增加轮层数、小穗数等育种目标的优良材料。     

北方白菜型冬油菜花器特性及农艺性状与含油量的相关性

为研究北方白菜型冬油菜花冠直径与千粒重及含油量之间的相关性,以20份不同的白菜型冬油菜为材料，测定花器大小、农艺性状、种子含油量及蛋白质含量,并对控制花器特征基因mf6、apetala和myb进行实时荧光定量PCR分析。结果表明:花冠直径受雌蕊直径影响较大,主成分分析提取的3个主成分可综合为花器各性状长度、雌蕊直径和花器各性状宽度；以花冠直径为指示性状，将20份白菜型冬油菜花冠划分为3类群；相关性分析表明，花冠直径与千粒重呈极显著正相关，相关系数0.663；千粒重与含油量呈极显著正相关，与蛋白质含量呈显著负相关。相较于小花，mf6在大花中相对表达量上调了151.63%，而apetala和myb分别下调了83.80%和72.70%。北方白菜型冬油菜品种间花器大小存在显著差异；在育种中可通过增加花冠直径来提高千粒重，进而增加油菜产油量，培育高含油量白菜型冬油菜品种。mf6、apetala和myb基因对白菜型冬油菜花器生长发育均具有一定调控作用。     

宁夏春小麦抗旱性的遗传多样性分析

以宁夏春小麦育成品种、地方品种以及引进种质等共91份春小麦为材料,在干旱胁迫(雨养)和正常灌溉两种水分处理下,调查了11个农艺性状及其耐旱指数,计算其遗传多样性指数并进行聚类分析。结果表明:不孕小穗数的变异系数最高,干旱胁迫与正常灌溉条件下分别为63.5%和51.5%,穗叶距次之,干旱胁迫和正常灌溉条件下分别为36.9%和36.3%;产量的耐旱指数与株高、穗下节长、穗叶距的耐旱指数呈极显著负相关;不同性状的多样性指数差异较大,变化范围从0.99到2.48,平均为1.73,其中,不实小穗数的多样性指数最高,为2.48。根据表型性状将参试材料分为5个类群,其中第IV类群材料表现为对水分条件不敏感,适于在干旱条件下种植。总体来看,宁夏春小麦种质的遗传基础较狭窄,育种家应广泛搜集利用国内外小麦种质及小麦近缘物种,以拓宽现有种质资源的遗传基础,为选育突破性小麦品种奠定基础。     

DNA去甲基化参与提高白菜型冬油菜抗寒性的生理机制

利用来自不同育种环境的10份白菜型冬油菜材料,通过半致死温度的测定分析其抗寒性与环境的关系,并利用不同浓度DNA甲基化抑制剂5-azaC处理,分析DNA去甲基化对白菜型冬油菜DNA整体甲基化水平及低温胁迫下苗期生理特性的影响。结果表明,不同育种环境选育的材料,其半致死温度具有显著差异,其中材料2018-FJT、DT-7、DT-9与MXW-1的半致死温度分别为-16.04℃、-15.98℃、-15.63℃、-15.04℃;材料CT-2360、CT-2380、CT-2400、CT-2420、CT-2440、CT-2460的半致死温度分别为-11.32℃、-11.6℃、-11.42℃、-11.44℃、-12.97℃、-13.28℃。依据半致死温度,10个白菜型冬油菜抗寒性由强到弱依次为:2018-FJTDT-7DT-9MXW-1CT-2460CT-2400CT-2380CT-2420CT-2440CT-2360。抗寒性的形成与育成环境的纬度和年平均气温呈极显著正相关。选择抗寒性及产地不同的4个材料CT-2360、MXW-1、2018-FJT、DT-7进行生理测定,结果表明,1 000μmol·L~(-1) 5-azaC处理能显著抑制幼苗的根生长,4个材料的根长较对照减少93.14%～95.06%;低温下5-azaC处理对抗寒性较弱材料CT-2360幼苗的相对电导率、丙二醛含量以及强抗寒性材料DT-7幼苗的脯氨酸、可溶性蛋白含量影响最显著(P0.05);低温处理过程中,4个材料的SOD、POD、CAT活性均上升,以低温处理5d最显著(P0.05),其中2018-FJT的SOD活性增幅最高,为45.85%,DT-7的POD活性增幅最大,为460%,CT-2360的CAT活性增幅最显著,为321.02%。HPLC分析发现常温下抗寒性较弱材料CT-2360的甲基化水平为77.48%,高于其他3个抗寒性强的材料;经过5-azaC处理后发生明显的去甲基化作用,证明抗寒能力受DNA去甲基化的调控。     

甘蓝型冬油菜在西北寒旱区适应性分析

为了研究甘蓝型冬油菜在西北寒旱区的适应性,以29份甘蓝型冬油菜品系为材料,分析在天水、兰州两个试点越冬率、生育期、产量、含油量及农艺性状的差异。结果表明,参试品系在天水试点越冬率均高于兰州试点,在天水试点,21份参试品系越冬率80.00%以上,而兰州试点在覆盖条件下越冬率平均为14.49%,最高为平甘1号(48.50%)。联合方差表明,试点气候差异是引起越冬率差异的最主要原因。与天水试点相比,参试品系北移至兰州试点后越冬期延长,冬后生育期缩短,全生育期延长;在天水试点参试品系株高、分枝部位、主花序长度、千粒重、折合每667 m~2产量、含油量平均值分别为133.52 cm、32.79 cm、51.37 cm、3.15 g、184.20 kg、40.16%,较兰州分别高22.11 cm、31.58 cm、2.47 cm、0.66 g、160.54 kg、22.54%;变异分析表明,在天水试点参试品系越冬率、主要农艺性状、产量、含油量变异系数相对兰州试点较小,相对稳定。结论:天水试点气候条件更适合甘蓝型冬油菜的生长,参试品系越冬率高、农艺性状良好、产量高、含油量高,适应性强。     

CO2浓度升高对取食不同寄主的西花蓟马和花蓟马生理酶活性的影响

为明确取食不同寄主植物的西花蓟马和花蓟马对CO_2浓度升高的响应机制,分别选取四季豆、茼蒿和辣椒寄主,分析不同CO_2浓度对2种蓟马成虫体内解毒酶和保护酶活性的影响。结果表明,2种蓟马的羧酸酯酶(Car E)、乙酰胆碱酯酶(Ach E)、微粒体多功能氧化酶(MFO)、过氧化氢酶(CAT)和过氧化物酶(POD)活性均随着CO_2浓度的升高而增强。与对照相比,高CO_2浓度下西花蓟马取食四季豆时Car E和POD活性分别升高了21.70%和40.16%,取食茼蒿时Car E、MFO和POD活性分别升高了40.11%、6.73%和43.85%,而以辣椒为寄主时超氧化物歧化酶(SOD)活性降低了57.56%;在800μL/L高CO_2浓度下,花蓟马的Car E、Ach E和MFO活性均略有升高;四季豆、茼蒿和辣椒饲养的花蓟马SOD活性分别下降了26.84%、52.16%和53.71%。研究表明,2种蓟马均能通过调节体内的生理酶活性来适应环境的变化,且西花蓟马的适应能力强于花蓟马。     

<Emphasis Type="Italic">In vitro</Emphasis> Selection of Maize Rhizobacteria to Study Potential Biological Control of <Emphasis Type="Italic">Aspergillus</Emphasis> Section <Emphasis Type="Italic">Flavi</Emphasis> and Aflatoxin Production

The aims of this study were to select bacterial isolates from the non-rhizophere of maize soil and to examine their antagonistic activity against Aspergillus section Flavi strains. The first selection was made through ecophysiological responses of bacterial isolates to water activity (a_w) and temperature stress. Subsequently, an Index of Dominance test (I_D), ecological similarity and inhibition of the lag phase prior to growth, growth rate and aflatoxin B₁ accumulation were used as criteria. From the first assay nine bacterial strains were selected. They grew well at 25 and 30 °C, with growth optima between 0.982 and 0.955 a_W using 48 h of incubation. There was ecological similarity between the bacterial strains Bacillus subtilis (RCB 3, RCB 6), Pseudomonas solanacearum RCB 5, Amphibacillus xylanus RCB 27 and aflatoxigenic Aspergillus section Flavi strains at 0.982 at 25 °C. The predominant interaction between all selected bacteria and fungi in dual culture was mutual intermingling at 0.982. Mutual inhibition on contact and mutual inhibition at a distance was observed at 0.955 a_w, between only four bacteria and some Aspergillus strains. Bacillus subtilis RCB 55 showed antifungal activity against Aspergillus section Flavi strains. Amphibacillus xylanus RCB 27, B.␣subtilis RCB 90 and Sporolactobacillus inulinus RCB 196 increased the lag phase prior to growth and decreased the growth rate of Aspergillus section Flavi strains. Bacillus subtilis strains (RCB 6, RCB 55, RCB 90) and P. solanacearum RCB 110 inhibited aflatoxin accumulation. Bacillus subtilis RCB 90 completely inhibited aflatoxin B₁ accumulation at 0.982 a_W. These results show that the bacterial strains selected have potential for controlling Aspergillus section Flavi over a wide range of relevant environmental conditions in the stored maize ecosystem.     

短时极端高温对亚洲玉米螟卵、初孵幼虫和成虫的影响

为探明短时极端高温对亚洲玉米螟Ostrinia furnacalis(Guenée)的影响,采用耐热能力测定方法,研究了亚洲玉米螟经6 h高温处理后的半数致死温度(LT50)、存活率以及不同高温下的半数致死时间(Lt50)。结果表明,经6 h高温处理后,亚洲玉米螟卵、初孵幼虫和成虫的LT50分别为40.24~40.44、38.59和42.84~44.54℃;当卵、初孵幼虫、1日龄和3日龄成虫分别在37、35、41和37℃时,其存活率与对照均无显著差异,而分别在39、37、43和39℃时,其存活率显著低于对照,卵、初孵幼虫、1日龄和3日龄成虫的短时高温阈值分别为37~39、35~37、41~43和37~39℃;当温度高于高温阈值时,卵、初孵幼虫和成虫的Lt50分别为0.38~6.31、0.22~8.35和3.80~24.15h,且雄成虫的Lt50小于雌成虫。研究表明,短时极端高温对亚洲玉米螟的存活率具有显著影响。     

Histochemical studies on the accumulation of reactive oxygen species (O2 and H2O2) in the incompatible and compatible interaction of wheat—Puccinia striiformis f. sp. tritici

The generation and accumulation of reactive oxygen species (ROS), superoxide anion (O₂⁻) and hydrogen peroxide (H₂O₂), were studied in the interaction between wheat cv. ‘Suwon 11’ and two races of Puccinia striiformis f. sp. tritici (avirulent and virulent). Generation of O₂⁻ and H₂O₂ was analyzed histochemically using nitroblue tetrazolium (NBT) and 3,3-diamino-benzidine (DAB), respectively. At the pre-penetration stage during appressorium formation both stripe rust races induced H₂O₂ accumulation in guard cells. In the incompatible interaction, a rapid increase of O₂⁻ and H₂O₂ generation at infection sites was detected. The percentage of infection sites showing NBT and DAB staining was 36.1% and 40.0%, respectively, 12 h after inoculation (hai). At extended incubation time until 24 hai, percentage of infection sites showing H₂O₂ accumulation further increased, whereas those exhibiting O₂⁻ accumulation declined. The early infection stage from 12 to 24 hai coincided with primary haustoria formation in mesophyll cells. In contrast, in the compatible interaction, O₂⁻ and H₂O₂ generation could not be detected in most of the infection sites. In the incompatible interaction, intensive DAB staining was also determined in mesophyll cells, especially in cell walls, surrounding the infected cells 16–24 hai; thereafter, these cells contained fluorescing compounds and underwent hypersensitive response (HR). The number of necrotic host cells surrounding the infection sites increased continuously from 20 to 96 hai. It might be concluded that H₂O₂ accumulation during the early infection stage is associated with the occurrence of hypersensitive cell death and that resistance response is leading to arrest the avirulent race of the obligate stripe rust pathogen. In the compatible interaction at 96 hai, H₂O₂ accumulation was observed in mesophyll cells surrounding the rust lesion.     

Pathogenicity and mycotoxin production by <Emphasis Type="Italic">Fusarium proliferatum</Emphasis> isolated from onion and garlic in Serbia

Fusarium proliferatum can occur on a wide range of economically important vegetable plants but its role in disease is not always well established. In 2000 and 2001, from forty-one field samples of wilting onion and garlic plants in Serbia, F. proliferatum as the predominant fungal species was isolated from root and bulbs. Seventy isolates were firstly characterized for their sexual fertility and were shown to be mostly members of Gibberella intermedia (sixty-seven of seventy isolates, the remaining three isolates were unfertile), the sexual stage of F. proliferatum (syn. mating population D of G. fujikuroi complex). A selected set of eleven F. proliferatum isolates from both hosts were also tested for their pathogenicity and toxigenicity. Although onion and garlic plants were susceptible to all isolates, onion plants showed a significantly higher disease severity index. Six of the eleven isolates of F. proliferatum produced fumonisin B₁ from 25 to 3000 μg g⁻¹, and beauvericin from 400 to 550 μg g⁻¹; ten isolates produced fusaric acid from 80 to 950 μg g⁻¹ and moniliformin from 50 to 520 μg g⁻¹. Finally, all isolates produced fusaproliferin up to 400 μg g⁻¹. These results confirm F. proliferatum as an important pathogen of garlic and onion in Europe and that there is a potential mycotoxin accumulation risk in contaminated plants of both garlic and onion.     

Bicarbonate solutions control powdery mildew (Leveillula taurica) on sweet red pepper and reduce the development of postharvest fruit rotting

Disease severity of powdery mildew (causal agentLeveillula taurica (Lév.) Arn.) on pepper (Capsicum annuum), defoliation and fruit sunscald rating were significantly reduced (P=0.05) by foliar applications of sodium or potassium bicarbonate solutions, compared with water or penconazole (Ophir). Preharvest application of bicarbonate solutions significantly reduced (P=0.05) postharvest decay development on sweet red pepper fruits.     

禾谷镰刀菌CYP51A基因对五种三唑类杀菌剂敏感性的影响

为进一步明确14α-脱甲基酶编码基因CYP51A在禾谷镰刀菌Fusarium graminearum对三唑类杀菌剂敏感性中的作用,利用Split-marker方法敲除禾谷镰刀菌CYP51A基因并获得敲除CYP51A基因的禾谷镰刀菌ΔFgCYP51A菌株,比较该菌株和野生型菌株PH-1对5种三唑类杀菌剂的敏感性变化。结果表明,ΔFgCYP51A菌株对丙环唑、戊唑醇、烯唑醇、三唑醇和三唑酮的EC₅₀分别为0.024、0.047、0.148、0.154和0.474 mg/L。ΔFgCYP51A菌株对戊唑醇、三唑醇、三唑酮和丙环唑的敏感性均显著增加,而对烯唑醇的敏感性无明显变化。表明FgCYP51A基因与禾谷镰刀菌对三唑类杀菌剂的敏感性有关。     

Calcium reducesBotrytis c1nerea damages to plants ofRuscus hypoglossum

Plants ofRuscus hypoglossum L. were grown in containers with perlite, an inert medium, or with soil, under similar-to-commercial conditions, for three winter seasons. Constant fertilization with soluble calcium [Ca(NO₃)₂] through the root zone resulted in a reduction of up to 78% in postharvest rot caused by artificial inoculation withBotrytis cinerea Pers. ex Fr. Control plants were treated by fertilization with N,P,K and all other elements, identical to the fertilizer containing calcium. Foliar application of Ca(NO₃)₂ to ruscus bushes or application of this compound or of CaCl₂ or CaSO₄ to mature cut branches standing in water, resulted also in a significant reduction in postharvest phylloclade rot. Application of CaSO₄ and Ca(H2PO₄)₂ + CaSO₄ to ruscus plants, from fertilizers containing 22% Ca and releasing the cation gradually, effectively reduced the susceptibility of cut branches to infection by_{B. cinerea.}     

Toxigenic Fusarium Species of Liseola Section in Pre-harvest Maize Ear Rot, and Associated Mycotoxins in Slovakia

The occurrence of Fusarium species of Liseola section and related toxins was investigated for two years (1996 and 1998) on maize ear rot samples collected in the most important areas for maize growing in Slovakia. The species most frequently isolated was F. verticillioides, followed by F. proliferatum in 1996 and F. subglutinans in 1998. Most of the strains belonged to mating populations A, D, and E of the teleomorph Gibberella fujikuroi. Fusarium graminearum was also frequently recovered in both the years of investigations. Toxin analysis of maize ears showed that most of the samples (21 out of 22) were contaminated with at least one toxin. In particular, the concentration of fumonisin B₁, and fumonisin ₂ was up to 26.9 and 5.1gg^-1, respectively in 1996, and up to 12.1 and 6.3gg^-1, respectively in 1998. Beauvericin was detected only in one sample in 1996. Seven samples in 1996 were contaminated by fusaproliferin up to 8.2gg^-1, but just traces of the toxin were found in one sample in 1998. All 29 strains of F. verticillioides, two of three strains of F. proliferatum and none of eight F. subglutinans strains isolated from samples produced fumonisin B₁ in culture on whole maize kernels (0.1–5646 and 940–1200ugg^-1, respectively). Two strains of F. subglutinans and two of F. proliferatum produced beauvericin (up to 65 and 70gg^-1, respectively). Ten strains of F. verticillioides produced beauvericin: 9 strains produced a low amount (up to 3gg^-1), while only one of them produced a high level of toxin (375gg^-1). Fusaproliferin was produced by two F. proliferatum strains (220 and 370gg^-1), by seven F. subglutinans (20–1335gg^-1) and by three F. verticillioides (10–35gg^-1). This is the first report on fusaproliferin production by F. verticillioides, although at low level.     

黄河上游重要水源补给区参考作物蒸散量变化特征分析

利用甘南牧区4个气象观测站1971-2010年的地面气象观测资料,运用Penman-Monteith公式计算得出牧区四站逐月ET0值.通过统计分析、相关分析、小波及Mann-Kendall法等方法对甘南牧区ET0的变化特征进行了分析,并就高原上气象因子与ET0的相关性做了进一步研究.结果发现甘南牧区各县ET0年际变化呈逐年上升趋势,上升趋势达8.8～ 19.5mm/10a;1985年以前有明显的准10 a周期,2000年到2010年间出现了准5 a周期;在90年代以后的20年中上升更快,并于1996年以后出现了突增.牧区ET0夏季最大,并且逐年上升最快;冬季最小,逐年上升最慢.牧区ET0的空间分布不均匀除了与当地高原特殊地形地貌复杂性有关外,还与影响参考作物蒸散量的主要气象因子的不同有关.