VA菌根真菌与根瘤菌和溶磷菌双接种对烟苗生长的影响

单接种及双接种均能很好地促进烟苗快速而健壮生长,且可使育苗时间缩短10～12天; 双接种效果优于单接种.根瘤菌对烟苗生长前期有良好效果,但对后期的作用却不大.在缺磷土壤上接种溶磷菌无效,在有磷源的条件下同时接种溶磷菌和G.M,能有效地达到节磷增产效果.     

花生种子大小和质量对生长和产量的影响

花生种仁的大小及重量对出苗速度及出苗率，幼苗的生长和发育，植株的花芽分化和成花率以及荚果产量等有很大的影响。大粒优质种仁可提高出苗速度２－５ｄ及出苗率３％－５％，植株生长健壮，花芽分化增多，成花率高，最终获得高产。     

不同收获时期对花生产量和品质的影响

以\"花育22号\"和\"花育20号\"为试验材料,设置8月1日、8月18日和9月4日3个收获期,分析不同收获期对花生产量和籽仁品质的影响。结果表明:延迟收获显著增加花生饱果率(P0.05),\"花育22号\"增幅较大。随收获期延长,两品种油酸和O/L值显著增加,精氨酸及\"花育22号\"蛋氨酸、苏氨酸、缬氨酸、天冬氨酸、5种人体半必需氨基酸总含量和总氨基酸含量显著降低(P0.05)。9月4日收获降低了两品种其他人体非必需氨基酸总量及\"花育20号\"赖氨酸、酪氨酸、丙氨酸、天冬氨酸和人体半必需氨基酸总含量,增加了两品种粗脂肪含量、\"花育22号\"甘氨酸和蛋白质及\"花育20号\"色氨酸含量(P0.05)。\"花育22号\"谷氨酸和亮氨酸及\"花育20号\"总氨基酸和蛋白质含量均呈先升后降的趋势。两品种脂肪含量、\"花育20号\"蛋白质含量均与积温和日照时数呈正相关,而\"花育22号\"蛋白质的含量与积温和日照时数呈负相关。从食用角度来看,\"花育22号\"宜早收获,而\"花育20号\"宜正常成熟,适当延后收获;从油用角度分析,两品种均应适当晚收。     

AM真菌和牛粪对铅污染土壤的修复效应

铅污染会对环境和人体健康产生较大风险,如何修复污染土壤、降低农产品中的铅残留值得深入研究。在温室盆栽条件下研究了接种丛枝菌根(AM)真菌、施加牛粪及复合处理对铅污染土壤的修复效应和机理。结果表明,在所有铅污染水平下,接种AM 真菌、施加牛粪和复合处理均显著促进烟草生长,改善烟草磷营养。复合处理在所有铅污染水平下均降低烟草铅残留量,而施加牛粪仅在轻度和中度铅污染水平下、接种AM 真菌仅在重度污染水平下作用显著。土壤pH 升高,铅有效性降低。可见,AM 真菌和有机肥对铅污染地区优质烟叶生产及铅污染土壤的植物修复具有一定的应用潜力。     

丛枝菌根真菌对不同氮效率烟草品种生长及养分吸收的影响

为明确丛枝菌根（AM）真菌对不同氮效率烟草品种养分吸收的作用,采用盆栽试验,以不接种处理（CK）为对照,研究了4株AM真菌（Fm、Ri、Ce、Gm）对不同氮效率品种烟草[ZY100（低）、K326（中）、NC89（高）]生长及矿质养分吸收的影响。结果表明,4种菌株均能与烟草根系形成共生关系。接种AM真菌,各处理烟株的干物质累积量、株高、最大根长、根表面积、根体积、总根长、根尖数及养分吸收量均得到不同程度提高。各烟草品种干物质累积量表现为NC89>ZY100>K326,菌根依赖性表现为ZY100>NC89>K326。各矿质养分中,接种AM真菌各处理N、P、K、Ca累积量增幅效果因菌株种类和烟草品种而异,微量元素Fe、Mn、Cu、Zn积累量增幅效果主要受菌株种类影响,Mg积累量在各处理间差异不显著。可见,接种AM真菌可以有效地促进烤烟根系形态的发育,优化根系结构,进而促进烟株对养分的吸收和积累。整体来看,氮效率低的ZY100更易与菌株建立共生关系,Ce菌株对3个氮效率品种烟草亲和力更强,综合而言以Ce-ZY100处理效果最佳。     

紫茎泽兰对花生生长的影响及其经济阈值

为有效反映大田条件下紫茎泽兰对花生生长和产量的直接危害和经济危害允许水平,采用添加系列试验和模型拟合的方法研究不同紫茎泽兰密度下花生的生长和产量变化以及花生田间透光率和紫茎泽兰水肥积累量的变化。结果表明,花生在紫茎泽兰的竞争干扰下,花生荚果数、百仁重和果仁产量均随紫茎泽兰密度的增加而逐渐降低。花生荚果数和百仁重的降低可能是花生减产的直接原因。此外紫茎泽兰对田间透光率和对水肥的累积量的影响也可能是花生减产的重要原因。幂函数模型能较好地拟合紫茎泽兰密度（x）与花生产量损失率（y）间的关系（y=1.712x1.063,P〈0.0001）。花生田采用人工除草、草甘膦和氨氯吡啶酸对紫茎泽兰进行防除时,紫茎泽兰的经济危害允许水平分别为6.06%、0.57%、0.77%,经济阈值分别为3.28、0.36、0.46株.m-2。     

不同种类有机肥与钼肥配施对连作花生生长发育及产量、品质的影响

采用大田试验,研究增施有机肥和钼肥对连作花生生长发育及产量和品质的影响。结果表明,在合理施用氮磷钾肥基础上,增施有机肥和钼肥可以明显促进花生的生长发育和根瘤的形成,提高产量,改善品质性状。增施钼肥花生单株根瘤数增加4．8～9．5个,侧枝长和单株有效分枝数分别增加1．4～10．3cm、1．2～2．5条,产量提高6．3％～22．3％,植株钼积累量提高1．72～2．69倍。增施有机肥花生产量提高8．2％～15．0％,蛋白质和粗脂肪分别增加13．2％～27．9％和10．3％～20．4％,但不同有机肥间效果差异不显著。本试验最佳组合为：每公顷施饼肥1200kg＋钼肥播种。     

Interactions between arbuscular mycorrhizal fungi and Trichoderma harzianum and their effects on Fusarium wilt in melon plants grown in seedling nurseries

BACKGROUND: Biological control through the use of Trichoderma spp. and arbuscular mycorrhizal fungi (AMF) could contribute to a reduction of the inputs of environmentally damaging agrochemical products. The objective of this study was to evaluate the interactions between four AMF (Glomus intraradices, Glomus mosseae, Glomus claroideum and Glomus constrictum) and Trichoderma harzianum for their effects on melon plant growth and biocontrol of Fusarium wilt in seedling nurseries. RESULTS: AMF colonisation decreased fresh plant weight, which was unaffected by the presence of T. harzianum. Dual inoculation resulted in a decrease in fresh weight compared with AMF‐inoculated plants, except for G. intraradices. AMF colonisation level varied with the AM endophyte and was increased by T. harzianum, except in G. mosseae‐inoculated plants. Negative effects of AMF on T. harzianum colony‐forming units were found, except with G. intraradices. AMF alone were less effective than T. harzianum in suppressing disease development. Combined inoculation resulted in a general synergistic effect on disease control. CONCLUSION: Selection of the appropriate AMF species and its combination with T. harzianum were significant both in the formation and effectiveness of AM symbiosis and the reduction of Fusarium wilt incidence in melon plants. The combination of G. intraradices and T. harzianum provided better results than any other tested. Copyright © 2009 Society of Chemical Industry     

栽培措施对南方水田花生产量及效益的影响

采用五因素二次通用旋转组合设计试验方法,研究了基本苗及氮、磷、钾、钙施用量五项主要栽培措施对南方水田春花生产量及效益的影响。通过产量及效益数学模型的优化与解析,以明确影响南方水田春花生产量及效益的关键因子和实现高产高效优化栽培的综合农艺措施。结果表明,在5个因素中,对花生产量的影响为：基本苗〉CaO〉P2O5〉K2O〉N;要获得300kg/667m^2以上产量和1500元/667m^2以上的经济效益,其最佳栽培措施组合是：保持基本苗1.75～1.83万/667m^2,施纯N：9.93～10.21kg/667m^2,P2O5：5.91～6.18kg/667m^2,K2O：11.80～12.07kg/667m^2,CaO：3.73～4.13kg/667m^2。     

几项栽培措施对香料烟生长及产质量的影响

通过田间试验,研究了揭膜中耕、栽植方式和烯效唑喷施等措施对香料烟生长和产、质量的影响。结果表明,揭膜中耕和烯效唑喷施可促进茎的横向生长,降低株高,减小叶面积;栽植方式对香料烟生物学性状影响不大。这些措施可增加烟株干物质量、叶绿素含量、根系活力和根冠比;烟叶总糖含量降低,烟碱和钾含量提高,内在化学成分得到改善,糖碱比趋于协调。与对照相比,揭膜中耕后,烟叶产值提高16.9%,烯效唑喷施浓度以15 mg/kg效果最好,其产值提高7.6%。      

间作对油菜和紫云英生长及产量的影响

为使用地与养地相结合,在保持油菜不减产的同时,建立合理的油菜/紫云英间作技术体系。采用大田试验,研究了紫云英（Astragalus sinicus L.）与不同密度油菜（Brassica napus L.）间作对二者生长和产量的影响。结果表明：紫云英与密度为20万~40万株/hm2油菜按2∶1带型间作（即1m宽带内播种两行油菜,1行紫云英）,间作油菜各处理不同生育期氮磷钾和碳的养分累积量均有高于或接近于油菜单作（MR）的趋势,间作油菜株高、根长、根颈粗、单株鲜重和产量接近于或显著高于密度为30万株/hm2的单作油菜。在保持油菜产量不显著降低的同时,间作模式可以收获3 592~5 724kg/hm2的紫云英绿肥。紫云英与不同密度油菜间作均表现土地资源利用优势（LER〉1）。     

快大液肥对烤烟生长及产质量的影响

在常量施肥的基础上,苗期和大田期叶面喷施或穴施快大液肥,能改善烟叶生长状况,促使烟苗生长健壮,烟株根系发达,生长旺盛,开片良好,烟叶产量,均价,产值有不同程度的提高;烟叶钾含量增加,含氮化合物下降,刺激性减小,香气增加。     

Stimulating effect of sorbitol and xylitol on germination and growth of some xerophilic fungi

Sorbitol and xylitol are polyols often used in foods as naturally occurring sugar substitutes. They provide sweet taste and reduced calories in products of intermediate moisture. This type of food is susceptible to spoilage by xerophilic molds which affect shelf life of foods and produce significant losses. The aim of the present work was to study the effect of glycerol, sorbitol and xylitol on the germination and growth of four xerophilic fungi at different temperatures and water activity levels. Penicillium chrysogenum, Wallemia sebi, Eurotium chevalieri and Eurotium repens were cultivated on malt extract agar with the addition of the respective polyols and a_w adjusted to 0.85, 0.88, 0.90 and 0.93. Incubation was made at 25, 30 and 35 °C. Results of the present study demonstrated that sorbitol and xylitol affect the growth kinetics of the four fungal species. The observed tendency was that these solutes shortened the germination times and increased the growth rates. The effect of each solute depended on the fungal species and the a_w/temperature combinations. At lower a_w the influence was more evident on the germination times while the effect on growth rates was more pronounced at higher a_w levels.