不同酶制剂对水稻秸秆和白酒糟混合青贮品质的影响

为研究不同酶制剂对水稻（Oryza sativa L.）秸秆和白酒糟（m︰m=1︰1）混合青贮品质的影响，设置CK（对照）、CEL（250 U·g^-1纤维素酶）和XYL（250 U·g^-1木聚糖酶）3个处理，青贮120 d后取样测定其青贮品质。结果表明：CEL处理的感官评定等级为良好；CEL和XYL处理的干物质、粗脂肪、钾和镁含量均显著高于CK（P<0.05），且CEL处理的粗蛋白和磷含量显著高于CK（P<0.05）；CEL和XYL处理的中性洗涤纤维、酸性洗涤纤维、木质素和纤维素含量均显著低于CK（P<0.05），且CEL处理显著低于XYL处理（P<0.05）；CEL和XYL处理30 h的养分消化率显著高于CK（P<0.05），且CEL处理48 h的养分消化率均显著高于CK（P<0.05）；CEL和XYL处理的饲用价值显著高于CK（P<0.05），且CEL处理显著高于XYL处理（P<0.05）。综上所述，添加纤维素酶、木聚糖酶能够提高水稻秸秆和白酒糟混合青贮的营养品质、养分消化率和饲用价值，且纤维素酶的添加效果优于木聚糖酶。     

小麦秸秆压缩弯曲特性试验研究

为给秸秆圆捆打捆装置和其它打捆机构提供相应的力学参数和理论基础,根据麦茎秆的几何尺寸,并利用万能试验机控制夹具加载速度对不同含水率的麦秸秆进行弯曲、轴向压缩和径向压缩等力学特性试验,得出载荷-位移等曲线,并获得相关力学参数数据。利用Origin将数据直观地反映出来,再用MatLab对试验数据进行拟合,得出拟合方程。试验结果表明:麦秸秆压缩所需要的力大于弯曲所需的力;含水率和夹具加载速度在一定范围内时,无论是在麦秸秆的弯曲试验还是压缩试验中,载荷峰值的大小与加载速度和含水率都有关,因此在设计打捆压缩成型机构时需考虑含水率与其关键机构工作转速对打捆装置的影响。     

Effects of AG1 and AG2 QTLs on Nonstructural Carbohydrate and Seed Management Options for Rice Seedling Growth and Establishment under Flooding Stress

Rice (Oryza sativa) plants acquired excess photosynthates in the form of nonstructural carbohydrates (NSCs) in their stems and grain. Despite keen interest in rice NSC, the dynamics of NSC accumulation, translocation and re-accumulation have not yet been well investigated. AG1 and AG2 QTLs associated with flooding tolerance through catalyzing starch into soluble sugar in germinating seeds. Here we conducted three experiments, greenhouse and field to lay the groundwork for large-scale diversity studies on grain NSC and some agronomic traits under direct-seeded rice (DSR) system, using elite lines incorporating AG1, AG2 and AG1-AG2 QTLs into the popular varieties PSB Rc82 and Ciherang-Sub1 along with the donors Kho Hlan On (AG1) and Ma-Zhan Red (AG2). In germinating seedlings, soluble sugars increased, while starch concentration decreased gradually especially in the tolerant checks and AG1-AG2 introgression lines under flooded soil. Soluble sugar accumulation in stem started to increase from the vegetative stage and peaked at the panicle initiation stage then gradually decreased towards the maturity stage. But Sub1-AG lines had higher sugar and starch concentrations at different growth stages than other genotypes in wet season 2016 and dry season 2017. Plant survival rate was positively correlated with the stem NSC at the early vegetative stage (21 days after sowing), and stem NSC was positively associated with plant height at different growth stages. Among the tested seeding rate, the most suitable seeding rate, 4 g/m² with shallow burial depth (0.5 cm), resulted in better seedling establishment, relatively higher seedling vigor index and higher leaf area index under flooding in DSR system. Introgression of AG1-AG2 QTLs had no any negative impact on nonstructural carbohydrate, germination rate, and growth and biomass production.     

不同水平的青贮饲料对饲喂稻草秸秆奶牛瘤胃微生物数量和微生物蛋白合成的影响

本试验的目的是确定饲粮中青贮银合欢添加水平对奶牛瘤胃微生物种群、氮平衡和微生物蛋白合成的影响。试验采用4×4拉丁方设计,选择12头初始体重为163±16 kg、带有瘤胃瘘管的奶牛,随机分为4个组,每组3个重复,每个重复1头牛。基础日粮以100%的水稻秸秆为原料,处理组分别用30%、60%和100%的青贮银合欢替代水稻秸秆,奶牛自由采食水稻秸秆和青贮银合欢,每天按照体重的0.2%补充浓缩料。结果表明,用60%青贮银合欢替代水稻秸秆组奶牛瘤胃微生物群,尤其是纤维素分解菌、蛋白分解菌和厌氧真菌的数量显著增加(P<0.05),各组对淀粉分解菌群无显著影响(P>0.05)。原生动物种群数量随日粮青贮银合欢添加水平的增加呈线性下降(P<0.05)(P<0.05)。此外,氮平衡和微生物蛋白合成均随着日粮青贮银合欢添加水平的升高而升高(P<0.05),其中以60%青贮银合欢组最高。结论:在本试验基础上,用60%青贮银合欢替代水稻秸秆可以显著提高奶牛体内的微生物数量和微生物蛋白的合成。     

双唑草腈对双季水稻田杂草的防效及后茬作物的影响

通过大田试验测定了双唑草腈及其与苄嘧磺隆、五氟磺草胺和扑草净混用对双季水稻田杂草的防效,并评价了双唑草腈对水稻及后茬作物的安全性。结果表明:2%双唑草腈GR对双季水稻田杂草具有良好的防治效果,210、315和420 g/hm~2处理药后30、45 d对禾本科杂草和阔叶类杂草的防效均在87%以上,低剂量140 g/hm~2处理药后30、45 d对双季水稻田禾本科杂草和阔叶类杂草防效均在75%以上。2%双唑草腈GR 140、210、315和420 g/hm~2处理对后茬作物小白菜、马铃薯、小麦、紫云英和冬季油菜生长安全。2%双唑草腈GR以140、210 g/hm~2分别与苄嘧磺隆或五氟磺草胺混用,药后30、45 d对禾本科杂草和阔叶杂草的防效均在93%以上,显著优于2%双唑草腈GR相应浓度的单剂处理,其中2%双唑草腈GR 210 g/hm~2+10%苄嘧磺隆WP 30 g/hm~2混用可以达到2%双唑草腈GR 315 g/hm~2处理的防治效果,且对水稻生长安全;单独施用50%扑草净WP 450 g/hm~2对双季稻田禾本科杂草的防效较差,其与2%双唑草腈GR混用后防效显著提高,但对水稻生长有较强的抑制作用。综上,双唑草腈及其与苄嘧磺隆、五氟磺草胺混用对双季水稻安全,可在双季水稻田推广应用。     

Weed seedling emergence in contrasting fodder crop systems following 30 years of cultivation in the lowlands of Northern Italy

Five fodder crop systems of different intensity (ranging from a double annual crop of Italian ryegrass + silage maize to a permanent meadow) were adopted for 30 years in the lowlands of Northern Italy under two input levels, differing mainly in their provision of organic fertiliser (manure). Herbicides were used in the maize crops included in all systems, except the meadow. After 30 years, the weed seedbank of all systems and input levels were assessed by the seedling emergence technique on soil samples from each plot. The cropping systems determined the abundance and composition of the weed assembly. Relatively few, frequent species made up the majority of the emerged seedlings in all systems, and there was no relationship between the total number of emerged seedlings and the mean number of species recorded in the different systems. Arabidopsis thaliana and Oxalis corniculata were abundant in the annual double crop and in the 3- and 6-year rotations that also comprised the annual double crop. These weeds, however, were unlikely to represent a major threat to the crops, due to their vigour and growth period. The permanent meadow tended to greater weed biodiversity than the other systems. The application of manure favoured the seedbank of species such as Lolium multiflorum, Digitaria sanguinalis and A. thaliana. Weed communities in the different systems were mainly determined by herbicide application, (through the ability of weeds to avoid its effects, determined by the weed life history and emergence period) and manure application (with its possible dual effect of spreading weed seeds and favouring nitrogen-responsive weeds).     

ET_0变化趋势分析及估算模型研究——以新乡站为例

【目的】参考作物蒸散量(ET_0)的估算是计算作物腾发量的基础,也是区域水资源评价与灌溉政策制定的前提,因此,研究ET_0变化趋势与估算模型能够对该地区农田灌溉用水预报提供基础支持,进而为灌溉制度的制定以及水资源高效利用提供科学依据。【方法】以河南新乡气象站1962―2016年气象资料为基础,运用Penman-Monteith模型计算ET_0序列,Mann-Kendall趋势检验法对年及季节尺度ET_0序列变化趋势进行分析,并用均值生成函数模型对其进行了拟合与验证。【结果】①新乡地区年尺度ET_0序列在1975―2016年间呈减小趋势,并在1985―2004年、2006年显著;②新乡地区春季ET_0序列在1982―1983年及1988―2003年间呈显著的减小趋势,夏季ET_0序列在1980―2012年间呈显著的减小趋势。③均值生成函数模型在对年尺度ET_0序列进行拟合时,其一致性系数达到0.83,绝对误差与相对误差分别在-120.8～120.0 mm及-14.0%～18.2%之间。④均值生成函数模型在对季节尺度ET_0序列进行拟合时,其一致性系数在春、夏、秋、冬各季节分别达到0.85、0.81、0.88及0.89,绝对误差分别在-60.2～64.3、-64.4～58.9、-39.6～32.8、-37.0～25.1 mm之间,相对误差分别在-20.1%～36.7%、-22.1%～32.1%、-18.0%～22.9%、-23.9%～24.6%之间。【结论】新乡地区年尺度ET_0序列在1985―2004年间显著减小,均值生成函数模型在对年及各季节尺度ET_0序列进行拟合时整体效果较好,因此,可通过其进行年及季节尺度ET_0序列的估算,且其在秋、冬二季的拟合效果明显好于春、夏二季。     

麦/油-稻轮作下秸秆还田与氮肥管理对直播杂交稻氮素利用特征的影响

【目的】探明秸秆还田和氮肥管理对麦/油后直播杂交稻氮素积累、转运、氮肥利用效率及籽粒产量的影响。【方法】选用优质三系杂交稻宜香优2115,采用二因素裂区设计,麦、油茬田同步开展试验,处理完全一致。主区为麦/油秸秆全量翻埋还田(M₁)和秸秆不还田(对照,M₀),副区设4个氮肥管理,即不施氮对照(N₀)、m_基肥∶m_分蘖肥∶m_促花肥∶m_保花肥比例分别为1∶0∶0∶0(N₁)、3∶3∶2∶2(N₂)、2∶2∶3∶3(N₃),测定了直播杂交稻主要生育时期各器官的氮素积累量及籽粒产量。【结果】结果表明,两种轮作方式下,氮肥管理对直播杂交稻主要生育时期的氮素积累、齐穗后茎鞘、叶片的氮素转运及稻株氮素利用效率均存在显著或极显著的调控效应。秸秆还田显著提高麦/油茬杂交稻中后期的氮素积累量、茎鞘和叶片的氮素转运量以及氮肥利用效率,其中,氮肥农学利用率、氮肥偏生产力和氮肥表观利用率较秸秆不还田分别提高了34.96%/28.76%、2.52%/2.61%和31.91%/22.30%。同时,油菜秸秆还田下直播杂交稻各生育时期氮素积累和产量较麦秆还田表现更好,籽粒产量提高481 kg/hm²(5.22%)。M₁N₂处理、M₀N₃处理下,直播杂交稻各阶段的氮素积累速率明显加大,促进结实期茎鞘和叶片的氮素向穗部转运,成熟期稻株氮素积累量优势明显且有较高的氮素利用效率(麦/油茬稻氮肥农学利用率、偏生产力和表观利用率分别达17.87 kg∙kg^-1/17.85 kg∙kg^-1、67.27 kg∙kg^-1/71.28 kg∙kg^-1、74.93%/75.05%),最终实现高产。【结论】在麦/油-稻轮作下秸秆全量还田,配合N₂氮肥管理,可有效提高直播杂交稻氮素吸收、利用效率,增加籽粒产量,尤以油菜秸杆还田的效果更好。     

芸薹素内酯对稻草基质育秧水稻秧苗生理特性及栽后生长的影响

【目的】筛选出机插水稻基质育秧芸薹素内酯(BR)适宜的施用方法及最佳用量。【方法】以中早39为供试材料,采用稻草基质旱育秧方式,探究BR不同处理方式和浓度对机插早稻秧苗生理特性及栽后生长的影响。【结果】施用BR可以提高秧苗的抗氧化保护酶活性,降低丙二醛含量,增加可溶性蛋白含量、总糖含量及C/N,秧苗根系活力提高了13.24%~48.31%,利于形成抗性强的健壮秧苗;喷施方式对提高秧苗超氧化物歧化酶、过氧化物酶、过氧化氢酶活性效果最佳,基施方式对降低秧苗丙二醛含量效果最好。施用适量BR也可促进秧苗机插后长出新叶、新根及返青,喷施方式效果最好;浸种、喷施方式还能增强秧苗机插后20~30 d的单株分蘖力。【结论】播种前和出苗后进行两次适量的BR处理,有利形成壮苗和栽后活棵返青及分蘖,以播前0.15 mg/L浸种和秧苗1叶1心期0.10 mg/L喷施效果为好。     

水稻因土质施肥方法探讨

土壤质地是土壤的基本物理性质之一,反应土壤中不同大小直径成土颗粒的组成状况。不同质地土壤间养分含量、蓄水导水、保肥供肥、保温导热、耕性、微生物种类及其活动等性能的差异,影响肥料的固定、转化、吸收和流失,并影响作物的产量形成,进而形成区域性的肥料利用效率的差异。水稻肥料利用状况的改善一直是研究热点,但土壤质地对肥料利用和水稻生长的影响研究相对较少。本文简要介绍了不同质地土壤的养分状况和理化性质差异,分析了土壤质地对作物生长发育的影响;并在简要评价测土配方施肥技术的基础上,初步探讨了不同土质土壤的肥料高效施用方法。