不同药剂防治玉米草地贪夜蛾试验

以6%阿维·氯苯酰SC(悬浮剂)为对照、清水为空白对照,研究了10%甲维·茚虫威SC、3%甲维盐WG(水分散粒剂)、15%多杀·茚虫威SC、30%氟铃·茚虫威SC、20%四唑虫酰胺SC 5种药剂防治玉米草地贪夜蛾的效果。试验结果表明,6种药剂对玉米草地贪夜蛾均有防治效果,药后3 d,以10%甲维·茚虫威SC、3%甲维盐WG、15%多杀·茚虫威SC防治效果最好,防治效果分别为82.94%、72.31%、65.08%;药后7 d,3%甲维盐WG、10%甲维·茚虫威SC、30%氟铃脲·茚虫威SC、15%多杀·茚虫威SC防治效果分别为91.49%、88.03%、70.25%、66.01%;药后14 d,除本地常用农药6%阿维·氯苯酰SC之外,其他几种农药保叶效果都在70%以上。综上,6种农药均可用于防治玉米草地贪夜蛾,建议轮换使用。     

正红505玉米花丝多糖结构及其降血糖活性分析

采用水提醇沉法提取正红505玉米花丝中的多糖成分,通过核磁共振波谱法(NMR)、高效液相色谱法(HPLC)、傅里叶变换红外吸收光谱法(FTIR)及气相色谱-质谱联用法(GC-MS)研究该多糖的单糖组成及结构,借助噻唑蓝比色(MTT)细胞试验,研究多糖CSP505对大鼠胰岛细胞RINm5F和人体肝脏细胞HepG2的降血糖活性。结果表明,多糖CSP505可能是一种由D-葡萄糖和D-半乳糖组成的β构型的多糖,其中葡萄糖和半乳糖的比约为3∶1。随着多糖浓度的增加,RINm5F细胞存活力随着增强,加药组中多糖以200、500、1000μg/mL浓度与四氧嘧啶共同作用时,细胞存活率分别提高了16.1%、16.1%、21.1%,达到极显著差异(P0.01);HepG2细胞存活能力也增强,加药组中多糖分别以200、500、1 000μg/mL浓度作用于细胞时,细胞存活力分别为100.4%、101.4%、103.3%。与阴性对照组相比较,加药组中在3个浓度的多糖作用下,腺苷酸环化酶(ADCY4)、糖原磷酸化酶(GPBB)和糖原合酶(GYS2)浓度表现出显著或极显著差异,而cAMP在浓度为1 000μg/mL时也表现出极显著差异。结果表明,该多糖可通过促进ADCY4与cAMP的合成来使胰岛素分泌增加,且可通过抑制糖原分解并促进糖原合成等过程起到降低血糖的作用。     

金刚砂辅助农杆菌进行玉米基因转化研究

对超声波处理方式进行改进,在超声波处理时,加入金刚砂以辅助EPSPS基因转导到玉米幼胚中。结果表明,800粒处理种子播种出苗93株,玉米苗经大田glyphosate筛选有27株具有抗性,进行PCR电泳检测,显示23株阳性,初步证明EPSPS基因已经转化到玉米植株中,转化率为29%。金刚砂辅助处理玉米基因转化具有可行性,利于生产实际操作。     

2019年美国玉米高产竞赛简报

介绍2019年美国玉米高产竞赛情况和竞赛结果，分析全美优胜者的分布区域、选用种子品牌及信息，进而分析玉米高产原因，从而提出美国玉米高产竞赛对我国玉米生产的启示和建议。     

Changes in phosphorus fractions in three tropical soils amended with corn cob and rice husk biochars

ABSTRACT

The formation of phosphorus (P) compounds including iron-P, aluminum-P and calcium-P in highly weathered tropical soils can be altered upon biochar addition. We investigated the effect of corn cob biochar (CC) and rice husk biochar (RH) pyrolyzed at three temperatures (300°C, 450°C and 650°C) on phosphorus (P) fractions of three contrasting soils. A 90d incubation study was conducted by mixing biochar with soil at a rate of 1% w/w and at 70% field capacity. Sequential P fraction was performed on biochar, soil and soil-biochar mixtures. Increase in most labile P (resin-P_i, NaHCO₃-P_i) and organic P fraction (NaHCO₃-P_o + NaOH-P_o) in CC and RH biochars were inversely related to increasing temperature. HCl-P_i and residual P increased with increasing temperature. Interaction of CC and RH with soils resulted in an increase in most labile P as well as moderately labile P (NaOH-P_i) fractions in the soils. CC increased most labile P in the soils more than RH. The increase in most labile P fraction in soils was more significant at relatively lower temperatures (300°C and 450°C) than 650°C. However, the increase in HCl-P_i and residual P of the soils was more predominant at high temperature (650°C). The study suggested that biochar pyrolyzed at 300–450°C could be used to increase P bioavailability in tropical soils.     

Preparation of Extruded Snacks with Flavored Flour Obtained from the Carcasses of Nile Tilapia: Physicochemical,Sensory, and Microbiological Analysis

This study aimed to develop extruded snacks including flour obtained from Nile tilápia carcasses, and then evaluate the chemical composition, colorimetry, thiobarbituric acid reactive substances, and microbiology. There was a significant increase in the levels of crude protein, ether extract, ash, and minerals, as well as a reduction in carbohydrates as more flour was included in the snacks. Increased levels of flavored flour caused reduction in the brightness of snacks. Oxidative rancidity was not detected in snacks. The inclusion of flour improved the nutritional value of extruded snacks without changing sensory characteristics. Microbiologically, the snacks are suitable for human consumption.     

Determining corn nitrogen rates using multiple prediction models

Weather uncertainty and soil spatial variability impact nitrogen (N) cycling and corn (Zea mays L.) growth, making accurate N predictions a challenge. Field studies were conducted in Lansing, Michigan, to evaluate a computer model (i.e., Adapt-N), a preseason year-based model (i.e., maximum return to N [MRTN]), and a crop sensor model (i.e., active canopy sensor with algorithm) for recommending corn N rates. To determine site-specific economic optimum N rates (EONR), five N rates were also applied (0, 33%, 66%, 133%, and 166% of the suggested MRTN) as starter + sidedress (SD) at V4. In a wet year (i.e., 2015), Adapt-N increased V8 SD N rates 35 kg N ha^?1 relative to the MRTN V4 SD N application. Although the greater rate of N may have provided additional yield protection, no statistical yield differences were observed between the two models. The MRTN model increased partial factor productivity (PFP) 20% relative to Adapt-N. Limited expression of V8 corn N deficiency reduced crop sensor total N rates (21–56 kg N ha^?1) and yield (0.82–1.05 Mg ha^?1) relative to other models. In a drier year (i.e., 2016), N demand was reduced (EONR 64 kg N ha^?1 less than 2015), resulting in similar corn response to all three models. Despite differences in actual corn N rate recommendations, all three models resulted in similar economic net returns across study years.

Abbreviations: EONR, economic optimum nitrogen rate; MRTN, Maximum Return to Nitrogen; NUE, nitrogen-use efficiency; PFP, partial factor productivity; SBNRC, sensor-based nitrogen rate calculator; SD, side-dress     

不同菌剂处理对玉米芯发酵过程中纤维素降解及相关酶活性的影响

以玉米芯为发酵原料,EM酵素菌、有机物料腐熟剂、金宝贝菌剂3种市售菌剂为发酵菌剂,研究了3种菌剂处理对玉米芯发酵过程中纤维素降解及相关酶活性的影响。结果表明,不同发酵菌剂处理后,纤维素降解酶的活性均增强,玉米芯基质中的纤维素、半纤维素降解率高于对照,其中EM酵素菌处理效果最佳;3种菌剂处理使木质素过氧化物酶活性增强,可有效提高玉米芯基质中的木质素降解率,其中金宝贝菌剂处理效果最佳,与对照相比降解率提高21.1%~50.5%。     

穗期玉米昼夜生理状态规律的遥感综合探测研究

针对QY、PRI、NDVI、水势分别从不同的方面反映玉米的生理状况,以甜糯二号玉米作为材料,通过田间试验测量玉米昼夜4个参数值,研究了QY、PRI、NDVI、水势4个参数的昼夜变化,并且分析它们之间的相关性。结果表明,QY、水势、PRI三者具有很强的相关性,并且能建立回归模型表示它们之间的联系。     

Feasibility analysis of NIR for detecting sweet corn seeds vigor

This paper explores the feasibility of particle-based detection and grading of seed vigor based on a self-built seed single-granulation device using near infrared spectroscopy (NIRS). Sweet corn with uniform kernel size was used for this study. The seed samples were divided into three types, they were normal seeds, artificially aged seeds and heat-damaged seeds. A 2-part spectral acquisition of each seed were performed, one for the collection of seeds that fall into the detection zone within the separation pipe, another was on the static platform, whose collection was performed on 5 faces of each seed. Partial least squares discriminant analysis (PLS-DA) was used to classify the original data of the seeds. In the 2 parts, the discriminant results of the unprocessed normal seeds and the artificial accelerated aging seeds, the untreated normal seeds and the heat-damaged seeds showed that classification accuracy was higher than 98%. The research indicates that the spectral data of different positions of seeds can reflect their activity information, and it is feasible to detect and classify seeds in real time in the detection area of the separation pipeline.