快灭灵40DF防除小麦田杂草的效果及其对小麦的安全性

快灭灵４０ＤＦ是美国ＦＭＣ公司研制的新型禾谷类作物田除草剂。在小麦４￣６叶期,喷施快灭灵４０ＤＦ２２．５ｇ／ｈｍ＾２对麦田新的优质阔叶草种具有较好的防效,对大巢菜和繁缕的防效为８０％￣８５％,但是对禾本科杂草无效;     

Early season weed mapping in sunflower using UAV technology: variability of herbicide treatment maps against weed thresholds

Site-specific weed management is defined as the application of customised control treatments only where weeds are located within the crop-field by using adequate herbicide according to weed emergence. The aim of the study was to generate georeferenced weed seedling infestation maps in two sunflower fields by analysing overlapping aerial images of the visible and near-infrared spectrum (using visible or multi-spectral cameras) collected by an unmanned aerial vehicle (UAV) flying at 30 and 60 m altitudes. The main tasks focused on the configuration and evaluation of the UAV and its sensors for image acquisition and ortho-mosaicking, as well as the development of an automatic and robust image analysis procedure for weed seedling mapping used to design a site-specific weed management program. The control strategy was based on seven weed thresholds with 2.5 steps of increasing ratio from 0 % (herbicide must be applied just when there is presence or absence of weed) to 15 % (herbicide applied when weed coverage >15 %). As a first step of the imagery analysis, sunflower rows were correctly matched to the ortho-mosaicked imagery, which allowed accurate image analysis using object-based image analysis [object-based-image-analysis (OBIA) methods]. The OBIA algorithm developed for weed seedling mapping with ortho-mosaicked imagery successfully classified the sunflower-rows with 100 % accuracy in both fields for all flight altitudes and camera types, indicating the computational and analytical robustness of OBIA. Regarding weed discrimination, high accuracies were observed using the multi-spectral camera at any flight altitude, with the highest (approximately 100 %) being those recorded for the 15 % weed threshold, although satisfactory results from 2.5 to 5 % thresholds were also observed, with accuracies higher than 85 % for both field 1 and field 2. The lowest accuracies (ranging from 50 to 60 %) were achieved with the visible camera at all flight altitudes and 0 % weed threshold. Herbicide savings were relevant in both fields, although they were higher in field 2 due to less weed infestation. These herbicide savings varied according to the different scenarios studied. For example, in field 2 and at 30 m flight altitude and using the multi-spectral camera, a range of 23–3 % of the field (i.e., 77 and 97 % of area) could be treated for 0–15 % weed thresholds. The OBIA procedure computed multiple data which permitted calculation of herbicide requirements for timely and site-specific post-emergence weed seedling management.     

麦茬高度对除草剂控制杂草效果的影响

麦茬的存在造成了免耕田控制杂草使用过量除草剂。农户小麦收割时由于使用不同的联合收割机服务形成了不同的麦茬高度,多数农民认为高麦茬环境下杂草控制是免耕推广的关键配套技术。通过研究杂草处于不同麦茬环境中,使用不同喷洒喷头施用除草剂后杂草对喷洒药液的剂量反应规律,得出不同剂量除草剂对杂草藜的控制效果差异不显著,而稗草在使用不同的除草剂剂量和处在不同的喷洒麦茬环境后呈现出一定的差异,本研究还给出了狗尾草在不同除草剂剂量条件下的剂量反应曲线。     

暖冬气候对大小麦生长发育的影响

近十几年来,全球厄尔尼诺现象频繁发生,气候日趋变暖,气温不断升高,暖冬成为其主要的表现特征.而2006～2007年的冬季则是历史上极为罕见的温暖年,为典型的暖冬气候,冬季气温偏高,对小麦、大麦生长发育带来不利影响.     

麦田禾本科杂草发生特点及防治药剂的研究

近年来,麦田禾本科杂草发生趋势上升,笔者经过对禾本科杂草发生特点的研究,提出了防治药剂和有效剂量,现予以报道,供参考。     

HA对麦田主要除草剂品种控草效果的影响

研究了在HA作为除草剂助剂条件下,4种麦田除草剂不同剂量对6种杂草的控制效果.结果显示,HA对骠马、阔世玛、麦极均有显著增效作用;而对光合抑制剂类除草剂异丙隆具有明显的拮抗作用.     

棉隆土壤消毒防除小麦田杂草的效果及对养分的影响

采用田间试验研究了98%棉隆微粒剂防除小麦田主要杂草的效果,及杂草防除后对氮、磷、钾及水分的影响。结果表明,施用98%棉隆微粒剂防除小麦田杂草效果显著,对菵草(Beckmannia syzigachne)、猪殃殃(Galium aparine L)、牛繁缕[Malachium aquaticum (L.) Fries]、大巢菜(Vicia sativa L.)均有良好防效,总鲜重防效达87.5%～99.5%,优于两种对照药剂。杂草防除后,显著降低了杂草对田间氮、磷、钾和水分的消耗,有效改善了田间的水肥条件。98%棉隆微粒剂处理的小麦田产量达2 970.01～3 123.77 kg/hm2,增产效果显著,产量较清水对照增加28.9%～35.6%,每公顷增收1 532.38～1 886.02元。     

Hyperspectral species mapping for automatic weed control in tomato under thermal environmental stress

This work studied the impacts of variations in environmental temperature on hyperspectral imaging features in the visible and near infrared regions for robust species identification for weed mapping in tomato production. Six major Californian processing tomato cultivars, black nightshade (Solanum nigrum L.) and redroot pigweed (Amaranthus retroflexus L.) were grown under a variety of diurnal temperature ranges simulating conditions common in the Californian springtime planting period and one additional treatment simulating greenhouse growing conditions. The principal change in canopy reflectance with varying temperature occurred in the 480-670 and 720-810 nm regions. The overall classification rate ranged from 62.5% to 91.6% when classifiers trained under single temperatures were applied to plants grown at different temperatures. Eliminating the 480-670 nm region from the classifier’s feature set mitigated the temperature effect by stabilizing the total crop vs. weed classification rate at 86.4% over the temperature ranges. A site-specific recalibration method was also successful in alleviating the bias created by calibrating the models on the extreme temperatures and increased the classification accuracy to 90.3%. A global calibration method, incorporating all four temperature conditions in the classifier feature space, provided the best average total classification accuracy of 92.2% out of the methods studied, and was fairly robust to the varying diurnal temperature conditions.     

2,4-D丁酯麦田除草效果及其对小麦安全性的研究

对小麦2叶1心至拔节前用2，4－D丁酯做茎叶处理的除草效果进行了研究。结果表明：在小麦2叶1心至返青期施用72％2，4－D丁酯乳油对小麦田越年生杂草有理想除草效果。冬前施用2，4－D丁酯对小麦有一定药害，使小麦产量受到影响，用药越早，小麦产量越低。在产量构成因素中，以穗数受药害影响最大；冬后小麦返青至拔节期施用2，4－D丁酯，对小麦产量无影响。     

Systemic acquired resistance,NPR1, and pathogenesis-related genes in wheat and barley

In Arabidopsis, systemic acquired resistance (SAR) is established beyond the initial infection by a pathogen or is directly induced by treatment with salicylic acid (SA) or its functional analogs, 2,6-dichloroisonicotinic acid (INA) and benzothiadiazole (BTH). NPR1 protein is considered the master regulator of SAR in both SA signal sensing and transduction. In wheat (Triticum aestivum) and barley (Hordeum vulgare), both pathogen infection and BTH treatment can induce broad-spectrum resistance to various diseases, including powdery mildew, leaf rust, Fusarium head blight, etc. However, three different types of SAR-like responses including acquired resistance (AR), systemic immunity (SI), and BTH-induced resistance (BIR) seem to be achieved by activating different gene pathways. Recent research on wheat and barley NPR1 homologs in AR and SI has provided the initial clue for understanding the mechanism of SAR in these two plant species. In this review, the specific features of AR, SI, and BIR in wheat and barley were summarized and compared with that of SAR in model plants of Arabidopsis and rice. Research updates on downstream genes of SAR, including pathogenesis-related (PR) and BTH-induced genes, were highlighted.     

浙江省麦田和油菜田杂草发生种类及危害

１９８６～１９８８年在浙江省嘉兴、杭州、金华和温州４个农区,对大小麦和油菜田杂草发生种类和危害程度开展全面系统调查,涉及６个市、２３个县（市）和１个大型农场,计７０００多块样田,取样面积约６６７ｈｍ＾２。调查结果,浙江省大小麦和油菜田共有杂草５０科２７７种,杂草群落结构复杂,危害程度较高,杂草群落组成与地域、地势、土质、前茬作物及耕作习惯等有关。最后提出大小麦和油菜田杂草防除对策和措施,并附浙江省大小麦和油菜田杂草名录。     

小麦抗穗发芽品种资源的筛选

[目的]利用已报道的抗穗发芽共显性STS标记Vp1B3,筛选适宜黄淮麦区和长江中下游麦区种植的抗穗发芽白粒小麦品种。[方法]对57份黄淮麦区和长江中下游麦区的主要品种（系）及地方品种于2007年测定种子萌发指数（GI）,并用标记Vp1B3对选取的品种做PCR扩增。[结果]标记Vp1B3扩增出抗性条带845、569 bp和感穗发芽条带652 bp 3种类型的片段,其频率分别为7.0%、26.3%和66.7%,且3种基因型品种之间的GI值差异均达到极显著水平。[结论]验证了标记Vp1B3能对不同品种的穗发芽抗性进行有效筛选;筛选出2份GI值〈20%的白粒抗穗发芽小麦品种,丰产3号和万县白麦子,可作为穗发芽抗性育种中的有用资源。     

湖北省2000年审定的玉米、大小麦新品种

湖北省农作物品种审定委员会于2000年3月18日在武汉召开第三届第四次常委会议,审定通过了2个玉米新品种鄂玉13、鄂玉14,1个大麦新品种鄂大麦8号,1个小麦新品种鄂麦14.现简介如下,以供各地因地制宜组织示范推广.     

Features of weed component formation in spring wheat crops upon the introduction of No-Till technology

Data on changes in the weed infestation of spring wheat crops during transition to No-Till technology under conditions of the forest steppe zone of Western Siberia are provided. The features of formation of a weed component are revealed depending on the predecessor and the level of agrochemicalization.     

小麦抗穗发芽种质筛选与新品系的抗穗发芽性鉴定

对2007-2008年度国家冬小麦(长江上游组)区域试验和重庆市小麦区域试验的参试品系、部分自育新品系及种质资源,在成熟收获后测定其籽粒发芽卒、种子多酚氧化酶(PPO)活性和邻苯二酚种皮染色值.结果表明,参试品种(系)间籽粒发芽率、多酚氧化酶活性、邻苯二酚种皮染色值存在极显著差异;籽粒发芽率与PPO活性及籽粒邻苯二酚染色值呈极显著的正相关;聚类分析把参试的39份小麦品种(系)分为3类并鉴定出黑粒小麦76、漯珍1号等几份材料具有很强的抗穗发芽能力,可在小麦抗穗发芽育种上应用.     

骠马防除麦田杂草的施用技术

在同等条件下,麦田施用骠马防除杂草,效果优于绿麦隆。试验结果表明,骠马在低用量的药效表现温和,高用量时杀草迅速彻底。使用69克/升骠马水状乳油时,最佳用量为每亩40—50毫升,一般较不施药增产20%—30%,较施用绿麦隆增产10%左右。施用骠马,对小麦前期分蘖有抑制作用,对后期分蘖成穗有促进作用。不同类型小麦品种对骠马的反应不敏感。     

大、小麦籽粒发育过程中锌、镉的转移与积累

综述了大、小麦籽粒发育过程中锌(Zn)、镉(Cd)的转移途径和在籽粒中积累及其影响因素的研究现状,同时讨论了Zn对Cd毒害的缓释效应。有毒重金属Cd在大、小麦籽粒中的积累严重影响其品质和食品的安全性。Zn的化学性质与Cd具有极大的相似性,因此,明确Zn的转移、积累规律对研究Cd向籽粒中的运输及在籽粒中的积累具有重要意义。Zn通过韧皮部转移进入正在发育的籽粒,且受其浓度、环境湿度、蔗糖浓度以及其它微量元素的影响。Cd的转移模式可能与Zn相似,两者可能存在拮抗作用。但是,Cd是否主要通过韧皮部运输进入籽粒、木质部向韧皮部转移的部位,以及影响Cd转移进入大麦发育籽粒的因素仍有待进一步研究。     

水稻穗发芽研究进展

作物收获前的穗发芽是一个严重的全球性农业生产问题。经过漫长的驯化过程,栽培作物的休眠水平普遍低于野生祖先。尽管休眠期的缩短可能提高作物的繁殖代数和农业产值,但过早的休眠释放使作物在成熟收获前发生穗萌发,造成巨大的经济损失。从穗发芽的生理基础、穗发芽相关QTL和基因、穗发芽防控及展望等方面对水稻穗发芽现象进行梳理,认为高含水量是水稻种子萌发和穗发芽的先决条件,该过程中,淀粉酶活性增强和可溶性糖含量升高为穗发芽提供能量,水稻籽粒中植物激素ABA和GA的含量及种子对二者的敏感性是决定穗发芽的关键所在。近年来,穗发芽相关QTL及其功能基因的挖掘为阐明水稻穗萌机理以及培育穗发芽抗性品种提供重要依据。从长远来看,广泛开展水稻种质资源鉴评,尤其在野生稻、地方品种中寻找丢失的休眠基因,并通过分子育种途径聚集此类基因,培育抗穗萌品系（品种）,对于解决穗发芽问题、提高水稻产量和品质、保证国家粮食安全具有重要意义。     

Heredity and gene mapping of a novel white stripe leaf mutant in wheat

Spotted leaf(spl) mutant is a type of leaf lesion mimic mutants in plants. We obtained some lesion mimic mutants from ethyl methane sulfonate(EMS)-mutagenized wheat(Triticum aestivum L.) cultivar Guomai 301(wild type, WT), and one of them was named as white stripe leaf(wsl) mutant because of the white stripes on its leaves. Here we report the heredity and gene mapping of this novel wheat mutant wsl. There are many small scattered white stripes on the leaves of wsl throughout its whole growth period. As the plants grew, the white stripes became more severe and the necrotic area expanded. The mutant wsl grew only weakly before the jointing stage and gradually recovered after jointing. The length and width of the flag leaf, spike number per plant and thousand-grain weight of wsl were significantly lower than those of the WT. Genetic analysis indicated that the trait of white stripe leaf was controlled by a recessive gene locus, named as wsl, which was mapped on the short arm of chromosome 6 B by SSR marker assay. Four SSR markers in the F_2 population of wsl×CS were linked to wsl in the order of Xgpw1079–Xwmc104–Xgwm508-wsl–Xgpw7651 at 7.1, 5.2, 8.7, and 4.4 c M, respectively and three SSR markers in the F_2 population of wsl×Jimai 22 were linked to wsl in the order of Xgwm508–Xwmc494–Xgwm518-wsl at 3.5, 1.6 and 8.2 c M, respectively. In comparison to the reference genome sequence of Chinese Spring(CS), wsl is located in a 91-Mb region from 88 Mb(Xgwm518) to 179 Mb(Xgpw7651) on chromosome 6 BS. Mutant wsl is a novel germplasm for studying the molecular mechanism of wheat leaf development.