新疆甜菜田杂草危害与防治

本文阐述了新疆甜菜田杂草种群结构、消长规律及危险性，提出了以“农业措施为基础、化学除草为中心、人工除草为补充”的综合防治措施：一是合理轮作；二是土地深翻将杂草种子埋于土壤深层；三是清除田边、地头、渠边杂草，以免种子传播；四是地膜覆盖栽培甜菜可制约杂草生长；五是科学合理轮换使用化学除草剂。     

新疆糖区甜菜主要病虫草害的防治

系统地概述了新疆糖区近年来甜菜生产上发生的主要病虫草害,并分别提出了相应的防治措施,对于甜菜种植者在生产中及时有效地防治各种甜菜病虫及杂草危害,实现增产增收具有积极的指导意义。     

寒地水田杂草发生特点及防治对策

掌握寒地水田杂草发生种类及优势种群,对制定杂草综合治理方案,科学选用化学除草及其配套技术具有指导意义。本文对寒地水田杂草发生情况进行调查。结果表明寒地水田杂草种类主要有13科27种,相对密度较大的有稗草、扁杆藨草、狭叶慈菇等十余种,根据杂草发生特点、群落结构制定有效的防治措施。     

大豆田杂草种群普查及防治

大豆田的杂草以禾本科、苋科杂草为主,优势种主要有马唐、马齿苋、狗尾草、蟋蟀草、反技苋等。在防治过程中要农业防治和化学防治相结合。     

黑龙江省甜菜长柄象的发生与防治

甜菜长柄象(Mesagroicus sp.)是黑龙江省甜菜苗期主要害虫之一,在安达、大庆、肇东等地发生数量很大,占79.95％,是危害甜菜的象虫优势种及防治对象。甜菜长柄象属鞘翅目象(虫甲)科。该虫除危害甜菜外,还危害玉米、大豆等作物,同时也加害苍耳、荞麦蔓、萹蓄等杂草。主要以成虫危害甜菜幼苗,咬食幼嫩的子叶及真叶造成甜菜缺苗,甚至毁种。笔者从1978年起对该虫的分布、危害、生物学特性等作了调查研究,并经过田间药剂防治试验与示范,提出了该虫的化学防治新方法。     

大豆田杂草种群普查及防治

大豆田的杂草以禾本科、苋科杂草为主，优势种主要有马唐、马齿苋、狗尾草、蟋蟀草、反技苋等。在防治过程中要农业防治和化学防治相结合。     

黑龙江省双城地区甜菜低产低糖原因的初步探讨

用三年的调查研究,看出影响双城地区甜菜低产低糖的原因为:气候条件的影响主要有雨量、温差、日照,其中以降雨为主要因子;土壤肥力的影响,主要为施肥不科学,轮作不合理;栽培技术跟不上去.表现为差,大垄稀植,田间管理差;还有病虫为害严重等。采取的几项措施:搞好选茬、轮作、整地;增施有机肥和磷肥;提高播种质量,加强田间管理;合理密植,防治病虫害;加强甜菜站系统的农业技术培训等.     

甜菜夜蛾在江苏沿海农区的发生与防治

本文从暴发频率大幅度提高,发生强度显著增加、防治难度大,效果差、预测预报的准确率低和为害损失的惨重等5个方面系统阐述了甜菜夜蛾在江苏沿海农区发生的新特点;并且提出了从提高成虫监测的准确性入手、密切注视甜菜夜蛾的发生动态,重点推广农业综合措施,恶化甜菜夜蛾的生存环境,改进施药方法,提高甜菜夜蛾的防治效果等适应江苏沿海农区甜菜夜蛾综合防治的对策.     

甜菜象虫药剂防治研究

甜菜象虫为东北、内蒙古.新疆及山东等甜菜产区苗期主要害虫,危害甜菜严重,据1979～1980年在黑龙江省调查,危害甜菜象虫有8种之多,其中以甜菜长柄象、蒙古土象和甜菜象为优势种,每年发生面积有46万亩,毁、补种面积为14万亩以上,使甜菜减产11～25％,为了控制该虫的危害,我们于1980～1982年在黑龙江省安达、肇东及阿城等县用甲基硫环磷、呋喃丹等十余种制剂进行了防治试验和生产示范,其结果如下:     

药剂拌种防治甜菜立枯病试验简报

立枯病是世界性甜菜病害,是影响甜菜保苗的重要限制因素。尤其在气温低、肥力低、整地又较差的地块发生更为严重,一般罹病率在20％～40％,个别严重年份高达60％～80％,生产上造成缺苗、断条甚致毁种。目前,对甜菜立枯病的防治必须以农业栽培措施为主辅以农药防治的综合措施。为探讨防治甜菜立枯病的有效农药及合理的搭配方     

Wildlife pests of California agriculture: Regional variability and subsequent impacts on management

Numerous wildlife species are known pests of California agriculture. Effective management of these pests is required to maximize agricultural production, yet it is unclear how the importance of various wildlife pest species and associated management strategies may vary regionally throughout California. Accounting for these regional differences should yield management programs that are specifically tailored to the regions constituents and should be considered when managing wildlife pests at a more localized level. Therefore, we developed a survey to provide quantitative data on regional differences in research and management needs to better guide future research efforts in developing more effective, practical, and appropriate methods for managing wildlife pests. We found that coyotes were a more common pest in the mountain region, ground squirrels were a greater concern in the central and desert valley region, while birds were most commonly listed as pests by individuals working in multiple regions of California. Coyote damage varied regionally, with livestock depredation the greatest concern throughout most of California, although damage to irrigation tubing and sprinklers was of equal concern in the central and desert valley region. For bird pests, exclusionary devices were the most common and most effective methods of control in the coastal region. Frightening devices were the most commonly used method for bird control in all other regions, although the efficacy associated with frightening devices was considered far lower than their level of use, suggesting that better management options are needed for bird control in these regions. For all wildlife pests, nonlethal control options (e.g., exclusionary devices, habitat modification) were generally preferred in the coastal region while lethal removal options ranked higher in the central and desert valley region (e.g., baiting, burrow fumigation). Efficacy was considered the most important attribute of a control method for all regions, while Integrated Pest Management programs were considered the most effective method for controlling wildlife pests in all regions except for the central and desert valley region. Collectively, the importance of wildlife pests and the perception of associated control methods varied throughout California and reflects the need to consider these regional differences in order to optimize damage management strategies at the regional level.     

Root System Characteristics and Control of Nitrogen Uptake

Summary

In many native ecosystems, acquisition of nitrogen (N) depends on bioavailability of this element at the root surface. However, root system characteristics and how they respond to environmental factors are critical to a better understanding of N acquisition in terrestrial plants. This chapter provides an overview of the recent literature in root system control mechanisms of N uptake. In addition to presenting some of the more recent advances in this area, I have argued that in developing a mechanistic understanding, we must first pay more attention to root characteristics, e.g., longevity, uptake kinetics, and architecture that are often overlooked in studies of N uptake. Experimental approaches and techniques must be developed to monitor these characteristics more routinely along with measurements of the common parameters of root biology, e.g., biomass allocation. Because these root traits often exhibit a considerable amount of tradeoffs relative to each other, it is imperative that they are evaluated collectively rather than singly.     

Weed control and sweet maize (Zea mays L.) yield as affected by pyroxasulfone dose

Pyroxasulfone is a new herbicide being considered for registration in sweet maize in Canada; however, there is still little information on the doses required to provide 90% control of annual grass and broadleaved weeds found in southwestern Ontario. The objective of this study was to determine pyroxasulfone doses that would provide at least 90% control of several economically important weeds, without impacting final sweet maize yield by more than 5% in comparison to a weed-free control. Six field trials were conducted over a two-year period (2007 and 2008) at three Ontario locations to evaluate the effectiveness of pyroxasulfone at doses ranging from 31.25 to 1000 g a.i. ha⁻¹. The doses required to reduce weed biomass by at least 90% (I₉₀) varied by weed species. Doses of 93, 499, and 111 g a.i. ha⁻¹ were required to reduce the biomass by 90% of redroot pigweed, common lambsquarters and green foxtail, respectively. There was greater than 95% control of velvetleaf, large crabgrass and barnyardgrass with 31.25 g a.i. ha⁻¹, the lowest dose tested. Sweet maize yield could not be consistently maintained within 5% of the weed-free control. There are several factors that may have contributed to the reduced yield, including soil texture effects, competition as a result of poor common lambsquarters control, and hybrid sensitivity. These results show that biologically effective weed control with pyroxasulfone may be achieved at lower than proposed doses for several weed species; it remains unclear if this is economically sustainable due to the potential impacts on yield.     

海南普通野生稻的花粉育性观察及杂交亲和性

对海南3个不同居群的普通野生稻(O.rufipogon Griff.)的花粉育性进行了观察研究,并采用荧光显微镜技术观察了转基因水稻花粉在不同居群的普通野生稻柱头上的萌发和在花柱内的生长过程。结果表明,以转基因水稻为对照,3个不同居群的野生稻相互之间花粉可育率在1%水平上差异极显著。用荧光显微镜观察时发现,转基因水稻花粉能在3个居群的普通野生稻的柱头上萌发并能到达胚珠,二者杂交亲和,同时发现,花粉管进入三亚居群胚珠的数目比儋州、万宁居群的数目多,说明相对于儋州、万宁居群来说,三亚居群与转基因水稻的杂交亲和性更高。     

内蒙古马铃薯疮痂病发生与防治途径

2011～2012年对内蒙古自治区18个种薯生产单位和11个马铃薯县(旗、市)进行了马铃薯疮痂病(Streptomyces spp.)实地访问和调查。结果被调查的18个种薯生产单位有疮痂病率83.0%,病薯率0.0%～100.0%,11个县(旗、市)商品薯有疮痂病率100.0%,病薯率0.1%～38.0%。重复使用蛭石生产种薯、商品薯生产田轮作少、发病重。种薯较商品薯疮痂病问题更为严重。品种感病、条件适宜、重复使用蛭石、轮作少和缺乏有效杀菌剂是病害严重的主要因素。分析认为,使用效果显著的蛭石消毒剂或种薯处理剂是内蒙古马铃薯疮痂病防治的最佳途径。     

粗厚山羊草细胞质对普通小麦耐盐性的遗传效应

以具有粗厚山羊草(Aegilops crassa 6x)细胞质的异源细胞质小麦为材料，采用加盐培养基进行幼穗愈伤组织诱导(生长)、盐溶液种子发芽、盐溶液幼苗培养和戍株模拟盐池生长等方法研究了粗厚山羊草细胞质对小麦耐盐性的遗传效应，旨在为小麦耐盐育种提供理论依据和种质资源材料。结果表明：粗厚山羊草细胞质对小麦的耐盐性具有明显的遗传效应，其效应值的性质、大小与核亲本品种的基因型有关，在特定的核质组合中粗厚山羊草细胞质可明显提高小麦的耐盐性。异质系Ae.crassa 6x-鉴26和Ae.crassa 6x-SMH1694在幼穗愈伤组织诱导、种子发芽阶段和三叶期的耐盐性比相应核亲本明显增强。返青期和成熟期的鉴定结果表明，一些经核基因型改良的粗厚山羊草细胞质小麦的耐盐性超过或接近抗盐对照品种科遗26。进一步研究粗厚山羊草细胞质提高小麦耐盐性的遗传机制，必将拓宽小麦耐盐育种途径。     

丹参药材HPLC-DAD指纹图谱稳定性研究

指纹图谱已被认为是中药鉴定和质量控制的有效手段之一,高效液相色谱法也相应成为构建中药指纹图谱的最佳选择之一,但其稳定性一直受到质疑.本研究以丹参为材料,比较不同制备方法下,样品色谱图谱的差异,结果表明:提取温度、时间和溶剂体积微小变化对丹参指纹图谱的相似性没有影响,不同处理间指纹图谱的夹角余弦和相似性系数都在0.9以上.对流动相、检测波长、流速、柱温的研究中也得到了同样的结果.因此认为,HPLC-DAD法用于建立中药指纹图谱的稳定性和重现性好,是一种较为可靠的中药鉴定和质量控制方法.     

Rice striped stem borer, Chilo suppressalis (Lepidoptera: Pyralidae), overwintering in super rice and its control using cultivation techniques

Super rice has the potential to deliver very high yields but is also susceptible to attack by the striped rice stem borer, Chilo suppressalis. In this study, surveys and field trials were performed to examine this problem and efficient ways were found to lower the borer’s population density. It was found that larger super rice plants provided more refuges for borers to evade insecticide contact and had a longer growth period allowing borers to complete their larval development in an intact environment. The current cultivation regime was shown to favour outbreaks of borers. Super rice is harvested leaving tall field stubbles until the following growing season, thus providing food and cover in which borers may successfully overwinter. We found that borer larvae were distributed to a greater height in the plants of super rice than in common rice, making control through agricultural operations more feasible. Burning fields after harvest, which killed 84.5% of borers, seemed the best remedy, though this practice is forbidden in China for ecological reasons. Leaving short stubbles followed by appropriate treatment of the rice straw killed 74.0% of the borer population. In addition, spring irrigation after the pre-pupation dispersal movements of borers killed more than half of the overwintering population. Pre-winter rotary tillage had little effect on borer numbers but enhanced the population reduction effect of irrigation the following spring. Based on the results obtained, efficient control of borers on super rice can be achieved by harvesting leaving short stubbles, followed by rotary tillage and spring irrigation. This regime can reduce the borer population by more than 98%, minimising chemical use and maximising use of a reduced agricultural workforce.     

扁茎大豆光合生理特性及种质改良研究

本文分别在盆栽及大田条件下对中国扁茎大豆不同叶位叶片的空间分布、叶片大小及光合生理特性进行了研究。结果表明,扁茎大豆主茎上叶片的数量明显多于普通型大豆,是普通型大豆的２．２倍,且在主茎上的分布不均匀,上部叶片较为密集。不同生育时期,其光合速率最大的叶片比普通型大豆偏下。上部叶片较小且光合速率较低。同一轮的叶片间光合生理参数也明显不同。     

三类典型茶园昆虫和螨类群落组成和动态的差异

2002年7月～2003年7月,每1～2星期1次,对皖南麻姑山区25年生有机茶园、无公害茶园和普通茶园茶丛、茶丛上空及地表的昆虫和螨类进行了系统的调查。查得普通茶园29018个体,分属于79种41科;无公害茶园35117个体,分属于81种41科;有机茶园12727个体,分属于102种57科。查得有机茶园、无公害茶园和普通茶园中,假眼小绿叶蝉个体数及其占总个体数百分率分别为5176个和40%、14049和40%、17590和60%。蜂类、步甲类、虎甲类、瓢虫类和隐翅甲类是茶园主要天敌昆虫,这几类天敌的种数和个体数在有机茶园、无公害茶园和普通茶园中分别是40种和2620个、33种和1898个、29种和1610个。三类茶园中,3～4月、9～10月物种数较多,11月下旬～1月上中旬种数较少;4～6月个体数较大,7～8月天气炎热、个体数减少,9～10月个体数又增多较大,12月～次年1月个体数较少。普通茶园个体数波动大;无公害茶园个体数最多,由于及时监测和防治,可控制虫害大发生。有机茶园个体数最少而物种数最多。研究认为有机茶园建在山林间,植物相繁盛,生物多样性大,群落的能流路径复杂,稳定性强,涵养了自然控制潜能。