水溶性氟乐灵纳米制剂对向日葵列当的毒力及田间药效

向日葵列当Orobanche cumana是一种检疫性恶性寄生杂草。本研究采用透析法制备了一种水溶性氟乐灵纳米制剂(Tf-OR-CC),评价其对向日葵列当的室内毒力和田间药效。种子发芽毒力测定结果表明:在独脚金内酯类似物GR24的诱导下,用5μg/mL Tf-OR-CC处理向日葵列当种子,7 d后表现出良好的抑制发芽活性,列当种子发芽率为28.5%,与对照相比差异显著。消解动态试验表明,Tf-OR-CC消解半衰期比48%氟乐灵乳油延长6.56 d,说明Tf-OR-CC具有一定的缓释作用。田间药效试验结果表明,滴灌施用有效成分含量为75 g/667 m~2Tf-OR-CC 45 d后,向日葵列当寄生率为32.1%,寄生强度为5.3,Tf-OR-CC制剂对向日葵列当的田间防效为36.3%。该方法可为向日葵滴灌施药技术防治向日葵列当提供科学依据。     

我国向日葵列当发生危害现状调查

向日葵列当是危害我国向日葵最严重的杂草。为明确我国向日葵田列当的发生危害情况及防治现状,采用对角线5点取样法对新疆、内蒙古、吉林和河北等主要向日葵种植区进行调查,对向日葵列当的寄生率和寄生强度等数据进行分析。结果表明,向日葵列当在向日葵产区广泛分布,严重危害向日葵的生产,其对食葵的寄生率高于油葵,对抗性品种的寄生率较低。在所有调查地区中内蒙古地区向日葵列当发生最严重,寄生率高达100%,寄生强度达到38.5,单株寄生数量最高,达118株;新疆地区的向日葵列当寄生率居中,吉林、河北向日葵列当发生相对较轻。通过实地调研结合文献报道,对目前国内外向日葵列当的研究进展进行了综述,研究结果为指导向日葵列当防治提供参考。     

向日葵新品种对列当的抗性鉴定

通过田间自然寄生试验,鉴定了2个向日葵新品种对列当的抗性。结果表明,向日葵新品种TP3313列当寄生率为0%,抗寄生指数为1,为免疫品种,其他病虫害发生为害较轻,产量为261.1 kg/667m~2,具有较高的推广应用价值;TP3314向日葵列当的寄生率为0.4%,寄生指数为0.99,为高抗品种。但向日葵菌核病发生较重,产量为219.6 kg/667m~2,在生产应用过程中,应注意向日葵菌核病的防控。     

室内条件下向日葵列当和弯管列当在三种不同寄主上寄生能力的比较

以向日葵列当Orobanche cumana Wallr.和弯管列当O.cernua Loefl.为研究对象,利用已有的室内寄生体系来研究两种列当在向日葵、烟草、番茄3种寄主上的寄生能力。结果表明,向日葵列当在室内条件下不仅能够寄生在向日葵上,同时也可以在烟草与番茄上寄生;但其寄生效率在上述不同的寄主之间存在显著差异,而在相同寄主的不同品系间没有差异。交互侵染的结果表明,在寄主番茄上,弯管列当平均每株寄生的瘤结数量为16.3个,向日葵列当只有2.5个;在寄主向日葵上,向日葵列当的平均寄生瘤结数量为25.2个,弯管列当为27.6个,预示着弯管列当在番茄上寄生效率均显著高于向日葵列当,而在寄主向日葵上,二者寄生效率差异不显著,均能高效寄生在向日葵根系上。上述研究结果将为向日葵列当和弯管列当发生严重地区作物轮作对象的选择提供理论依据。     

向日葵品种抗列当寄生差异性研究

向日葵列当是危害性极大的寄生性杂草,本文从列当高度、株距、寄生深度等方面对13个向日葵品种进行了抗性水平鉴定,并分析了品种间寄生指标的差异。结果表明:列当株高一般在31～60 cm,最高66.5 cm,最低5 cm;寄生数量最多在1～10 cm的范围内,最大株距为68 cm,最小为2 cm;在5～10 cm表土深处向日葵侧根上寄生数量最多,受害也最严重;9个食用向日葵品种中,2个品种免疫,1个高抗,其余为高感;4个油用向日葵品种中1个高抗,其余为易感;不同向日葵品种在寄生率、寄生程度和寄生强度等方面呈显著差异。     

我国新疆焉耆垦区作物轮作种植模式防除列当的有效性研究

本研究以新疆地区危害最严重的向日葵列当和瓜列当为研究对象，通过室内水培试验和室外盆栽模拟轮作试验来探究焉耆垦区轮作模式对两种列当的防除效果。结果表明，室内水培试验中各轮作作物的根系分泌物及萃取相刺激瓜列当种子的萌发率均在20.0%以下，但刺激向日葵列当种子产生的萌发率达到了50.0%以上；室外盆栽模拟轮作试验中，甜菜、小麦、辣椒与加工番茄轮作后，瓜列当的寄生数量未显著降低；但与向日葵轮作后，向日葵列当的寄生数量显著减少了60.0%以上。不同品种甜菜、辣椒和小麦地上部甲醇提取液刺激瓜列当种子的萌发率均低于10.0%，但是刺激向日葵列当种子的萌发率均达70.0%以上。本研究表明新疆焉耆垦区轮作种植模式不能有效防除瓜列当，但模式中的轮作作物均能够有效防除向日葵列当。本研究结果为防除新疆焉耆垦区向日葵列当和瓜列当提供理论依据。     

向日葵播种期对防治向日葵螟和黄萎病的影响

为了明确向日葵不同播期对防治向日葵螟和黄萎病的影响,于2009年5月11日至6月10日在内蒙古巴彦淖尔地区分7个时期(间隔5天)种植食葵和油葵,并系统调查向日葵螟和黄萎病的发生危害情况。结果显示,食葵和油葵的向日葵螟危害率及向日葵螟密度均以5月26日种植的最低,分别为8.00%、4.00%和0.14头/盘、0.16头/盘。随着播种期的推迟,食葵和油葵的黄萎病发病率自5月11日的98.67%和100.00%逐渐降至6月10日的24.00%和32.00%,发病级别从5月11日的2.83级和3.27级逐渐降至6月10日0.36级和0.64级,差异达到显著水平。食葵以5月31日播种的产量最高,而油葵以6月5日播种的产量最高。证明适时晚播可有效减少向日葵螟和黄萎病对向日葵的危害。     

阴山北麓地区向日葵列当生理小种的鉴定及种子的单株纯化

向日葵列当是一种全寄生的种子植物,对向日葵生产造成严重的影响,而选育抗列当品种是目前防控向日葵列当最为有效的防控措施。由于向日葵列当种群存在生理小种分化现象,因此明确不同地区的向日葵列当生理小种的类型以及分布对于抗列当品种的布局非常重要。本研究利用国际通用的向日葵列当生理小种鉴别寄主,对阴山北麓地区的武川县和四子王旗共计7个向日葵地块中采集的列当种子的生理小种进行了鉴定,结果表明除了呼和浩特市武川县头号村采集的向日葵列当样本为E小种外,其他6个不同地点采集到的向日葵列当样本均鉴定为G小种。为了更好地对向日葵品种抗列当水平进行准确的评价,本研究选择了已经鉴定为E、F和G三个小种类型的向日葵列当的样本进行了单株纯化以及扩繁。扩繁得到的列当的种子将用于准确评价向日葵不同的育种材料和品种对列当不同生理小种的抗性水平。     

向日葵抗列当水平室内鉴定体系准确性评价及不同品种抗列当水平鉴定

向日葵列当是一种寄生在向日葵根部的寄生性种子植物。向日葵被列当寄生后表现为植株矮化、花盘减小、产量急剧下降,含油量和蛋白含量也明显降低,严重时可导致向日葵绝收。利用12份在田间条件下鉴定出抗性水平的向日葵品种对室内建立的列当寄生体系(培养皿滤纸体系)鉴定结果的准确性进行了评价。在此基础上对供试的80份不同向日葵品种的抗列当水平进行了室内鉴定。结果表明,供试的47份食葵品种中以TP3313为代表的3份品种表现为免疫水平,所占比例为6%;而以JK601为代表的11份品种呈现高抗水平,占比为24%;其余品种均呈现感病和高感水平。供试的33份油葵品种中以F917为代表的11份品种表现为免疫水平,所占比例为33%;而以赤CY102为代表的14份品种呈现高抗水平,占比为43%;感病和高感水平品种占比为3%。整体看来,油葵品种对列当的抗性水平显著高于食葵品种。     

向日葵抗列当品种(系)筛选及其应用评价

为了全面评价不同向日葵品种(系)对列当的抗寄生性和其在生产中的应用价值,对‘TP3313’等50个食葵品种(系)、‘内蒙杂4号’等6个油葵品种(系)进行了田间自然寄生试验,结果表明:食葵‘TP3313’为对列当免疫的品种,且病虫害发生较轻,产量相对较高(261.11kg/667m~2),因而具有极高的推广应用价值;‘TP3314’为高抗列当品种,但是受向日葵菌核病危害较重,产量为219.64kg/667m~2;‘SH361-L’、‘SH338-M’等8个品种表现为中感,属耐列当品种(系),并且产量相对较高,在生产中具有一定的应用价值。     

施肥和绿肥翻压方式对旱地冬小麦生长及土壤水分利用的影响

通过田间试验研究渭北旱原不同施肥处理(不施肥;40 kg P2O5/hm2;豆科绿肥专用肥30 kg/hm2)对夏闲期豆科绿肥生长和后茬小麦生长的效果,探讨了夏季豆科绿肥翻压方式(提前翻压、提前覆盖,播前翻压和不种绿肥即夏季休闲)对后茬冬小麦产量及水分利用的影响。研究表明:与不施肥处理相比,豆科绿肥专用肥显著提高绿肥盛花期地上部生物量,但对根系生长没有明显作用;施用磷肥则更有利于绿肥根系生物量的提高;施用绿肥专用肥和磷肥处理的后茬小麦产量较高,特别是绿肥提前翻压时。绿肥提前翻压时冬小麦分蘖数较高、春季总茎数较高、单位面积穗数较高,产量显著高于绿肥提前覆盖、播前翻压和不种绿肥处理,水分生产效率显著高于不种绿肥处理。从绿肥翻压、小麦播前直至小麦拔节期,绿肥翻压方式的3个处理土壤0~200 cm剖面水分含量与休闲处理始终有明显差异。提前翻压处理与提前覆盖、播前翻压处理的差异主要在40 cm以上土层。     

不同氮肥运筹对冬小麦产量、蛋白质及其组分的影响

2003～2004年在大田节水栽培条件下,研究了3个施氮水平(157.5 kg/hm2、226.5 kg/hm2、295.5kg /hm2)下氮肥一次性底施与分次施用(底肥 拔节期追肥)对两个小麦品种(强筋麦济南17与中筋麦石家庄8号)品质和产量的影响.结果表明:节水栽培条件下不同氮素水平及等量氮肥一次性基施与分次施用两小麦品种产量差异不显著,过量施用氮肥产量反而有所下降;施氮越多,氮肥生产力越低;不同处理对两品种小麦籽粒蛋白质及其各组分的影响也同样没有达到显著水平.     

Factors affecting the efficacy of Orobanche cumana chemical control in sunflower

Broomrapes ( Orobanche spp.) are root parasites, causing severe damage to vegetable and field crops. Their early in situ detection for efficient control is crucial but difficult, because of their sub-surface development. Minirhizotron technology enables the in situ observation of host–parasite interactions. The initial underground development of Orobanche cumana on sunflower roots and its control with imazapic were investigated. Imazapic (2.4 g active ingredient ha⁻¹) was applied post-emergence on sunflower at the eight-true-leaf stage, when O. cumana attachments were first observed. No viable or new attachments were detected on roots of the treated sunflower after herbicide application. However, within the same time frame, the already existing O. cumana attachments in the non-treated controls continued to develop and new attachments appeared. Orobanche cumana shoot emergence was correlated with growing day-degrees (GDD, d °C). This correlation was quantified by a four-parameter logistic equation. Control efficacy was affected by depth and number of parasite attachments per minirhizotron camera frame: it was highest in the topmost layer, and decreased with depth and number of attachments. The results obtained in this study emphasise the need to develop a decision support system based on GDD that should be validated under long-term field conditions.     

播种期对农牧交错带马铃薯生长发育和产量形成及水分利用效率的影响

为了研究不同播种期对农牧交错带马铃薯生长发育和产量形成以及水分利用效率的影响,为农牧交错带马铃薯适期播种和高产栽培提供科学依据,采用随机区组排列设计,分析了超早播(4月28日)、早播(5月8日)、中播(5月18日)、晚播(5月28日)和超晚播(6月8日)五个播期下马铃薯生育期、形态指标、产量形成和水分利用效率的变化情况。结果表明:播种期对马铃薯生育期、株高和叶面积指数影响显著。随播期推迟,马铃薯生育期缩短,播期每推迟10 d,生育期平均缩短6 d,而生殖生长期在总生长期中的比例增加,超早播和超晚播处理下分别为45%和59%。超早播和早播马铃薯地上部干物质积累显著低于其余播期,不同播期处理薯块鲜重增长符合Logistic生长曲线,播期间马铃薯总产量、大薯产量和大薯率差异均达显著水平,其中中播、晚播和超晚播产量差异不显著,平均达21 593 kg/hm2,超早播和早播产量平均为15 181 kg/hm2。马铃薯水分利用效率随播期推迟增加,超早播为45.2 kg/(hm2.mm),超晚播为86.3 kg/(hm2.mm)。建议农牧交错带马铃薯适宜播种期安排在5月中下旬。     

Effect of sowing dates and fertilizer on the severity of stem borer (Busseola fusca Fuller,Lepidoptera: Noctuidae) on sorghum in Eritrea

The influence of sowing date and fertilizer application on the incidence anddamage ofthe maize stemborer (Busseolafusca Fuller) in sorghum(Sorghumbicolor L.) was investigated at the Halhale Research Centre in Eritrea during 1997 - 99. The trials were conducted in a splitplot design with sowing date as the main plot and fertilizer as subplots. There were six sowing dates at an interval of 15 days starting fromearly April tomid-June. There were fertilized and unfertilized subplots. Data on larval count, per cent infestation, per cent deadheart, heading and maturity dates, plant height and yield were recorded for each plot. Fertilizer had no effect on the incidence and damage of the stem borer (B. fusca). There was no interaction between fertilizer and sowing dates on the larval population and damage by stem borers. Sowing date had a significant effect on stem borer incidence and damage levels. Early sowing dates (April 1 and 15) had a significantly lower number of larvae, infestation, deadheart and gave higher yields compared with the other sowing dates while late sowing dates (mid-May- mid-June) resulted in significantly higher infestation and damage. The highest infestation and damage were recorded from mid-May sowings. High stem borer infestations in delayed sowing was due to the coincidence of the susceptible stage of the crop (3 - 6 weeks after germination) with high populations ofstemborer larvae fromthe first generationin late June and July. Mid- and late sown crops were also later attacked by the second generation at the grain-filling stage in September- October. These results indicate that early planting (April) is effective in reducing stem borer damage on sorghum in the highlands of Eritrea.     

Sunflower Response to Application of L-Ascorbate Under Thermal Stress Associated with Different Sowing Dates

Unlike edaphic factors, it is difficult to control climatic conditions and their changes that affect plant growth and development. To deal with such posture, farmers have to cultivate their crops at the right time. From this point, over two–year of 2014 and 2015, a field experiment was performed at El-Nubaria region, El-Behaira Governorate, Egypt, to assess the response of sunflower to different combinations between sowing dates (early, mid and delayed) and ascorbic acid treatments (with ascorbic acid and without ascorbic acid). Ascorbic acid was sprayed at 30, 40 and 50 days after sowing. The results showed that sowing sunflower in mid sowing (May 21) achieved the highest values of cumulative heat units utilization efficiency as well as all growth and yield traits, while the lowest values were recorded under the delayed sowing date (June 21). Application of ascorbic acid was effective for promoting growth and yield traits under all studied sowing dates. Ascorbic acid achieved 11.6, 10.1, 10.7 and 12.9% increases under early sowing, and 9.5, 6.6, 8.6 and 10.3% increases under delayed sowing in head diameter, seed weight plant^?1, seed yield and oil yield, respectively. Comparing to mid sowing?×?without ascorbic acid, application of ascorbic acid alleviated seed yield losses associated early sowing from 15.7–6.6% and from 23.0–16.4% with delayed one. In conclusion, for remediating the thermal stressful impacts of early or late sowing of sunflower, farmers are advised to treat crop plants with ascorbic acid to avoid yield losses.

     

Effect of sowing date and host resistance on the establishment and development of Orobanche crenata in faba bean and common vetch

The effect of early and late sowing dates on the establishment of Orobanche crenata Forsk. (crenate broomrape) in resistant and susceptible cultivars of faba bean (Vicia faba L.) and vetch (Vicia sativa L.) were studied over four seasons in southern Spain. Differences in establishment, development and shoot emergence of the parasite were compared. With resistant faba bean and vetch cultivars, there was reduced attachment and shoot emergence of O. crenata with all sowing dates. Susceptible cultivars were more severely affected by the parasite with early sowing. Orobanche crenata development was also delayed in resistant cultivars. Crop yield, estimated by the number of pods per plant, decreased with late sowings. The combined use of resistant cultivars and early sowing is a useful tool as part of an integrated control strategy. Resistant cultivars allow early sowing (with low O. crenata attack), thus avoiding yield losses due to the short crop cycle with late sowing.     

大豆蚜的系统最优控制研究

１９９３￣１９９６年作者以系统最优控制为技术原理,采用逐步逼近法和正交优化法,研究了豆田１１种可控因素对大豆蚜,天敌和产量的综合效应。根据既控虫增产又保护生态的原则,综合评价可控因素,提出大豆蚜系统最优控制：大豆与玉米同穴（４：１式）或间作（９：２式）、鲁豆４号６月１０日前后播种、１８００ｇ／ｈｍ＾２微肥拌豆种,Ｎ４５ｋｇ／ｈｍ＾２,Ｐ２Ｏ５ ６０ｋｇ／ｈｍ＾２、Ｋ２Ｏ１５０ｋｇ／ｈｍ＾２、有机肥