高海拔地区大葱主要病虫无公害防治

近年来，依托贵州省夏秋反季节无公害蔬菜生产示范基地建设项日和毕节地区数万hm^2蔬菜高产示范工程的实施．黔西北高海拔地区的大葱栽培得到了长足发展，种植面积不断扩大，品种日益丰富。为进一步指导好蔬菜中产发展．推进农业产业结构调整，促进农业增效和农民增收，笔者通过专题调查研究、认真开展试验和查阅大量文献．对高海拔地区大葱主要病虫害无公害防治技术作了一些探索和研究。     

恩施高山白菜黑斑病的发生为害及综防措施

恩施市新塘乡地处高海拔山区,具有良好的生态环境条件和夏秋凉爽的独特气候资源,是发展夏秋反季节白菜生产的理想区域。自二十世纪九十年代开始发展高山夏秋反季节白菜生产以来,常年种植面积稳定在600多hm2。由于连年种植,再加上栽培管理措施不当,外来品种的不断引进等因素的影响,近年来,白菜的各种病虫害发生和为害逐年加重,而且发病特点产生了明显的变化。其中白菜黑斑病由原来的次要病害逐步上升为当前的主要病害之一。     

神农架白菜病毒病发生及无公害防治对策

神农架地处鄂西北山区,区内地势海拔相差较大,是我国南北气候过渡带,气候复杂。随着种植业结构调整,神农架已建成蔬菜、干果、中药材、茶叶、畜牧5大优势农产品板块,高山反季节蔬菜成为农民增收的亮点,其中春夏大白菜在我区中、高海拔区域大量发展,种植面积逐年增长,到2007年,已累积发展中、高山春夏大白菜2000hm2,但因发生多种病虫害,尤其是病毒病发生普遍,严重影响了神农架蔬菜产业的发展,为了促进蔬菜板块建设,增加农民种菜收入,我们通过近两年调查大白菜病毒病的发生情况,分析其产生原因,提出无公害防治对策。1发生情况经田间调查发现,…     

瓮安县夏秋西葫芦病毒病的发生及防治

瓮安县位于贵州中部,黔南北部,属亚热带季风湿润气候区,平均海拔1 028 m,年均温13.6℃,适宜发展夏秋反季节蔬菜.2003年,随着产业结构调整的深入,夏秋反季节商品蔬菜种植面积增大,西葫芦成了瓮安县夏秋反季节蔬菜主栽品种之一,但由于夏秋温度高,干旱少雨天气多,西葫芦病毒病发生危害重,特别是在海拔1 100m以下的秋季西葫芦,发病田块和病株率都达100%,严重影响了西葫芦的产量和品质,农民损失惨重.西葫芦病毒病成了夏秋反季节蔬菜生产的一大障碍,因此,种植西葫芦必须搞好病毒病的防治.     

贵州铜仁地区2005年菜青虫发生特点及防治技术

菜青虫属于鳞翅目粉蝶科．是铜仁地区甘蓝上的主要害虫之一。近年来随着铜仁地区农业种植结构的调整和农民种植蔬菜积极性的提高，增加了蔬菜复种指数，蔬菜作物种植面积扩大．特别是反季节蔬菜（结球甘蓝、花椰菜、苤蓝）种植规模的扩大，已成为农民经济收入的主要来源。由于品种多、茬口多，高山蔬菜的发展，为害虫的发生和危害提供了有利的条件，致使菜青虫的发生和危害越来越重，损失大，严重影响了蔬菜的产量和品质，成为蔬菜生产的一大障碍。2005年地区植保站开展了对菜青虫在甘蓝上的发生规律及防治技术研究。     

信息荟萃

1.反季节栽培。如:夏季用遮阳网覆盖降温,栽培大白菜、花椰菜、萝卜等耐阴蔬菜;春、夏季栽培空心菜、茄子、瓜类等;在冬季通过大棚来种植反季节蔬菜。 2.软化栽培。即蔬菜长到一定程度时,设置半暗或黑暗环境,并保持适当的温湿度,让蔬菜植物在少见和不见光的条件下生长。此方法栽培的蔬菜叶     

高山结球甘蓝害虫发生消长特点及防治技术

高山蔬菜是海拔 1 400～ 2 000 m地区利用夏季凉爽、昼夜温差大的自然条件开发的反季节蔬菜.因其种植季节和地理位置的差异,高山蔬菜害虫发生为害与平原城郊特点不同.为此,我们于 2000～ 2002年,在长阳县火烧坪乡高山蔬菜基地对主栽品种结球甘蓝主要病虫的发生消长动态进行了系统试验观察和研究.为确保高山蔬菜的质量与安全,根据高山结球甘蓝的栽培特点和害虫为害特点,提出相适应的无公害综合防治技术.     

夏秋反季节无公害蔬菜病虫害规范化防治技术

无公害蔬菜是指蔬菜产品中的有害物质(包括农药残留、重金属、有害生物等)达到国家有关标准,对公众身体健康没有危害的蔬菜产品.在夏秋种植反季节无公害蔬菜,受高温高湿天气影响,各类病虫害都会同期发生,靠单一的技术难以压控蔬菜病虫的危害,极易造成蔬菜农药污染.要获得优质的无公害蔬菜,就必须实施规范化防治技术.笔者于2003年在桐梓县九坝镇实施夏秋反季节无公害蔬菜33.3hm2,应用规范化技术,对蔬菜病虫害进行综合防治示范.通过实施,降低了农药的用量,杜绝了使用高毒、高残留农药,减少了蔬菜中农药残留,解决了蔬菜中的农药污染,使蔬菜获得高产优质,保障了消费者的安全.     

会仙镇无公害蔬菜病虫害综防对策

临桂县会仙镇蔬菜种植面积逐年扩大，品种日益增多，复种指数不断提高，据统计，2004年全镇蔬菜播种面积2333hm^2，其中反季节蔬菜如春夏大白菜、夏秋番茄、秋四季豆、秋黄瓜等播种面积943hm^2。由于目前蔬菜病虫害的防治仍以化学防治为主，所以化学农药污染的问题严重。不少菜农不能正确识别病虫害，缺乏植物保护基本知识和病虫害综合防治技能，     

神农架林区发生番茄细菌性髓部坏死病

神农架林区平均海拔高度是1 000m左右,适合种植高山反季节蔬菜.当地政府为保证农民经济多元化,除发展旅游业外,还积极推行"一乡一品"式的高山反季节蔬菜种植模式,番茄作为主要的蔬菜品种得到很多乡镇的推广种植.在番茄的推广种植过程中,遇到的最大问题是番茄病害问题.以神农架林区木鱼镇为例,推广以前番茄种植是零星小面积种植,品种也是当地种植了多年的品种,病害问题不怎么突出,但2004年推广"一乡一品"种植模式后,未对引进的番茄新品种进行试种,就大面积推广,当年就出现病害问题(番茄细菌性萎蔫病).由于不知道造成番茄病害病原的种类,当地科技工作者无法制定正确的防治方法,以致出现盲目用药的现象,并且番茄产量连续两年损失60%以上,严重的损失达到90%.为了确诊该病害病原和找出有效的防治措施,作者应邀对该病害进行调查与研究,结果简报如下.     

Growth and reproduction of Cyperus esculentus L. and Cyperus rotundus L.

The growth of both species (as characterized by their total dry weight, inflorescence dry weight, root and rhizome dry weight and number of shoots per pot) was similar, but they differed in the manner in which the dry weight was partitioned to reproductive structures. Each species partitioned less than 2% of its dry weight into floral formation. However, yellow nutsedge (Cyperus esculentus L.) partitioned only 28% of its dry weight to tubers, whereas purple nutsedge (C. rotundus L.) partitioned 50% of its dry weight to fewer and larger tubers. The allocation of dry weight to reproductive structures was related to changes in day-length. Yellow nutsedge tuber formation increased as day-length decreased from 14.5 to 12.5 h, while floral formation did not begin until the day-length dropped below 14 h. Purple nutsedge formed inflorescences earlier and production continued throughout the remainder of the study, but tuber formation was curvilinear and accelerated as the day-length decreased.     

Competitive growth of Echium plantagineum L. and Trifolium subterraneum L.

Echium plantagmeum is a widespread, persistent, and often dominant votunteer species in southern Australia. In pastures. it commonly grows with Trifolium subterraneion. This paper describes glasshouse studies investigating the effects of soil fertility. plant density. sward composition, defoliation frequency. and delayed estabilishment of t. subserraneum on the growth of E. pluntagineum and T. subterraneum when grown in pure swards and in mixtures. Generally. herbage production of swards was increased by the presence of E. plantagineum. the addition of nutrogen and phosphorus fertilizers, and increasing density, It was decreased by defoliation. E. pluntagineum plants generally produced more shoots and roots than did T. subterraneum. Both species responded. E. plantiagineum generally more than T. subterraneum. to added phosphorus and nitrogen fertilizers. Both species showed a non-linear reduction in plant size as plant density of the sward was increased. especially during early growth. E. plantagineum was, however. more plastic in its response to density than T. subterraneum. Defoliation reduced the plant weight of both species. more for E. plantagineum than for T. subterraneum. In mixtures. there was little competition between the two species during early growth. when swards were defoliated and when both species established at the same time. T. subserraneum was, howerver. sometimes suppressed during later growth if swards were undefoliated. if soil fertility was high. and if E. plantaginteum established before t. subserraneum. Such competition appeared to be between shoots rather than between roots. In the field. E. plantagineum is likely to be fovoured in undergrazed situations, where soil fertility is high and when false or early seasonal breaks allow it to establish earlier than t. subterruneum. Its high productivity under a wide range of pasture situations - especially in autumn and winter when pasture availability is ofter critically low and the fact that it is relatively nutritious and readily eated by stock suggest that it is a useful pasture species.     

The nutritive value of Echium plantagineum L. and Trifolium subterraneum L.

Echium plantagineum is a widespread, persistent, highly productive and often dominant species in southern Australia. In pastures, it usually occurs with Trifolium subterraneum. which is commonly regarded as a valuable forage species. However, there is considerable controversy over the value of E. plantagineum as a pasture species. In this study, the nutritive value (dry matter content, in vitro digestibility, nitrogen content) of herbage of E. plantagineum and T. subterraneum generally was similar at any time during the year. It is concluded that E. plantagineum is a useful forage species because it is highly productive, is readily eaten by grazing stock and has a relatively high nutritive value.     

Field emergence of Lamium amplexicaule L. and L. purpureum L. in relation to the annual seed dormancy cycle

Seedling emergence of Lamium amplexicaule L. and L. purpureum L. was monitored in field plots tilled at various times during the growing season, and the number of viable seeds in the soil was determined. In plots tilled in early spring, only seeds of L. amplexicaule, germinated, but seeds of both species germinated in the same plots in autumn without further disturbance. Additional seeds of L. amplexicaule, but not of L. purpureum, germinated the following spring. In plots tilled in late spring and summer, seeds of L. amplexicaule germinated in autumn and the following spring, whereas seeds of L. purpureum germinated only in autumn. The number of viable seeds in the top 13 mm layer of soil ranged from 189 to 1216 m^?2 for L. amplexicaule and from 131 to 854 for L. purpureum. These field results support those obtained in previous glasshouse-laboratory physiological studies on the annual dormancy cycle in the two Lamium species. Levée au champ de Lamium amplexicaule L. et L. purpureum L. par rapport au cycle annuel de la dormance des graines La levée de jeunes plants de Lamium amplexicaule L. et L. purpureum L. a été observée sur des parcelles cultivées à différentes époques de la saison de végétation et le nombre de graines viables au sol a été déterminé. Sur les parcelles cultivées en début de printemps, seules les graines de L. amplexicaule ont germé, mais des graines des deux espèces ont germé en automne sur les mêmes parcelles, sans cultivation ultérieure. Au printemps suivant, une nouvelle germination a été constatée chez L. amplexicaule mais pas chez L. purpureum. Sur les parcelles cultivées en fin de printemps et en été, des graines de L. amplexicaule ont germé en automne et aussi au printemps suivant, tandis que les graines de L. purpureum n'ont germé qu'en automne. Le nombre de graines viables dans les premiers 13 mm de la surface du sol allait de 189 à 1216 m^?2 pour L. amplexicaule et de 131 à 854 pour L. purpureum. Ces résultats sur le terrain confirment ceux obtenus dans des études physiologiques sur le cycle annuel de dormance chez les deux espèces de Lamium, menées préalablement en serre et au laboratoire. Ueber dus Auflaufen von Lamium amplexicaule L. und L. purpureum L. in Bezug auf den Jährlichen Zyklus der Samenruhe unter Feldbedingungen In Parzellen, die zu verschiedenen Zeitpunkten während der Vegetationsperiode einer Boden-bearbeitung unterworfen worden waren, wurde sowohl das Auflaufen der Keimlinge von Lamium amplexicaule L. und L. purpureum L. registriert, als auch die Anzahl lebenfähiger Samen festgestellt. Nach Bodenbearbeitung im frühen Frühling keimten nur Samen von L. amplexicaule; im Herbst keimten in denselben Parzellen jedoch Samen beider Arten, sofern der Boden nicht mehr bewegt worden war. Weitere Samen von L. amplexicaule, nicht aber von L. purpureum, keimten im folgenden Frühling. In Parzellen, die im späten Frühling und im Sommer bearbeitet worden waren, keimte L. amplexicaule im Herbst und im folgenden Frühling. Während L. purpureum nur im Herbst keimte. Die Anzahl lebensfähiger Samen m^?2 in den obersten 13 mm des Bodens bewegte sich zwischen 189 und 1216 für L. amplexicaule und zwischen 131 und 854 für L. purpureum. Diese Feldresultate bestätigen Ergebnisse von Gewüchshausstudien über den jährlichen Zyklus der Samenruhe der beiden Lamium-Arten.     

Establishment and growth of Senecio jacobaea L. and Senecio erucifolius L. in grassland

Senecio erucifolius L. (hoary ragwort) has become conspicuous on roadside verges in southern England. Like Senecio jacobaea L. it is poisonous, so it might be a threat to animal production. In boxed swards the growth of S. jacobaea was less adversely affected by the greater competition from grass with a high level of nitrogen fertilizer than was the growth of S. erucifolius. Also, young S. jacobaea plants showed a much greater ability to regrow after their shoots had been cut at ground level. In a range of grassland managements S. jacobaea established better from seed than did S. erucifolius. Establishment of both species on molehills was poor because of the likelihood that the seedlings would be disturbed or even buried by fresh mole activity. Ten months after sowing, seedlings of S. jacobaea had persisted well in the higher nitrogen environment of ex-cow-dung patches, whereas S. erucifolius had not. Under intensive sheep grazing, in the absence of fertilizer, transplants of S. erucifolius had much greater root dry weights than did those of S. jacobaea. Also, in regrowth after cattle grazing on a fertilized sward, S. jacobaea plants had greater shoot dry weights than did S. erucifolius. Thus, although S. erucifolius can establish from seed in bare patches in an intensively grazed sward it is likely to be less persistent than S. jacobaea if the gaps are ex-dung patches or if nitrogen fertilizer is applied.     

Interference of Sinapis arvensis L. and Chenopodium album L. in spring rapeseed (Brassica napus L.)

Interference of Sinapis arvensis L. (wild mustard) and Chenopodium album L. (lamb's-quarters) in spring rapeseed (Brassica napus L.) was studied under field conditions in 1983 and 1984. Both weed species interfered with rapeseed early in the growing season, causing significant reductions in rapeseed dry weight by June of each year. Sinapis arvensis caused greater rapeseed grain yield reductions than did C. album. With weed densities of 20–80 plants m^?2, rapeseed grain yield reductions ranged from 19 to 77% with S. arvensis but only 20 to 25% with C. album. Rapeseed yield reductions caused by mixtures of both weed species ranged from being less than to being equal to the sum of reductions caused by each weed alone, depending on the weed density and year of study. Both weed species were prolific seed producers capable of returning large quantities of seed to the soil. With weed densities ranging from 10–80 plants m^?2, S. arvensis produced 5700–30 100 seeds m^?2 while C. album produced 3100–63 600 seeds m^?2.     

Factors affecting seed germination of Echium plantagineum L. and Trifolium subterraneum L.

Echium plantagineum L. is a widespread, persistent, and often dominant volunteer species in southern Australia. This paper describes laboratory and field experiments investigating seed germination in E. plantagineum and a commonly associated species, Trifolium subterraneum L. In the laboratory, E. plantagineum germination was favoured by relatively high temperatures, and the seed showed considerable innate and temperature-enforced dormancy. In the field, this dormancy appeared to prevent some germination in response to rainfalls immediately after seed formation, and permitted sporadic germination during summer and autumn in subsequent years. In 1972 and 1974, both species emerged well in autumn whilst E. plantagineum was favoured in summer and T. subterraneum was favoured in winter. No seedlings emerged in spring. Emergence appeared to be controlled primarily by moisture availability and temperature but also was affected by cultivation and removal of soil-surface litter. The results of these seed germination studies show that E. plantagineum is well adapted to persist in a Mediterranean-type climate, and will be favoured in years with early seasonal breaks. T. subterraneum is likely to be favoured with later breaks.     

Growth, development and nutrient accumulation in Senecio vulgaris L. and Chenopodium album L.

Growth, development and nutrient accumula tion in Chenopodium album and Senecio vulgaris grown in pure and mixed stands were investi gated through several experiments conducted under glasshouse conditions. Results showed that the two weeds were different in their growth, development and tissue concentration and accu mulation of mineral elements. The mean concen trations of nitrogen, phosphorus, potassium, calcium and magnesium in shoots of C. album were higher than those of S. vulgaris, while root concentrations of nitrogen, potassium and mag nesium were lower for C. album. Marked dif ferences between the two weed species in their responses to different potassium levels were found. C. album had a high specific requirement for potassium while the reverse was true for S. vulgaris. The competitive ability and accumula tion of nutrients by C. album appeared to be greatly dependent on the availability of high potassium levels in the media.     

不同光照和温度下白花鬼针草和金盏银盘种子萌发研究

通过在人工培养箱内模拟环境条件,探讨了不同光照和温度对白花鬼针草和金盏银盘种子萌发的影响,结果表明：光照和温度不是白花鬼针草种子萌发的必要条件,白花鬼针草种子萌发的温度适应范围比金盏银盘宽,在15＇12／10oc、20℃／15℃、25℃／20℃、30℃／25oC、35℃／30℃、40℃／35℃下均能萌发,在15％／10气、20％／15℃、25％／20℃、30~E／25℃时萌发率均达94％左右,金盏银盘种子在40％／35℃时不能萌发;温度影响白花鬼针草和金盏银盘种子萌发高峰的出现时间及峰值大小,而光照不影响。