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为制定完善梨避雨栽培害虫高效安全综合防控措施,2017-2019年以露地栽培为对照,系统开展了梨避雨栽培区域性主要害虫发生差异调查分析,结果表明：与露地栽培相比,避雨栽培条件下,可避免梨茎蜂、梨瘿蚊的发生为害,茶翅蝽、梨小食心虫、金龟子类、天牛类等发生程度极显著降低,梨二叉蚜呈百倍以上加重为害趋势,黄粉蚜、二斑叶螨等偶发害虫易蔓延成灾。为此,生产上制定与落实以性喜温暖干燥气候的小虫体害虫为重点的害虫综合防控技术措施。 相似文献
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【导读】我国栽培梨树通常分为5大系统,即白梨、沙梨、秋子梨、新疆梨和西洋梨。近年来,随着我国梨品种更新及种植结构和模式的变更,病毒病为害呈加重趋势。因此,针对梨树病毒病的发生特点,开展相关防控措施研究亦得到有关主管部门的高度重视。培育和栽培梨无病毒苗木是防治病毒病的最有效措施,也是当今果树栽培的重要发展方向。 相似文献
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为明确黄冈地区梨小食心虫发生规律,探索迷向丝结合化学防治对梨小食心虫防控效果,监测了黄冈地区梨园梨小食心虫发生规律,比较了三个密度迷向丝结合化学防控对“双臂顺行式”棚架梨园梨小食防治效果。结果表明,黄冈地区梨园梨小食心虫一年发生5代,越冬代成虫高峰期发生在3月中下旬,第一代成虫发生高峰期为5月中旬至6月初,第二代高峰期6月下旬至7月中旬,第三代高峰期7月底至8月中旬,第四代高峰期8月下旬至9月下旬;495根/km2和660根/km2两个密度结合化学防控对梨小食心虫各个世代迷向率均达到97%-100%,蛀果率均在0.73%以下,防治效果均达到93.13%以上。 相似文献
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１病虫害主要种类及发生特点 江汉平原地区,梨新梢抽生与开花期为３月下旬至４月上旬,新梢生长至第二次生理落果期为４月中旬至４月底。这两个物候期的主要病虫害分别有梨黑星病、梨锈病;梨瘿蚊、梨蚜、梨木虱、梨茎蜂、梨大食心虫、叶螨、梨星毛虫等。梨锈病、黑星病、黑斑病、轮纹病;梨瘿蚊、梨蚜、梨大食心虫、叶螨等;冰雹击伤幼果及缺素性生理病害。这两个阶段是各种病虫从越冬场所转向树体各个部位为害。腐烂病病菌侵入树体为害。梨黑星病病梢、病花丛开始出现。梨轮纹病开始侵染幼果。梨锈病在春雨多时展叶后２０天内最易感染,… 相似文献
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１病虫害主要种类及发生特点江汉平原地区,５月上旬至６月上旬为新梢旺盛生长至果实膨大期,６月中旬至７月中旬为果实继续膨大及早熟果采收期。这两个物峰期的主要病虫害分别有黑斑病、黑星病、轮纹病,梨木虱、叶螨、梨叶瘿螨、梨象甲、梨蚜、梨食心虫、梨网蝽、臭木椿象、蓑蛾、介壳虫、吉丁虫、天牛等及缺素性生理病害和各种杂草;黑星病、黑斑病、轮纹病,梨木虱、叶螨、梨叶瘿螨、梨小食心虫、梨网蝽、刺蛾、蚱蝉、天牛等及缺素症和风灾、渍害、干旱等自然灾害。 这两个阶段梨树进入生长旺盛期,多种病虫为害频繁。黑斑病、黑星病若… 相似文献
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<正> 在桑树栽培过程中,常会见到因各种不良因素的影响而发生桑叶萎蔫脱落现象,造成桑叶产量下降,叶质变劣。近年来,我们通过大田和盆栽试验,观察调查了引起桑叶萎蔫脱落的原因及其萎蔫脱落的特征,简报如下,供参考。一、土壤干旱与桑叶萎蔫脱落当土壤水分低于田间持水量的50%时,新梢便停止生长。当田间持水量降低到40%以下时,就会引起桑叶萎蔫并脱落。从一根枝条看,最先萎蔫脱落的是下部老叶,其次是顶端嫩叶,最后是最大光叶(指4—6叶)。从一片叶子看,先由叶缘开始发焦,逐渐向内发展。叶片随着失水而向叶面方向卷曲,叶色由深转淡,呈灰白色,最后焦枯脱落。 相似文献
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１病虫害主要种类及发生特点 江汉平原梨果实成熟采收期为７月下旬至８月下旬,９月至１１月中旬为采果后管理时期。这两个时期的主要病虫害分别为轮纹病、黑星病、黑斑病、红粉病、梨网蝽、叶螨、梨叶瘿螨、梨小食心虫、天牛、吉丁虫、蓑蛾等;黑星病、黑斑病、腐烂病,梨网蝽、椿象、刺蛾,大青叶蝉、梨蚜等。梨树秋季不正常开花。果实成熟采收期轮纹病、黑星病等病菌侵害易引起烂果,采收时注意防止伤果。梨小食心虫、梨同蝽、梨叶瘿螨等害虫继续为害梨树。天牛为害梨树根颈和树干,影响树体生长使树干坏死。吉丁虫初孵幼虫蛀食枝干皮层… 相似文献
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梨瘿蚊俗称梨芽蛆 ,属双翅目 ,瘿蚊科。我镇梨瘿蚊是 1999年从外地引进梨苗木时随苗木传播进入的新害虫 ,该虫在我镇吴庄果园造成很大为害 ,梨树长势差 ,产量低。笔者从 2 0 0 2— 2 0 0 4年在该园进行了防治试验。1 为害情况 以幼虫为害梨树幼嫩叶片 ,为害叶纵向向内卷曲 ,叶片硬脆不能展开 ,最后变黑枯死脱落 ,有的形成秃枝。叶片大量脱落严重影响叶片的光合作用 ,树体营养生长和生殖生长受到很大影响 ,果实小 ,品质差。树上开秋花长秋叶 ,消耗了树体的营养积累 ,第二年少花甚至无花 ,最终有的树不结果 ,大部分树结果少 ,产量低 ,品质差… 相似文献
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由于一些侵染性病害的影响,浙江省主要梨产区早期落叶现象严重,严重影响了砂梨产业的发展。通过对浙江省杭州市商业梨园主栽品种的田间调查发现,不同品种对病菌的抵抗能力不同。园黄为黑斑病的易感品种,但对炭疽病的的抗性较强;黄花和翠冠较抗黑斑病,但黄花炭疽病的发病率较高;三个品种的锈病发病率没有显著差异。病菌侵染和落叶时间的相关性分析表明：病菌侵染后翠冠和园黄落叶较黄花早;受黑斑病菌侵染的叶片最易脱落,而梨炭疽病菌和梨锈病菌不易引起落叶,仅在后期形成穿孔。总体上园黄早期落叶现象最为严重。受梨黑斑病菌侵染后,叶片诱导POD活性的增加来抵御病原菌的侵染。 相似文献
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《African Journal of Range and Forage Science》2013,30(1-3):52-59
Understanding the impacts of intensity and selection of grazing on the performance of grasses is important in the management of grazing areas. It is especially important in semi-arid environments where, apart from moisture, the levels at which grasses are utilized has a major influence on their persistence in the environment. The effects of selective defoliation and height of defoliation (5 cm and 10 cm stubble heights) on the performance of the grass, Themeda triandra, were investigated in a field experiment for two growing seasons. Performance was measured as tiller production, rate of production, tiller mortality, herbage yield and quality. Tiller production was greater (81 tillers per plant) under non-selective defoliation than under selective defoliation (49 tillers per plant) in the 1995/1996 season. Tiller mortality was higher (66.45%) under heavy selective defoliation than under nonselective defoliation (21.98%). Herbage yield, apart from the control treatment, was high (13.6 g per plant) under light non-selective defoliation. Heavy selective defoliation reduced the nutrient levels (e.g. levels of soluble carbohydrates under heavy selective defoliation were 6 g kg?1 glucose compared to 20 g kg?1 glucose under light non-selective defoliation). 相似文献
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运用纺锤形树型实现宽行密植栽培作为现代梨园的主要生产模式,已经为广大果农所接受。生产实践中,步入老龄期的梨园更新复壮已经成为现代梨园经营面临的新课题。为此,笔者结合在费县薛庄镇开展的老龄梨园改造工作,提出了目标树型（圆柱形）、合理负载、土壤改良、科学灌溉、行间生草、树盘覆盖等系列技术措施,实现了老龄梨园的持续优质、稳产、丰产。 相似文献
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通过对福建省德化县早熟砂梨“黄叶病株”及“正常植株”叶片及土壤的营养诊断分析：黄叶病株叶片平均含镁量0.131%,极显著低于正常植株0.328%;黄叶症较重的果园土壤交换态镁含量低12.6～24.5㎎/㎏及土壤酸性强pH3.6～4.5,诊断结论砂梨叶片黄化现象为镁素缺乏所致。矫治试验效果,叶面喷施1%硝酸镁3次,可以叶色转绿;12月份土壤基施钙镁磷肥株1.3 kg,翌年5月份后有明显矫治效果。 相似文献
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Jerry D. Volesky Walter H. Schacht Ann E. Koehler Erin Blankenship Patrick E. Reece 《Strength and Conditioning Journal》2011,64(5):506-513
Root growth is important to the competitive ability of plants, and understanding how herbage defoliation affects root growth has implications for development of management strategies. Objectives were to determine the effects of defoliation intensity and frequency on root characteristics and herbage production of slender wheatgrass (Elymus trachycaulus [Link.] Shinners), Nebraska sedge (Carex nebrascensis C. Dewey), and “Steadfast” birdsfoot trefoil (Lotus corniculatus L.). Plants of each species were transplanted into containers that had been placed in the ground at wet meadow field sites the prior year. There were eight replications of a control and five defoliation treatments, which were combinations of different frequencies (two or five times) and intensities (light or heavy) and haying. Treatments were applied for a single growing season, and aboveground biomass was collected. Containers were extracted in October, and plant crowns, rhizomes, and roots were separated from the soil. Defoliation treatment did not affect total root weight, length, and surface area of Nebraska sedge or birdsfoot trefoil (P>0.10). Slender wheatgrass total root weight was less when defoliated five times (4.46 g·container?1) than when defoliated twice (6.62 g·container?1) during the growing season. More frequent defoliation of slender wheatgrass also reduced length (20%) and surface area (21%) compared to less frequent defoliation. However, defoliation frequency did not affect aboveground biomass. Defoliation intensity did not affect aboveground production or root characteristics of the three species. Abundant soil moisture in meadows likely buffers negative effects of defoliation. For all species, two defoliation events (e.g., haying followed by grazing) does not appear to negatively affect root growth and herbage production. 相似文献
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介绍了台湾甜脆桃3种主要蛀果害虫桃蛀螟、梨小食心虫、桔小实蝇的生物学特性及危害特点,并提出了综合治理措施,为桃果的安全生产提供科学的参考依据。 相似文献
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近年来,梨木虱在湖北省各梨产区大面积发生,危害梨树芽、叶片、嫩梢和果实,严重影响了梨树的产量及果品质量。本文报道了梨木虱危害症状、梨木虱卵、幼虫、成虫的形态特征,系统研究了武汉地区梨木虱成虫种群和幼虫种群动态变化。结果表明：梨木虱在武汉地区1年发生5代,越冬代羽化高峰期为3月29日,第一代梨木虱羽化高峰期为5月7日,第二代梨木虱羽化高峰在5月28日,第三代梨木虱羽化高峰期为7月9日,第四代梨木虱羽化高峰期为9月4日,第五代梨木虱羽化高峰期为10月19日;第1代、第2代和第3代幼虫危害梨树叶片,而第4代和第5代不危害梨树叶片,而是取食梨园中的幼嫩的杂草。本研究为梨木虱的测报技术和综合防治技术提供了理论依据。 相似文献
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摘要：为探明不同梨树品种对梨瘿蚊的抗性,为梨树抗性品种选育和梨瘿蚊（Dasineura pyri Bouche）的防治提供理论参考。以国家果树种质武昌砂梨圃内的30个砂梨品种为材料,通过人工接种梨瘿蚊的方式,对30个砂梨品种接种梨瘿蚊后的植株受害率和叶片受害率进行了调查,并依据一定的标准计算得到综合受害率,从而对其抗虫性进行了评价,筛选出了金黛梨、早生黄金梨和华山梨等3个对梨瘿蚊的抗性较强的砂梨品种。这可为今后开展梨树抗梨瘿蚊品种选育提供重要材料。 相似文献
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B. R. Roberts 《African Journal of Range and Forage Science》2013,30(1):157-162
The paper evaluates those functions of the grazing‐animal/pasture complex which are influenced by management. The contribution of pasturage to animal production is determined primarily by environment and secondarily by defoliation. In pasture quality evaluation, those approaches which employ both digestibility and intake as basic criteria are generally closely related to animal response. In equating grassland production with animal requirements the determinants of output per animal and output per area must be considered in the perspective of the production system as a whole. The essential influence of grazing method on carrying capacity is stressed and it is suggested that grazing management of natural pasture be based on (i) a knowledge of the contribution of individual species to animal production, (ii) defoliation practice which encourages the most nutritious species and (iii) the introduction of improved pasture species. 相似文献