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如何利用生命表资料进行烟青虫发生趋势预测 总被引:3,自引:0,他引:3
所谓中期预测,其预测期限一般为20d到一个季度,常在一个月以上,通常是预测下一个世代的发生情况。所谓长期预测,其预测期限常在一个季度以上,通常是根据越冬后或年初某种害虫的越冬有效虫口基数及气象预报资料作出,于年初展望其全年发生动态和灾害程度。所谓生命表,通俗地说,就是“一群同龄个体的生死流水账”,即是通过实验或调查,获得每一个特定时间或特定虫期(虫态)开始时的生存数(即lx项),相应地可得到死亡数(即qx项),并查明死亡原因,测出雌成虫的平均产卵数,将这些数据组建成表格形式。通过对一种昆虫多个世… 相似文献
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甘蔗二点螟(ChiloinfuscafellusSue-llen)以幼虫越冬。低龄幼虫在种蔗和盖膜宿根蔗内,8℃以上温度即可取食为害,可成为有效虫源。进入滞育的龄期为5龄,一旦滞育,幼虫则不能老熟,但仍可取食和脱皮。老熟幼虫可以休眠方式越冬。预蛹期前有3~5天的后补营养期,蛹历期6~18天。年发生代数l~4代。甘蔗二点螟在湖南的发生特点@黄河清 相似文献
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1997年7月用1.8%虫螨克乳油进行了防治烟青虫(HeliothisasultaQuenee)田间试验和室内试验,并与5%卡死克乳油、BT粉剂、40%SN-851乳油进行对比。试验结果表明,虫螨克3000倍药后3天防效为93.6%,5天防效为94.2%,7~15天防效达100%。药效期达15天以上,对2、3龄烟青虫幼虫有较好的防效,且对大龄幼虫的灭杀作用更好,同时表明该药剂具有较好的安全性,对天敌杀伤力低,与BT粉剂相比防效相当,优于当地常用农药SN-851,可以作为一种新型药剂进行推广,用于防治烟青虫。建议使用量为3000倍即667m2用20ml为宜。 相似文献
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5%特丁磷颗粒剂(地虫灵)防治甘蔗地下害虫试验研究 总被引:3,自引:0,他引:3
本文报道了1993年和1996年用5%特丁磷颗粒剂(地虫灵)防治甘蔗地下害虫的试验结果,每公顷用特丁磷ai1.80~2.25kg防治黑色蔗龟效果为80.98%~84.425,防治二点褐鳃金龟(蛴螬)效果为85.04%~98.60%,本文还就5%特丁磷酸剂的应用前景及使用方法进行了阐述。 相似文献
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甘蔗二点螟是甘蔗的主要害虫,在湘北蔗区,每年发生3~4代,以第一代发生为害最重,如防治不好,每年造成的枯心率在5~20%,最高丘块可达50%以上。二点螟在甘蔗上的发生为害比较复杂和特殊。一是发生盛期长,盛期内高峰多。这是由于二点螟主要在蔗克、种蔗茎内以幼虫越冬,甘蔗播种后,上部蔗碴、上面蔗克及地膜覆盖的种茎内的越冬幼虫由于温度较高发育进度快Z而土壤下面的蔗朝、下部蔗碴、套作甘蔗茎内的越冬幼虫由于温度低,发育进度慢。在本地,越冬代成虫发生盛期一般在4月25日至5月15日,长达20多天,最早在4月1… 相似文献
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湖南烟区斜纹夜蛾(Spodoptera litura)的发生规律及预测方法 总被引:2,自引:0,他引:2
以郴州、宁远等县连续多年田间调查资料为基础,结合当地气象数据,分析了湖南省斜纹夜蛾的发生规律。结果表明,根据有效积温斜纹夜蛾在湖南每年发生4.0~4.5代,理论代数与实际代数相符;湖南斜纹夜蛾每年初始虫源全部为外地虫源;按虫源性质,全年可分为4个不同的发生时段;3月的诱蛾量与4—6月诱蛾量有显著的相关性,预测模型为y=233.54+112.44x4(r=0.815*,n=8);1月平均温度与4—6月诱蛾量也有明显的相关性(达90%可信度),预测模型为y1410350X3(r=0.595,n=9);同步迁飞昆虫小地老虎主迁入期(2—4月)的性诱蛾量与斜纹夜蛾主迁入期(4—6月)也具相关性,均可供发生趋势预测参考。斜纹夜蛾的百株虫量与为害率呈显著相关性。 相似文献
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《Journal of dairy science》1987,70(2):414-417
Design of germplasm comparisons depends on the hypothesis to be tested. Most important hypotheses concern the future environment for production and marketing. 1) Will the best bulls in an exotic breed improve a local breed?; 2) Is it efficient to upgrade a local breed with bulls from a related exotic breed that has a large, effective program of genetic improvement? 3) Is it efficient to replace a local breed with an exotic one? 4) Can continual crossbreeding with an exotic breed be the most efficient improvement program? Proper answers depend on obtaining information on all important inputs and outputs of exotic and local breeds as well as expected future genetic trends in each. Evidence suggests that multiple lactations are necessary to measure adequately lifetime economic merit. It is crucial that experiments give answers that reflect the relative values of local and exotic breeds at the time the experiment is completed rather than the differences that existed at time animals were selected. 相似文献
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甜菜幼苗叶片蔗糖磷酸合成酶的一些特性 总被引:2,自引:0,他引:2
通过实验测定了蔗糖磷酸合成酶(SPS)在甜菜幼苗叶片生长时表现出的一些特性。随着叶片的生长发育,最初没有测出SPS活性,以后其活性逐渐增大,并稳定下来,SPS活性与叶的长度和叶绿素含量的增加存在的依从关系,另外,缺P和缺K时,SPS活性受到抑制作用。 相似文献
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“过程控制”管理是ISO9000质量管理体系的核心思想。运用“过程控制”管理建立葡萄酒企业管理体系,由全面、规范、系统的质量标准体系;完整、全面的监督、检查体系;对关键车间、工序进行现场控制、监督;企业内部质量监督审核等组成。并对成品酒的调配及过滤工艺;灌装前原酒及包装工序质量控制;入库、出库产品质量控制;不合格产品处理等4个具体过程进行控制。(津京) 相似文献
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Christine Kenter Christa M Hoffmann 《Journal of the science of food and agriculture》2006,86(1):62-70
The chemical composition of sugar beet is the most important parameter affecting its processing. Sugar factories require beet with high concentrations of sucrose and low concentrations of melassigenic substances to maximise the amount of extractable sugar. In order to plan the processing campaign, forecasts of root and sugar yield by prediction models are possible but there are no means to predict the technical quality of the beet. In the present study, the seasonal development and physiological relationships of different parameters of sugar beet quality were analysed. In order to estimate possibilities for quality forecasts, the concentrations of beet quality variables in October were correlated with corresponding quality measurements in late summer and to weather variables during the growing season by linear regressions. In 2000 and 2001, 27 field trials were conducted on commercial farm fields in all sugar beet growing areas in Germany. From June to October, sequential samples were taken every 4 weeks and the concentrations of sucrose, potassium, sodium, total soluble nitrogen, α‐amino nitrogen, nitrate, betaine, reducing sugars and marc in the beet were determined. The sucrose concentration increased progressively until the final harvest date in autumn, whereas the concentrations of the melassigenic substances decreased markedly until late summer and remained fairly constant as the season progressed. Marc concentration was the most stable of the parameters analysed. The sucrose concentration was positively correlated with the concentrations of dry matter, betaine and marc, but negatively with nitrate concentration and leaf yield throughout the season. The correlation between the concentrations of sucrose and nitrogenous compounds measured in summer and their final concentrations in autumn was rather weak. However, it was close for potassium, sodium and marc and a satisfactory prediction of their final concentrations was possible by the end of August. Based on weather data, beet quality was not predictable. Therefore, it seems to be difficult to integrate beet quality parameters into prediction models. Copyright © 2005 Society of Chemical Industry 相似文献
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目的 通过对2015-2019年贵阳市食源性疾病监测数据的整理分析,掌握本地区食源性疾病的发病特点和规律.方法 按发病的时间、年龄、职业、发生场所、食品包装方式及地区分布等对监测数据进行统计分析.结果 2015-2019年,贵阳市监测医院共报告食源性疾病病例4335例.6-10月为食源性疾病的高发期,占59.22%(2... 相似文献
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当前全球的能源消耗的速度以及对环境的影响变得日趋重要。制糖是食品工业中主要的耗能大户,制糖生产在许多发展中国家还是能源密集型产业之一,这主要由于技术设施落后造成的。本文从技术层面探讨最近三十年来甜菜制糖工业节能技术的发展。 相似文献