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<正>为准确预报晚稻主要病虫发生趋势,及早部署晚稻病虫防治指导工作,江西省植保植检局于8月9~10日在南昌市召开了全省晚稻主要病虫发生趋势分析会商会议。会议总结交流了各地早稻及当前中稻主要病虫发生特点及防治情况,对晚稻主要病虫发生趋势进行了分析会商,并就晚稻病虫害测报防治工作进行了安排部署。 相似文献
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砂壤土栽桑区根结线虫病的发生与防治技术 总被引:2,自引:0,他引:2
桑根结线虫病,又桑根瘤线虫病,是桑树检疫的主要病种,砂土、砂壤土上栽桑发病较重。坡耕地、河滩地实施植桑育林,是退耕还林工程中发展经济生态林建设的举措之一,但蚕桑生产区和新发展区的荒坡、荒滩以及坡耕地,相当一部分为含有机质的砂土或砂壤土,其中一些新栽桑园及苗圃根结 相似文献
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玉米是山西主要粮食作物,常年种植2000万亩以上。每年都因病虫危害,给玉米生产造成程度不同的损失。现针对大同地区的玉米主要病虫谈谈其发生特点与防治措施。 相似文献
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<正> 蜗牛是春秋蔬菜上的重要害虫,发生多,为害重,最为常见的是同型巴蜗牛,这种蜗牛食性杂,能取食多种蔬菜作物,既取食新鲜的植物,又能取食植物残体,如腐烂的菜叶、菜根、未腐熟的有机肥等。近年来,蜗牛在蔬菜上发生普遍,大豆受害后,被害荚脱落,叶片成网状破碎,结荚率低、粒重轻,减产40%~50%,豌豆受害后,叶片破碎,缺苗断垄;蔬菜受害后,叶片严重受损,并留下污痕,对蔬菜产量、品质和经济效益均具有严重的影响。为了摸清蜗牛的发生特点、为害习性及其防治方法,2000~2002年我们对此进行了系统 相似文献
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通过近2年的调查观察,斜纹夜蛾在永安市一年发生6代,4月下旬始见,8月中旬至9月下旬为害最重。发生重的原因主要有:寄主面积扩大,气候条件适宜及常年使用广谱性杀虫剂。综合防治的总体思路是加强测报,应用性诱剂、灯光诱杀、人工捕捉为辅助手段,狠抓化学防治为重点的综合防治措施。 相似文献
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2010年我国大蒜价格与出口情况及2011年形势展望 总被引:1,自引:1,他引:0
回顾了2010年我国大蒜的销售与出口情况,分析了2010年影响大蒜价格走高的因素及2011年大蒜的行情走势,阐述了应对大蒜产业发展挑战的措施与途径. 相似文献
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杭州市典型茶园土壤与茶叶中重金属的积累与来源分析 总被引:7,自引:3,他引:4
为了解杭州市茶园土壤与茶叶中重金属的污染状况及其重金属的可能污染来源,选择杭州市典型茶园20个,按区位与施肥的不同分为城郊-化肥、城郊-有机肥、山区-化肥和山区有机肥等4种类型,采集了0~15、45~60 cm分层土样及茶树新叶和老叶样品,分析土样和茶叶样品中Pb、Zn、Cu、Cd、Hg、Cr和Co等重金属含量。结果表明,研究土壤Pb、Zn、Cu、Cd、Hg、Cr和Co污染程度较轻,其含量均低于土壤环境质量二级标准。除老叶样中Pb有25%样品超标外,新叶及老叶的其他重金属元素都在限值以下。城郊区茶园土壤的Pb、Cd和Hg含量普遍高于山区茶园。施用化肥的茶园土壤Cd略高于施用有机肥的茶园,施有机肥的茶园土壤Hg略高于施用化肥的茶园。施用有机肥的茶园土壤Zn和Cu明显高于施化肥的茶园。施用有机肥可轻微提高茶园土壤中Cr的积累;土壤中Co的积累受人为影响较小。研究认为,研究区茶园土壤中重金属Pb、Cd和Hg的积累主要与大气沉降有关,而Zn和Cu的积累主要与有机肥料的施用有关。 相似文献
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山西运城小麦和玉米苗期地下害虫调查与防控技术研究 总被引:4,自引:3,他引:1
为了解山西运城地下害虫对主要粮食作物小麦和玉米的危害并有效控制,调查了2011年山西南部运城市小麦和玉米的地下害虫发生情况,同时研究植物源农药苦参碱及常用的化学制剂吡虫啉和氟虫腈3种药剂拌种对小麦和玉米种子的出苗率、被害株率、防虫效果以及保苗效果的影响进行统计分析,并对拌种后幼苗的株高、根长及相关的抗氧化酶SOD、POD活性及膜脂过氧化产物MDA进行测定。结果表明,小麦和玉米的苗期地下害虫主要有金针虫、地老虎和蛴螬3种,害虫种类及为害程度因地块变化较为明显;苦参碱对小麦和玉米的种子萌发有一定促进作用,但效果不显著,而对地下害虫的防效和保苗效果相对低于吡虫啉和氟虫腈;幼苗的抗氧化酶SOD和POD活性相对提高,抗性增强,且植物源农药对环境友好,可以在农业生产中推广。 相似文献
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Acidity and sweetness in apple and pear 总被引:2,自引:0,他引:2
Summary Sweetness and acidity in apple and pear inherit independently and can be organoleptically evaluated separately, but less accurately in pear than in apple. For breeding purposes an analysis of fruits for acidity and sweetness with pH indicator paper and a hand refractometer is to be prefered to the organoleptic method.In apple, the acidity-decreasing with time-of the unripe fruit was already strongly indicative of that of the eating-ripe fruit; sugar-increasing with time-not before the fruit was picking ripe. Sugar content in apple and pear, and the pH in pear, appeared to be normally distributed; the pH in apple showed a segregation into an acid and a low-acid group, which occurred in both the unripe and ripe stage. The segregation ratio between these groups was found to be highly variable. On the whole, the mean acidity and sugar content of apple and pear progenies is significantly determined by that of the parents. Most of the observations made did not support the theory that low acidity in apple is determined by one recessive gene. The relationship between the pH of leaf juice and fruit juice in apple may offer a possibility for pre-selection. 相似文献
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Temperature-Related Changes in Chlorophyll Fluorescence and Contents of Chlorophyll and Carotenoids in Andean and European Potato Clones 总被引:4,自引:0,他引:4
Low-temperature adapted Andean potato clones and low-temperature sensitive European clones cultivated at 20/10°C were compared during stress occuring as the result of low-temperature treatments. The stress response of leaf tissue was assessed by measuring the decrease in chlorophyll fluorescence (Fv/Fm) in detached leaves during a period of six days. After temperature stress combined with light Fv/Fm decreased only slightly in the Andean clones, but was markedly lower than the initial values in the European clones, However, after a 2°C treatment in darkness no difference between clones of different origins was detected. In general, chlorophyll and carotenoid contents of the Andean clones were higher than those of the European clones. They were markedly lower in all clones in treatments where low temperature was combined with light, than at 20/10°C and at 2°C in the dark. The contents of carotenoids and total chlorophylls decreased more in the European than in the Andean clones when leaves were transferred to a higher light intensity and then the lowest temperature used was combined with light. Thus carotenoids and chlorophylls in the Europeans clones were more sensitive to photo-oxidation at low temperatures than in the Andean clones. The changes in chlorophyll fluorescence in illuminated, detached leaves induced by a decrease in temperature were found to correlate with the low temperature performance of the genotypes. The correlation between low temperature performance and photosynthetic activity was highly significant and could be used by plant breeders to identify plants that perform well at low temperatures. 相似文献
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Summary Germination of pollen grains and growth of pollen tubes were studied to determine the cause of barreness in crosses among annual Cicer species. In vivo and in vitro time-course studies and fluorescent microscopy revealed no pollination incompatibility among the selfs, crosses and reciprocals of C. arietinum L., C. reticulatum
Lad. and C. cuneatum
Rich. In general, Cicer pollen grains germinated and grew on styles of Cicer species. Pollen tube growth was characterized by irregularly spaced and intermittent callose deposits. Failure of seed formation in interspecific pollinations may be attributed to the slowness of pollen tube growth or collapse of fertilized ovules. In addition to these causes, shortness of stamens and sparsity of pollen grains were responsible for flower drop in natural selfs. Although the number of pollen tubes entering the micropyle in interspecific pollinations was low, it may be possible to grow the fertilized ovules on an artificial medium to obtain F1 plants. 相似文献
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J. Gopal 《Euphytica》2001,118(2):145-151
Relative behaviour of genetic parameters and character associations for in vitro and in vivo systems was studied by evaluating 22 potato genotypes for seven morpho-agronomic characters under six in vitro and four in vivo conditions. There was considerable similarity between in vitro and in vivo systems with regard to pattern of coefficient of variation (both phenotypic and genotypic), heritability (broad sense), genetic
advance (as% of mean) and correlation coefficients (both phenotypic and genotypic) between characters. The magnitude of various
genetic parameters was higher under in vitro than in vivo conditions, particularly for tuber yield and its components. Treatment-to-treatment variation in genetic parameters and character
associations was higher under in vivo than in vitro conditions. In vitro selection for agronomic characters in potato may be possible.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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农药的使用对农作物,尤其是蔬菜和水果的害虫防治起着重要的作用,但不合理的农药使用会带来农药残留超标、环境污染等问题。中国幅员辽阔,各地蔬果中农药残留的情况有所不同。因此,本研究分析了近10年中国四大经济区域蔬果中的农药残留现状以及在不同蔬果类型、购入来源和季节情况下的农残差异,探讨了去除蔬果中农药残留的家庭加工方法,并在此基础上对农药的科学合理使用和蔬果中农残的有效去除提出相关建议。 相似文献