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81.
We investigated changes in radiocesium concentrations in a Japanese chestnut (Castanea crenata Sieold &; Zucc.) orchard in Ibaraki prefecture for 3 years after the Tokyo Electric Power Company’s Fukushima Daiichi nuclear power plant accident in March 2011. The radiocesium concentrations in the aboveground organs of Japanese chestnut trees were almost the same, while the concentration in the roots was the lowest among all the organs investigated. The concentration of radiocesium decreased exponentially for 3 years in nuts, leaves and current shoots. The radiocesium concentrations in soils were higher in the surface layer, and the trend of an annual decrease in radiocesium in the soils was similar to that of the natural decay of radiocesium. The transfer factor of radiocesium from soils to nuts of Japanese chestnut decreased annually. These results suggest that radiocesium adhered directly to the aboveground organs of Japanese chestnut trees in March 2011, and that the accumulation of radiocesium in nuts is mainly due to radiocesium transfer from the branches and trunk to nuts several years after the nuclear power plant accident.  相似文献   
82.
板栗的防腐贮藏   总被引:6,自引:0,他引:6  
板粟收获后用一定浓度的化学防腐剂处理,或用一定剂量的Coγ─射线辐射处理,可以明显地抑制板栗的霉烂,降低贮藏损失。  相似文献   
83.
江西板栗疫病发生规律的研究   总被引:5,自引:1,他引:4  
  相似文献   
84.
对密植栗园采用不同的修剪措施,可有效地控制树冠过早郁闭,增加有效结果枝量,使产量稳定在230-240kg/666.7m^2。  相似文献   
85.
板栗树体水分与土壤水分动态变化的相关分析   总被引:5,自引:0,他引:5  
通过观测板栗的根、枝、叶及栗园土壤水分含量的动态变化发现:根、枝、叶组织水分含量的变化随着栗园土壤含水量的变化而变化;30cm土层为板栗根系的主要吸水层;北方山地栗园,春季每15-20天需要进行一次灌水,以满足板栗树体生长发育对水分的需求。  相似文献   
86.
Residues of the insect growth regulator diflubenzuron were quantified on horse chestnut (Aesculus hippocastanum L.) leaves treated with a diflubenzuron 480 g litre?1 SC, Dimilin. To analyse the samples, an analytical procedure was developed involving a simple extraction step followed by high‐performance liquid chromatography on an octadecyl‐modified silica column with methanol + 0.01 M ammonium acetate mobile phase. The results showed diflubenzuron to be highly stable on horse chestnut leaves; more than 4 months (127 days) after application, 38% (on average) of the insecticide still remained on/in the leaves. The data confirmed biological observations showing diflubenzuron's long‐term efficacy against the horse chestnut leafminer, Cameraria ohridella Deschka & Dimi?, which is the most important pest of the horse chestnut in Europe. The hypothesis of possible penetration of diflubenzuron into the leaf mass is explored and discussed. Copyright © 2006 Society of Chemical Industry  相似文献   
87.
在前期进行低丘栗园板栗病虫害综合防治技术开发研究基础上,2002年将研制的“板栗防病虫增产”高效新配方药剂在仪征低丘栗园进行大面积示范推广,取得显著效果。推广示范区平均病虫减退率达78.74%,比对照增加57%;单位面积产量比对照增加75.98%-331.3%。平均增产1.6倍,推广示范区单位面积平均产值达10208.25元/hm^2。比对照增加6021.45元/hm^2;投入产出比达1:(7.35-46.91),平均投入产出比达1:20.1。对提高低丘开发效益,促进林农增收产生了重要作用。  相似文献   
88.
Forty eight isolates of Phytophthora cinnamomi from various host plants in France (35 isolates) and in other countries were tested for pathogenicity. Seedlings of chestnut, northern red oak, pine and eucalyptus were infected by soil contamination. Taproots, stems and bark strips of plants of chestnut and different oak species were inoculated with mycelium agar disks. Results of the different experiments were in good agreement. All isolates appeared pathogenic to all the different test species but with variable levels of virulence. Isolates with consistent low or high level of virulence, which could be used as standards in further studies, were identified. Interaction between P. cinnamomi isolates and host plant species was significant in terms of lesion lengths. These interactions could not be related to host from which P. cinnamomi was isolated. Consistent with this, in Quercus rubra, the isolate-provenance interaction was not significant. This feature is encouraging for provenance screening for resistance to P. cinnamomi in this species. The variation in virulence was not related to other isolate characteristics (mating type, electrophoretic type, age).  相似文献   
89.
麦类作物对禾谷胞囊线虫的抗病性   总被引:8,自引:0,他引:8       下载免费PDF全文
于1995-1997年从广州南海市采集荸荠枯萎标本,经分离,纯化,鉴定和致病性测定,证实其病原为尖孢镰刀菌的荸荠专化型。寄主范围测定结果表明,被接种的16种植物中仅有荸荠发病。该病菌分生孢子萌发的温度范围为8-36℃。最适温度28-30℃。菌丝生长的温度范围为8-34℃,最适温度26-28℃。  相似文献   
90.
为探讨板栗脆片增香的工艺技术,将生板栗及蒸、煮后的板栗分别切成厚度1 mm、2 mm、3 mm的板栗片,将板栗片在5个温度(160℃、180℃、200℃、220℃、230℃)进行不同时间的烘烤,再通过感官评定,研究板栗脆片的增香增色效果。结果表明:3种不同处理方式下,煮后烘烤的板栗片的增香增色效果最好,蒸后烘烤的板栗片次之,生板栗片烘烤后的效果最差,且煮后3 mm厚度板栗片在220℃、230℃烘烤25~30 min能达到最佳增香增色的效果。  相似文献   
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