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31.
贵州省退耕还林工程社会经济效益阶段评价研究 总被引:2,自引:0,他引:2
通过对水城、黎平、望谟、关岭、麻江、黔西、龙里、习水、开阳、铜仁10个退耕还林工程综合效益监测重点县107个固定样地户主共91户退耕农户进行连续4年的跟踪调查,同时结合10个县面上统计数的分析及其典型县204户退耕农户的典型调查,对监测区退耕还林的经济、社会效益进行了评价:退耕还林工程区环境效益经济值明显提高,水土流失得到有效控制;工程区退耕农户收入增加,粮食总产量稳定;退耕还林促进了农村劳动力的转移。 相似文献
32.
H.‐Q. Mou X. Xu R.‐R. Wang Q. Tian Y. Wei S.‐F. Zhu X.‐L. Liao W.‐J. Zhao 《Forest Pathology》2014,44(1):56-61
This article reports Salix tetradenia Hand.‐Mazz as a new host of Candidatus phytoplasma and demonstrates its association with witches' broom disease on S. tetradenia plants. Plants exhibited typical visual symptoms of phytoplasma with virescence, abnormality of flowers and witches' broom, and phytoplasma bodies were observed by transmission electron microscopy. Products of 1.2 kb were amplified by nested PCR using phytoplasma universal primer pairs R16F2n/R16R2, but no amplification products were obtained from symptomless plants. The sequence analysis of three 16S rDNA isolates showed 99.84%, 99.68% and 99.76% identify, respectively, with the homologous gene (nc_005303) of member of ‘Candidatus phytoplasma asteris’ (16SrI) group. Phylogenetic and virtual computer‐simulated restriction fragment length polymorphism analysis of the 16S rRNA, tuf and rp gene sequences confirmed that this phytoplasma clustered in the 16SrI‐B subgroup. These results indicated that the diseased S. tetradenia plants were infected by a phytoplasma of the 16SrI group. This is the first report on the occurrence of phytoplasma disease on S. tetradenia worldwide. 相似文献
33.
A mixture neural methodology for computing rice consumptive water requirements in Fada N’Gourma Region, Eastern Burkina Faso 总被引:1,自引:1,他引:1
Seydou Traore Yu-Min Wang Chun-E. Kan Tienfuan Kerh Jan Mou Leu 《Paddy and Water Environment》2010,8(2):165-173
Crop consumptive water requirement (Crop-ET) is a key variable for developing management plans to optimize the efficiency
of water use for crop production particularly in semiarid zone. In Burkina Faso, the unfavorable climatic conditions characterized
by the low and unevenly distribution of rainfall have pushed water resources management to the forefront of the crop production
issue. Crop-ET is extremely required in rainwater effective management for mitigating the impact of water deficit on the crops.
Basically, Crop-ET determination involves reference evapotranspiration (ETo) and crop coefficient (Kc) which required complete
climatic data and specific site crop information, respectively. ETo estimation with the recommended FAO56 Penman–Monteith
(PM) equation is limited in Burkina Faso due to the numerous meteorological data required which are not always available in
many production sites. In such circumstances, research to compute directly Crop-ET as an alternative to the two-step approach
of calculating ETo and determining site specific Kc, seems desirable. Therefore, this study aims to evaluate the performance
of a mixture principal component analysis neural network (PCANN) model for computing rice Crop-ET directly from temperatures
data in Fada N’Gourma region located in Eastern Burkina Faso, Africa. From the statistical results, rice Crop-ET can be successfully
computed by using PCANN methodology, when only temperatures data are available in this African semiarid environment. Thus,
in poor data situation, Crop-ET direct computation can be rapidly addressed through PCANN model for agricultural water management
in African semiarid regions. 相似文献
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7个籼型水稻细胞质雄性不育系异交性能的研究 总被引:3,自引:1,他引:3
以7个籼型水稻细胞质雄性不育系D62A、D63A、D64A、D23A、G46A、金23A珍汕97A为材料,视珍汕97A为对照,在海南对它们的异交性能进行了研究.结果表明:7个细胞质雄性不育系的颖花开花率从高到低依次为D23A、D63A、D62A、D64A、珍汕97A、金23A、G46A;D62A等6个细胞质雄性不育系的柱头外露率均高于对照珍汕97A;除G46A、金23A外,其余4个的午前花率均比对照珍汕97A高;D62A、D63A、D64A等3个细胞质雄性不育系的平均张颖时间均比对照珍汕97A长,其余三个短于对照珍汕97A.柱头生活力系数大小依次是:对照珍汕97A、D62A、G46A、D63A、D23A、D64A、金23A.异交结实率从高到低的顺序是D62A、D63A、D23A、金23A、D64A、G46A、珍汕97A. 相似文献
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果脯生产过程中进行硫处理,能改善成品的色泽,防止褐变。本试验结果表明:果脯经硫处理,成品和糖液中SO_2残留量受亚硫酸盐使用浓度、使用方法、处理时间、原料种类及制作工艺等诸因素的影响。采用0.2%亚酸酸氢钠溶液浸泡果坯8h,或1%亚硫酸氢钠溶液浸泡果坯2h的硫处理方法,可使果脯中SO_2残留量保持在国家标准规定的允许范围内,并对保持和改善果脯色泽,提高产品质量有较好的效果。 相似文献