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81.
ABSTRACT

Sucker production of important clones belonging to different ploidy levels and genomic groups were assessed in three different planting seasons at Kerala Agricultural University, Thrissur, India. The study revealed that morphological characters such as plant height, collar girth, and total number of leaves recorded very strong, significant, and positive correlation with sucker production characters but negative correlation was observed with average leaf production interval and bunch weight. The number of dead suckers was found to be positively correlated with plant height, collar girth, “D” leaf area, bunch weight, and average leaf production interval. In a cluster analysis, six banana varieties that were planted in different three seasons (18 entries) and their pooled data (6 entries) were grouped into four distinct clusters each. In factor/principle component analysis, the first three major factors/principle components amounted to a total of 85.9% of the variability. The communality values of the factor analysis revealed that collar girth was the major relative contributory trait for deciding the sucker yield and production in banana.

Abbreviations: EVS: Early vegetative stage; AVS: Active vegetative stage; FBI: Flower bud initiation; FBD: Flower bud differentiation; PCA: Principle component analysis; FA: Factor analysis  相似文献   
82.
Although conservation attention has generally focused on large forest tracts, there is increasing evidence that smaller forest patches are important for both conservation and rural development. A study of forest patch conservation in a rural Costa Rican community found that, although forest patch conservation was influenced by landholding size, material factors did not account for all the variation in forest patches conservation behavior or conservation orientations of farmers. A qualitative interpretive approach, using semi-structured interviews, found that environmental values were influenced by at least three factors. First, colonist farmers with direct experience with environmental degradation in other regions of Costa Rica were more likely to be concerned about environmental degradation. Second, childhood exposure to conservation played an important role in influencing conservation orientations. Third, the environment was frequently discussed in relation to the moral and social values present in religious doctrines. The study also found general support for forest conservation laws, and a clear indication that interest in forest conservation has grown in recent years. The study highlights the importance of environmental values, in conjunction with material factors, in influencing forest conservation in rural communities.  相似文献   
83.
Early ventures into site-specific management involved fertilizer management decisions based on soil chemical properties characterized by some form of grid sampling. This is both labor and capital intensive and practitioners quickly began investigating other methods to get a measure of spatial variability. Aerial photographs, which were mainly used to evaluate and assess crop status, allow for the collection of whole-field data at relatively low cost. Our objective is to determine what relationships exist between aerial spectral data and intensive grid soil test results and whether this information can be used to improve future soil sampling strategies. Soil-test organic matter (OM) and Bray-1 P concentrations were measured on soil samples taken using an alternating 12.2- by 24.4-m grid in late March 1994 from a quarter section under center pivot irrigation. Spectral data were collected in the spring of 1996 prior to planting using a multispectral network of digital cameras. Correlations of brightness values from the blue, green, and NIR bands with both OM and Bray-1 P were significant, but relatively low. Normality tests revealed that brightness values for the spectral data sets were generally evenly distributed while those of the soil test OM and Bray-1 P were positively skewed. Many of the very high soil-test data values were due to past management. When those values were removed from the database, greater correlations between spectral data and soil test data were obtained. These results substantiated that aerial imagery can be used to improve sampling strategies, but it must be used in conjunction with existing knowledge and past management histories.  相似文献   
84.
为探索玉田县适生植物资源,进行实地调查,立足于植物资源的生态价值,运用生态服务价值评价与当量因子法研究不同区域的适生植物。结果表明,玉田县北部褐土丘陵地带应多种植榆树、黄栌、油松等植物;中部平原草甸地带应种植紫穗槐、栾树与侧柏等,植物与园林观赏植物交叉种植;南部脱沼泽化潮土区域应多种植油松、栾树、臭椿等植物,补充种植牡荆等观赏植物。  相似文献   
85.
生态服务价值是反映一个区域生态环境状况的优劣和整体生态效益大小的重要概念与指标。根据研究区土地利用特点和生态系统类型特征,选取适合研究区的植被净初级生产力、植被覆盖度等生态参数,利用Landsat TM遥感影像、地面观测、气象数据、统计资料等数据,建立了基于遥感定量测算的生态服务价值评估指标与评估模型,对研究区单项和单位面积生态服务价值进行了定量计算。结果表明:研究区在2000-2010年10年间,随着不同土地利用类型之间的相互转换,研究区生态服务价值总量呈逐渐减少的趋势。其中,耕地生态服务价值减少了11.92%,湿地减少了11.75%,总价值减少了5.74%,虽然林地、水域和滩涂的生态服务价值有一定程度的增加,但是未能改变研究区总体生态服务价值不断减少的趋势。在此基础上分析了研究区生态服务价值时空变化规律,揭示了其土地利用与生态服务价值变化之间的内在关系。  相似文献   
86.
以从连续流搅拌槽式反应器(CSTR)内的活性污泥中分离出的高效厌氧产氢菌Biohydrogenbacterium R3 sp.nov.为发酵产氢微生物,糖蜜废水为发酵底物,试验分析了连续流发酵法R3菌株的产氢效能.结果表明:在温度36℃、水力停留时间6h、进水COD在2 600~4 440 mg/L范围内变化,CSTR...  相似文献   
87.
家训文化是中华民族优秀的传统文化,其与社会、个人以及社会主义核心价值观的主流意识形态有着紧密的关联。高校在培育社会主义核心价值观的工作中,要做到细致、落实、落小,离不开优秀传统家训文化的熏陶。讨论了优秀传统家训契合社会主义核心价值观的价值诉求以及优秀传统家训文化在当前时代的价值,提出了优秀传统家训文化在高校培育社会主义核心价值观中的具体路径。  相似文献   
88.
黑龙江八一农垦大学是一所具有鲜明农垦现代化大农业教育和科研特色,以农为主、多学科协调发展的农业大学。图书馆品牌建设立足农垦大学,论述了大学图书馆品牌建设的内涵和意义,分析了影响和制约大学图书馆品牌建设的主要因素,提出了大学图书馆品牌建设的方略。  相似文献   
89.
对高等农林院校人文素质教育存在的问题和成因进行分析,阐述了开展人文素质教育的必要性,并提出了加强高等农林院校人文素质教育的途径:(1)树立现代人才观念,丰富大学人文精神教育的内涵;(2)加强人文学科建设和教学管理;(3)改革人文知识教育的考核方式,完善评价体系;(4)充分发挥大学语文在人文素质教育中的作用;(5)努力营造以社会主义的核心价值观为中心的校园文化。  相似文献   
90.
为了评定不同生育期虉草的营养价值,分析体外产气法和CNCPS法两种营养评价方法的相关性。采用体外产气法测定抽穗期、开花期、灌浆期、乳熟期4个生育期虉草的体外发酵产气量、发酵参数(a、b、c)、DM消化率、NDF和ADF降解率,用康奈尔净碳水化合物和蛋白质体系(cornell net carbohydrate and protein system,CNCPS)分析方法测定相应组分,评价其营养价值,并比较研究两种方法评价结果的相关性。结果表明,体外发酵至72 h结束,累计总产气量和产气参数a以开花期最高(122.68 和4.46 mL),显著高于各组(P<0.05),且从抽穗期、灌浆期、乳熟期有降低的趋势;抽穗期和开花期的DM消化率、NDF和ADF降解率分别显著高于灌浆期和乳熟期(P<0.05)。随着虉草生育期的延长,CP和SOLP呈递减趋势,即抽穗期和开花期显著高于灌浆期和乳熟期(P<0.05);NDF、ADF和ADL呈递增趋势,但NDFIP、ADFIP呈递减趋势。灌浆期和乳熟期的CHO含量显著高于抽穗期和开花期(P<0.05),而CA和CNSC含量则相反,且CC含量同样以灌浆期与乳熟期较高;蛋白质组分中,PA与CA及CC与PC组分呈现同样的趋势。虉草CNSC、CA、CB1、CB2、PA、PB3组分含量与不同时间点产气量呈显著或极显著的相关性(P<0.05或P<0.01)。因此,开花期虉草营养价值最高,其次为抽穗期、灌浆期和乳熟期,产气法和CNCPS评价牧草具有相关性,用体外产气量估测牧草CNCPS组分是可行的。  相似文献   
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