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941.
陆稻优异种质资源筛选与评价 总被引:3,自引:1,他引:2
对16个陆稻种质资源的四大主要性状(植株性状、谷粒类型、产量性状和耐旱性)进行了系统考察、模糊隶属分析和模糊综合评判。评判出其优劣顺序为:德旱1号>巴西陆稻>旱稻277号>旱稻95树村502>吴氏旱稻>旱稻297号>旱稻2号>旱稻9号>旱稻95树村104号>旱稻8号>旱稻95树村9号>旱稻44号>IRAT104>陆稻604>87641>陆稻4号,筛选出5个优异种质资源为:德旱1号,巴西陆稻,旱稻277号,旱稻95树村502,吴氏旱稻 相似文献
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945.
在实验室规模下,以旋转式生物流化床(CB-FSB)为研究对象,研究了初始总氨氮(TAN)、水温及滤料膨胀率3种条件下,海水生物流化床生物过滤功能启动期间TAN和亚硝酸盐氮(NO-2-N)去除及amoA基因数量的变化。结果显示:生物流化床生物过滤功能启动所需时间随着水温的升高而缩短,在水温为15℃、20℃和25℃时,启动所需时间分别为27 d、25 d和23 d;初始TAN质量浓度的升高也会缩短生物流化床生物过滤功能启动所需要的时间,在初始TAN质量浓度为1 mg/L、2 mg/L、4 mg/L时,启动所需时间分别为24 d、22 d和21 d;在膨胀率为100%和150%时,启动所需时间无明显差别,分别为21 d和20 d,明显好于膨胀率为50%时启动所需时间27 d;amoA基因的数量变化与TAN去除率的变化有一定的相关性,并随着初始TAN浓度的升高而增多,在4 mg/L时数量最多,达到2.76×10~7copies/g。 相似文献
946.
The following parameters were measured on seven field plots at 3 sites which had been under organic farming for different periods of time: mineral nitrogen (N min) contents, in situ net nitrogen mineralization (N net), soil microbial biomass carbon (C mic), and nitrogen (N mic) contents, and extractable organic N contents. The measurements were conducted every three weeks from spring 1995/1996 to autumn 1997. The objective was to test whether, under organic farming: 1) temporal fluctuations of Nmic contents over the course of the year are indicative for a source‐and‐sink function for plant‐available N of the soil microbial biomass, and 2) temporal variations in Nmic content can be related with in situ Nnet or plant N uptake. Nmin contents gradually increased after ploughing in autumn until late winter. During intensive plant growth in spring, values rapidly declined. In situ Nnet fluctuated only moderately and reached high values during intensive plant growth (May—July) as well as after soil cultivation in autumn. The Cmic and Nmic contents generally were low in winter, increased in spring and reached maxima in late spring or summer. In spring, the increase in Cmic contents preceded the increase in Nmic contents, resulting in elevated Cmic:Nmic ratios until shooting of winter wheat. This corresponds to an uptake of available soil nitrogen by the plants at the expense of soil micro‐organisms. The subsequent increase in Nmic contents, coinciding with high plant N uptake rates, indicates an enhanced, plant‐induced N mobilization at that time. Possible mobilization mechanisms are discussed. Soil microbial biomass exerted a source‐and‐sink function for extractable organic N on some of the field plots. Estimates of in situ Nnet measurements were neither correlated significantly with soil microbial biomass N, Nmic flux, Nmic turnover, nor with plant N uptake. Lower Nmic turnover rates on 41 years versus 3 years organically managed fields indicate a stabilizing effect of organic farming on soil microflora. 相似文献
947.
Jia Jihong 《保鲜与加工》1998,(1):97-101
This paper studies the duality of the Multiobjective optimization problem involving generalized F-invex functions in Banach space. The constraint qualification and lemma 1 are introduced. The Wolfe type of duality and Mond-Weir type of duality are obtained. Strong and weak duaity theorems and other results are given under weaker F- invexity assumptions. 相似文献
948.
Influence of likelihood function choice for estimating crop model parameters using the generalized likelihood uncertainty estimation method 总被引:3,自引:0,他引:3
Proper estimation of model parameters is required for ensuring accurate model predictions and good model-based decisions. The generalized likelihood uncertainty estimation (GLUE) method is a Bayesian Monte Carlo parameter estimation technique that makes use of a likelihood function to measure the closeness-of-fit of modeled and observed data. Various likelihood functions and methods of combining likelihood values have been used in previous studies. This research was conducted to determine the effects of using previously reported likelihood functions in a GLUE procedure for estimating parameters in a widely-used crop simulation model. A factorial computer experiment was conducted with synthetic measurement data to compare four likelihood functions and three methods of combining likelihood values using the CERES-Maize model of the Decision Support System for Agrotechnology Transfer (DSSAT). The procedure used an arbitrarily-selected parameter set as the known “true parameter set” and the CERES-Maize model to generate true output values. Then synthetic observations of crop variables were randomly generated (four replicates) by using the simulated true output values (dry yield, anthesis date, maturity date, leaf nitrogen concentration, soil nitrate concentration, and soil moisture) and adding a random observation error based on the variances of corresponding field measurements. The environmental conditions were obtained from a sweet corn (Zea mays L.) experiment conducted in 2005 in northern Florida. Results showed that the method of combining likelihood values had a strong influence on parameter estimates. The combination method based on the product of the likelihoods associated with each set of observations reduced the uncertainties in posterior distributions of parameter estimates most significantly. It was also found that the likelihood function based on Gaussian probability density function was the best among those tested. This combination accurately estimated the true parameter values, suggesting that it can be used when estimating CERES-Maize model parameters for real experiments. 相似文献
949.
几种中草药饲料添加剂对黄鳝免疫功能和生长性能的影响 总被引:5,自引:3,他引:2
将300尾13~17g的健康黄鳝(Monopterus albus)随机分为1个对照组和4个试验组,每组3个重复,试验组分别饲喂添加有茯苓、五加皮、黄芪以及这3种中药的混合物的饲料。经30d饲养后,结果表明,茯苓、黄芪及五加皮可使黄鳝血液白细胞的吞噬活性、血清的溶菌酶活性和超氧化物歧化酶(SOD)活性显著提高(P<0.05);同时,五加皮、黄芪、茯苓及这3种中药的混合物均对黄鳝增重有显著促进作用(P<0.05),其中五加皮对黄鳝的增重最为明显。 相似文献
950.
林琳 《农业机械化与电气化》2010,(3):41-42
小麦麸皮作为小麦加工主要副产物,含有丰富的酶系、蛋白质、碳水化合物、维生素及矿物质等,其营养成分的开发利用,具有很高的经济效益和社会效益。分析麸皮中的营养成分及其功能性质,阐述开发利用小麦麸皮的几种途径,为农副产品加工增值提供新的途径。 相似文献