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61.
高产优质杂交稻新品种钱优3301系福建省农业科学院生物技术研究所与浙江省农业科学院作物与核技术利用研究所用钱江1A/闽恢3301联合培育的,2014年通过福建省农作物品种审定。2016年引入闽清县种植,平均产量达9 127.9 kg/hm~2,具有株型适中、群体整齐、综合性状好、稻米品质优等特点。总结了钱优3301在闽清县种植表现及高产栽培技术。 相似文献
62.
通过多个粳型水稻品种与籼型品种的对比栽培试验,分析其生物学特性,表明粳型品种分蘖力弱,有效穗少,但穗粒数多,茎秆粗壮,抗倒。粳型品种高产栽培策略是合理密植,创建最优群体结构,增加有效穗,提高结实率,及时预防稻曲病。 相似文献
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65.
Piet?C.?N.?GroenewaldEmail author Carin?S.?Viljoen 《Journal of Agricultural, Biological & Environmental Statistics》2003,8(1):75-83
This article aims to determine the effect of certain covariates, such as season of kidding, parity, and time of kidding on
the characteristics of the lactation curve of Saanen dairy goats. Characteristics investigated are peak milk yield, time of
peak milk yield, total milk production, persistency, and the relationship between fat and protein in milk composition, as
well as between lactation curves of the same animal in successive years. The analysis is carried out using a hierarchical
Bayesian approach, together with Wood’s model, to model lactation. Posterior distributions of quantities of interest are obtained
by means of the Markov chain Monte Carlo (MCMC) methods. These clearly illustrate the significant effect of especially parity,
but also season and time of kidding on the characteristics of the lactation curve. Total and peak milk yield increase with
increasing parity up to about the third or fourth parity, while peak yield is later for first than for later parities. The
analysis also enables estimation of lactation characteristics of untested animals, prediction of future characteristics and
identification of exceptional animals. 相似文献
66.
Mathias?FosuEmail author Ronald?F.?Kühne Paul?L.?G.?Vlek 《Biology and Fertility of Soils》2003,39(2):117-122
In order to understand the efficiency of residue-N use and to estimate the minimum input required to obtain a reasonable level of crop response, it is important to quantify the fate of the applied organic-N. The recovery of N from 15N-labelled Crotalaria juncea was followed in the soil and the succeeding maize crop. Apparent N recovery (ANR) by maize from unlabelled Crotalaria juncea, Crotalaria retusa, Calopogonium mucunoides, Mucuna pruriens and mineral fertilizer at three locations were also evaluated. The maize crop recovered 4.7% and 7.3% of the 15N-labelled C. juncea-N at 42 days after sowing (DAS) and at final harvest, respectively. The corresponding 15N recovery from the soil was 92.4% and 58.5%. The highest mean ANR of 57.4% was with mineral fertilizer, whereas the mean ANR of 14.3% from C. retusa was the lowest. A large pool substitution and added-N interaction effect was observed when comparing N recovery from the labelled and unlabelled C. juncea. The amount of residue-N accounted for by the isotope dilution method at 42 DAS was 97.1% and at final harvest 65.8%. The large residue-N recovery in the soil organic-N pool explains the residual effect usually observed with organic residue application. 相似文献
67.
Maria?Teresa?Dell'AbateEmail author Anna?Benedetti Alessandra?Trinchera Daniele?Galluzzo 《Biology and Fertility of Soils》2003,37(2):124-129
Carbon and nitrogen mineralisation of leather meal fertilisers were studied in two soils characterised by different respiration activity. Both C and N mineralisation were highest in the most active soil, and when leather meal was added as a powder rather than as 2- to 4- and 4- to 6-mm particles. Fast and slow soluble N pools were determined after extraction with cold water and with hot buffer, respectively. The N remaining after the second extraction with hot buffer was named slow-release N. The percentage of slow-release N rose as the size of the applied leather meal particles increased, whereas fast soluble N was highest in the coarsest (4-6 mm) fertiliser. 相似文献
68.
不同比例尺DEM提取地面坡度的精度研究——以在黄土丘陵沟壑区的试验为例 总被引:53,自引:8,他引:53
以陕北绥德县韭园沟流域为试验样区 ,采用高精度 1∶ 1万 DEM所提取的坡度为准值 ,应用多层面复合分析和比较分析的方法 ,研究该地区 1∶ 5万 DEM提取地面坡度的误差特征与纠正方法。试验结果显示 ,所获得的不同空间尺度下 DEM所提取坡度值的转换图谱 ,可对 1∶ 5万 DEM计算的地面坡度统计值进行有效修正。该成果对于 DEM数据在水土保持领域若干应用标准的制定 ,提供了重要的理论依据与技术路线 相似文献
69.
Effect of bensulfuron-methyl (a sulfonylurea herbicide) on the soil bacterial community of a paddy soil microcosm 总被引:2,自引:0,他引:2
The effect of bensulfuron-methyl (BSM) on a soil microbial community in a model paddy microcosm was studied. Total bacterial numbers in the overlying water and surface soil were monitored for 2 months after the application of BSM at the field rate and a ten-fold field rate. Pentachlorophenol (PCP) was used for comparison. Neither chemical affected the total bacterial numbers remarkably, either in the overlying water or in the surface soil. In contrast, the nitrification potential was significantly suppressed by the BSM application. The bacterial community structure, as evaluated by the denaturing gradient gel electrophoresis (DGGE) of PCR amplification products from bacterial 16S rDNA, was unaffected by the BSM treatments over 8 weeks in the surface soil, compared with the control (no pesticide). In contrast, the surface soil exposed to PCP at a ten-fold field rate showed different patterns from the controls at 4 weeks and 8 weeks after application. The DGGE patterns of the overlying water were much more variable than those of the surface soil in any treatments. Cluster analysis showed that the BSM plots were classified within the same group as the control at 1 week after application and that the BSM and PCP plots from 2 weeks onward after application were grouped differently from the control. Of 22 clones excised from the DGGE gels, 20 clones belonged to the Proteobacteria and two belonged to the Verrucomicrobia. It was considered that the impact of BSM on the overall microbial community (total numbers, community structure of soil) was negligible, although BSM had an impact on some specific functions of the soil microbial community (nitrification) and a part of the community (overlying water). 相似文献
70.
冬播麦区Glu-1和Glu-3位点变异及1B/1R易位与小麦加工品质性状的关系 总被引:22,自引:3,他引:22
贮藏蛋白组成是决定小麦加工品质的重要因素。本文调查了我国冬播麦区251份主栽品种和高代品系的高分子量麦谷蛋白亚基(HMW-GS)、低分子量麦谷蛋白亚基(LMW-GS)和1B/1R易位的分布状况,研究了它们与加工品质性状的关系。结果表明,品质较差的HMW-GS N、7+9、2+12和LMW-GS Glu-A3a与Glu-B3j(1B/1R易位)在冬播麦区分布较广,频率分别为39.4%、45.0%、59.8%、37.1%和44.6%。HMW-GS和LMW-GS等位变异对籽粒蛋白质含量影响较小,对SDS沉降值、和面时间与耐揉性的加性和互作效应达1%的显著水平。按位点对加工品质性状的贡献大小,Glu-D1>Glu-B3>Glu-B1>Glu-A3>Glu-A1;就单个亚基而言,Glu-A1位点,1>2*>N;Glu-B1位点,7+8>14+15>7+9;Glu-D1位点,5+10>4+12>2+12;Glu-A3位点,Glu-A3d>Glu-A3a>Glu-A3c>Glu-A3e,Glu-B3位点; Glu-B3d>Glu-B3b>Glu-B3f >Glu-B3j。1B/1R易位对SDS沉降值、和面时间和耐揉性等加工品质性状有显著负面效应。通过选择优质高低分子量麦谷蛋白亚基和淘汰1B/1R易位系,将有助于提高我国小麦的面筋质量。 相似文献