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941.
为了提高中国厚皮类瓜果的品质质量和出口能力,增强中国水果品质检测装备制造业的技术实力和技术水平。该文以西瓜为对象,对其糖度进行了试验研究。由于西瓜各部位存在差异,因而不同部位采集近红外光谱会对糖度预测模型精度产生影响。采用自主搭建的西瓜内部品质检测系统对不同批次西瓜瓜梗、瓜脐和赤道3个部位采集漫透射光谱信息,分别采用偏最小二乘回归法(partial least squares regression,PLSR)和最小二乘支持向量机法(least squares support vector machines,LS-SVM)2种方法对西瓜糖度建立预测模型,考察西瓜不同检测部位对西瓜糖度预测模型精度的影响。2种预测模型均显示,赤道部位采集光谱所建立的预测模型检测精度较差,而采用瓜脐部位获取光谱信息建立预测模型略好于瓜梗部位,最佳预测相关系数rpre达到0.823,预测均方根误差(root mean square error of prediction,RMSEP)为0.652%。该研究结果表明,不同部位采集光谱信息对最终的检测模型精度有影响,瓜脐部位为该文西瓜内部品质检测装置的较优采集部位。 相似文献
942.
不同种源厚朴性状变异的初步研究 总被引:11,自引:0,他引:11
厚朴不同种源树叶形状从先端急关到裂成2钝圆裂片,存在渐变过程,又有遗传稳定性,大体上可以分为3个类型。不同种源厚朴苗木和幼林高生长、物候期、生长节律都存在明显的差异,差异的变异与树叶形状类型存在显著的相关。幼林高生长估算遗传力达到0.52~0.69,具有中等以上的遗传力。 相似文献
943.
Employing four mathematical models (first-order, parabolic-diffusion, Elovich and zero-order), kinetics of potassium desorption from eight soils with and without cropping were studied to evaluate their ability in explaining K release from soils. The decline in the soil test K in cropped soils over original soils was drastic in easily desorbable forms compared to that of strongly held forms like 3 M H2SO4 K. Results showed that parabolic diffusion as well as first-order kinetic equation explained the K release data well for both original and K depleted (cropped) soils. Elovich and zero-order equations were not suitable to describe the kinetic data. However, zero-order equation explained K release data better in case of K-depleted soils as compared to original soils. Soils with higher initial K contents registered higher release rate constants. Over the entire period of cropping the range of release rate (b) decreased from 1.26 to 1.53 × 10?2 to values ranging from 1.12 to 1.30 × 10?2 h?1. In contrast, the first-order equation, parabolic diffusion showed higher b values for cropped soils as they represent the diffusion gradient. Mica and its biotite content in both silt and clay fractions showed significant correlation (r) with b values. Similarly with the rate of K release, clay content of soils maintained significant r whereas the silt content did not. 相似文献
944.
945.
Peter Wenzl Alba L. Chaves Gloria M. Patio Jorge E. Mayer Idupulapati M. Rao 《植物养料与土壤学杂志》2002,165(5):582-588
Aluminum‐resistant Brachiaria decumbens Stapf cv. Basilisk (signalgrass) and closely related, but less resistant Brachiaria ruziziensis Germain & Evrard cv. Common (ruzigrass) both accumulated high concentrations of aluminum (Al) in roots. Approximately two thirds of the total Al was complexed by soluble low‐molecular‐weight ligands, suggesting that it had been taken up into the symplasm. We therefore investigated whether these species might employ Al‐chelating organic acids for internal detoxification of Al taken up by root apices, the primary site of Al injury. Unlike root apices of other Al‐resistant plant genotypes, which secrete organic‐acid anions to detoxify Al externally, apices of Brachiaria species accumulated organic acids within the tissue. A comparison with whole roots showed that this preference for accumulation (as opposed to secretion) was restricted to apices. Citric acid, and to a lesser extent trans‐aconitic acid, accumulated in a uniform dose‐dependent manner in root apices of both species as their Al content increased under Al‐toxic growth conditions. Their accumulation was accompanied by a stimulation of malate synthesis in Al‐resistant B. decumbens, while it occurred at the expense of malate in Al‐sensitive B. ruziziensis. These data suggest a role of organic acids in the internal detoxification of Al in root apices of both Brachiaria species, presumably contributing to their comparatively high basal level of Al resistance. Yet internal detoxification of Al by organic acids does not appear to be the principal mechanism responsible for the superior resistance of B. decumbens. 相似文献
946.
The Expansin protein is known for its multifaceted roles in plant growth, especially cell walls. However, very few studies have been done so far to assess the effects of expansin genes on Cotton fibre development. The present study is a successful effort to fill this gap, where the α-EXPA1 gene transformed into a local cotton variety, Gossypium hirsutum, through Agrobacterium-mediated transformation under Gossypium hirsutum Seed coat and Fibre-specific promoter (GhSCFP). The transgenic cotton plants underwent molecular characterization and fibre trait evaluation. Our results indicated that α-EXPA1 showed an up-regulated expression during the transition phase of secondary cell wall synthesis and resulted in improving the fibre parameters, especially micronaire value. Transgenic cotton fibre also showed a finer twisting under the Scanning electron microscope (SEM) as compared to non-transgenic cotton fibre samples. The fibre production is influenced by more than nine thousand genes, and the fibre improvement cannot be just achieved through a single gene transformation. However, α-EXPA1 is one of the potential candidates for cotton fibre research as it significantly improved the cotton fibre. 相似文献
947.
Rao Duvvarapu Easwar Chaitanya Kolluru Viswanatha 《Journal of Crop Science and Biotechnology》2019,22(4):355-362
Journal of Crop Science and Biotechnology - Soybean is an economically important crop used as a vital source of oil, vegetable protein, and other commercial products. Cultivation of soybean fetches... 相似文献
948.
荔枝原产于中国,荔枝古树资源的开发创新利用是荔枝育种的重要工作之一,通过褐毛荔古树资源的调查,系统掌握古树资源情况,对特异资源进行收集保存,为后续荔枝育种研究提供依据。本研究简述了国内荔枝古树资源调查研究进展以及褐毛荔种质资源选育及功能性成分研究。对褐毛荔古树资源在云南区域分布的经纬度(101.70°—103.88°E、22.57°—25.03°N)、海拔(93~1441 m)、生长情况、成熟期,叶果性状及品质等进行分析。指出褐毛荔古树资源面临的濒死问题,最后提出褐毛荔古树资源的保护建议。 相似文献
949.
950.