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Slight shading after anthesis increases photosynthetic productivity and grain yield of winter wheat (Triticum aestivum L.) due to the delaying of leaf senescence

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Journal of Integrative Agriculture 2016年第1期15卷 63-75页

作者： XU Cai-long TAO Hong-bin wang Pu wang zhen-lin College of Agriculture and Biotechnology China Agricultural University National Key Laboratory of Crop Biology Agronomy College Shandong Agricultural University

The solar radiation intensity and duration are continuously decreasing in the major wheat planting area of China. As a con- sequence, leaf senescence, photosynthesis, grain filling and thus wheat yield shall be affected by light deficiency. Therefore, two winter wheat （Triticum aestivum L.） cultivars, Tainong 18 （a large-spike cultivar） and Ji＇nan 17 （a multiple-spike cultivar）, were subjected to shading during anthesis and maturity under field condition in 2010-2011 and 2011-2012. Under the slight shading treatment （$1,88% of full sunshine）, leaf senescence was delayed, net photosynthesis rate （Po） and canopy apparent photosynthesis rate （CAP） were improved, and thus thousand-kernel weight （TKW） and grain yield were higher as compared with the control. However, mid and severe shading （S2 andS3, 67 and 35% of full sunshine, respectively） led to negative effects on these traits substantially. Moreover, superoxide dismutase （SOD）, peroxidase （POD） and cat- alase （CAT） activities in flag leaf were significantly greater under slight shading than those in other treatments, while the malondialdehyde （MDA） content was less than that under other treatments. In addition, the multiple-spike cultivar is more tolerant to shading than large-spike cultivar. In conclusion, slight shading after anthesis delayed leaf senescence, enhanced photosynthesis and grain filling, and thus resulted in higher grain yield.

关键词： winter wheat shading photosynthesis leaf senescence grain yield

Observation of Optical Bistability in Two-Dimensional Volume Refractive Index Grating Thermally Fixed in linbO_(3):Fe Crystal

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Chinese Physics Letters 1996年第6期13卷 440-443页

作者： wang zhen-lin WU Jun YANG zhen-ju ZHU Yong-yuan Min Nai-ben National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

Experimental observation of optical bistability in a nonlinear two-dimensional volume refractive index grating is *** index grating in linbO_(3):0.1 wt.%Fe photorefractive single crystal was fabricated by using hologram recording and subsequent thermal fixing *** to the thermal fixing,the stored 2D volume index grating shows no optical erasure during *** explanation of the nonlinear phenomena is also given in terms of the intensity-enhanced bulk photovoltaic effects in linbO_(3):Fe material.

关键词： stability Refractive nonlinear

Slow-Light Propagation in a Tapered Dielectric Periodic Waveguide over Broad Frequency Range

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Chinese Physics Letters 2011年第5期28卷 132-135页

作者： FANG Yi-Jiao CHEN Zhuo wang zhen-lin Department of Physics and National Laboratory of Solid State Microstructures Nanjing UniversityNanjing 210093

A tapered waveguide composed of a one-dimensional periodic arrangement of dielectric materialis proposed for light *** equifrequency contours(EFC)of silicon-air multilayer photonic crystals within the first bandgap region are first studied.A zero-group-velocity at the first Brillouin zone boundary along the grating vector is *** propagation constants and eigenfrequencies of the first-order guiding modes are numerically investigated for photonic crystal waveguide structures with a finite *** frequency components of the guiding modes are found to slov and stop at different thicknesses inside such a tapered waveguide *** addition,the time-evolution of a femto-second pulse propagating in the tapered waveguide is also demonstrated.

关键词： waveguide Waveguide arrangement

Physiological basis for the differences of productive capacity among tillers in winter wheat

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Journal of Integrative Agriculture 2015年第10期14卷 1958-1970页

作者： XU Hai-cheng CAI Tie wang zhen-lin HE Ming-rong National Key Laboratory of Crop Biology Ministry of Science and Technology/Agronomy College Shandong Agricultural University Institute of Water-Saving Agriculture in Arid Areas of China Agronomy College Northwest A&F University

The quality or structure of a wheat population is significantly affected by the compositions of tillers. Little has been known about the physiological basis for the differences of productive capacity among tillers. Two winter wheat cultivars, Shannong 15（SN15） and Shannong 8355（SN8355）, were used to investigate the differences of productive capacity among tillers and analyze the physiological mechanisms that determine the superior tiller group. Low-position tillers（early initiated tillers） had a higher yield per spike than high-position tillers（late initiated tillers） in both cultivars, which was due to their more grain number per spike, more fertile spikelet per spike, less sterile spikelet per spike and higher grain weight. According to cluster analysis, tillers of SN15 were classified into 2 groups： superior tiller group including main stem（0）, the first primary tiller（I） and the second primary tiller（II）; and inferior tiller group including the third primary tiller（III） and the first secondary tiller（I-p）. Tillers of SN8355 were classified into 3 groups： superior tiller group（0 and I）, intermediate tiller group（II and III） and inferior tiller group（I-p）. In comparison with other tiller groups, the superior tiller group had higher photosynthetic rate of flag leaves, higher antioxidant enzyme（SOD, POD and CAT） activities and lower levels of lipid peroxidation in leaves, higher grain filling rate in both superior and inferior grains during grain filling, higher single-stem biological yield and larger single-stem economic coefficient. Correlation analysis showed that yield per spike was positively and significantly correlated with the flag leaf photosynthetic rate, grain filling rate, the antioxidant enzyme activities and soluble protein content（except for SN15 at 5 days post-anthesis（DPA）） of flag leaf, the single-stem biological yield, and the single-stem economic coefficient. Remarkable negative correlation was also found between yield per spike and MDA content o

关键词： enzyme activities grain filling photosynthetic rate productive capacity tillers wheat(Triticum aestivum L.)

Endogenous Hormone Concentration in Developing Tuberous Roots of Different Sweet Potato Genotypes

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Agricultural Sciences in China 2006年第12期5卷 919-927页

作者： wang Qing-mei ZHANG Li-ming GUAN Yah-an wang zhen-lin Agronomy Faculty Shandong Agricultural University/Shandong Provincial Laboratory of Crop Biology Taian 271018 P.R.China Crop Research Institute Shandong Academy of Agricultural Sciences Jinan 250100 P.R.China

A field trial was conducted to investigate the changes of endogenous hormone concentration （EHC） during formation and thickening of tuberous roots in sweet potato （Ipomoea batatas L.） of different genotypes： Xushu 18, Minamiyutaka, and L trifida-K123. The results of this study suggested that the concentrations of zeatin riboside （ZR）, dihydro-zeatin riboside （DHZR）, abscisic acid （ABA）, indole-3-acetic acid （IAA）, and isopentenyl-adenine （IPA） of Xushu 18 and Minamiyutaka were significantly higher than those of I. trifida-K123. Dry tuberous root yields were positively correlated with the concentration of ABA, ZR, and DHZR at 1 or 5% significant level, but were not obviously correlated with the concentrations of IAA, IPA, and GA4. The concentrations of ABA, ZR and DHZR played very important roles in the tuberous root formation and thickening in sweet potato. The concentrations of ZR, DHZR, ABA, and IAA in the upper or inner portion of tuberous roots were significantly higher than those toward the end of the root or its outer portion. Meanwhile, EHC of large-sized tuberous roots were significantly higher than those of medium- or small-sized tubers during the early thickening period. In the rapid thickening period of tuberous roots, EHC of medium-sized tubers were the highest, However, at the late-thickening period, EHC of small-sized tubers ranked the highest.

关键词： sweet potato tuber endogenous hormone concentration (EHC) formation thickening

Physiological and Molecular Response of Wheat Roots to Nitrate Supply in Seedling Stage

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Agricultural Sciences in China 2011年第5期10卷 695-704页

作者： wang Ping wang zhen-lin CAI Rui-guo LI Yong CHEN Xiao-guang YIN Yan-ping State Key Laboratory of Crop Biology/Shandong Key Laboratory of Crop Biology/Agronomy College Shandong Agricultural University Tai＇an 271018 P.R.China Agronomy Department Hebei Normal University of Science and Technology Changli 066600 P.R. China

The objective of this study was to understand the morphological,physiological,and molecular responses of wheat roots to nitrate supply at seedling *** wheat genotypes,Jimai 22 and Shannong 15,were grown in Hoagland＇s nutrient solution with different nitrate levels at seedling *** indicated that the plant dry weight and N accumulation increased with the increase of nitrate *** number of axial root,total uptake area （TUA）,and active uptake area （AUA） increased with more nitrate *** analysis indicated that significant positive correlations existed between N accumulation and dry weight,N accumulation and AUA,and N accumulation and AUA/***,the expressions of NRT2.1,NRT2.2,and NRT2.3 decreased with nitrate supply increased,the expressions of NRT1,NRT2.1,and NRT2.3 could maintain high level at N3 *** free amino acid and NO3- content in shoot also increased with the increased nitrate application,but no significant difference was found in root among the *** results implied that the increase of N uptake by nitrate supply was due to the morphological and physiological responses of wheat roots and the high expression level of TaNRT ***,the contribution of morphological,physiological,and molecular parameters was different between two genotypes of wheat.

关键词： wheat root parameters nitrate uptake N metabolites TaNRT expression

Second-Harmonic Generation in Thue-Morse Optical Superlattice

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Chinese Physics Letters 1998年第6期15卷 426-428页

作者： LIU Xian-jie wang zhen-lin WU Jun MIN Nai-ben National Laboratory of Solid State Microstructures Nanjing Universityand Center for Advanced Studies in Science and Technology of MicrostructuresNanjing 210093

A Thue-Morse optical superlattice made from a single crystal with laminar ferroelectric domain structure was proposed to realize second-harmonic *** to the singular continuous Fourier spectrum in Thue-Morse sequence,this structure shows more plentiful harmonic spectrum,and the intense peaks can be classified according to their different intensity distributions within the *** harmonic spectra in real space and reciprocal space are presented and discussed.

关键词： Morse harmonic spectrum

Ordered Gold Nanobowl Arrays as Substrates for Surface-Enhanced Raman Spectroscopy

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Chinese Physics Letters 2011年第5期28卷 249-252页

作者： CHEN ling LIU Fan-Xin ZHAN Peng PAN Jian wang zhen-lin National Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210093

We demonstrate that an interlinked gold half-shell array fabricated by metal deposition on a sacrificial twodimensional colloidal crystal template can show a large enhancement in surface-enhanced Raman spectroscopy at its main transmission *** isfurther observed that Raman signal enhancement shows a noticeable difference when reversing the orientations of the Au nanobowls in relation to the underlying flat dielectric *** the pump laser wavelength is tuned in the vicinity of the resonant plasmonic mode of the structure,the nhancement on an upward Au nanobowl array can be five-fold compared to that on a downward *** simulation confirms that for the upward nanobowls,a strong localized mode inside the Au nanobowls is formed at the resonant excitation wavelength,which helps to explain this observed extra enhancement in Raman scattering.

关键词： pump resonant mode

Phase noise sensitivity analysis of lattice constellation

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 36-40页

作者： YU Guang-wei NIU Kai HE Zhi-qiang wang Xu-zhen lin Jia-ru Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Based on the assumption of large number of constellation points and high signal-to-noise ratio （SNR）, phase noise sensitivity of lattice constellation is analyzed. The upper bound of symbol error rate （SER） in additive white Gaussian noise （AWGN） channel is derived from pairwise error probability. For small phase noise, phase noise channel is transformed to AWGN channel. With the aid of Wiener model, the obtained upper bound can be extended to phase noise channel. The proposed upper bound can be used as performance criterion to analyze the sensitivity of phase noise in multi-dimensional lattice constellation. Simulation results show that with the same normalized spectral efficiency, higher dimensional lattice constellations are more sensitive than lower ones in phase noise channel. It is also shown that with the same dimension of constellation, larger normalized spectral efficiency means more performance loss in phase noise channel.

关键词： lattice constellation symbol error rate (SER) phase noise