水稻不同发育时期高光谱与叶绿素和类胡萝卜素的变化规律

通过大田和室内试验,测定了2个品种、3个供氮水平处理的水稻冠层、完全展开倒1叶、倒3叶和穗在不同发育时期的高光谱反射率及对应叶片和穗的叶绿素、类胡萝卜素含量。结果表明,不同供氮水平的水稻冠层和叶片光谱差异明显,冠层光谱反射率随发育期推迟,抽穗前在可见光范围逐渐降低、在近红外区域逐渐增大,抽穗后在可见光范围逐渐增大,在近红外区域逐渐降低;抽穗后,冠层、叶片和穗光谱的红边位置存在“蓝移”现象;叶片叶绿素、类胡萝卜素含量呈S形变化;高光谱植被指数R990/R553、R1200/R553、R750/R553、R553/R670、R800/R553、R800/R680、（R800-R680）/（R800+R680）［R为反射率,下标为对应波长值（nm)］和红边位置λred与叶绿素、类胡萝卜素含量之间存在极显著相关,说明能用它们来估算水稻冠层、叶片和穗的叶绿素、类胡萝卜素含量。     

玉米叶片高光谱反射率、吸收率与色素含量的关系比较分析

分析测定了大田试验条件下11个玉米品种的3个氮肥处理、2个密度处理和6个生育期的150张叶片在350～2500nm波段的反射率和吸收率及其叶绿素a、叶绿素b和类胡萝卜素的含量。玉米叶片在叶绿素吸收波段的最大吸收波长位于665nm附近,665nm处叶片的吸收率与反射率间呈高度负相关(R2=-0.7533,n=150),而吸收率较高(>92%)的叶片的相关性明显强于吸收率较低的叶片。基于近红外波段和叶绿素吸收波段(红波段)或叶绿素反射波段(绿波段)构建的8个高光谱参量只有以反射率为基础计算时才与色素含量间存在相关性。mSR705和mND705无论以反射率还是以吸收率为基础计算,均表现出与色素含量间的强相关关系,而以吸收率为基础计算的mSR705和mND705与色素含量间的相关性又稍强于以反射率为基础计算的mSR705和mND705。本研究结果暗示叶片的表面反射是干扰叶片光谱(尤其是吸收光谱)对色素浓度变化响应的主要因子。     

不同施肥处理花生反射光谱与产量相关性研究

了解不同施肥条件下花生叶片光谱反射率与产量的相互关系,设计包含7种施肥处理、3次重复的田间试验,在主要生育期测定叶片光谱反射率和功能叶叶绿素的相对含量。结果表明,随生育期推进不同施肥处理叶片SPAD值呈现相似的先升后降的变化趋势;不同施肥条件花生叶片的光谱曲线相似,但不同波段光谱反射率大小存在一定程度的差异;"低肥+钙肥+锌肥+根瘤菌"施肥处理产量高于其他施肥处理,其中钙肥增产效果明显;开花下针期、结荚期、饱果成熟期花生叶片光谱与产量相关性较好,其中在结荚期花生叶片光谱与产量相关性最好。花生叶片光谱特征波段与产量之间具有较密切的关系,可利用叶片光谱反射率监测花生营养状况。     

基于冠层反射光谱的夏玉米叶片色素含量估算模型研究

通过分析不同施氮水平下夏玉米叶片色素含量与冠层光谱反射率及其衍生的比值植被指数(RVI)、归一化植被指数(NDVI)、正交植被指数(MTVI2、MCARI2、SAVI、MSAVI)以及叶绿素吸收比值指数(CARI)之间的关系,建立夏玉米叶片叶绿素a(Chla)、叶绿素b(Chlb)、叶绿素a+b(Chl a+b)和类胡萝卜素(Car)含量估算模型。结果表明:NDVI与夏玉米叶片色素含量的相关性最好,RVI、RVI、CARI位居其次。通过逐步回归分析确立的夏玉米叶片Chla、Chlb、Chl a+b及Car含量的估算模型R2分别为0.790 8、0.832 4、0.808 8和0.761 7,说明利用冠层NDVI可以对夏玉米叶片Chla、Chlb、Chl a+b和Car含量进行可靠的监测。     

用高光谱植被指数估算水稻乳熟后叶片和穗的色素含量

 分析测定了大田条件下2个水稻品种在3个氮素水平下的剑叶和穗从乳熟期至收割的光谱反射率(350~2500 nm)及对应剑叶和穗的叶绿素（Chl）、类胡萝卜素（Car）含量,并利用相关分析研究了11个植被指数与剑叶、穗的叶绿素含量之间的关系。mSR705、mND705在试验范围各叶绿素含量水平下，都表现极显著的相关性。mSR705、mND705与叶片、穗叶绿素含量进行线性回归，两者拟合R2分别为0.9319和0.9488（n＝48）。植被指数与类胡萝卜素、Car/Chl间的相关性分析表明，光化学反射指数（PRI）与剑叶、穗Car/Chl都有很好的负相关（R2=0.7745，n=48）, 可以用来预测不同植被结构的Car/Chl;R760/R500与剑叶Car/Chl和穗Car含量也具有较好的相关性。结果表明，mSR705、mND705和PRI等指数可用于估算叶片、穗的色素含量，作为水稻成熟度的监测指标。     

甘蔗苗期不同叶位叶绿素荧光特性研究

为明确不同叶位和叶片不同部位叶绿素荧光特性的分布规律及其随生长时间的变化规律,进而实现甘蔗光合潜力的快速评价,本研究通过桶栽试验对3个甘蔗主栽品种（ROC22、ROC16、桂柳05-136）不同叶位和叶片不同部位的叶绿素荧光特性进行比较分析,并研究叶绿素荧光参数对生长时间的响应。结果表明：光系统II（PSII）量子效率（ΦII）随着倒数叶位的增加而下降,在叶片不同部位之间表现为叶中部>叶尖端>叶基部,相同叶位不同品种间ΦII的差异不显著;可调节性能量耗散（ΦNPQ）则随着倒数叶位的增加而上升;非调节性能量耗散（ΦNO）在不同叶位（除倒四叶）及品种间并无显著差异。随着生长时间的推进,上部叶位具有较高的ΦII和较低的ΦNPQ;中部叶位的ΦII和光化学猝灭（qL）变化很小;下部叶位在叶片生长的前两周,能量分配在ΦII和ΦNPQ之间进行,ΦNO基本保持不变;而超过3周后,3个供试品种的ΦII、qL和最大光能利用效率（Fv/Fm）均有不同程度的下降,降幅为ΦII>qL>Fv/Fm,同时伴随着ΦNO的增加。上述结果表明光能利用效率以上部叶位最高,中部叶位稳定,而下部叶位最低且差异较为显著。而不同叶位相对电子传递速率（rETR）对生长时间的响应研究表明,在苗期上部第一片全展叶的中部叶位光能转化能力最强,可选择该叶片的中部叶位进行叶绿素荧光特性横向比较。本研究初步明确了不同叶位光能的利用效率及其随生长时间的变化趋势,为如何选择合适的叶位进行叶绿素荧光检测,进而开展甘蔗冠层光合潜力的快速评价奠定基础。     

应用SPAD值预测小麦叶片叶绿素和氮含量的初步研究

2003～2004年以中筋小麦品种扬麦11号、WH510和徐州26为试验材料,研究不同生育时期(拔节、孕穗、抽穗)不同叶位叶片SPAD值变化特征及其与叶片叶绿素含量、全氮含量及NO3--N含量的关系,旨在为小麦上应用SPAD快速诊断施肥提供理论依据。结果表明,不同品种及不同叶位小麦叶片SPAD值明显不同;小麦叶片SPAD值与叶绿素含量之间的关系因品种和生育时期的不同而有明显差异,同一品种小麦不同叶位叶片SPAD值与叶绿素含量呈极显著正相关。小麦叶片SPAD值与全氮含量呈正相关,SPAD值高,全氮含量也高,可以用SPAD值估算全氮含量进行小麦氮素营养状况诊断,但同一品种不同叶位SPAD值与全氮含量的关系表现不一致,即用SPAD值来诊断小麦叶片氮含量时应选择完全展开并已进入功能盛期的叶片。小麦叶片SPAD值与NO3-N含量相关性不显著。     

玉米和高粱叶片叶绿素含量及动态的比较

对玉米品种油试67和高粱品种LA5×36不同时期叶片的叶绿素含量(SPAD值)进行了比较研究.结果表明:二作物的SPAD值在前期大小相近,高粱略高于玉米;中后期玉米叶片SPAD值下降速度较快,叶片衰老与籽粒成熟同步性强,而高粱叶片的持绿性较强.玉米不同叶位SPAD值变化幅度比高粱大,主要表现在低叶位叶片和高叶位叶片数值较低.玉米棒三叶的SPAD值较高.     

浓香型烟叶成熟期质体色素的变化特征研究

为探明湖南浓香型烟叶质体色素在生育后期不同阶段和不同叶位间的差异,对云烟87在打顶期、打顶后10 d、打顶后20 d三个时期和上部、中部及下部叶三个叶位间的色素含量变化及叶绿素含量与SPAD值的关系进行了研究。结果表明：同一时期不同叶位叶绿素a、叶绿素b和总叶绿素含量都表现为：上部叶〉中部叶〉下部叶,除打顶期上部叶和中部叶差异不显著外,不同叶位差异达极显著水平;同一叶位不同时期叶绿素含量变化为,打顶期后下部叶逐步明显减少,中部叶先明显减少后少量增加,上部叶则先增加后降低。不同叶位类胡萝卜素的含量变化在同一时期都表现为：上部叶〉中部叶〉下部叶,且叶位间存在显著性差异。叶绿素a与叶绿素b含量比值和总叶绿素与类胡萝卜素比值在相同时期都表现为：上部叶〉中部叶〉下部叶,但前者在打顶期后呈逐渐降低趋势,后者则先增加后明显减少。上部叶、中部叶及下部叶的叶绿素含量均与相应SPAD值具有极显著正相关性。     

利用GreenSeeker法诊断春玉米氮素营养状况的研究

利用GreenSeeker对不同氮素处理春玉米冠层和叶片进行了测定,分析了植被指数(NDVI)和叶片叶绿素a(Chla)含量和氮素(N)含量的相关性。结果表明,不同氮素处理冠层NDVI变化与叶片叶绿素a含量在整个生育期内变化趋势一致。NDVI对叶绿素变化最敏感的时期是大喇叭口期。从不同叶位的变化趋势看,NDVI随CHla、N含量的变化而表现出明显的变化,三者之间具有显著的直线相关关系。利用GreenSeeker获取的NDVI值为生产中诊断春玉米叶绿素或氮素状况提供了有效手段。     

Sorghum and millet phenols and antioxidants

Sorghum is a good source of phenolic compounds with a variety of genetically dependent types and levels including phenolic acids, flavonoids, and condensed tannins. Most sorghums do not contain condensed tannins, but all contain phenolic acids. Pigmented sorghums contain unique anthocyanins that could be potential food colorants. Some sorghums have a prominent pigmented testa that contains condensed tannins composed of flavan-3-ols with variable length. Flavan-3-ols of up to 8–10 units have been separated and quantitatively analyzed. These tannin sorghums are excellent antioxidants, which slow hydrolysis in foods, produce naturally dark-colored products and increase the dietary fiber levels of food products. Sorghums have high concentration of 3-deoxyanthocyanins (i.e. luteolinidin and apigenidin) that give stable pigments at high pH. Pigmented and tannin sorghum varieties have high antioxidant levels that are comparable to fruits and vegetables. Finger millet has tannins in some varieties that contain a red testa. There are limited data on the phenolic compounds in millets; only phenolic acids and flavones have been identified.     

Tuber and starch quality of wild and cultivated potato species and cultivars

Summary Between 1993 and 1998 205 different potato cultivars and 1220 accessions/genotypes of wild and cultivated potato species from the IPK Genebank Gatersleben were evaluated. Parameters interesting for starch isolation and especially for the use of starch were determined. Altogether, there was a higher variability in wild potato species than in cultivated potatoes for all characteristics investigated: dry matter content, starch content, protein content, amylose content and mean particle diameter of starch granules.     

Effects of Organic and Chemical Fertilizers and Arbuscular Mycorrhizal Inoculation on Growth and Quality of Cucumber and Lettuce

Summary

Arbuscular mycorrhizae were inoculated into phosphorus-deficient soil fertilized with either organic or chemical fertilizer with cucumber (Cucumis sativus L.) as the first crop and lettuce (Lactu-ca sativa L.) as the second crop but without additional fertilization and AM inoculation. AM increased dry matter and fruit yield of cucumber significantly in the unfertilized, organic-fertilized and P-deficient plants compared with the fully chemical-fertilized plants. AM inoculation increased the available phosphorus in plant and soil by around 30% for all treatments except for those chemically-fertilized. The rate of AM infection did not differ significantly among the fertilization treatments, but the infection intensity was higher in unfertilized, organic-fertilized and phosphorus-deficient treatments than chemical-fertilized treatment. The residual effects of AM-inoculated to cucumber were evident for lettuce in all pre-treatments that were unfertilized and un-inoculated for the second cropping. Without P-fertilization, neither crop could grow optimally even when the soil was inoculated with AM, suggesting that AM could not serve as a substitute for phosphorus fertilizer. However, the other beneficial effects of AM on crop growth and yield could not be fulfilled with phosphorus fertilizer.     

种子加工、检验理论与技术现状及思考

种子加工及检验是种子向市场流通的关键，是商业化育种中赋予种子商品属性不可或缺的环节。种子加工、检验理论与技术的研究是完善种业产业链、实现规模化商业育种、夯实“育繁推一体化”种业科学的重要一环。中国的种业科学技术体系正在形成与完善之中，受制于行业发展水平，种子加工及检验理论与技术相对薄弱。本文回顾了种子加工及检验理论与技术研究发展历程，提出了完善中国种业科学发展的策略与建议。围绕种业发展的需要，在做好品种优质化繁育的基础上，分析种子加工及检验理论与技术的新方向和新需求，加强种业应用性研究，建立先进的种子质量检验体系，研制适合现代种业发展需求的种子加工设备，打造种子加工产业标准化生产体系，完善种业科学技术学科建设，促进种业产业持续健康发展。     

Present Situation and Consideration of Seed Processing and Testing Theory and Technology

Seed processing and testing hold the key to the market circulation of seeds, and are an indispensable link in commercial breeding to endow seeds with commodity attributes. The research of seed processing and testing theory and technology is an important link in improving the seed industry chain, realizing large-scale commercial breeding and consolidating the seed industry science of ‘integration of breeding, propagation and promotion’. The scientific and technological system of seed industry in China is being formed and perfected, which is subject to the development level of the industry. The theory and technology of seed processing and testing are relatively weak. We reviewed the development of seed processing and testing theory and technology, and put forward strategies and suggestions to improve the sound development of China’s seed industry. In order to meet the needs of seed industry development and on the basis of high quality breeding of varieties, the new directions and demands of seed processing and testing theory and technology were analyzed. We will work to strengthen the applied research of seed industry, establish advanced seed quality inspection system, improve seed processing equipment suitable for the development needs of modern seed industry, establish standardized production system of seed processing industry, develop the scientific and technological disciplines of seed industry, and promote the sustainable and healthy development of seed industry.     

种子加工、检验理论与技术现状及思考

种子加工及检验是种子向市场流通的关键,是商业化育种中赋予种子商品属性不可或缺的环节。种子加工、检验理论与技术的研究是完善种业产业链、实现规模化商业育种、夯实"育繁推一体化"种业科学的重要一环。中国的种业科学技术体系正在形成与完善之中,受制于行业发展水平,种子加工及检验理论与技术相对薄弱。本文回顾了种子加工及检验理论与技术研究发展历程,提出了完善中国种业科学发展的策略与建议。围绕种业发展的需要,在做好品种优质化繁育的基础上,分析种子加工及检验理论与技术的新方向和新需求,加强种业应用性研究,建立先进的种子质量检验体系,研制适合现代种业发展需求的种子加工设备,打造种子加工产业标准化生产体系,完善种业科学技术学科建设,促进种业产业持续健康发展。     

Combined nitrogen and sulphur fertilisation and its effect on wheat quality and protein composition measured by SE-FPLC and proteomics

Soil sulphur deficiency, which is increasingly prevalent in Western Europe, lowers wheat yields, and also affects the gluten quality of the flour. Differences in S availability may change the proportion of S-poor to S-rich gliadins and glutenin subunits. This may cause unpredictable and unwanted variations in wheat quality. The combined effects of nitrogen (N) and sulphur (S) fertilisers and split application of S and N on wheat gluten quality and composition were investigated. The results revealed effects of S fertilisation on dough quality. At high N fertilisation levels significant responses to S fertilisation were found which emphasised the need for precision application of S in intensive wheat production systems. Protein fractionation by SE-FPLC showed that quality differences were associated with changing proportions of high M_r polymeric proteins. Changes in protein composition of salt soluble proteins were also confirmed by proteomics. Glyceraldehyde-3-phosphate dehydrogenase and one of the serpin protein spots increased at high N, combined with the lower S level. The enzymes also increased in samples with increased S fertilisation combined with low N, but was not changed at higher N levels. Furthermore, at high N the serpin protein spot, and also a 27 K protein and one unidentified protein spot decreased with increasing S.     

我国麻类标准现状与分析

介绍了我国麻类标准的现状。通过分析,指出了存在的问题,主要表现在标准体系不完善、标准更新不及时,协调性差及贯彻执行不力等。提出了我国麻类标准应采取的对策。     

芸薹属多倍体与二倍体作物 花柱及角果的发育差异

通过比较分析芸薹属多倍体复合种与其祖先二倍体基本种在花柱、柱头大小、角果长度、宽度、种子直径 及种子干重变化上的异同,发现多倍体复合种在这些发育性状上表现出处于两个祖先二倍体亲本之间,或只偏向 于其中一个祖先亲本。同一个多倍体品种在不同发育性状上具有不同的表现,即在某一发育性状上偏向于其祖先 亲本之一,而在另一发育性状上偏向其另一祖先亲本。     

Effects of crop density and tillage system on grain yield and N uptake from soil and atmosphere of sole and intercropped pea and oat

Pea (Pisum sativum L.) and oat (Avena sativa L.) were grown as sole and mixed crops in various densities under two different tillage systems on a loess soil near Göttingen/Germany in a 2-year field experiment (2002/2003). In the conventional tillage system a mouldboard plough (CT) was used and in the minimum tillage system a rotary harrow (MT) was employed. The effect of crop density and tillage system on the grain dry matter and grain N yields, N₂ fixation and soil N uptake were determined to address the following questions: (i) which mixture compositions exhibit the highest grain yields compared to the sole crops, (ii) which mixture compositions also fix a high level of N₂ and leave low levels of residual inorganic soil N after harvest, and (iii) whether the intercrop advantage is influenced by the tillage system. For (i) the result in 2002 showed that the highest grain yields of both sole cropped pea and oat and intercropped pea and oat were achieved at the highest densities. In 2003, when the inorganic soil N content was higher and weather conditions were warmer and drier, grain yields were significantly higher than in 2002, but sole as well as intercropped pea and oat gave their highest grain yields at lower densities. For both years and tillage systems, the highest intercrop advantages were achieved in mixtures with densities above the optimal sole crop densities. The result for (ii) was that a distinctly higher proportion of nitrogen was derived from the atmosphere (Ndfa) by intercropped pea than by sole cropped pea. However, the uptake of soil N by intercropped pea and oat was not reduced in comparison with that of sole cropped oat as the decrease in the uptake of N from the soil by oat at lower oat densities in the mixture was compensated for by the soil N uptake of pea. Additionally, the N_min-N content of the soil following the mixtures and sole cropped oat did not differ, especially in the deeper soil layers because oat in mixture was forced to take up more soil N from deeper layers. Therefore, the risk of soil N losses through leaching after mixtures was lower compared to sole cropped pea. The tillage system (iii) had no significant influence on grain yield and soil N uptake, but N₂ fixation and the competitive ability of intercropped pea were higher under CT than with MT. An additional result was that intercropping led to a significantly increased grain N content of both pea and oat compared to the sole crops. The increase in grain N content from sole to intercrop was from 3.30 to 3.42% for pea and from 1.73 to 1.96% for oat as a mean for both years and tillage systems. The present study confirms that growing pea and oat as intercrops highlights potential economic and environmental benefits which still need to be understood in more detail in order to exploit intercropping to a greater extent.