波兰小麦对普通小麦部分品质指标的改良作用

为了探讨波兰小麦对普通小麦品质指标的改良作用,测定了波兰小麦×中13杂交后代41个株系的蛋白质含量、沉降值及面筋含量.结果表明,杂交后代株系平均蛋白质含量、沉降值、干面筋含量和湿面筋含量都显著高于普通小麦亲本中13.杂交后代株系的蛋白质含量平均值与优质对照品种小偃6号间没有显著差异,而且有5个株系还高于对照,但杂交后代株系的平均沉降值和平均湿面筋舍量没有达到小偃6号的水平.BC1自交后代株系与BC2自交后代株系间的平均蛋白质含量和平均干、湿面筋含量没有显著性差异.这些结果表明,波兰小麦对普通小麦蛋白质含量、沉降值和面筋含量具有显著改良作用.     

水稻高无机磷突变体的筛选和培育技术研究

 摘要: 以3份水稻诱变群体为材料，详细研究了M2~M5代高无机磷(high inorganic phosphorus, HIP)种子出现的频率和传递特征。这些材料来自含水量约13.5%的水稻干种子用300 Gy 60Co伽玛射线 （剂量率0.8 Gy/min）处理，或经250 Gy 处理后再对其萌动种子用1×10-3 mol/L的 NaN3 溶液常温下处理2 h所得M1的后代。在96 孔V型酶标板上， 设置5个用KH2PO4配制的标准P溶液，浓度相当于种子磷含量0.00、 0.15、 0.46、 0.93和1.39 mg/g。分析时每个单株分析8粒种子，无机P（iP）高于0.46 mg/g的籽粒称为高无机磷（HIP）种子，出现至少1粒HIP M3种子的M2单株称为HIP M2单株，M3及高代由此类推。研究发现，从HIP M2单株衍生的M3株系中，HIP株系数要少于HIP M2单株数。但是多数M3 HIP株系后代都获得了更高代的HIP株系。根据M3和M4 HIP株系数推算，水稻HIP突变的实际频率可达0.1%左右。已从籼稻协青早B和粳稻秀水110中各选得一个HIP纯合突变系HIPi1和HIPj1。对HIPi1糙米中各种磷素定量分析表明，突变体中植酸磷含量较对照下降约35%，无机磷含量上升约3.5倍，而总磷基本不变。最后提出了水稻HIP突变体诱发、筛选和选择的基本方法和程序。     

不同玉米品种子粒植酸磷及其他形态磷含量的相关性研究

以50个自交系和24个杂交种为材料,测定其总磷、植酸磷、无机磷含量,分析不同基因型玉米子粒中植酸磷及其他形态磷含量的差异性和相关性。结果表明：不同自交系和杂交种间3种磷形态的含量均存在显著差异,植酸磷与总磷间呈正相关,与无机磷间呈弱度正相关。在低植酸玉米选育时,应该同时采用植酸磷和无机磷两个指标作为选择标准。自交系丹黄02是选育较低植酸磷、高无机磷含量杂交种的优良亲本材料。     

甘蓝型油菜种子无机磷含量变异的初步分析

以微量比色法对100个甘蓝型油菜品种的种子无机磷含量进行初步检测，发现不同甘蓝型油菜品种之间种子无机磷含量存在一定差异。大部分品种的成熟种子中无机磷含量为0.2-0.4μg/g，有2个品种的无机磷含量达到0.7μg/g,1个品种超过1.1μg/g。     

铁皮石斛与霍山石斛杂交后代性状分析

为选择杂交后代优良株系,对铁皮石斛（Dendrobium officinale）、霍山石斛（Dendrobium huoshanense）及其杂交F₁代株系的组培苗及栽培苗生长量、表型性状及多糖含量进行测定和分析。结果表明：各株系的组培生长量差异显著,变幅为0.15~0.69 g,超亲株系占75.00%,移栽生长量变幅为0.03~0.44 g,超亲株系占75.00%;组培苗8个表型性状表现为超亲,占总考察性状的88.89%;栽培苗4个表型性状表现为超亲,占总考察性状的44.44%,各株系多糖含量与亲本差异显著,7个株系的多糖含量表现为超亲,占总考察株系的87.50%。可见,利用铁皮石斛与霍山石斛杂交是改良石斛产量与品质的有效途径之一。     

微量面粉乳酸溶剂保持率在小麦育种后代选择中的应用

面粉乳酸溶剂保持率(solvent retention capacity SRC)是小麦品质检测的重要方法,为阐明其在小麦杂交后代分离群体中的遗传规律,以8个小麦杂交组合不同世代单株为材料,测定微量面粉乳酸溶剂保持率并进行分析。结果表明,亲本与后代的微量乳酸SRC值相关联,且后代单株微量乳酸SRC具有超亲优势;不同小麦杂交组合间微量乳酸SRC值均达到极显著差异;在8个杂交组合中同一株系微量乳酸SRC由第二代向第三代、由第三代向第四代传递不稳定且分离幅度大,而由第四代向第五、六代传递稳定,可见微量乳酸SRC值在系谱法后代处理中适合在第五代进行选择。这些研究结果可为优质小麦品种选育中杂交组合的配制及后代品质性状的选择提供参考依据。     

大豆不同亲本组合对后代品系油分含量的影响

设置"高油×高油"、"中油×高油"和"中油×低油"3种组合类型,对各组合类型后代品系油分含量进行分析测定,研究了大豆不同亲本组合对后代品系油分含量的影响。结果表明,大豆杂交组合亲本油分含量通过杂交后代群体对后代品系有显著影响,亲本油分含量与组合后代品系油分含量呈正相关。不同油分含量的大豆杂交亲本组合类型对后代品系油分含量有显著影响,同时受人为选择方式的影响。试验明确了大豆杂交后代群体油分含量的遗传过程及选择作用对后代品系油分含量的影响,为大豆品质育种实践提供参考。     

转Bt基因杂种后代的稻米直链淀粉含量与粘滞性淀粉谱分析

以克螟稻TS5为亲本与5个感虫亲本作正反杂交配组．分析了各组合后代抗虫株系和非抗虫株系及其双亲的直链淀粉含量（AAC）和粘滞性淀粉谱（RVA谱）。结果表明．杂种后代的AAC基本介于双亲之间，且偏向于高值亲本。AAC与最粘时间（PT）呈极显著正相关（0．7929）．与消减值（SBV）、最高粘度（PKV）、热浆粘度（HPV）、冷胶粘度（CPV）呈显著或极显著正相关，与崩解值呈负相关；杂种后代的RVA谱特征值与其双亲相比．无明显变化．但部分性状有所改善。这为抗虫杂交水稻的育种提供了参考依据。     

17个小麦F2群体中单株籽粒GMP含量的分布

为给GMP性状在后代中的选择提供依据,以17个小麦杂交组合的F2群体为材料,分析了单株籽粒GMP含量在不同组合F2群体中的分布状况.结果表明,不同组合的F2代单株籽粒GMP含量的分布是连续的,呈正态或偏态分布,符合数量性状遗传特点.在不同亲本的组合后代中,F2代单株籽粒GMP表现出不同的分布倾向,70.6%的组合以超高亲和倾高亲分布为主,出现23.5%近中亲和5.9%倾低亲分布,无超低亲分离现象.因此,在具有不同GMP含量亲本的杂交组合后代分离群体中,能够筛选出高GMP含量的育种材料.     

~(60)Co-γ辐照高产低植酸小麦新品系的鉴定筛选

通过辐射诱变手段获得种子低植酸(low phytic acid)突变系,进而选育低植酸作物品系,是可行的技术路径。本研究利用60Co-γ辐照小麦种子,从其后代中筛选到熟期与辐射亲本相仿或早熟、高产且籽粒植酸含量明显低于辐射亲本的小麦新品系10份,为小麦育种提供新的种质资源。     

Comparative Assessment of the Efficacy of Various Nitrogen Fertilizers

Summary

The efficiency of N fertilizers is usually poor; often less than 50% of the applied N is taken up by the crop. This review focuses on various N fertilizers with respect to the significance of different N loss pathways, namely (i) ammonia volatilization, (ii) dinitrogen and nitrogen oxide emissions, and (iii) nitrate leaching. Further, the significance of biological N immobilization, ammonium fixation and, finally, the impact of nitrate vs. ammonium uptake on crop yield are also discussed. The reviewed literature shows that N fertilizers may differ markedly in their susceptibility to losses. There is, however, considerable scope to improve N efficiency of each N source by proper N management practices.     

Novel food and non-food uses for sorghum and millets

Sorghum and millets have considerable potential in foods and beverages. As they are gluten-free they are suitable for coeliacs. Sorghum is also a potentially important source of nutraceuticals such antioxidant phenolics and cholesterol-lowering waxes. Cakes, cookies, pasta, a parboiled rice-like product and snack foods have been successfully produced from sorghum and, in some cases, millets. Wheat-free sorghum or millet bread remains the main challenge. Additives such as native and pre-gelatinised starches, hydrocolloids, fat, egg and rye pentosans improve bread quality. However, specific volumes are lower than those for wheat bread or gluten-free breads based on pure starches, and in many cases, breads tend to stale faster. Lager and stout beers with sorghum are brewed commercially. Sorghum's high-starch gelatinisation temperature and low beta-amylase activity remain problems with regard to complete substitution of barley malt with sorghum malt . The role of the sorghum endosperm matrix protein and cell wall components in limiting extract is a research focus. Brewing with millets is still at an experimental stage. Sorghum could be important for bioethanol and other bio-industrial products. Bioethanol research has focused on improving the economics of the process through cultivar selection, method development for low-quality grain and pre-processing to recover valuable by-products. Potential by-products such as the kafirin prolamin proteins and the pericarp wax have potential as bioplastic films and coatings for foods, primarily due to their hydrophobicity.     

Evolutionary aspects of the trade-off between seed size and number in crops

Whereas the concept that availability of resources drives seed production is sound in principle, it is incomplete as there are many solutions to the allocation of resources that derive from the trade-off between number and size. This paper examines evolutionary aspects of this trade-off in annual grain crops. The analysis is centred on the working hypotheses that, for a given species and environment, allocation of resources to reproduction involves (H1) high plasticity in seed number, which allows for variable resource availability, and (H2) a relatively narrow range of seed size that results from evolutionary and agronomic selection. Comparisons between crops and fish are used to highlight common evolutionary elements in taxa where parents provide little or no care to their offspring, with the consequence that both number and early survival of offspring, hence fitness of parents, are partially related to embryo size and reserves.

The plasticity of seed number in relation to availability of resources is analysed against the established relationship between offspring number and parent growth rate during critical stages. The notion that seed size is under stabilising selection is analysed against three conditions: (1) mean seed size is conservative for a given species and environment, (2) seed size affects fitness, and (3) seed size is heritable. Databases from published papers were compiled to analyse the relative variability of seed size and number, and the heritability of seed size. Evidence for and against the link between seed size and parental fitness is revised using the Smith–Fretwell model as framework (Am. Nat., 108, 499–506).

The proposal of high plasticity of seed number and narrow variability of seed size resulting from stabilising natural selection is generally consistent with evolutionary and genetic considerations. Agronomic selection may have reinforced natural selection leading to relatively narrow seed size in species such as wheat and soybean, where cultivated types retained high plasticity for seed number. In contrast, selection for one or few inflorescences in crops like sunflower and maize may have morphologically reduced seed number plasticity and increased variability of seed size and its responsiveness to resource availability in relation to their wild ancestors.     

Citrus Flavonoids in Fruit and Traditional Chinese Medicinal Food Ingredients in China

Flavonoids-enriched tissues of citrus such as peel, immature fruit and flower are consumed as culinary seasonings, tea ingredients in China for centuries. This HPLC quantitative study on the five citrus flavonoids, naringin, hesperidin, neohesperidin, sinensetin and nobiletin on a wide range of Chinese citrus fruits and several Traditional Chinese Medicinal food ingredients in East China, revealed a great diversity in flavonoid composition. Huyou peel (C. paradisi cv. Changshanhuyou) was found to be the best naringin (3.25%) and neohesperidin (2.76%) source; C. aurantium, a major ingredient of several citrus-related TCM, is also a suitable source of naringin and neohesperidin, and a good juice source for flavanone glycosides; the peel of Wenzhoumiju (C. unshiu) is one of the richest local species in hesperidin (up to 6.25%); Zaoju (C. subcompressa) has the highest content of nobiletin (0.59%), a polymethoxylated flavone. LC-ES-MS analysis of Zanthoxylum genus for flavonoids revealed for the first time the presence of significant amounts (0.74%) of hesperidin in the root of Liangmianzhen (Z. nitidum (Roxb.) DC), a relative of Sichuan pepper, which is a spice widely used in China.     

Effect of a continuous hot water treatment of potato tubers on seed-borne fungal pathogens

Summary The viability of five pathogens was decreased by treatment with hot water when tested in vitro.Polyscytalum pustulans was most sensitive andRhizoctonia solani least sensitive. Potato tubers were exposed to 55°C for 5 min in a commercial continuous hot water treatment plant using naturally contaminated seed tubers and tubers which had been inoculated by dipping in comminuted cultures. The frequency of eyes colonised byP. pustulans, Helminthosporium solani, andR. solani was reduced to virtually zero and the effect persisted on tubers subsequently stored at 4°C and at 15°C for up to 16 wk. Results withColletotrichum coccodes were inconclusive. Treatment suppressedPenicillium spp. which, however, rapidly recolonised the eyes during storage, leading to higher contamination levels in the treated than in the untreated tubers. With tubers inoculated withPhoma foveata, good control was achieved when the incubation period before treatment was 10 d but not when the period was 42 d.     

Role of Benzoxazinones in Cereals

Summary

Heterocyclic 1,4-benzoxazin-3-ones and related benzox-azolinones are important natural products of the cereal crops maize, wheat and rye. Much research has focused on the role of these compounds as defensive agents against plant diseases and pests. Studies of a wide variety of biological effects on herbivores and nematodes, plant pathogenic fungi and bacteria are reviewed in this article. Phytotoxic activity of the compounds is also considered with respect to allelopathic interaction with higher plants. Recent investigations of molecular aspects of interactions of cyclic hydroxamic acids and related benzoxazo-linones with acceptor organisms have demonstrated different effective detoxification strategies and tolerance mechanisms. This research has greatly advanced our knowledge about the multiple roles that these allelochemicals play in ecological systems.     

Potential of dry fractionation of wheat bran for the development of food ingredients,part I: Influence of ultra-fine grinding

Wheat bran is an undervalued by-product of white flour and has great nutritional potential due to its high content in fibres and bioactive compounds. Micronized bran could be used as a food ingredient to improve the nutritional potential of cereal products, or be used as a starting material for other processes (bioactive compound extraction or bran fractionation). The aim of this work was to find a way to efficiently decrease the particle size of bran. The influence of the grinding temperature (ambient or cryogenic grinding) on the granulometric distribution of particles, their composition, and their microstructure was studied, at lab-scale and pilot-scale. It showed that the intrinsic characteristics of bran (glass transition within intermediate layers at −46 °C) had more influence on its grinding behaviour than the type of grinding device used: the particles size distributions obtained after grinding at lab-scale and pilot-scale were very similar. At both scales, the granulometric curves were narrow for cryogenic grinding, while for ambient grinding they were spread over the whole particle size range. Ultrafine particles were obtained in both ambient and cryogenic conditions. Negative temperatures, by increasing the material’s brittleness, favoured a fast fragmentation of bran: one step of cryogenic grinding allowed a median particle size of nearly 50 μm to be reached, whereas three successive steps of ambient grinding were needed for the same result. On the other hand, ambient temperature favoured the dissociation of the different constituent layers of wheat bran, and produced less composite particles than cryogenic grinding.     

Multiple use of plants: Studies on selenium incorporation in some agricultural species for the production of organic selenium compounds

The technique of spraying plants with inorganic forms of selenium can be employed for phytochemical production of organic selenium compounds. Fractionation of the plant material makes it possible to produce a highly concentrated and well defined selenium supplement with potential use in animal and human nutrition. The fractionation also gives opportunities to combine production of organic selenium compounds with other products, for example plant fibres. Multiple use of plants can contribute to a more efficient utilization of land area (in comparison to monocultures solely adapted to food production). It also gives the opportunity to develop systems suitable for long term fixation of carbon, as long as the plant material is not reoxidised to carbon dioxide. Plant fibres could provide raw material for the production of paper or building materials in combination with the production of organic selenium compounds preferentially accumulated in another fraction of the processed plant.     

Biological factors influencing the transmission of potato leafroll virus by different aphid species

Summary Macrosiphum euphorbiae, collected in the field from potato plants infected with potato leafroll virus (PLRV), transmitted the virus to fewer potato plants in a field trial than did laboratory-rearedMyzus persicae. In the laboratory,M. persicae was the only efficient vector of PLRV fromPhysalis floridana seedlings, potato sprouts or excised leaves toP. floridana. Two clones ofM. euphorbiae and one clone ofAulacorthum solani transmitted PLRV from infected potato plants toNicotiana clevelandii as effeciently asM. persicae but a clone ofAphis gossypii was an inefficient PLRV vector. An isolate of PLRV, whichM. persicae transmitted inefficiently from potato toN. clevelandii, was also transmitted inefficiently byM. euphorbiae andA. solani.