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1.
杂交稻制种喷施“九二○”增产机理及其衡量指标的探讨 总被引：1，自引：0，他引：1
改善穗层结构和提高柱头外露率是喷施“九二○”的主要增产机理。包颈长，株高，柱头外露率反映了母本异交性能的优劣，是衡量“九二○”喷施效果的最好指标。汕Ａ的最佳异交态势为：包颈长０～１ｃｍ，株高８５～９５ｃｍ，柱头外露率５０％以上。 相似文献
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本文以Ａ１，Ａ２等五个红麻品种为材料，测试麻茎，骨的密度（比重），茎节间长，单位长度麻骨重，麻株重心，皮骨比值，叶柄与茎夹角，髓腔径和根重与麻株倒伏的关系。结果表明：Ａ１的麻骨密度０．１５１８ｇ／ｃｍ＾３最大，其次Ａ３为０．１４７３ｇ／ｃｍ＾３，分别比Ａ５高２１．７１％，１９．３４％，茎和骨密度与品种倒伏显著正相关（ｒ＝０．９３１，０．９００）。Ａ２茎节间距平均４．５６１厘米最短；叶夹角小，平均比 相似文献
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用ＧＡ、ＩＡＡ和Ｋｎ等植物激素为克服花生种间杂交（栽培种×Ａｒａｃｈｉｓｇｌａｂｒａｔａ）不亲和性，在不同发育时期以不同浓度进行处理。结果表明，ＧＡ处理平均出针率１４．２％－３３．３％，果针伸长８．７ｃｍ，子房膨大率７５．０％；ＩＡＡ处理子房膨大率８７．２％；Ｋｎ处理促进荚果形成，成荚率１２．５％－６５．１％。 相似文献
4.
本文以Ａ１、Ａ２等五个红麻品种为材料，测试麻茎、骨的密度（比重），茎节间长，单位长度麻骨重，麻株重心，皮骨比值，叶柄与茎夹角，髓腔径和根重与麻株倒伏的关系。结果表明：Ａ１的麻骨密度０．１５１８ｇ／ｃｍ３最大，其次Ａ３为０．１４７３ｇ／ｃｍ３，分别比Ａ５高２１．７１％、１９．３４％，茎和骨密度与品种倒伏显著正相关（ｒ＝０．９３１＊＊、０．９００＊＊）。Ａ２茎节间距平均４．５６１厘米最短；叶夹角小，平均比Ａ５短１．８７６厘米，小１０．３９度，根总重比Ａ５高３４．３５％。Ａ５皮骨比值（０．７７３）最大。茎节长、叶夹角、皮骨比值与麻株倒伏呈正相关（ｒ＝０．９４３＊＊、０．９８０＊＊、０．８４０＊）。根重与麻株倒伏是显著负相关。髓腔径品种间差异较大，腔茎比与麻株倒伏相关但不显著。 相似文献
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外施脱落酸和赤霉素对海南岛落叶树木韧皮部的作用 总被引：5，自引：3，他引：2
将脱落酸（０．２％ＡＢＡ和１％ＡＢＡ羊毛脂）和赤霉素（０．５％ＧＡ３和１％ＧＡ３羊毛脂）涂到树干树皮的刮皮伤口上，经过８ｄ后用光学显微镜技术观察堵塞筛管的固定胶胝体在韧皮部中形成的位置，以确定有功能韧皮部的厚度。对于无叶期筛管破坏型的树种苦楝树（Ｍｅｌｉａ ａｚｅｄａｒａｃｈ Ｌ．），在生长季开始时期之后施用ＡＢＡ，能使有功能韧皮部大量减少，但在生长季开始时期施用，对韧皮部几乎没有作用；在生长季晚 相似文献
7.
红麻株高（ｈ，ｃｍ）和基部离地面１０．０－１２．５ｃｍ部位的茎粗（ｄ，ｃｍ）是预测单株产量（ｙ，ｇ）可靠的性状。发现了ｙ＝０．１（ｄ／２）~２ｈ可估计单株干皮产量，ｙ＝０．０５６（ｄ／２）~２ｈ可估计单株纤维产量。该式简单易行，快速而较准确，可对不同类型品种各生长时期的单株和群体产量进行预测。在田间只要测量株高和茎粗，查看根据本公式编制的一本“红麻产量预测查对表”，便知其单株的干皮和纤维产量。 相似文献
8.
红麻株高（ｈ，ｃｍ）和基部离地面１０．０－１２．５ｃｍ部位的茎粗（ｄ，ｃｍ）是预测单株产量（ｙ，ｇ）可靠的性状。发现了ｙ＝０．１（ｄ／２）＾２ｈ可估计单株干皮产量，ｙ＝０．０５６（ｄ／２）＾２ｈ可估计单株纤维产量。该式简单易行，快速而较准确，可对不同类型品种各生长时期的单株和群体产量进行预测。在田间只要测量株高和茎粗，查看根据本公式编制的一本“红麻产量预测查对表”，便知其单株的干皮和纤维产量。 相似文献
9.
“九二０”在杂交水稻繁殖制种中，对提高异交结实率起着核心作用。但随着制种面积扩大和亩用量逐年增加，“九二０”供求矛盾突出，几年来一直货源紧张、价格猛涨，为了节省和充分发挥“九二０”功能，全国不少科研单位已研制出了“九二０”增效剂。为此，我地按省种子公司意图，在东山头珍汕９７Ａ繁殖基地作了应用比较试验。１材料与方法１．１材料（１）“九二０”。作对照和配用在各增效剂中的“九二０”，均系上海溶剂厂生产。（２）浙农大增效剂。系浙江农业大学和衢县种子公司联合研制，为’型浓缩水溶性乳剂，每瓶装３５ｍｌ（简称… 相似文献
10.
四川棉花核不育杂交种利用研究进展与前景 总被引：2，自引：2，他引：2
２０多年来，采用“两系法”配制陆地棉品种间杂交种，先后选育出“洞Ａ”、“７５１Ａ”、“４７３Ａ”、“ＭＡ”核不育系，与此同时，研究建立了与核不育相适应的良繁体系及种子生产体系。先后筛选培育出了川杂１、２、３、４、６号，内杂１号、杂交早熟系列杂交种，平均增产皮棉１７６．５５ｋｇ／ｈｍ２，累计推广面积５０万公顷。近年来，又从“洞Ａ”系中，培育成功一种核不育完全保持系即ＭＢ系，利用ＭＢ系同核不育系（ｍｃ１ｍｃ１）杂交生产一种新的不育系即ＭＡ系（ｍｃ１ｍｃ１），其后代不育株率达１００％，不育度达９５％～１００％。采用“二级法”实现了核不育“三系”配套。标志着利用核不育系配制杂交种应用于生产的又一次重大突破，将有力地推动四川杂交棉研究和应用的发展。 相似文献
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《Journal of Crop Improvement》2013,27(2):81-114
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. 相似文献
13.
Novel food and non-food uses for sorghum and millets 总被引：4，自引：3，他引：4
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. 相似文献
14.
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. 相似文献
15.
Yanhua Lu Chongwei Zhang Peter Bucheli Dongzhi Wei 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):55-63
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. 相似文献
16.
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. 相似文献
17.
《Journal of Crop Improvement》2013,27(2):379-400
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. 相似文献
18.
Potential of dry fractionation of wheat bran for the development of food ingredients,part I: Influence of ultra-fine grinding 总被引：1，自引：0，他引：1
Youna Hemery Marc Chaurand Ulla Holopainen Anna-Maija Lampi Pekka Lehtinen Vieno Piironen Abdelkrim Sadoudi Xavier Rouau 《Journal of Cereal Science》2011
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. 相似文献
19.
Multiple use of plants: Studies on selenium incorporation in some agricultural species for the production of organic selenium compounds 总被引：3，自引：0，他引：3
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. 相似文献
20.
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. 相似文献