澳洲坚果引种栽培研究

[目的]引进适宜贵州气候特点的澳洲坚果优良品种。[方法]2007年从中国热带农业科学院南亚热带作物研究所引进4个澳洲坚果优良品种在贵州望谟县和贞丰县试种,2010年4个品种零星开花结果,分析各品种的品种特性。[结果]从综合性状看,在贵州南亚热区表现最好的品种是Own Choice（O.C）,4年生树株高329 cm,茎围23 cm,树冠315 cm,单株产量平均1.52 kg;其次是Pahala（788）,4年生树株高363 cm,茎围24.8 cm,树冠328 cm,单株产量平均0.53 kg。[结论]研究结果为澳洲坚果的引种栽培提供了参考。     

Weibull分布函数和Rayleigh密度函数在组建褐飞虱种群预测模型中的应用

 本文研究应用 Weibull 分布函数Y=100×[1-exp(-X/b)^c]描述褐飞虱雌虫产卵量的时间序列分布、若虫进龄百分率和卵的累计孵化率,用 Rayleigh 密度函数Y=A·X·exp(-X²/2H²)描述各龄若虫存活率。然后将这些参数组建成褐飞虱田间种群数量预测模型,经用历史资料验证,结果模拟值与实查值基本一致。     

马铃薯优化再生系统的建立

本试验研究了六种培养基系统对马铃薯东农３０３，Ｆａｖｏｒｉｔａ和极早三个品种来源的不同外植体的愈伤组织诱导和植株再生的影响，筛选出了适合植株再生的最佳外植体、最佳外植体大小及最佳培养基系统。适合植株再生的最佳外植体为叶片；最佳外植体大小为叶片０．５ｃｍ２、茎０．５ｃｍ、块茎０．２５ｃｍ２×０．３ｃｍ，适合于茎、块茎及叶的有效培养基系统分别为：①ＭＳ＋３ｍｇ·Ｌ-１ＢＡ＋０．０１ｍｇ·Ｌ-１ＮＡＡ（ｐｈ５．６）４周ＭＳ＋０．３ｍｇ·Ｌ-１ＧＡ３（ｏＨ５．６）；②ＭＳ＋１．７５ｍｇ·Ｌ-１ＺＴ＋０．８７ｍｇ·Ｌ-１ＩＡＡ（ｐＨ５．８）；③ＭＳ＋２．２５ｍｇ·Ｌ-１ＢＡ＋０．１８６ｍｇ·Ｌ-１ＮＡＡ（ｐＨ５．８）２周ＭＳ＋５ｍｇ·Ｌ-１ＧＡ３＋２．２５ｍｇ·Ｌ-１ＢＡ（ｐｈ５．８）。     

双亚10号亚麻新品种的选育

双亚10号是以(78-97×奥尔沙)×(85-1832×FR2)复合杂交育成的,具有高纤、优质、抗旱、抗倒伏和抗病优点.区域试验每公顷原茎、长纤维和种子产量分别为6068.7kg、975.1kg和741.9kg,分别比对照品种黑亚7号增产6.6%、24.5%和18.4%.生产试验每公顷原茎、长纤维和种子产量分别为5326.1kg、861.0kg和449.1kg,分别比对照品种黑亚11号增产8.5%、23.7%和10.9%.长麻率20.6%、全麻率29.9%,纤维强度26.7kg.     

多环芳烃的吸收累积对茶叶化学成分的影响

通过水培试验,研究分析了两种多环芳烃(PAHs)物质(菲和芘)在茶树体内的吸收、累积和转移,以及对茶叶体内几种有效化学成分的影响。结果表明,当营养液中菲和芘处理浓度为1.00mg/L和0.10mg/L时,茶树须根中菲和芘浓度最高,为2.21×10-1mg/g干重(DW)和1.07×10-1mg/gDW;菲在茶树茎中最高含量7.00×10-3mg/gDW,叶片中含量为3.10×10-4mg/g鲜重(FW),芘在茎和叶中则均未检测到。菲和芘对茶树乌牛早品种叶片内化学成分影响显著,菲和芘单独处理后,茶树叶片内儿茶素总量最高分别上升35.13%和46.56%;菲和芘的混合处理中儿茶素总量最高增加48.23%,多酚和咖啡碱含量也有明显升高。然而,菲和芘处理后茶树叶片内氨基酸含量下降。     

珍稀果树——黄皮

黄皮[Clausena lansium(lour.)Sk-eels],又名黄弹,系芸香科黄皮属常绿小乔木果树.原产我国华南,现亚洲热带地区有栽培.我国华南地区的广东、广西栽培面积较大,品种多而优,被称为“岭南佳果”之一.我省闽南地区有零星栽植,闽南人誉为珍稀果树.我所于七十年代,先后从广东、广西引入酸黄皮和甜黄皮等两个品种进行试种,至今已近十年.试种结果表明,黄皮果树适应性较强,生长和开花结果正常.八龄果树高达4米,冠幅3.5×3.8米,围茎粗度50厘米.实生树3至4年开花结果,嫁接树2至3年就可投产,单株可收获果实3.5—6公斤,6年生单株产果达15公斤.     

HPLC法测定菌株S15发酵液中Zygosporin D的含量

用HPLC法测定菌株S 15发酵液中Zygosporin D(乙酰基细胞松弛素D)的含量。色谱条件为：Kromasil -C18柱(4.6 mm×150 mm, 5 m)，柱温25 ℃，流动相乙腈-水(体积比40:60)，流速(1.0 mL/min)，检测波长(216 nm)。标准曲线回归方程：Y＝0.409 03X＋1.547 7，r＝0.999 8，Zygosporin D回收率为100.5%。实验证明该方法稳定可靠，精密度高，重现性好，简单可行，适用于Zygosporin D的分析检测。     

不同种植模式对巴西香蕉生长及产量的影响

比较不同种植模式对巴西香蕉生长及产量的影响。结果表明：在不同种植模式下,茎高、茎围、叶长、叶宽的生长规律相似;各处理的茎围、叶宽、青叶数、果指数、抽蕾率、果穗轴尾部直径之间无显著差异;茎高、叶长、吸芽数、果指长度与果指围度、果穗轴头部直径之间除了D2(矩形单行植,株行距为2.0 m×3.0 m,种植密度为1 666株/hm2)与D3[矩形宽窄行植,株行距为1.5 m×(3.0＋1.0)m,种植密度为3 333株/hm2]有显著差异外,其他无显著差异,而且茎围、青叶数、吸芽数、果指数、果指长度与果指围度、果穗轴头部与尾部直径均随种植密度的增加而减少;现蕾期与果生育期随种植密度的增加而有所延长且收获期较分散;单果重、单株产量随种植密度的增加而减少,单位面积产量则随种植密度的增加而增加,差异极显著。     

马铃薯同薯23号的品种特征与高效栽培技术

马铃薯品种同薯23号选育自8029-[S2-26-13-(3)]×NS 78-4。该品种中晚熟,具有高产稳产,抗X、Y病毒病,抗晚疫病,结薯集中,薯形好等特征。本文介绍了其在实践当中的高效栽培技术,包括整地、合理施肥、种薯处理、切薯处理、播种方法、田间管理、病虫害防治、适时收获等内容,为该品种的大面积推广起到了技术指导作用。     

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.