普洱市小粒咖啡病虫害种类调查分析

对云南省普洱市小粒咖啡主要栽种区病虫害及荫蔽树种类、杂草和荫蔽树与咖啡病虫害的关系进行调查研究。结果发现普洱市小粒咖啡害虫有13种,病害有7种,常用荫蔽树有17种。文中还分析杂草和荫蔽树与咖啡病虫害关系,就普洱市咖农的管理技术提出建议。     

海南岛咖啡病虫害的调查报告

1987～1989年对海南岛6个县12个场、乡41个种植点的咖啡小粒种、中粒种、大粒种共10多个变种的病虫害进行调查,并采集标本,共鉴定出害虫48种,隶属于7目32科;病害22种,分别属于6大类型。     

云南小粒种咖啡荫蔽栽培研究

云南小粒种咖啡荫蔽栽培有利于咖啡营养生长和生殖生长的平衡,能有效控制主要病虫和草害的发生,有利于咖啡丰产、稳产,提高品质和降低生产成本;咖啡与热带经济作物、果树间作,改善了生态环境,提高了土地利用率和单位土地面积的经济效益：是发展云南小粒种咖啡的最好方式。     

海南省小粒种咖啡炭疽病农药筛选及综合防治

报道了海南省小粒种咖啡炭疽病大田农药筛选和综合防治结果。波尔多液、灭病威和甲基托布津防效较高，且相对稳定。采取加强栽培管理和化学防治相结合的综合措施防病，可以明显减轻小粒种咖啡炭疽病的为害，产量也有较大幅度提高。     

小粒咖啡不同海拔土壤肥力现状及变化特征

全国第二次土壤普查迄今30年,小粒咖啡的土壤肥力不断更新变化,为实现土地资源的有效利用并促进咖啡产业的可持续发展,探寻小粒咖啡的土壤肥力现状和变化特征尤为重要。2015—2018年间对小粒咖啡6个主产区采集的大量土壤数据进行分析,研究咖啡地土壤肥力现状,并与第二次土壤普查数据相对比,得出咖啡土壤肥力的变化特征及原因。目前,小粒咖啡土壤pH、有机质、碱解氮、有效磷和速效钾的平均值分别为5.53、32.68 g/kg、128.77 mg/kg、18.01 mg/kg和138.31 mg/kg,主要分布范围分别为4.5～5.5、>40 g/kg、120～150 mg/kg、10～20 mg/kg和100～150 mg/kg。小粒咖啡土壤肥力在不同海拔高度的分布均存在显著差异,pH和碱解氮含量随海拔高度增加而降低,有机质和有效磷含量随海拔高度增加而增加,速效钾含量随海拔高度的增加呈先增加后降低。与第二次土壤普查相比,目前小粒咖啡土壤呈酸化趋势,有机质、碱解氮和速效钾含量明显降低,而有效磷含量显著提高。宜耕区长期频繁耕作、大量施用化学肥料,小粒咖啡土壤肥力变化显著。建议小粒咖啡主产区应控制磷肥施用量,推进咖啡秸秆、果皮发酵还田的力度,加快小粒咖啡土壤肥力的提高并达到养分供需平衡。     

云南芒果病虫害调查研究

为摸清云南省芒果病虫害的种类及其发生危害情况,进而为防治云南省芒果病虫害提供依据,为芒果产业的快速发展提供保障,于2008～2010年期间,根据芒果的种植分布、病虫害发生特点,采用定点调查、走访、询问和全面普查相结合的方法,对云南省芒果主产区病虫害分布、危害及种类进行了调查,共鉴定出云南省芒果病虫害94种,其中病害23种,害虫71种。     

云南河口县特色优势小粒种咖啡产业的培育和发展

回顾云南河口县特色小粒种咖啡产业的培育和发展历程,对河口县发展特色小粒种咖啡产业的优、劣势进行分析,同时指出发展中存在的主要问题,并提出进一步发展的具体建议。     

中国小粒种咖啡高海拔种植研究

对云南小粒种咖啡高海拔种植适应性进行分析和评价,进一步明确在适宜的范围内,海拔越高,杯品质量越好。高海拔是生产精品咖啡的重要条件,卡蒂姆咖啡在高海拔种植杯品质量显著提高。发展高海拔咖啡生产,可提高咖啡生产经营效益,对促进国内小粒种咖啡生产持续发展具有现实意义。     

纬度对云南咖啡质量的影响研究

云南是中国仅有的小粒种咖啡生产省份,也是世界上咖啡种植纬度最北的地区(世界其它咖啡种植最北的纬度为22°N,而云南为25.5°N),具有独特的地理和气候类型。在这次调查研究中,笔者从小粒种咖啡主要种植区普洱、德宏和保山搜集了52个样品,在德国柏林由一个专业杯品测试小组对其进行测评。在对比相同海拔下(大约1 000 m)的不同Catimor7963样品时,发现纬度与杯品质量之间存在正相关。这说明与相同海拔低纬度地区相比,高纬度地区的咖啡豆具有较好的杯品质量。因此纬度可作为杯品质量的一个地理因素。     

滇南、滇东南芒果病虫害种类调查研究

采用定点调查与普查相结合的方法,对滇南、滇东南芒果生产区芒果病虫害分布、危害情况及种类进行了调查,结果鉴定出危害滇南、滇东南芒果生产的病害25种,虫害61种。同时对滇南、滇东南芒果生产的干热区和湿热区病虫害的分布以及差异作了分析。调查结果对于生产上科学制定防治措施,保障滇南、滇东南芒果种植业的持续健康发展具有重要意义。     

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.