Effect of pre-storage application of different organic and inorganic salts on stored potato quality

Summary The application of salts including aluminium chloride, potassium sorbate, sodium benzoate and sodium metabisulfite has been shown to control diseases of stored potato tubers. In order to integrate salt application in the disease control strategies, it is imperative to evaluate their effect on the quality of stored tubers. The effect of salt application either alone (0.05 M and 0.2 M) or in combination on quality attributes of tubers of two cultivars (Norland and Shepody) stored at 4 °C for up to 6 months was evaluated. Higher weight losses were generally observed in tubers treated with aluminium chloride and sodium metabisulfite after 6 months of storage, while the organic salts, sodium benzoate and potassium sorbate, exhibited weight losses comparable to that of the control tubers. Both organic salts at a concentration of 0.2 M decreased sprout growth on Shepody cultivar tubers. Sodium benzoate was shown to increase the sugar content of the stored tubers.     

The value of catch crops and organic manures for spring barley in organic arable farming

The effect of nitrogen (N) supply and weeds on grain yield of spring barley was investigated from 1997 to 2004 in an organic farming crop rotation experiment in Denmark on three different soil types varying from coarse sand to sandy loam. Two experimental factors were included in the experiment in a factorial design: (1) catch crop (with and without), and (2) manure (with and without). The crop rotation included grass-clover as a green manure crop. Animal manure was applied as slurry in rates corresponding to 40% of the N demand of the cereal crops.

Application of 50 kg NH₄-N ha⁻¹ in manure (slurry) increased average barley grain DM yield by 1.0–1.3 Mg DM ha⁻¹, whereas the use of catch crops (primarily perennial ryegrass) increased grain DM yield by 0.2–0.4 Mg DM ha⁻¹ with the smallest effect on the loamy sand and sandy loam soils and the greatest effect on the coarse sandy soil. Model estimations showed that the average yield reduction from weeds varied from 0.2 to 0.4 Mg DM ha⁻¹ depending on weed species and density. The yield effects of N supply were more predictable and less variable than the effects of weed infestation. The infestation level of leaf diseases was low and not a significant source of yield variation.

The apparent recovery efficiency of N in grains (N use efficiency, NUE) from NH₄-N in applied manure varied from 29 to 38%. The NUE of above-ground N in catch crops sampled in November prior to the spring barley varied from 16 to 52% with the largest value on the coarse sandy soil and the smallest value on the sandy loam soil. A comparison of grain yield levels obtained at the different locations with changes in soil organic matter indicated a NUE of 21–26% for soil N mineralisation, which is smaller than that for the mineral N applied in manure. However, this estimate is uncertain and further studies are needed to quantify differences in NUE from various sources of N.

The proportion of perennial weeds in total biomass increased during the experiment, particularly in treatments without manure application. The results show that manure application is a key factor in maintaining good crop yields in arable organic farming on sandy soils, and in securing crops that are sufficiently competitive against perennial weeds.     

有机叶面肥的施用对铁观音茶品质的影响

以＂红芽铁观音＂品种为材料,研究叶面肥（天达2116细胞膜稳态剂、基因活化剂、6%核苷酸水剂、植物动力2003、6%甲壳素水剂）的喷施对铁观音茶品质的影响。结果表明：天达2116细胞膜稳态剂、基因活化剂对促进茶树腋芽分化和叶片增厚具有较好的效果,茶青品质显著提高,值得推广使用。     

关于"有机茶、无公害茶、生态茶"的思考

最近一、二年一些茶区开发"有机茶、无公害茶、生态茶"炒得很热乎,各地提法不尽相同,有的叫有机茶,有的叫无公害茶,有的叫生态茶,也有叫无公害(有机)茶,无公害(放心)茶,无公害生态茶,绿色食品茶等,"词儿"很多,弄也弄不灵清,可以肯定提倡开发这些产品的部门是清楚的,都有自己特定的要求和定义,但是,茶区基层干部和茶农不一定都很清楚,有茶农反映:到底听谁好?到底要我们开发什么茶,建立什么样的生产基地?有没有销路和效益,这是茶农最关心的问题.现在,这些新名称的成品茶已经陆续上市,反映在茶叶包装上、媒体广告上,可以这样说,这些有机茶,无公害茶,生态茶,绿色食品茶等,目前还没有可以用简单直观的办法去区别与常规茶的"不同"之处,只能凭"标志"的感觉去选购,有的消费者又不放心,怕上当受骗,无所适从.     

近红外光谱技术在农产品品质检测中的应用

近红外光谱技术是一种新型的无损检测技术,在许多领域都得到了很好的应用。本文从农产品中各种物质成分含量预测、分类鉴别、腐烂鉴别、实时监测几个方面综述了近红外光谱技术在农产品品质检测上的应用,并对其在仪器硬件的研究和开发、化学计量学方法的探索与研究以及快速在线检测方法的研究等方面的发展趋势进行了展望。     

新植蔗施鱼粉有机-无机复混肥对宿根蔗产量品质和土壤肥力变化的影响

本试验在大田生产条件下研究2004年春植蔗施用鱼粉有机-无机复混肥后,对2005年宿根蔗的产量及品质影响。结果表明:鱼粉有机-无机复混肥对甘蔗生长的长效性影响比较明显,土壤酸碱度、有机质含量及N、P和K的含量变化较其他的几个处理相比有较强的效应。每666.7m2的蔗茎产量和含糖量处理1和处理2均比其他处理高,也表明有机肥对土壤肥力提高有良好的影响。     

巴戟天的生物学特性和繁殖方式对其品质的影响

本研究以种子繁殖、扦插繁殖和组培苗繁殖3种不同方式种植巴戟天,观察栽培期间的生物学特性并测定比较其品质和成活率。结果表明,种植5年后收获时,扦插繁殖的巴戟天根直径、干重、蒽醌类化合物含量较高;组堵苗繁殖的成活率较高。     

Reproductive performance of rabbits on organic and inorganic leys

A comparison was made of the reproductive performance of rabbits on organic and inorganic leys. The fecundity of rabbits on inorganic leys was greater but this advantage was to some extent counteracted by a lower viability. The maternal behaviour was superior in rabbits on organic leys but fertility was lower. The overall reproductive performance of New Zealand white rabbits on inorganic leys was superior, but this trend was reversed for Dutch rabbits. Milk-production was generally better in rabbits on organic leys but the growth rates of the offspring varied more or less evenly between organic and inorganic leys. The data do not support the assumption that organic methods of farmingper se necessarily produce food of a superior nutritional quality.     

有机茶生产条件和质量安全主要控制点

有机茶是在原料生产过程中遵循自然规律和生态学原理，采取有益于生态和环境的可持续发展的农业技术，不使用合成的农药、肥料及生长调节剂等物质，在加工过程中不使用合成的食品添加剂，并经过有关认证机构认证的茶叶。它不受污染，是茶叶中最卫生最安全的产品。随着我国人民生活水平的提高和我国加入WT0之后，有机茶越来越受到国内外茶叶爱好者的青睐。     

Occurrence and characterization of fungi and oomycetes transmitted via potting mixtures and organic manures

A study was conducted to investigate the most common fungal and oomycete pathogens introduced into farms in Oman via potting mixtures and organic manures. A total of 37 commercial types of potting mixtures (2 local and 35 imported from overseas), 4 commercial types of organic manures and 11 non-commercial types of organic manures were included in the study. Identification of the isolated species was based on morphological characteristics, except for the most common species which were further identified using sequences of the internal transcribed spacer region of the ribosomal DNA (ITS rDNA). Fusarium spp. (14%), Pythium aphanidermatum (3%), Alternaria spp. (5%), Helminthosporium spp. (5%) and Cladosporium spp. (3%) were recovered at different frequencies from samples of potting mixtures. Fusarium solani (40%) and Fusarium equiseti (47%) were recovered at high frequencies from samples of organic manures. Isolations from organic manures also yielded Pythium periplocum (7%), Rhizoctonia solani (7%), Fusarium lichenicola (7%), Helminthosporium spp. (27%) and Alternaria spp. (27%). Trichoderma spp., Penicillium spp., Aspergillus spp. and Rhizopus spp. were found to be common in samples of potting mixtures and organic manures. Investigating sensitivity to hymexazol among 9 isolates of F. equiseti and 13 isolates of F. solani revealed variations among different isolates. The EC₅₀ values ranged from 1 to over 1200 (avg. 192 μg ml⁻¹) for F. equiseti isolates and from 135 to 789 (avg. 324 μg ml⁻¹) for F. solani isolates, indicating presence of resistance to this important fungicide among some Fusarium isolates. This appears to be the first report of contamination with R. solani, P. periplocum, F. solani, F. equiseti and F. lichenicola of organic manures. This study appears to report for the first time F. lichenicola in Oman and appears to be the first report of occurrence of resistance to hymexazol among F. equiseti and F. solani isolates.     

Effects of processing on protein nutritive quality of coconut Cocos nucifera products

Pared, comminuted and blanched coconut meat was freeze-dried at25 ^°C for 24 hours and pulverized. Whole coconut meal wassolvent extracted with n-hexane to yield a defatted meal while full-fatcoconut protein concentrate (FFC-PC) containing 27.60% protein wasprepared by alkali extraction of undefatted meal followed by isoelectricprecipitation. Defatted coconut meal had a significantly (p 0.05)lower crude fat but higher protein content than whole coconut meal.Similarly, FFC-PC had a significantly (p 0.05) higher proteinbut lower carbohydrate content than whole coconut meal and defattedcoconut meal. Whole coconut meal, defatted coconut meal and FFC-PChad PERs of 1.98, 2.18 and 2.48 respectively, with NPRs of 2.86, 3.28and 3.92, respectively. Protein digestibility values of 88.75%, 89.30%and 94.02% were obtained for whole coconut meal, defatted coconutmeal and full-fat coconut protein concentrate, respectively. Growthresponse of animals showed that FPC-PC was superior to all other testdiets.     

Successive annual applications of organic manures for cut grass: short-term observations on utilization of manure nitrogen

Abstract The recovery of nitrogen (N) from, and the fertilizer‐N value of, low dry‐matter (DM) cattle slurry and farm yard manure (FYM), applied annually to perennial ryegrass swards grown at two sites, on sandy loam and shallow calcareous silty clay loam soils, were studied over a 4‐year period. Slurry or FYM, applied at target rates of either 150 kg N ha^?1 or 300 kg N ha^?1 in either October, February or May/June, in combination with 150 kg N ha^?1 inorganic fertilizer‐N (applied as split dressings before the first and second grass cut), were compared with a set of inorganic fertilizer‐N response treatments. DM yield, N offtake, apparent manure‐N recovery (in herbage) and manure‐N efficiency (compared with inorganic fertilizer‐N) were determined at two silage cuts each summer. Soil mineral nitrogen (SMN) measurements in autumn and spring were used to assess potential N leaching loss over winter and to quantify available N residues in the soil in spring. Apparent manure‐N recovery and manure‐N efficiency were usually greater from slurry applications in February than from those in October, but the timing of the application of FYM had a much smaller effect, compared with the timings of the application of slurry, on the utilization of N from manure by grass. Spring assessment of SMN was useful in quantifying available N residues from October slurry applications. Manure‐N recovery for all application timings was, on average, higher from the sandy loam than the shallow calcareous clay loam. The application of slurry to grass in early spring, at a rate of 150 kg total N ha^?1, with the addition of a supplementary 50 kg inorganic fertilizer‐N ha^?1, was the most suitable strategy for utilizing slurry‐N effectively and for supplying the N requirement for first‐cut silage.     

Repeated application of anaerobic digestate,undigested cattle slurry and inorganic fertilizer N: Impacts on pasture yield and quality

The growth of on‐farm anaerobic digestion (AD) has generated significant quantities of digestate for use as a soil amendment. However, relative to other organic and inorganic fertilizers, only limited field trial data exist on the effect of repeated applications of digestate to temperate grasslands. Here, we compare yields and grass quality (protein and digestibility) from a field trial of a mixed pasture ley (ryegrass and clover), following the application of five different fertilizer types (liquid digestate generated from anaerobically digested slurry, dry fibre digestate, undigested slurry, ammonium nitrate and an NPK compound fertilizer) in comparison with a no‐fertilizer control. Application rates were normalized in terms of nitrogen (N) and were added as a split dose, with 100 kg N/ha added prior to the first harvest and an additional 50 kg N/ha supplied after the first harvest, every year for 3 years. Overall, our results showed that applying both forms of digestate or undigested slurry gave grass yields that matched those obtained with one compound inorganic fertilizer, and better than those from a straight N inorganic fertilizer. No differences were found with regard to digestibility or sward N‐content (hence calculated protein) between any treatments. Although the trial was conducted at only one site, the results indicate that inorganic fertilizers can potentially be replaced by digestate without compromising grassland productivity.     

农产品及食品黄曲霉毒素污染研究

黄曲霉毒素主要由黄曲霉等产毒真菌产生,属生物源危害物,是毒性极强的一类真菌毒素,历史上因食用黄曲霉毒素污染产品造成过多次人及家养动物群体中毒死亡事件。黄曲霉毒素通过污染农产品与动物饲料进入食物链,严重威胁全球食品安全与人类健康。为了减少黄曲霉毒素污染危害,非常有必要掌握黄曲霉毒素污染农产品及食品主要种类。因此,本文通过研究国内外相关文献报道,较为全面地总结了近年来黄曲霉毒素污染农产品及其制品的主要种类,包括：谷物及其制品、调味品、饲料等12个类别,共计143种产品。通过归纳总结黄曲霉毒素污染产品种类,可以为农产品及食品黄曲霉毒素污染防治研究提供重要科学依据,对保障消费安全和产业健康发展具有重要指导意义。     

控释尿素与尿素配施对油菜籽产量、经济效益和土壤无机氮含量的影响

2009-2010年在我国油菜主产区采用多点田间试验研究了控释尿素(controlled-release urea,CRU)和普通尿素(Urea)配合施用对油菜籽产量、氮肥利用率、土壤无机氮含量及经济效益的影响,以期为两者在油菜上的配合施用提供理论依据.结果表明,在所有试验点两者配施(60％ CRU+40％ Urea)比一次性基施等氮量普通尿素(100％ Urea)增产菜籽11.4％ ～ 12.9％,与一次性基施等氮量控释尿素(100％ CRU)的产量无显著差异.苗期的干物质量和氮积累量表现相同规律,配施处理与100％ Urea处理无显著差异,与100％ CRU处理相比,除浠水试验点分别增加10.59％ ～ 50.58％和10.40％ ～ 28.57％外,成熟期配施与100％ CRU处理无显著差异,但分别比100％ Urea处理增加5.4％～20.9％和8.7％ ～18.8％.配施的氮肥利用率比100％ Urea处理提高7.6个百分点,可以达到100％ CRU的效果.油菜收获后,配施处理的耕层土壤无机氮含量高于100％ Urea处理5.0％～44.2％,低于100％ CRU处理19.6％ ～ 38.8％.经济效益分析结果显示,配施处理比100％ Urea增收488.9～1 040.2元/hm2,比100％ CRU增收205.3 ～ 599.0元/hm2.     

硒、锌对甘蓝型油菜产量和营养品质的影响

采用土培试验,以甘蓝型油菜为供试作物,研究了陕西渭北旱塬低硒、低锌土壤上,硒、锌对甘蓝型油菜产量和营养品质的影响。试验结果表明,硒对油菜生物量和产量没有明显的影响。锌或硒锌配施对油菜生物量和产量有增加趋势;施硒促进油菜籽对钾、硒元素的吸收累积,而在一定程度上抑制了磷、硫、钙和镁元素的吸收。施锌促进油菜对钾、钙、铁、锰、铜、锌、硼的吸收累积,而对氮、硫的吸收有抑制作用。硒锌配合施用有利于促进油菜对硒、锌的吸收累积,而对铁的吸收有一定的抑制作用;施硒对油菜籽含油量、芥酸有增加趋势,对蛋白质、硫甙含量有降低趋势。施锌对油菜籽含油量有增加趋势,对蛋白质、硫甙、芥酸有降低趋势。硒锌配施,油菜含油量、蛋白质、硫甙无变化,芥酸明显下降。     

有机-无机复混肥对大豆产量和品质的影响

有机－无机复合混肥能够促进大豆的生长发育，提高大豆的产量和品质，试验结果表明：与常规施肥相比，大豆施用有机－无机复混肥25.0kg增长11．1％,粗蛋白质提高1．04％，而粗脂肪下降0．2％，因此，有机－无机复混肥对提高大豆产量和生产高蛋白大豆具有重要意义。