平菇栽培料中添加胡萝卜樱试验

以生产上常用配方为对照,在平菇栽培料中添加2％～6％的胡萝卜樱,以菌丝长速、子实体产量等为指标进行对比,研究平菇生产中胡萝卜樱的最佳添加比例.结果表明:在平菇生产中,可以添加2％～6％胡萝卜樱,其中添加4％效果最好,生产上应重点推广使用;处理2(胡萝卜樱添加量2％)、处理4(胡萝卜樱添加量6％)和处理1 (CK)差异不显著;处理3(胡萝卜樱添加量4％),菌丝长速指标显著高于处理1 (CK).     

云南省部分地区食用菌重金属含量的分析及评价

对云南文山和保山市售13种鲜食用茵样品中的铅、镉、砷、汞、铜的含量进行了检测,并结合国家卫生质量标准(GB 7096-2003)及《绿色食品-食用菌》NY/T 749-2003,对被测食用菌中的重金属含量进行安全评价.结果表明:产自文山和昆明的被检食用茵样品中As、Cd、Pd的含量严重超出国家卫生限量标准,产自保山的食用菌重金属Cd含量严重超标,As、Pd在部分样品中也超标.该研究对云南省食用菌生产市场安全性质量控制提出了警示.     

菌糠栽培对温室番茄生长发育和干物质积累的影响

为摸清菌糠在无土栽培中的应用效果,以菌糠、炉渣、河沙不同配比的栽培基质进行日光温室越冬茬番茄“印第安”的种植试验,研究栽培基质对番茄植株性状和干物质积累量的影响.结果表明:在营养生长期番茄的株高平均日增长1.0 cm以上,定植后90 d株高均达100 cm左右,茎粗达1.0 cm左右,株幅达50 cm以上,果穗达4穗,定植后140 d测得植株总鲜重都在200 g左右,干重30～40 g之间,干鲜比16.21％～17.86％,根冠比10.14％～12.93％,各生长发育性状处理间差异不大.说明以菌糠为主的3个不同配比栽培基质,均能满足番茄植株的正常生长和发育.     

喷施蔗糖基聚合物对平菇产量和品质的影响

试验在平菇子实体生长期间采用不同浓度的蔗糖基聚合物进行喷施处理,研究其对平菇产量和品质影响。结果表明,在试验浓度范围内,蔗糖基聚合物对平菇具有显著的增产增效作用。尤以浓度为2%的处理效果最好,鲜菇可增产23.8%,生物效率提高17.8%;子实体营养成分多糖、蛋白质和维生素C含量也分别提高32.1%、31.3%和3.1%;此外一些对人体重要矿物元素（Ca、Mg、Fe、Mn、Zn、Cu）的含量也均有明显提高。     

Urea hydrolysis in wetland soil amended with Sesbania aculeata green manure and rice straw

Summary The effect of incorporating sesbania and rice straw and of period of decomposition on urea hydrolysis was studied in a wetland soil under laboratory conditions. Urea hydrolysis proceeded more rapidly in the crop residue-amended soil than in the control soil, and increased with increases in the rate of addition of crop residues and with longer periods of decomposition. Irrespective of amendment treatment, urea hydrolysis followed first-order reaction kinetics, and rate constants in the unamended soil ranged from 0.021 to 0.024 h^-1 after urea application of 200 g N g^-1 soil. In the amended soil, hydrolysis rates ranged from 0.033 to 0.149 h^-1 with sesbania and 0.071 and 0.250 h^-1 with rice straw, depending on the length of decomposition period.     

不同秸秆还田方式对红壤性质及花生生长的影响

通过田间小区试验研究化肥配合不同秸秆还田方式对红壤养分、生物学特性和作物生长的影响。结果表明,与其他(NPK、NPKD1、NPKD2)处理相比,氮磷钾化肥配合秸秆直接还田(NPKJG)处理土壤碱解氮降低了7.88%~31.37%,速效磷降低了7.72%~23.81%。各处理土壤脲酶活性在花生的生长期间先降低后升高,而转化酶活性先升高后降低(除NPK处理的转化酶活性持续降低外)。氮磷钾化肥配合Fe SO4促腐秸秆堆肥还田处理(NPKD2)提高了土壤脲酶活性26.14%,而配合碱渣促腐秸秆堆肥处理(NPKD1)提高了土壤转化酶活性66.13%。氮磷钾化肥配合Fe SO4促腐秸秆堆肥处理土壤微生物生物量碳含量较高,且提高了花生各农艺性状指标和产量。     

补充灌溉、氮素营养与秸秆覆盖对冬小麦生长及产量的影响研究

大田试验研究补充灌水、施N肥与秸秆覆盖对冬小麦根系和地上部生长、产量及其构成因子的影响结果表明 ,施N肥对冬小麦生长发育和产量的效应最明显 ,单独覆盖秸秆或补充灌水基本无效甚至出现副作用。施用N肥和秸秆覆盖可促进冬小麦根系发育和地上部生物量累积。肥料供应充足时覆盖秸秆对冬小麦根系的作用与水分状况有关 ,土壤水分胁迫下秸秆覆盖效果不明显 ,此时施用N肥甚至出现一定负效应。水分充足与否 ,施N肥和秸秆覆盖均对冬小麦产量的形成有一定协同效应 ,补充灌溉与施用N肥和秸秆覆盖配合处理小麦产量最高。     

Effect of straw,cellulose and lignin on the turnover and availability of labelled ammonium nitrate

Summary An experiment was carried out to investigate how straw, cellulose and lignin affect the turnover and availability of inorganic labelled N in soil. The experiment comprised an incubation period in which the soil was incubated with ¹⁵NH₄ ¹⁵NO₃ and organic materials followed by drying and by cropping the soil with Lolium perenne. The incubation period lasted 148 days during which soil samples were taken 36 and 148 days after the beginning of incubation. Addition of organic materials to the soil promoted the incorporation of inorganic N into organic matter and decreased apparent N denitrification losses during the first period of incubation (0–36 days after beginning of incubation). In this respect straw and cellulose were more effective than lignin. The organic materials also promoted the fixation of NH₄ ⁺ by clay minerals. In all treatments highest fixation of labelled NH₄ ⁺ by clay minerals was found at the end of the incubation period. During the cropping period high apparent denitrification losses were observed particularly in the straw and cellulose treatment. Hence the recovery of labelled N by Lolium was particularly low in these treatments while in the control treatment the ¹⁵N recovery was about twice as high.     

Evidence that straw does not increase the mobilization of N from decomposing salal (Gaultheria shallon Pursh.) leaf litter

We tested whether straw could induce higher N release from decomposing salal leaf litter, which ostensibly interferes with mineralization of N. We mixed forest floor material from two forest types with ¹⁵N-enriched salal leaf litter, and incubated the mixtures 3 years with and without straw amendments. The amounts of N, as well as the relative amounts of ¹⁵N, extracted in five fractions were, respectively, 29-93 and 25-82% lower in straw-amended forest floor. Results suggest that straw diverted microbial decomposition activity away from the more recalcitrant litter fractions. Previous reports of higher mineral-N availability in straw-amended forest floors are best explained by a fertilizer effect of straw as opposed to a ‘priming effect’.     

Carbon cycling in rice field ecosystems in the context of input, decomposition and translocation of organic materials and the fates of their end products (CO2 and CH4)

Rice fields are intensively managed, unique agroecosystems, where soil flooding is general performance for rice cultivation. Flooding the field results in reductive soil conditions, under which decomposition of organic materials proceeds during the period of rice cultivation. A large variety of organic materials are incorporated into rice soils according to field management. In this review, the kind and abundance of organic materials entering carbon cycling in the rice field ecosystem are evaluated first. Then, decomposition of plant residues and soil organic matter in rice fields is reviewed quantitatively. Decomposition of plant residues is shown to be the active process in carbon cycling in rice fields. Rice releases photosynthates into the rhizosphere (rhizodeposition), and they follow a different avenue of decomposition in soil from that of plant residues. Incorporation of rhizodeposition into microbial biomass and soil organic matter during the period of rice cultivation, and their fates after harvesting are evaluated quantitatively from ¹³C pulse labeled experiments. Percolating water transports inorganic and organic carbon from the plow layer to the subsoil layer. The amounts of their transport and accumulation in the subsoil layer are evaluated in relation to the amounts of soil organic C in the plow layer. Not only CO₂ but also CH₄ are produced in the decomposition process of organic materials in flooded rice fields. CH₄ evolution from rice fields is of global concern from the viewpoint of global warming. Origins of CH₄ evolved from rice fields are estimated first, followed by the fates of CH₄ in rice field ecosystems. Rhizodeposition is shown to be the main origin of CH₄ evolved from rice fields. Evolution to the atmosphere is not the sole pathway of CH₄ produced in rice fields. The amounts of CH₄ retained in soil, percolated to the subsoil layer and decomposed in soil are evaluated in the context of the amounts of CH₄ efflux. Thus, this review focuses on carbon cycling in the rice field ecosystem from the viewpoints of input, decomposition, and translocation of organic materials and the fates of their end products (CO₂ and CH₄).