Tomato seedling development is improved by a substrate inoculated with a combination of rhizobacteria and fungi

Chile's seedling production industry has been growing for the last 10 years, and demand has actually reached 1250 million seedlings per year. This system has special relevance due to the high cost of seeds. In addition, there is an increasing demand for substituting synthetic agrochemicals. Therefore, the potential use of plant growth-promoting rhizobacteria (PGPR) in tomato production has been investigated. Before sowing, the micro-organisms provided by Biogram S.A. were inoculated into the substrate diluted in 250 mL/L unchlorinated water. The experiment was laid out in a ‘split-plot’ design with the two plant substrates as main plots and the inoculants as subplots, including six replicates per treatment. Tomato seedlings were grown using two different plant substrates: a mixture of 70% peat and 30% perlite by volume, and a substrate with 20% peat, 20% perlite and 60% compost by volume, both inoculated with Bacillus subtilis or Pseudomonas fluorescens or Bioroot®, which is a commercial product containing B. subtilis, P. fluorescens, Trichoderma harzianum, yeast, algae and Nocardia. For control, uninoculated tomato seedlings were grown on the respective plant substrates. Variance analysis did not identify significant interactions between substrate type (main plots) and inoculation treatment (subplots), P ≤ 0.05. There were significant differences between inoculants (P ≤ 0.05). Means were compared by using the Tukey's multiple range test. Tomato growth in terms of leaf area (cm²/plant) and shoot and root dry weight (g/10 plants) was improved for the seedlings grown on the substrate with 70% peat and 30% perlite, compared to the compost containing an alternative that is valid for both uninoculated perlite peat and all inoculated treatments where perlite peat was outstanding. Inoculation with Bioroot® improved the leaf area, shoot dry weight, root dry weight, radical contact area, volume of roots and root forks compared with the control without inoculation, when both plant substrates were analysed together. Thus, inoculation with Bioroot® can be recommended as an alternative to tomato seedling growers' dependence on synthetic agrochemicals.     

Earthworm-Processed Organic Wastes as Components Of Horticultural Potting Media for Growing Marigold and Vegetable Seedlings

We germinated and grew tomato, pepper, lettuce, and marigold seedlings in a standard commercial soilless plant growth medium (Metro-Mix 360), and in coir/perlite and peat/perlite-based container media substituted with 10% or 20%, by volume, of vermicompost derived from pig manure or food wastes. Half of the treatments were watered with liquid inorganic fertilizer while the other half received only water. Germination rates of tomato, pepper, lettuce, and marigold seeds in the coir/perlite mixture did not differ significantly from that in Metro-Mix 360. However, the germination rate of tomato, pepper and lettuce seedlings was very low in the peat/perlite mixture. Substituting some of the peat/perlite mixtures with equal amounts of vermicomposts, particularly pig manure vermicompost, enhanced germination rates greatly, making it comparable to that in the commercial medium (Metro-Mix 360). Pepper, lettuce, and marigold seedlings grown in Metro-Mix 360, which already contains a starter nutrient fertilizer in its formulation, had greater root and shoot dry weights than those grown in the control media (coir/perlite mix and peat/perlite mix). Substituting coir/perlite and peat/perlite mixtures with 10% or 20% of either vermicompost enhanced the growth of seedlings significantly, resulting in an overall plant growth as good as and sometimes better than that in Metro-Mix 360. When the plants were provided daily with a complete fertilizer solution, marigold seedlings in peat-based substrate with 20% pig waste vermicompost, and lettuce seedlings in both coir and peat-based substrates, mixed with 20% food wastes vermicompost, produced greater shoot dry weights than those grown in the commercial potting medium. The growth enhancements tended to be greater in peat/perlite-based mixes than in coir/perlite-based mixes, more so with the addition of pig manure vermicompost than with food waste vermicompost. Earthworm-processed pig manure and food wastes would be suitable materials for inclusion into the formulation of soilless potting media, since substitution of these media with relatively low concentrations of vermicomposts can promote plant growth.     

生物氢烷工程沼渣用于油菜及菠菜育苗的效果

为探究将生物氢烷工程沼渣应用于蔬菜育苗基质生产的可行性,以油菜品种"华绿四号"、菠菜品种"先锋菠菜"为材料,按不同体积比将生物氢烷工程沼渣与土壤或草炭、蛭石和珍珠岩三者混配作为育苗基质,通过穴盘育苗试验研究生物氢烷工程沼渣对基质理化性质和油菜、菠菜幼苗生长的影响。结果表明:添加生物氢烷工程沼渣可显著改善基质的容重、总孔隙度、有机质含量、pH值和电导率EC(electronical conductivity)值等理化性质;适宜配比的生物氢烷工程沼渣对幼苗生长发育有一定的促进作用,其中T6(生物氢烷工程沼渣20%、草炭30%、蛭石25%、珍珠岩25%)的基质配方较为适宜,T6中油菜出苗率显著高于CK3(草炭50%、蛭石25%、珍珠岩25%)(P0.05),提高了14.3%,菠菜出苗率提高了12.4%,幼苗的株高、茎粗、单株叶面积显著高于或接近CK3(P0.05),幼苗根冠比和壮苗指数与CK3无显著差异;添加生物氢烷工程沼渣可使幼苗地下部生物量显著升高(P0.05),促进根系生长,使幼苗地上部、地下部生物量分配更加均衡。因此,生物氢烷工程沼渣具有一定的肥效,可部分替代草炭用于叶菜育苗基质生产,但使用前可考虑进行好氧堆肥处理进一步腐熟或与氮肥配施以提高肥效。     

奶牛粪蚯蚓堆肥的基质配方及对草莓育苗的影响

将奶牛粪蚯蚓堆肥与泥炭、珍珠岩和蛭石按不同比例进行复配,然后进行草莓育苗生长试验,通过分析草莓生长情况,筛选出适合草莓育苗的最佳基质配方。结果表明,复配后育苗基质的理化性质优良,适合草莓生长。与常规基质相比,添加不同量蚯蚓堆肥的育苗基质均不同程度促进了草莓母株和一级子苗的生长(除蚯蚓堆肥完全替代泥炭处理外),随着蚯蚓堆肥比例的增加,草莓植株生长情况表现为先上升后下降的趋势。所有处理中,以蚯蚓堆肥占育苗基质物料总体积1/3的配比处理(替代50%的泥炭)的综合效果最好,较常规基质能显著提高草莓母株和一级子苗的品质,母株的株高、生物量、根系形态指标、相对叶绿素含量(SPAD值)和过氧化物酶活性,以及一级子苗功能叶的叶柄长、叶面积和SPAD值等,该配方可推荐用于架式草莓工厂化育苗生产。     

牛粪蚯蚓堆肥基质对草莓生长的影响

将奶牛粪蚯蚓堆肥与泥炭、珍珠岩和蛭石按不同体积比例复配成3种草莓生长基质,体积比分别为0∶4∶1∶1(基质a),2∶2∶1∶1(基质b),4∶0∶1∶1(基质c),通过分析草莓的生长情况、果实产量和品质,筛选出适合草莓生长的最佳基质配比。结果表明,复配后生长基质的理化性质优良,适合草莓生长。3种基质中,以基质b效果最佳,综合来看,基质b栽培的草莓果实可溶性糖、糖酸比、可溶性固形物、抗坏血酸、可溶性蛋白和花青素含量均不同程度高于其他两种基质。此外,与基质a和基质c相比,基质b的草莓果实收获期提前了5~15 d。该配方可推荐用于架式草莓工厂化栽培生产。     

日光温室栽培基质有效导热系数预测模型

栽培基质为固流两相组成的多组分材料,其导热系数是日光温室热环境营造过程中重要的热参数之一,在温室地面热量的传输中起着重要的作用。为了预测日光温室生产中栽培基质的有效导热系数,以珍珠岩、蛭石、炉渣、河沙、椰糠、泥炭及腐熟牛粪与花生壳8种常用单一基质为研究对象,首先利用干燥与饱和状态下基质有效导热系数的测试结果,通过复合材料有效特性混合模型的反向计算,确定了8种单一基质的固相导热系数,得到珍珠岩、蛭石、炉渣、河沙、椰糠、泥炭及腐熟牛粪与花生壳的固相导热系数分别为0.058、0.139、0.252、0.817、0.148、0.518、0.262及0.066 W/(m·K);其次,利用复配基质有效导热系数的实测结果,通过复合材料有效特性混合模型的正向与反向计算,明确了组成固相的各组分呈并联关系排列,并确定了复配基质中固相导热系数与基质各组分体积比例的关联;进一步将复配基质在不同饱和度下的有效导热系数实测值与基于6种复合材料导热系数模型理论计算值进行比较。结果表明：并联模型适用于复配基质有效导热系数的理论计算,构建了日光温室栽培基质有效导热系数的预测模型。采用实际生产中常用的4种育苗和栽培基质在不同饱和度下的有效导热系数对所建模型进行检验,模型预测值和实测值的平均相对偏差范围为0.42%～1.76%。基于并联模型构建的有效导热系数预测模型能够较为准确的计算日光温室栽培基质在不同饱和度下的有效导热系数。     

Usage of Herbal (Thyme and Chicory) Waste as an Organic Substrate in Cucumber Production

This experiment was conducted in a greenhouse to study the effect of herbal waste substrate as local substrate in cucumber (Cucumis sativus cv. Zomorod) production. Treatments included thyme: perlite (T50:PR50); thyme: perlite (T25:PR75); thyme, perlite: peat moss (T25:PR25:P50); chicory: perlite (C50:PR50); chicory: perlite (C25:PR75); chicory: perlite: peat moss (C25:PR25:P50), and perlite (100) as control. The experiment was conducted based on a completely randomized design with 5 replications. The results showed that fruit number and fruit weight were more (about 54% and 65%, respectively) in C25:PR25:P50 treatment than that in the control. Also, the highest leaves number, shoot length, shoot fresh and dry weights, and root fresh and dry weights were observed in this treatment (C25:PR25:P50). The highest K, Ca, Mg, Mn, and Fe contents were obtained in C50:PR50 treatment. Zn and Cu significantly increased in C25:PR25:P50 treatment. In general, substrate containing chicory was more effective than substrate containing thyme. As comparison among all the substrates, substrate containing chicory, C25:PR25:P50 had a significant effect on growth and yield, and C50:PR50 was more effective than the other substrate on nutrient element concentrations.     

Effects of Different Substrate Ratios on the Growth and Physiology of Sequoia sempervirens Container Seedlings

Abstract

Container technology can effectively control soil environment and nutrient status to obtain the optimal plant growth condition. Peat, green waste compost (GWC), soil and perlite were used as substrate materials to study the effects of different substrate ratios on growth and physiology of 1.5-year-old Sequoia sempervirens container seedlings. The optimal substrate ratio of S. sempervirens container seedlings was obtained by L₉ (3⁴) orthogonal design and was finally evaluated by principal component analysis. The volume ratio of peat: GWC: soil: perlite of 4: 1.5: 1: 2 was the best substrate ratio for S. sempervirens across all parameters, whose porosity, bulk density (BD) and gas-water ratio (GWR) were within the ideal ranges. The concentrations of total nitrogen (TN) of 1.40% and total phosphorus (TP) of 0.13% were the highest among the nine different substrates. The total potassium (TK) and electrical conductivity (EC) were 0.13% and 0.70?ms cm^?1, respectively. In addition, the plant height and ground diameter growing in the substrate were increased by 28% and 39% compared to their respective initial values. The content of peat and GCW had significant effects on growth (p?<?0.01). The GWR in T2 (peat: GWC: soil: perlite = 6: 1: 0.5: 2) and T6 (peat: GWC: soil: perlite = 4: 0.5: 0.5: 1) are not suitable for S. sempervirens container seedlings. The PCA ranking of the 9 groups of substrates is: T8?>?T1?>?T4?>?T3?>?T2?>?T5?>?T7?>?T9?>?T6. The combination of peat, GWC, soil and perlite in an appropriate ratio could provide a good environment for S. sempervirens container seedlings.     

Municipal Solid Waste (MSW) Compost as a Tomato Transplant Medium

For 3 years, different types of growing media were evaluated in nursery-produced tomatoes (Lycopersicum esculentum Mill. cv “Atletico”). Five mixtures of substrates were used: old peat (65%) + white peat (30%) + perlite (5%), old peat (65%) + MSW compost (30%) + perlite (5%), MSW compost (65%) + white peat (30%) + perlite (5%), MSW compost (95%) + perlite (5%) and MSW compost (50%) + cocofiber (50%). Various seedling indices were measured in order to assess the quality of the nursery-produced plant. The quality of the MSW compost used (pH, salinity, organic matter) bore a strong influence on results. Electrical conductivity (EC) values of the MSW compost of over 9 dSm^?1 produced poorer quality tomato seedlings in the mixture of substrates with peat. The use of MSW compost as the only substrate and the mixture of MSW compost with cocofiber had a lower growth index and poorer performance than the standard peat mixture. However, growth and development of the tomato seedlings in the mixture: old peat (65%) + MSW compost (30%) + perlite (5%) were similar to that obtained with the standard mixture: old peat (65%) + white peat (30%) + perlite (5%).     

草炭与珍珠岩对土壤种子库种子萌发特征的影响

[目的]探究基质添加对土壤种子库种子萌发特征的影响,为今后土壤种子库应用于植被恢复工程提供有价值的参考。[方法]借鉴日本植被恢复的先进经验,采用温室萌发法探究有机基质(草炭)、无机基质(珍珠岩)及混合基质(草炭与珍珠岩)添加对土壤种子库种子萌发特征的影响。[结果]草炭与珍珠岩混合基质对土壤种子库密度、物种多样性的促进作用更为明显,当混合基质与表土配比为20%和30%时,Shannon-Wiener多样性指数和种子库密度分别达到最高值;种子库萌发曲线中,混合基质组的萌发效果明显高于空白组和其他组;种子库密度与土壤因子的多元回归分析中,C,N,P,K元素均对种子库密度影响显著,进一步通过CCA排序法,分析发现大部分植物均对土壤含水率和C,N,P,K等元素有一定程度上的要求。[结论]向表土中添加混合基质作为一种人工措施,能有效地促进种子库密度和物种多样性,可为植被恢复工程提供具有实用价值的参考。     

Determination of total phosphorus in soil using simple Kjeldahl digestion

Abstract

Following observation of severe chlorosis and dieback of meri‐stem tissue in asparagus seedlings started in the greenhouse in a soilless media, a study was conducted to determine if the growth patterns were associated with one or more of the media components. Asparagus seedling growth using several potting media was compared. Treatments included single component media, washed sand, perlite, peat, Plainfield loamy sand [a local soil (PLS)], plus 1: 1 mixtures of peat/perlite, washed sand/peat, PLS/perlite, washed sand/peat, and PLS/peat. Abnormal growth patterns were observed in several of the media. Chlorosis was associated with high pH which occurred in perlite, washed sand, and their combinations. Chlorotic plants were characterized by low root and fern dry weights and low fern to root ratios. Meristem dieback occurred in several media treatments and did not appear to be pH related. Plants exhibiting dieback had fern to root ratios approaching 1 if they were not also affected by chlorosis. Nutrient availability was suspected to be a cause but this hypothesis was not substantiated by data collected in this experiment. Asparagus growth in a mixture of Plainfield loamy sand and peat was the highest and was similar to that of field grown seedlings.     

Effect of Substrate Reutilization on Yield and Properties of Melon and Tomato Crops

Certain ecologically-friendly substrates have recently been shown to be perfectly viable alternatives to other more traditional ones such as rockwool, perlite, or some hydroponic systems. However, in order to be competitive for vegetable production in the Mediterranean region, substrates must be used for at least one year. The present study assessed random samples of two commercial substrates, almond shell and compost from greenhouse vegetable residue. The substrates were evaluated as growing media for long-term soilless production. Three experiments were conducted to evaluate the effects of reusing these substrates, comparing them with rockwool in terms of yield and fruit quality characteristics of melon and tomato. The physical, physico-chemical, and chemical properties studied differed significantly on reutilizing these materials. However, these differences did not prove to be limiting factors when fertigation parameters applied were adjusted according to substrate properties. The results suggest that compost and commercial almond shells seem to be acceptable growing media after at least 265 and 530 days of reutilization, respectively.     

生物质炭醋糟复配物代替草炭对辣椒幼苗生长的影响

生物质炭的农业利用日益受到关注。针对草炭资源日益耗竭的问题,以药渣炭、木屑炭和猪粪炭为试验对象,配比一定量的醋糟,分析了不同配比生物质炭复合基质对辣椒幼苗生长的影响,探讨了生物质炭复合基质代替草炭基质的可能性。试验结果表明:生物质炭在与醋糟按4∶2、3∶3、2∶4等不同配比混合后,基质的pH大多数在6.0~7.5,基质的通气孔隙有所提高。综合整个幼苗生育期,含20%生物质炭的各复合基质处理的辣椒幼苗株高、茎粗、叶面积、地上部生物量均显著优于对照草炭基质;含20%、40%药渣炭的基质处理的幼苗根表面积、根体积表现较好,在前期与草炭基质无显著差异,后期显著高于草炭基质。药渣炭和木屑炭与醋糟混配基质的壮苗指数优于草炭处理,其中B1A2(药渣炭∶醋糟∶蛭石∶珍珠岩=4∶2∶3∶1)、B1A4(药渣炭∶醋糟∶蛭石∶珍珠岩=2∶4∶3∶1)、B2A4(木屑炭∶醋糟∶蛭石∶珍珠岩=2∶4∶3∶1)处理的壮苗指数均显著高于其他处理。综合评价各生长指标,B1A2和B1A4处理基质的表现最好,可代替草炭基质在辣椒育苗上应用。     

Growth of Hedera helix L. Container Plants in Compost Substrates Made with Miscanthus ogiformis Honda Straw and Various N-Sources

Ammonium sulfate or urea were added as N-source to shredded straw of Miscanthus ogiformis ‘Giganteus’ and water was included as control. The combined materials were composted for seven months, and the resulting composts were tested as growth substrates for nursery container plants and compared with fertilized and unfertilized peat substrates. The pH was below recommended level for the compost substrate made with ammonium sulfate and for the unfertilized peat substrate throughout the experiment. Electrical conductivity and concentrations of most nutrients were low and decreased throughout the experiment for all growth substrates. Shrinking of the growth substrates after 4, 12 or 17 months was larger for compost substrates than for peat substrates. Bulk density increased in compost substrates and decreased in peat substrates, while the total loss of C was greater in compost substrates than in peat. Water retention was lower and air volume greater for compost substrate made with ammonium sulfate than for fertilized peat. Algae and mosses did not occur on Miscanthus compost growth substrates in contrast to peat substrates. The shoot length and dry matter of Hedera helix, produced after four and 12 months of growth, and five months following cut back, showed that plants can grow well in compost substrates made of Miscanthus straw and ammonium sulfate or urea. However, the compost substrates could not fully substitute for fertilized or unfertilized peat substrate with respect to dry matter production.     

Hydrochars from Biosolids and Urban Wastes as Substitute Materials for Peat

Peat is the most widely used substrate component and extensively used in greenhouse cultivation, landfill cover soils, urban parks and gardens, urban agriculture or green roofs, due to its excellent combination of physicochemical properties. The production of hydrochar by hydrothermal carbonization (a process at lower temperatures than pyrolysis and using wet conditions) could industrially reproduce the initial conditions of biomass humification and lead to materials with similar properties to those of peat. The objective of this work was to compare peat (PT, Control), a hydrochar prepared from biosolids (HSL), a hydrochar prepared from the organic fraction of urban wastes (HUW) and two mixtures (PT + HSL and PT + HUW) at a 50% volume rate for their potential use as substrates with multiple applications. Ryegrass was established at a rate of 40 g seeds cm⁻² in the potting mixtures. Hydrophysical and biochemical properties (microbial biomass and the enzymes dehydrogenase, β‐glucosidase and phosphomonoesterase) were analyzed for PT, HSL, HUV and their combination (PT + HSL and PT + HUW). Treatments with biosolids hydrochar increased ryegrass production by 184% (HSL) and by 216% (PT + HSL) dry weight compared to the control (peat). Biochemical properties depended strongly on hydrochar type, while the hydrophysical properties of the hydrochars were similar to those of peat. Overall, our results found hydrochar–peat mixtures (PT + HSL and PT + HUW) to be suitable for the preparation of growing media. Copyright © 2017 John Wiley & Sons, Ltd.     

椰糠复合基质对番茄穴盘幼苗生长效应的综合评价

为缓解草炭基质的使用压力及椰子果实外壳被焚烧丢弃造成的资源浪费和环境污染等问题。本试验以毛粉‘812’为试验材料,研究不同复合基质对番茄幼苗生长、叶片生理活性及光合特性的影响,通过对不同复合基质育苗效果的综合评价筛选出最佳的复合基质配方。结果表明:T9复合基质配方〔V（椰糠）∶V（蛭石）∶V（珍珠岩）=3∶2.5∶2.5〕的通气孔隙度、气水比、pH、叶绿素相对含量、可溶性糖含量、叶绿素总含量、气孔导度（Gs）、蒸腾速率（Tr）、根系活力、G值及壮苗指数相对较高,分别为10.46%、0.19、7.59、46.59、0.154 mg g?1、1.356 mg g?1、0.18 mol m?2 s?1、9.59 mmol m?2 s?1、11.44 μg（g h）?1、18.67 mg d?1、0.37。利用主成分分析将番茄幼苗的各项指标进行综合评价,结果显示:不同复合基质配方的综合排名由高到低为T9〔V（椰糠）∶V（蛭石）∶V（珍珠岩）= 3∶2.5∶2.5〕 > T8〔V（椰糠）∶V（蛭石）∶V（珍珠岩）= 4∶3∶1〕 > T6〔V（椰糠）∶V（蛭石）∶V（珍珠岩）= 5∶2∶1〕 > T5〔V（椰糠）∶V（蛭石）∶V（珍珠岩）= 5∶1∶2〕 > T7〔V（椰糠）∶V（蛭石）∶V（珍珠岩）= 4∶1∶3〕 > T1〔V（草炭）∶V（椰糠）∶V（蛭石）∶V（珍珠岩）= 3∶1∶2∶2〕 > T4〔V（椰糠）∶V（蛭石）∶V（珍珠岩）= 4∶2∶2〕 > T2〔V（草炭）∶V（椰糠）∶V（蛭石）∶V（珍珠岩）= 2∶2∶2∶2〕 > T3〔V（草炭）∶V（椰糠）∶V（蛭石）∶V（珍珠岩）= 1∶3∶2∶2〕 > CK〔V（草炭）∶V（蛭石）∶V（珍珠岩）= 4∶2∶2〕。由此可见,T9复合基质配方〔V（椰糠）∶V（蛭石）∶V（珍珠岩）= 3∶2.5∶2.5〕可作为番茄适宜的穴盘育苗基质配方。     

EVALUATION OF ORGANIC SOLID WASTES COMPOSTS AS PEAT SUBSTITUTES FOR SEEDLING PRODUCTION

This research work was performed to investigate the possibility of using composted herb residues (C1), co-composted sewage sludge with sawdust (C2), co-composted pig manure with sawdust (C3), and co-composted pig manure with spent mushroom (C4) in the production of horticultural seedlings to replace part of peat in the growing media. The proportions of each compost in the mixtures elaborated with peat were 50%, 75%, and 100% (v/v), respectively. The substrate of 100% commercial peat was used as the control. First, some physical, physical-chemical, and chemical properties of these substrates were determined. Second, four kinds of plants tomato, cucumber, bermudagrass, and impatiens were used to evaluate the possibility of different composts to replace part of peat. The seed germination rate, fresh weight and nutrient concentrations of seedling were then measured. We found that the physical, physical-chemical and chemical properties of these substrates were statistically influenced by the type and the proportion of compost in the substrates. The substrates elaborated with C1 and C2 showed adequate physical and chemical properties for their use as substrate in horticultural seedlings production. The highest germination of cucumber, tomato, bermudagrass and impatiens all occurred at C1 based substrate. Seedling grown in the C1 and C2 based substrate reached better growth and nutrition than peat. Our results suggested that the C1 and C2 were good alternative to peat-based substrate for seedling production, especially at the rate of 75% and 100% of C1 and 50% of C2, which have shown beneficial effects on the seedling production of cucumber, tomato, bermudagrass and impatiens compared to the control. However, C3 and C4 were not always adequately used in substituting expensive peat.     

Evaluation of Composted Green Waste In Ornamental Container-Grown Plants: Effects on Growth and Plant Water Relations

Ornamental nurseries extensively utilize peat in commercial soilless potting media, but its use as an organic amendment with a superior water holding capacity is challenged by economic and environmental pressures so potential alternatives to peat need to be investigated. In our experiment, commercially available peat-based soilless mixes were amended with increasing composted green waste (CGW) percentages. Results on Photinia X fraseri and Viburnum tinus suggest that CGW could partially substitute peat in containerized nursery production, with a different effectiveness related to species behavior. Viburnum seemed to be less affected by CGW addition (only CGW-based media, T₁₀₀, showed a significant difference compared to peat-based media, used as control), which on the contrary hardly affected Photinia growth in terms of biomass production and quality. On the other hand, a higher CGW content (75% or 100%) also improved plant susceptibility to water shortage. Concluding, peat-based media partially amended with CGW may have positive agronomic and economic consequences for commercial ornamental nursery production.     

Alternatives to peat as a carrier for rhizobia inoculants: Solid and liquid formulations

Many of the microbial inoculants all over the world are based on solid peat formulations. This has been mostly true for well developed legume inoculants based on selected rhizobial strains, due to peat bacterial protection properties. Six carriers (bagasse, cork compost, attapulgite, sepiolite, perlite and amorphous silica) were evaluated as alternatives to peat. Compost from the cork industry and perlite were superior to peat in maintaining survival of different rhizospheric bacteria. Other tested materials were discarded as potential carriers for soybean rhizobia. Also, different liquid culture media have been assayed employing mannitol or glycerol as C sources. Some media maintained more than 10⁹ cfu ml^?1 of Sinorhizobium (Ensifer) fredii SMH12 or Bradyrhizobium japonicum USDA110 after 3 months of storage. Rhizobial survival on pre-inoculated seeds with both solid and liquid formulations previously cured for 15 days led to a higher bacterial numbers in comparison with recently made inoculants. An additional curing time of solid inoculants up to 120 days had a beneficial effect on rhizobial survival on seeds. The performance of different formulations of two highly effective soybean rhizobia strains was assayed under field conditions. Soybean inoculated with cork compost, perlite and liquid formulations produced seed yields that were not significantly different to those produced by peat-based inoculants.     

酒糟等农业废弃物的堆肥化及水稻育秧基质研发

本试验旨在以农业有机废弃物酒糟为主要原料,制成高效水稻育秧基质。首先,以酒糟配合小麦秸秆、菇渣进行发酵腐熟试验,得到腐熟基质原料。然后,以蛭石、珍珠岩为辅料制成不同配比的基质进行水稻育秧试验,筛选高效水稻育秧基质。结果表明,通过堆肥发酵得到的腐熟堆肥,可作为水稻育秧基质的原料,以(酒糟+秸秆)堆肥60%+蛭石30%+珍珠岩10%(T6)处理的综合效果最好,其在水稻幼苗的株高,全氮、磷、钾含量,根系活力等方面显著优于市售商品基质(T8)处理,分别比T8处理增加13.94%、12.68%、24.62%、5.77%、15.78%,是较理想的水稻育秧基质。