Standard No.:	NY/T 2118-2012
English Name:	Plug seedling substrate of vegetables
Chinese Name:	蔬菜育苗基质
Professional Classification:	NY    Professional Standard - Agriculture
ICS Classification:	65.020.20 65.020.20    Plant growing 65.020.20
Source Content Issued by:	MOA
Issued on:	2012-2-21
Implemented on:	2012-5-1
Status:	valid
Target Language:	English
File Format:	PDF
Word Count:	6000 words
Translation Price(USD):	150.0
Delivery:	via email in 1 business day

1 Scope This standard specifies the quality requirements, test methods, inspection rules, packaging, marking, storage and transportation of plug seedling substrate of vegetables. This standard is applicable to the quality judgment of commercial plug seedling substrate of vegetables mainly composed of decomposed organic materials and natural minerals. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. GB/T 601 Chemical reagent - Preparations of standard volumetric solutions GB/T 1250 Rules for expression and judgment of limiting values GB/T 6679 General rules for sampling solid chemical products GB/T 6682 Water for analytical laboratory use - Specification and test methods GB 7859 Determination of PH value in forest soil GB 7865 Determination of exchangeable calcium and magnesium in forest soil GB 8172 Control standards for urban wastes for agricultural use LY/T 1229 Determination of hydrolyzable nitrogen in forest soil LY/T 1233 Determination of available phosphorus in forest soil LY/T 1236 Determination of available potassium in forest soil LY/T 1237 Determination of organic matter in forest soil and calculation carbon-nitrogen ratio LY/T 1243 Determination of cation exchange capacity in forest soil 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 substrate mixed lightweight material that can replace the soil, provide suitable nutrients and pH for crops cultivation, and have good water retention, fertilizer retention, ventilation performance and root fixation, including such constituents as turf, vermiculite, perlite, wood chips, crop straws, livestock excrement, barks and mushroom dregs 3.2 bulk density dry weight of substrate of unit volume, g/cm3 3.3 ventilatory porosity space occupied by air in substrate, which is expressed as the volume percentage (%) of the substrate 3.4 water retention porosity space occupied by moisture in substrate, which reflects the water retention capacity of the substrate to some extent, and is expressed as the volume percentage (%) of the substrate 3.5 general porosity sum of all pores (water retention pores and ventilatory pores) in substrate, which is expressed as the volume percentage (%) of the substrate 3.6 water air ratio ratio of ventilatory porosity to water retention porosity in substrate 3.7 cation exchange capacity adsorption capacity of cations in solution by a negatively charged substrate colloid by virtue of electrostatic attraction, which is expressed as the potential CEC (counted based on NH4+), cmol/kg 3.8 granule size diameter of substrate grains, mm 3.9 electric conductivity content of soluble salts in substrate, mS/cm 3.10 buffer capacity capability of substrate of mitigating the sharp changes in pH, which may maintain the relative stability of the substrate pH

Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Quality requirements 5 Test methods 6 Inspection rules 7 Packaging, marking, storage and transportation Annex A (Normative) Determination method for bulk density of substrate Annex B (Normative) Determination method for porosity of substrate Annex C (Normative) Determination method for relative moisture content of substrate Annex D (Normative) Determination method for electric conductivity of substrate Annex E (Normative) Operation specifications for emergence rate test