{"id":625,"date":"2026-05-26T01:29:44","date_gmt":"2026-05-26T01:29:44","guid":{"rendered":"https:\/\/rock-crusher-tractor.com\/?p=625"},"modified":"2026-05-26T01:29:44","modified_gmt":"2026-05-26T01:29:44","slug":"certified-seed-potato-production-korea-stone-clearance","status":"publish","type":"post","link":"https:\/\/rock-crusher-tractor.com\/hi\/certified-seed-potato-production-korea-stone-clearance\/","title":{"rendered":"Certified Seed Potato Production \u2014 Stone Clearance and Land Management Standards"},"content":{"rendered":"
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Certified Seed Potato Production \u2014 Why the Strictest Stone Clearance Standard Also Pays the Highest Price<\/h1>\n

Korean certified seed potato (\uc528\uac10\uc790) production commands a 30\u201350% premium over table potato at the same yield. The trade-off is the strictest land preparation and stone clearance standard in Korean potato production \u2014 zero defect tolerance, NAAS field inspection, and certified lot traceability from planting to supply.<\/p>\n

\uc528\uac10\uc790 \uc0dd\uc0b0 \uc7a5\ube44 \ubb38\uc758<\/a><\/p>\n<\/div>\n<\/div>\n

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Korean certified seed potato (\uc528\uac10\uc790, \u7a2e\u85af) is produced under the oversight of the National Institute of Agricultural Sciences (NAAS, \uad6d\ub9bd\ub18d\uc5c5\uacfc\ud559\uc6d0) and distributed through the provincial agricultural technology center (\ub18d\uc5c5\uae30\uc220\uc6d0) network for replanting by commercial highland potato producers. Certified seed potato must be: free from specified diseases and pests; of verified variety purity; within defined size grade; produced on approved land; and inspected at multiple growth stages by NAAS field inspectors.<\/p>\n

The land preparation standard for certified seed potato production is the strictest in Korean potato agronomy \u2014 stricter than processing potato (Atlantic) production and stricter than fresh market table potato. This is because certified seed potato is the upstream input that determines the quality of the entire downstream commercial potato production system. Disease carried in certified seed infects the buyer’s field for the full production season; physical damage from stone contact produces seed pieces with irregular cut surfaces that are entry points for soil pathogens. Every stone management standard in certified seed production is therefore set to protect the integrity of the supply chain, not just the individual grower’s yield.<\/p>\n

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Why Certified Seed Potato Pays 30\u201350% Premium \u2014 and What That Requires<\/h2>\n

\"EP-PAI-2100<\/p>\n

The price premium for Korean certified seed potato versus commercial table potato reflects the value that commercial potato producers place on planting material with verified disease status and variety purity. A commercial highland potato farmer who purchases sub-standard seed \u2014 whether un-certified local stock or poorly managed certified stock \u2014 risks introducing late blight (\uac10\uc790\uc5ed\ubcd1), common scab (\ub354\ub385\uc774\ubcd1), or virus infection to their field at planting. The resulting disease pressure can reduce commercial yield by 20\u201340% in a bad infection year \u2014 a loss far exceeding the marginal cost difference between certified and un-certified seed.<\/p>\n

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The premium<\/p>\n

Korean certified seed potato prices run 30\u201350% above commercial table potato price at equivalent weight. For a 10 ha certified seed production operation at 30 t\/ha yield, the premium represents a significant margin improvement over commercial production \u2014 justifying the additional land preparation, inspection, and traceability overhead that certified production requires.<\/p>\n<\/div>\n

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The entry requirement<\/p>\n

Certified seed potato producer registration with NAAS requires: approved highland altitude (typically 400 m minimum for phytosanitary isolation), approved land inspection, clean field history (no potato in the same field for the previous 3 seasons), and compliance with NAAS production guidelines throughout the season including multiple inspector visits.<\/p>\n<\/div>\n

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The land standard<\/p>\n

NAAS field inspection for certified seed potato production includes assessment of field preparation quality \u2014 including stone clearance. Fields with visible stone contamination above threshold at the inspection date fail field approval and cannot be registered for the season’s certified seed allocation. Stone clearance to zero-tolerance standard is therefore both an agronomic requirement and an administrative prerequisite.<\/p>\n<\/div>\n<\/div>\n

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Why Certified Seed Potato Needs Stricter Stone Clearance Than Table Potato<\/h2>\n

\"PSW-3200<\/p>\n

Three specific mechanisms make certified seed potato more sensitive to residual stone than commercial potato production:<\/p>\n

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1<\/div>\n
Planting depth uniformity is more critical.<\/strong> Certified seed potato producers plant at tighter seed spacing (33\u201340 cm) and more uniform depth than commercial production \u2014 because size uniformity of the harvested seed tuber is what determines the tuber’s commercial value as planting material. Tubers that develop at variable depth (from planter deflection over stones) have variable size at harvest and fall outside the certified size specification (typically 28\u201355 g). Even 1\u20132 planting depth irregularities per 100 plants translate into measurable size non-uniformity at harvest in a crop where the harvested product is judged on dimensional specification.<\/div>\n<\/div>\n
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2<\/div>\n
Seed piece surface integrity is a disease vector.<\/strong> When certified seed tubers are cut for planting (large tubers are cut into two or more seed pieces), the cut surface must heal rapidly to resist soil pathogen entry. A tuber that is bruised or abraded by stone contact during mechanical harvest has damaged skin that provides less barrier to pathogen entry than an undamaged tuber. Certified seed producers who allow stone contact with harvested tubers risk introducing common scab and Rhizoctonia infection to the seed lot \u2014 contaminating the supply received by the buyer.<\/div>\n<\/div>\n
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3<\/div>\n
Lot traceability requires damage-free mechanical harvest.<\/strong> NAAS certified seed lot traceability requires that each harvested lot is tracked from field to storage to buyer. A mechanical harvest stoppage from stone damage to the EP-AWB-1600 share \u2014 mid-field \u2014 interrupts the lot continuity. Fields where stone-induced harvest interruptions force mixed-field collection into a single lot may fail the lot-separation requirements for certified seed registration. Certified seed producers have zero tolerance for harvest interruptions from stone damage precisely because the traceability record cannot accommodate the confusion that a mid-harvest equipment failure creates.<\/div>\n<\/div>\n<\/div>\n

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The Complete Stone Clearance and Land Preparation Sequence for Certified Seed Potato<\/h2>\n

\"THOR<\/p>\n

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Autumn (Year 0)<\/div>\n
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NAAS field inspection + soil sampling<\/p>\n

Submit field registration application to NAAS\/provincial technology center. Soil test for pH (target 5.5\u20136.5), P, K, organic matter. Begin 3-year crop history documentation.<\/p>\n<\/div>\n<\/div>\n

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Oct\u2013Nov (Year 0)<\/div>\n
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Autumn stone clearance \u2014 THOR 2.4 + CT-2100<\/p>\n

Completing stone clearance in autumn removes it from the compressed spring preparation window and allows NAAS pre-season inspection of a cleared field. All embedded stones above 5 cm removed. Autumn clearance is strongly preferred over spring clearance for certified seed fields.<\/p>\n<\/div>\n<\/div>\n

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Jan (Year 1)<\/div>\n
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Elite seed lot ordering \u2014 confirm variety with NAAS allocation<\/p>\n

Certified seed potato starter stock (\uc6d0\uc6d0\uc885 or \uc6d0\uc885) allocated by NAAS on a registered-producer basis. Order must be placed and confirmed well before the spring season as allocation is limited per producer registration.<\/p>\n<\/div>\n<\/div>\n

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Mar (Year 1)<\/div>\n
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Spring frost-heave check + EP-EW-4000 rake if needed<\/p>\n

After soil thaw \u2014 walk the autumn-cleared field and assess any frost-heave. For certified seed fields with autumn THOR clearance history, most spring frost-heave is within EP-EW-4000 rake capacity. THOR re-deployed only if significant frost-heave above 40 Kg is present.<\/p>\n<\/div>\n<\/div>\n

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Apr (Year 1)<\/div>\n
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\u092a\u0940\u090f\u0938\u0921\u092c\u094d\u0932\u094d\u092f\u0942-3200<\/a> rotavator at 1000 RPM \u2014 ultra-fine seedbed<\/p>\n

Certified seed potato requires finer seedbed fragmentation than commercial potato. Two PSW-3200 passes (first at 4 km\/h, second at 3 km\/h with 90\u00b0 cross-direction) produce the uniform 5\u201310 mm particle size that supports consistent planting depth and even emergence.<\/p>\n<\/div>\n<\/div>\n

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20 \u0905\u092a\u094d\u0930\u0948\u0932 \u2013 5 \u092e\u0908<\/div>\n
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\u092a\u094c\u0927\u0930\u094b\u092a\u0923 \u2014 \u0908\u092a\u0940-\u092a\u0940\u090f\u0906\u0908-2100<\/a> at certified spacing (33\u201340 cm)<\/p>\n

NAAS inspector visit before or at planting to confirm field preparation and seed lot identity. Seed lot ID documented at planting (field number, seed lot certificate number, planting date, row count).<\/p>\n<\/div>\n<\/div>\n

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\u0905\u0917\u0938\u094d\u0924-\u0938\u093f\u0924\u0902\u092c\u0930<\/div>\n
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Harvest \u2014 EP-AWB-1600, lot-by-lot traceability<\/p>\n

NAAS final field inspection before harvest. Harvest by field lot \u2014 each field section harvested separately, tagged with lot number, kept physically segregated in storage. Grading and size inspection post-harvest; certified weight and quantity documented for NAAS reporting.<\/p>\n<\/div>\n<\/div>\n<\/div>\n

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Altitude and Isolation \u2014 Why Highland Stone Land Is Preferred for Certified Seed<\/h2>\n

Korean certified seed potato production is concentrated in high-altitude highland zones for a specific phytosanitary reason: vector isolation. The primary virus diseases of Korean potato (PLRV, PVY, PVX) are transmitted by aphid vectors. Aphid populations are significantly lower at high altitude (600\u2013900 m) than in valley floor or lowland agricultural zones. Fields at high altitude are therefore inherently more isolated from aphid-vectored virus infection than lowland fields \u2014 making them suitable for certified seed production where virus-free status is the core quality requirement.<\/p>\n

This altitude requirement for certified seed production intersects directly with the stone problem that high-altitude Korean highland fields present. The same granite soils and severe frost-heave cycles that make highland land valuable for virus-isolated seed production also make it the most stone-challenged agricultural land in Korea. Certified seed potato producers are therefore simultaneously managing the most valuable potato product and the most demanding stone clearing requirement in Korean potato production.<\/p>\n

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The premium-to-clearance-cost calculation for certified seed<\/p>\n

At 10 ha certified seed production (30 t\/ha yield, 30\u201350% premium over table price): the additional revenue from the premium versus table potato production is substantial \u2014 easily 30\u201340\u00d7 the annual stone clearance operating cost for the same 10 ha. The stone clearance investment is therefore not a cost barrier to certified seed production \u2014 it is a small fraction of the premium income that the clearance investment enables. Certified seed producers who rationalise stone clearance cost savings as a margin improvement are actually trading a small operating cost saving for the risk of NAAS inspection failure, harvest equipment damage, or seed quality loss that cancels the entire premium income for the affected season.<\/p>\n<\/div>\n

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Stone Clearance Standard Comparison \u2014 Seed vs Processing vs Table Potato<\/h2>\n

\"CT-2100<\/p>\n

\n\n\n\n\n\n\n\n\n\n\n\n
\u0915\u093e\u0930\u0915<\/th>\n\uc528\uac10\uc790 Certified Seed<\/th>\nAtlantic Processing<\/th>\nFresh Market Table<\/th>\n<\/tr>\n<\/thead>\n
\u092a\u0924\u094d\u0925\u0930 \u0938\u0939\u093f\u0937\u094d\u0923\u0941\u0924\u093e<\/td>\nZero \u2014 NAAS inspected<\/td>\nZero (mech.)<\/td>\nZero (mech.)<\/td>\n<\/tr>\n
Clearance frequency<\/td>\nTHOR+CT-2100 every year (no exception)<\/td>\nTHOR+CT-2100 heavy years; rake light years<\/td>\nSame as processing<\/td>\n<\/tr>\n
Post-clearance inspection<\/td>\nNAAS field inspection required<\/td>\nOwn assessment<\/td>\nOwn assessment<\/td>\n<\/tr>\n
Seedbed standard<\/td>\nUltra-fine (2 rotavator passes)<\/td>\nFine (1 rotavator pass)<\/td>\nFine (1 rotavator pass)<\/td>\n<\/tr>\n
\u092c\u0940\u091c \u0930\u093f\u0915\u094d\u0924\u093f<\/td>\n33\u201340 cm (wider for size uniformity)<\/td>\n28\u201333 cm (dense for processing size)<\/td>\n25\u201330 \u0938\u0947\u092e\u0940<\/td>\n<\/tr>\n
Harvest traceability<\/td>\nMandatory lot separation by field<\/td>\nContract grade + weight only<\/td>\nMarket grade<\/td>\n<\/tr>\n
Price premium over table potato<\/td>\n30\u2013501\u091f\u0940\u092a\u09405\u091f\u0940<\/td>\n~10\u201315% (contract stability)<\/td>\nSpot market<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

In-Season Management \u2014 How Certified Seed Differs from Commercial Potato<\/h2>\n

Beyond land preparation and stone clearance, certified seed potato production requires stricter in-season management than commercial potato. Each of the following differs from standard commercial practice:<\/p>\n

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\u2460<\/span><\/p>\n

Disease roguing (\ubcd1\uc8fc \uc81c\uac70):<\/strong> NAAS protocols require certified seed producers to walk all fields regularly and remove (roguing) any plants showing symptoms of virus infection, late blight, or variety impurity \u2014 plants that do not conform to the expected variety phenotype. Rogued plants are removed from the field to prevent spread. Commercial potato producers do not typically rogue individual plants; certified seed producers must do so as a condition of certification.<\/p>\n<\/div>\n

2<\/span><\/p>\n

Aphid vector monitoring and control:<\/strong> Virus transmission by aphids is the primary quality risk in highland certified seed production. Certified seed producers maintain aphid monitoring traps in their fields throughout the growing season and implement aphicide applications at defined infestation thresholds \u2014 earlier and more systematically than commercial potato management requires. The highland altitude isolation advantage reduces but does not eliminate aphid pressure in all years.<\/p>\n<\/div>\n

\u2462<\/span><\/p>\n

Haulm destruction before harvest:<\/strong> Certified seed potato haulm (vine) is destroyed chemically or mechanically 2\u20133 weeks before harvest to allow tuber skin set before the EP-AWB-1600 lifter contacts the tubers. Skin set is more critical for certified seed than for commercial potato because (a) the seed tuber will be stored for several months and then cut before planting \u2014 damaged skin creates long-term storage rot entry points; and (b) certified seed is sold by weight, and damaged-skin tubers lose weight through dehydration faster than intact-skin tubers during storage.<\/p>\n<\/div>\n<\/div>\n

Post-Harvest Storage and Lot Management<\/h2>\n

Certified seed potato storage requirements are stricter than commercial table potato because seed tubers must remain physiologically viable for 8\u201312 months from autumn harvest to the following spring planting. Three storage conditions directly affect seed viability and lot integrity:<\/p>\n

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\ud83c\udf21<\/p>\n

\u092d\u0902\u0921\u093e\u0930\u0923 \u0924\u093e\u092a\u092e\u093e\u0928<\/p>\n

2\u20134\u00b0C for long-term dormancy maintenance. Below 2\u00b0C causes internal cell damage; above 6\u00b0C allows dormancy break and premature sprouting. NAAS certified seed storage facilities must have temperature-controlled cold storage.<\/p>\n<\/div>\n

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\ud83d\udca7<\/p>\n

\u0938\u093e\u092a\u0947\u0915\u094d\u0937\u093f\u0915 \u0906\u0930\u094d\u0926\u094d\u0930\u0924\u093e<\/p>\n

85\u201395% RH prevents dehydration shrinkage without promoting condensation that encourages Fusarium and bacterial soft rot. Seed tubers with damaged skin (from stone contact at harvest) dehydrate faster and rot more readily than undamaged tubers at the same storage conditions.<\/p>\n<\/div>\n

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\ud83d\udce6<\/p>\n

Lot segregation<\/p>\n

Each harvested lot (by field, by harvest date) must be physically segregated in storage \u2014 separate bins, bays, or rooms with lot identification labels. Mixed lots cannot be certified. NAAS inspectors verify lot segregation at storage inspection visits during the storage period.<\/p>\n<\/div>\n<\/div>\n

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Building a Certified Seed Potato Business \u2014 The Long-Term Perspective<\/h2>\n

Certified seed potato production in Korea is not a one-season decision \u2014 it is a multi-year infrastructure and management commitment. The NAAS registration process, the annual field inspection programme, the certified storage facility requirement, and the strict in-season management protocols all represent fixed infrastructure that has a meaningful cost in Year 1 but a much lower marginal cost in Year 2, 3, and beyond as the same certification infrastructure services the same registered fields.<\/p>\n

Korean highland farmers who have maintained certified seed potato production continuously for 5+ years consistently report that the premium income compounds annually without proportional increase in management cost \u2014 the stone clearance infrastructure is established, the NAAS registration is renewed rather than rebuilt, and the management experience from previous seasons reduces the per-season decision-making burden. The combination of altitude advantage (virus isolation), established stone clearance practice (zero-tolerance standard), and accumulated NAAS certification history makes a long-established Korean highland certified seed potato operation a durable production asset.<\/p>\n

Korea Watanabe’s machinery system \u2014 THOR 2.4, PSW-3200, EP-PAI-2100, EP-ERA cultivator, EP-AWB-1600 \u2014 provides the complete mechanised capability for certified seed potato production from stone clearance through harvest, with all machine configurations confirmed for Korean highland terrace conditions and NAAS field inspection requirements. Contact Korea Watanabe in January before your target production season to plan the complete system configuration for your specific field area and NAAS registration zone.<\/p>\n

\u0905\u0915\u094d\u0938\u0930 \u092a\u0942\u091b\u0947 \u091c\u093e\u0928\u0947 \u0935\u093e\u0932\u0947 \u092a\u094d\u0930\u0936\u094d\u0928\u094b\u0902<\/h2>\n
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\nDo I need a different THOR model for certified seed potato land versus standard commercial potato?<\/summary>\n

No \u2014 the same THOR 2.4 (180 HP, Kit Drawbar) used for commercial highland potato stone clearance is the correct machine for certified seed potato land preparation. The stone clearance operation itself does not change \u2014 the standard is the same zero-tolerance requirement. What changes is the frequency (THOR+CT-2100 every year for certified seed, versus every 2\u20133 years for established commercial fields) and the post-clearance inspection (NAAS field visit required for certified seed, self-assessed for commercial). The machine choice is the same; the management discipline is higher for certified seed.<\/p>\n<\/details>\n

\nHow do I register as a certified seed potato producer with NAAS?<\/summary>\n

Registration for certified seed potato production in Korea is administered through the National Institute of Agricultural Sciences (\uad6d\ub9bd\ub18d\uc5c5\uacfc\ud559\uc6d0) in coordination with your provincial agricultural technology center (\ub3c4 \ub18d\uc5c5\uae30\uc220\uc6d0). The registration process involves: field application with location, area, altitude, and crop history documentation; field inspection by NAAS or delegated inspector; confirmation of certified storage facilities; and agreement to comply with NAAS production protocols including multiple in-season inspector visits. Contact your provincial agricultural technology center for the current year’s application schedule and eligibility requirements \u2014 registration processes and deadlines are updated annually.<\/p>\n<\/details>\n

\nCan stone clearing machinery be included in certified seed potato production support programs?<\/summary>\n

Stone clearing machinery (THOR 2.4, CT-2100) used for certified seed potato land preparation qualifies under the standard \ub18d\uc9c0 \uc815\ube44 \uae30\uacc4\ub958 subsidy program, the same as for any highland agricultural use. In addition, certified seed potato producers may be eligible for enhanced production support through NAAS and MAFRA seed potato production programs, which sometimes include land improvement cost support as part of the certified production infrastructure. Confirm current enhanced support availability with your provincial agricultural technology center when registering as a certified seed producer. Korea Watanabe provides technical documentation for stone clearing machinery subsidy applications for certified seed potato operations.<\/p>\n<\/details>\n<\/div>\n

<\/p>\n

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\uc528\uac10\uc790 \uc0dd\uc0b0 \uc2dc\uc791? \ub3cc \uc81c\uac70 \uc7a5\ube44 + \uac10\uc790 7\ub2e8\uacc4 \uc2dc\uc2a4\ud15c\uc744 \ud568\uaed8 \uad6c\uc131\ud558\uc138\uc694.<\/p>\n

Field area + altitude + current tractor HP + NAAS registration status \u2192 THOR 2.4 + PSW-3200 + EP-PAI-2100 certified seed system configuration with row-spacing confirmation and NAAS documentation support. Korea Watanabe, Ansan-si, Gyeonggi-do.<\/p>\n

\u0939\u092e\u0938\u0947 \u0905\u092d\u0940 \u0938\u0902\u092a\u0930\u094d\u0915 \u0915\u0930\u0947\u0902<\/a><\/p>\n<\/div>\n

\u0938\u0902\u092a\u093e\u0926\u0915: \u0938\u0940\u090f\u0915\u094d\u0938\u090f\u092e<\/p>\n<\/div>","protected":false},"excerpt":{"rendered":"

Certified Seed Potato Production \u2014 Why the Strictest Stone Clearance Standard Also Pays the Highest Price Korean certified seed potato (\uc528\uac10\uc790) production commands a 30\u201350% premium over table potato at the same yield. The trade-off is the strictest land preparation and stone clearance standard in Korean potato production \u2014 zero defect tolerance, NAAS field inspection, […]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[31],"tags":[],"class_list":["post-625","post","type-post","status-publish","format-standard","hentry","category-application-and-technical-guid"],"_links":{"self":[{"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/posts\/625","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/comments?post=625"}],"version-history":[{"count":2,"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/posts\/625\/revisions"}],"predecessor-version":[{"id":627,"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/posts\/625\/revisions\/627"}],"wp:attachment":[{"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/media?parent=625"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/categories?post=625"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rock-crusher-tractor.com\/hi\/wp-json\/wp\/v2\/tags?post=625"}],"curies":[{"name":"\u0921\u092c\u094d\u0932\u094d\u092f\u0942\u092a\u0940","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}