Seed Quality Assurance Malavika Dadlani Joint Director (Res) IARI, New Delhi Indian Seed Congress 2013
A Good Seed• Variety Performance• Seed quality are the two most important criteria on which rests the reputation of a seed company
Why Quality Seed• Seed is the basic input for higher productivity (15 - 20%)• Seed is the natural delivery system for enhancing productivity, profitability and resource use efficiency• Improves income, employment and livelihood
Seed Quality Genetic Purity Physical Purity Germination High seed vigour Good seed health -Dr. M.S. Swaminathan
Seed quality assurance“Seed quality assurance" implies that agencies charged with maintenance of seed quality cooperate with and support other areas of seed industry stakeholders to assure quality products to the end users. (M Larinde, FAO)
Rationale• Ensure that the best quality seeds are produced and sold to farmers• Prevent the spread of weed, pests and diseases• Meet consumer demands for specified qualities (and traits)• Cater to the needs of specialized farming, including mechanization• Provide basis for healthy competition among seed traders
Steps in QA• Pre-production Variety maintenance• Production of quality seed• Processing to obtain quality seed• Precision in post-production testing of seed quality• Seed quality enhancement• Packaging and storage to retain seed quality
Q2 Analyser http://www.astec-global.com/seed-analyserWorks on dry seeds and anon-destructive method. Butneeds to modify the designTo suit large no. of samlpes
Seed Germination & Seed Viability• TZ introduced by ISTA during 1960s• Though labour and time intensive for seed preparation & evaluation, still a valuable test for the industry As per ISTA, if 5 or > 5% seeds are FU, TZ test is a mustTZ test is simple and anyone can do it!
Genetic and Trait Purity• It is an important tool for variety maintenance as well as genetically pure commercial seed production,both in case of an OPV or hybrid variety.• Can be performed at different levels: based on field grow-out, lab tests, molecular tests etc.
Fingerprints and DNA fingerprintsFingerprints areunique to eachindividual DNA fingerprints are unique to each individual The probability of two unrelated individuals having identical DNA fingerprints is much lower than that of their fingerprints Sir Alec Jeffreys, Nature, 1984
DNA fingerprinting technology - Humans Vs Plant varieties Human Cultivars• One species, races??? • Multitude of species, subsp, races• Similarity in requirements • Diverse requirements• All out breeding • Veg. propagation to crossbred• One individual, one profile • Diverse genetic composition: purelines, inbreds, O/P, hybrids, composites, --- • Strong to weak substructure• Subtle substructure, varied • Common alleles across groups• Allelic specificity in races • Applications: identity, purity,• Applications: identity, relatedness, genetic makeup paternity • Techniques: SSR, SNP, AFLP….?• Techniques: SSR, SNP
Status of science VNTR-RFLP• Which technique to use!• Accessibility of technology RAPD• Applicability• Robustness• Repeatability• Ambiguities in profiles ISSR• Cost• Sample throughput Sequence/SNP• Automation ------ RAPD SSR VNTR
STMS markers for hybrid seed purity testing in cotton Rana et al…..
Cost considerations in purity testing• Present automated STMS profiling systems cost ~Rs. 40 /sample/marker• For 5000 plants – cost is Rs. 2.50 lakhs, but can be reduced by 1/10th with judicious bulking procedures.• Precision & sensitivity is high• Time scale: 900 plants, 6 days/5000 plants• No. of persons: 2
Seed Enhancement“Any post harvest treatment that improves germination / seedling emergence or facilitate the development of more number of normal, rapid, uniform and healthy seedlings in the field conditions.” McDonald (2000)
„Priming of an Idea-Invigoration of Seed‟Heydecker (1973)• Prof. Heydecker’s pioneering work on vegetable seed priming (at Nottingham University) paved the way for an array of technologies based on the basic principle of metabolic advancement of seeds for enhancing its performance on subsequent sowing, either immediately or after a period of storage, and under optimal or sub-optimal conditions of growing.
Magnetic seed treatmentGuoys balance Sample holderGauss meter + Pole piecescontroller MF probe Power pack Indigenously fabricated generator for seedtreatment (IARI, 2010)
Yield and growth attributes of maize seed exposed to electro-magnetic field Treatment Plant Days Cob Grain height to 50% weight yield Control (cm) silking (kg/plot) kg/plot Treated Control 155 48 8.7 6.3 Control 100 mT 166 58 9.3 6.8 200 mT 200 mT 162 62 10.5 7.6 Magnetic treatment with 200 mT for 1 hr showed 16% increase in grain yield than control
Variety Maintenance• Follow strictly the well defined system of variety purification and maintenance: an essential component between the variety release and seed production• Identify newer areas for quality seed production: compact area, seed zone concept• In case of licensing insist on replacement of Breeder seed / Source seed after every 2 – 3 years in case of CP/ SP spp.
Quality standards• Developing quality evaluation protocols, which are more precise and cost effective• Revision of protocols and standards tomeet the needs of emerging technologies• Generation of data to rationalise standards• Generation of database to apply DNAFP for purity testing• Generation of database for disease management
Relook into Seed Certification Standards1. Rationalise quality standards Legal norms to qualify2. Develop seed quality standards for • Genetic identity • Physical purity• Horticultural spp. (seed • Germinability and planting materials) • Freedom from seed-• Organic seeds borne pathogens• Transgenic seeds
Capacity Building• For seed production through contract farmers : regional agricultural universities and other institutions can build farmers’ skill and employment.• Training farmers to upgrade quality of farm-saved seed which still contributes ~70% of all seed used
HRD and infrastructure development• To have Seed Testing Labs adequately equipped with facilities and trained personnel aware of latest technologies• Establishment of Regional Referral Labs• Close collaborations of ISTA• Regular training programmes for seed analysts ( Specialised Diploma courses )