Minimize seed deterioration during it’s storage of orthodox or recalcitrant seed.pptx

PG major SEMINAR on minimize seed deterioration during its storage of orthodox or recalcitrant seed ppt file delivered by Pratik Bhankhar (M.Sc. Seed Science and Technology) at C. P. College of Agriculture, S. D. Agricultural University, Sardarkrushinagar.
it contains How to minimize the seed deterioration during its storage.

1. Minimize seed deterioration during it’s storage of orthodox or recalcitrant seed Major Guide Dr. H. S. Bhadauria Associate Professor, Department of Genetics and Plant Breeding, CPCA, S. D. Agricultural University, Sardarkrushinagar . COURSE CODE: SST 591 Presented by Bhankhar Pratik D. Reg. No.: 04-AGRMA-02200-2020 M.Sc. (Agri.) Seed Science & Technology Minor Guide Dr. N. V. Soni Assistant Professor, Department of Genetics and Plant Breeding, CPCA, S. D. Agricultural University, Sardarkrushinagar . 1

2. CONTENTS 2

3. Introduction What is seed ? A  seed  is an embryonic plant enclosed in a protective outer covering The  embryo  develops from the  zygote , and the seed coat from the integuments of the ovule Seeds are the product of the ripened ovule , after fertilization by pollen and some growth within the mother plant Seeds have been an important development in the reproduction and success of gymnosperm and angiosperm plants 3

4. Better-quality seed has a higher demand on the market. Seed quality includes many aspects, such as seed purity, seed vigor, seed longevity etc. Seed quality: Potential performance of a seed lot Trueness to variety Presence of inert matter Seed of other crops or weed seed Germination percentage Vigor Appearance Free from disease High-quality seed lots should meet minimum standards for each of these characteristics 4

5. Factors influencing seed storage Biotic A biotic 1.Biotic factors: a. Factors related to seed Genetic make up of seed Initial seed quality Provenance Seed Moisture content  b. Other biotics Insects Fungi Rodents Mis -handling during sampling 2. Abiotic factors: Temperature Relative humidity Seed store sanitation Gaseous atmosphere Packaging material 5

6. Types of seed Dr. E. H. Roberts (1973) divided seeds into 2 groups based on their storage characteristics: Orthodox seed Dried to moisture contents of 10% or less & successfully stored at subfreezing temperatures Under goes maturation and drying on the parent plant prior to shedding can tolerate considerable desiccation and freezing temperature, RH and moisture content of the seed 6

7. Can with stand dehydration without damage Stored in dry state on long term basis and storage life can be prolonged by decrease in moisture content of the seed, storage temperature and RH E.g. Most of the field crops 7

8. 2) Recalcitrant seed Seed which cannot survive desiccation when dry to low moisture content cannot be stored for the longer period Sensitive to chilling or freezing temperature The moisture content of recalcitrant seeds at maturity is in the range of 30 to 70 percent 8

9. Modifying the storage environment is not possible because of hydrated seed have <20% moisture content Cannot tolerate desiccation or freezing injury - stored under the moisture content of seed >20% and temp. <15ºC except in few cases it can be stored in media such as sawdust, charcoal, absorbent paper, plastic bag for maintaining viability Indigenous species normally short lives and perish within a week or within few months and have water content of 50-60% E.g. coffee, mango, cocoa, rubber, jack fruit, Neem and oil palm 9

10. Seed deterioration Seed deterioration can be defined as “deteriorative alterations occurring with time that increase the seed’s exposure to external challenges and decrease the ability of the seed to survive” Seed deterioration is loss of seed quality, viability and vigor due to effect of adverse environmental factors ( Kapoor et al ., 2010) Annual losses due to deterioration can be as much as 25% of the harvested crop. It is one of the basic reasons for low productivity ( Shelar et al., 2008) Plants that have originated from deteriorate seed can also reduce growth rate ( Kapoor et al., 2010) 10

11. Types of Seed deterioration Field weathering The deterioration of seed quality, vigor and viability, due to high relative humidity and high temperature during the post-maturation and pre-harvest period is referred to as field weathering (Bhatia et al ., 2010) Deterioration caused by weathering is directly related to seed exposure to adverse conditions, so that the physiological quality is depending on the environmental conditions preceding harvesting (Padua et al ., 2009) 11

12. 2. Harvest and post-harvest deterioration Seed quality is highly affected by harvesting and handling methods Harvest and post-harvest deterioration comprises threshing, processing machinery, seed collection, handling, transporting and drying Mechanical damage is one of the major causes of seed deterioration during storage Large seeded varieties are more sensitive to mechanical damage than small seeds 12

13. 3. Storage Storability of seeds is mainly a genetically regulated character and is influenced by Initial quality of the seed Moisture content of seed Ambient relative humidity Temperature of storage environment Duration of storage and biotic agents These environmental conditions are very difficult to maintain during storage. The seed storage environment highly influences the period of seed survival After planting of deteriorate seeds, seedling emergence may be poor and transmission of pathogens to the new crop may occur 13

14. Mechanisms of seed deterioration 14 Once seed deterioration has happened, this catabolic process cannot be reversed.

15. Factor affecting deterioration Environmental factors during storage :- Temperature, Relative humidity Seed moisture content of seed Biological factors such as fungi, bacteria , algae and insects Other factors Environmental conditions during seed producing stage Seed oil content Storage longevity Mechanical damages of seed in processing Fluctuations in moisture Weathering Nutrient deficiencies Packaging Pesticides Improper handling Drying Biochemical injury of seed tissue can affect vigor of seeds Seed longevity is determined by seed moisture, temperature and seed attributes that are influenced by genetic and environmental interactions during seed maturation, harvesting and storage (Walters et al ., 2010) 15

16. Normally, cryo -preserved materials are not immersed in liquid nitrogen for a variety of practical reasons, but kept in the vapor over liquid nitrogen at about -150°C (Stanwood, 1985) The critical moisture level at which this occurs is called the high moisture freezing limit (HMFL Damage is minimized by reducing the cooling rate to 8°C min or less, by sheathing the cryovials with insulation ( Vertucci , 1989) Cryogenic Storage Theoretically, seed should remain viable for an extraordinarily long time in liquid nitrogen at temperature (-196°C), perhaps hundreds of years remain uninjured, without any specific precautions Cryogenic storage is estimated to cost only one fourth as much as conventional low-temperature (-18°C) storage when averaged over 100 years (Stanwood and Bass, 1981) Minimize seed deterioration ORTHODOX SEEDS 16

17. 2. Hydration-Dehydration Treatments Seed priming involves restriction of growth of imbibed seeds by regulation of water potential, or temperature, for a period of 4 to 15 days followed by redrying Hydration-dehydration treatments are less extreme than priming, and are defined here as increasing Aw to about 0.9 or higher for about one day, followed by redrying Improve survival in field planting, response to vigor tests, repair damage from previous aging treatments ( Dey and Mukherjee , 1986) and reduce lipid oxidation products ( Saha , Mandal , and Basu , 1990) 17

18. 3. Antioxidant Treatment If damage to seeds results from free radical attack (Wilson and McDonald, 1986), antioxidants might be expected to prolong the life of seeds Attempts to infuse water soluble reducing agents into seeds have revealed the effects of the agents to be minor compared to the beneficial effect of water alone ( Basu and Das gupta , 1978) Infusion of lipid soluble antioxidants into seeds using organic solvents has occasionally reduced the rate of aging ( Bahler and Parrish, 1981) 18

19. Moist or Imbibed Storage To be kept moist or at a high level of moisture content. As such they present more problems, especially with pests and diseases To survive when kept in moist conditions, such as in moist media and, in extreme cases and stored in water Rubber seeds immersed in water for a month resulted in 60 percent germination ( Ong and Lauw , 1963) Cocoa seeds for three months in media have sawdust, charcoal, and sand, moistened with water. (King and Roberts, 1982) RECALCITRANT SEED 19

20. 2. Partial Desiccation Technique Moisture content is lowered to 25 percent while others can be dried to a lower moisture level. Hence instead of keeping them moist, attempts have been made to partially dry them, i.e., surface drying Partial drying in air at a temperature of 20°C In the case of rubber, the seeds are processed, cleaned, soaked in 0.3 percent benlate , drained, and then surface dried to a moisture content of 20 percent before storage at 20°C + 3°C 20

21. 3. Controlled atmosphere storage Over the years experts have experimented with storing seeds in various gases but there is not as yet a single successful method for practical application. Other methods have been tried, but with little success. Seeds of cocoa have been sealed in their pods by waxing the entire pod ( Pyke et al. , 1934) After processing and cleaning, it was sealed in a container, but remained viable for barely a month ( Soepadmo and Eow , 1976). Similarly, using carbon dioxide, has reported a slight improvement in the storage life of cocoa seeds to 45 days (Villa, 1962) Rubber seeds in a carbon dioxide atmosphere with similar results. From all these reports, it is unlikely that controlled atmosphere storage will be of practical application in the storage of recalcitrant seeds ( Ong and Lauw , 1963) 21

22. Case study-1 The soybean grains were harvested with moisture content around 18 % and dried until 11.2, 12.8 and 14.8 % moisture content The grains were subsequently stored at the following conditions of relative humidity(%) at different temperature for particular moisture content Influence of different storage conditions on soybean grain quality Brazil Alencar et al . (2006) Moisture content (%) Temperature (°C) 20 30 40 11.2 61.7 67.9 69.4 12.8 73.7 76.7 80.8 14.8 82.7 83.9 85.3 22 Table 1: Equilibrium relative humidity for each combination of moisture content and temperature.

23. Table 2: Sour and damaged grains of soybean stored at temperature of 20, 30 and 40 ºC and moisture content 11.2, 12.8 and 14.8 % for 180 days. Temp. (°C) M.C.(%) Storage period (Days) 45 90 135 180 SR DMG SR DMG SR DMG SR DMG SR DMG 20 11.2 0.5 1.5 0.2 0.9 0.3 1.4 0.3 1.3 0.3 0.5 12.8 0.5 2.2 0.2 0.7 0.3 0.7 0.2 0.5 0.3 0.9 14.8 0.3 1.6 0.3 1.2 0.4 1.2 0.2 0.8 0.4 0.9 30 11.2 0.8 1.7 0.2 0.9 0.4 1.1 0.2 0.5 0.3 0.4 12.8 0.7 1.1 0.3 1.1 0.3 1.1 0.4 0.6 0.3 0.4 14.8 0.8 1.2 0.4 1.2 1.9 4.2 1.3 2.5 2.5 3.6 40 11.2 0. 1.5 0.2 0.9 0.6 1.8 0.2 0.7 0.5 0.8 12.8 0.5 1.2 0.3 1.1 0.5 0.9 5.5 8.1 5.6 8.4 14.8 0.8 1.3 0.4 1.4 5.8 8.6 8.8 11.7 9.1 14.3 23 Brazil Alencar et al . (2006) 23

24. Case study-2 Deterioration of sunflower seeds during storage Brazil Abreu et al. ( 2013) Changes on quality of sunflower seeds, stored in different packaging types and environmental conditions, were investigated The packaging used were multiwall Kraft paper and plastic packaging (with and without vacuum), under cold chamber and conventional storage conditions Two hybrids: Helio 250 (high oil content) and Helio 251 (low oil content) two environmental conditions: cold and dry chamber (constant temperature of 10 ºC; and 40% RH); and conventional storage facility (temperatures varying between 18 ºC and 20 ºC; and RH varying from 50% to 70%) The seeds were stored into two type of packaging: multiwall Kraft paper (25 cm x 15 cm); and transparent polyethylene bags (25 cm x 15 cm x 0.12 μ thick); this last type of packaging was used with and without vacuum Seed quality was evaluated by tests of: germination and accelerated aging Changes in the sunflower seed quality were detected by the enzymatic systems: alcohol dehydrogenase and superoxide dismutase 24

25. Fig.1: Oil content (%) of seeds of the sunflower hybrids Helio 250 (A) and Helio 251 (B) as function of storage periods (0 to 12 months) and storage conditions (cold chamber = CC; conventional storage facilities = CSF; bags of multiwall Kraft paper = MKP; plastic packaging = PP; and vacuum sealed plastic packaging = VPP). Brazil Abreu et al . (2013) 25

26. 26 Fig.2: Germination percentage of seeds of the sunflower hybrids Helio 250 (A) and Helio 251 (B) as function of storage periods (0 to 12 months) and storage conditions (cold chamber = CC; conventional storage facilities = CSF; bags of multiwall Kraft paper = MKP; plastic packaging = PP; and vacuum sealed plastic packaging = VPP). Abreu et al . (2013) 26 Brazil

27. Fig.3: Isoenzymes patterns of sunflower seeds of hybrids Helio 250 (A) and Helio 251 (B) subjected to different storage periods (0, 4, 8 and 12 months) under different packaging and storage conditions (T1 – plastic bag, into cold chamber; T2 – Kraft paper, into cold chamber; T3 – Vacuum, into cold chamber; T4 – plastic bags, under conventional storage facilities; T5 – Kraft paper, under conventional storage facilities; T6 – vacuum, under conventional storage facilities), which have been revealed for the enzyme Alcohol dehydrogenase (ADH) and malate dehydrogenase (MDH). Brazil Abreu et al . (2013) 27

28. The storage under cold chamber conditions was more efficient in maintaining physiological quality of sunflower seeds; and under such environment, the Kraft paper packaging was the most adequate The oil content in seeds decreases over time, regardless of storage condition. The linoleic and oleic acids constituted 80% of the total amount of fatty acids scanned Best results for germination were found for seeds of hybrid Helio 250, stored under conventional storage facility and packaged into plastic bags, with or without oxygen restriction, in relation to seeds packaged into multiwall paper bags Brazil Abreu et al. ( 2013) 28

29. Case study-3 The research work was carried to find out whether through pre storage seed priming okra seed deterioration during storage may be controlled or not Fully maturated okra seed were primed with water, PEG-8000 (Polyethylene glycol 8000) and Mannitol solutions Dry seeds were used as control After treatment, seeds were dried to initial moisture content (11%) And then evaluated at zero storage, three months and six months storage for their unsaturated fatty acids, hexanal and proteins Role of pre storage seed priming in controlling seed deterioration during storage Rahman et al. ( 2013) 29 Pakistan

30. Table 3 : Percent unsaturated fatty acids content of okra seed as affected by pre storage seed priming Priming agent Storage period Mean Percent reduction 0 Month 3 Month 6 Month PEG 61.18 59.19 53.38 57.91 12.74 Mannitol 60.91 56.39 49.51 55.60 18.71 Water 60.13 53.71 42.73 52.19 28.93 Unprimed 61.01 54.20 42.67 52.62 30.06 Mean 60.81 55.87 47.07 Rahman et al. ( 2013) 30 Pakistan

31. Table 4 : Effect of pre storage seed priming on hexanal accumulation (µ g Kg -1 ) in okra seed Priming agent Storage period Mean 0 Month 3 Month 6 Month PEG 0.82 13.33 4.71 Mannitol 1.57 20.33 7.30 Water 2.17 26.66 9.61 Unprimed 2.75 34.33 12.36 Mean 1.83 24.66 Rahman et al. ( 2013) 31 Pakistan

32. Table 5 : Effect of seed priming and storage period on percent protein content of okra seeds Priming agent Storage period Mean Percent reduction 0 Month 3 Month 6 Month PEG 23.35 22.80 21.54 22.56 7.75 Mannitol 22.87 21.82 19.16 21.28 16.22 Water 21.77 20.36 16.91 19.68 22.32 Unprimed 21.52 20.31 16.47 19.43 23.46 Mean 22.37 21.32 18.52 32 Rahman et al. ( 2013) Pakistan

33. Case study-4 The effect of storage temperature and time on total phenolics and enzymatic activity of sapodilla ( Achras sapota L.) Colombia Camargo et al . (2016) The effect of different storage temperatures viz. 6, 10, 15, 21 and 27 °C Storage durations viz.0 to 20 days on total phenolics and enzymatic activity of peroxidase (POD), catalase (CAT), and polyphenol oxidase (PPO). The storage temperatures were 6, 10, 15, and 21 °C for 10 d for each group. After that time, each group of fruit was stored at room temperature (27 °C) to complete 20 d of storage. The fifth group (control sample) was stored at 27 °C for 10 d, after this period, the fruits lost texture and there was a considerable decrease in the concentration of total phenolics compounds. 33

34. Fig.4: Behaviour of soluble proteins of sapodilla (A. sapota L.) fruit stored at different temperatures. Fig.5: Behaviour of total phenols sapodilla stored at different temperatures. Colombia Camargo et al . (2016) 34

35. Fig.8: Polyphenol oxidase activity on sapodilla (A. sapota L.) fruit stored at different temperatures. Fig.7: Catalase activity on sapodilla (A. sapota L.) fruit stored at different temperatures. Fig.6: Peroxidase activity sapodilla (A. sapota L.) fruit stored at different temperatures. Colombia Camargo et al . (2016) 35

36. Case study-5 Maintaining dryness during storage contributes to higher maize seed quality Pakistan Afzal et al. (2017) The performance of Purdue Improved Crop Storage (PICS) bags for maize seed storage during a two-month period Seed moisture content increased in polypropylene bags while it remained constant in PICS bags Maize seeds of cultivar “ Sarhad White” used in this study in CRD design with three replication Root and shoot lengths were measured 15 days after sowing. Germination energy (%) was recorded by counting the number of seedlings germinated the fourth day after the start of germination, Assessment of losses due to insects, aflatoxin contamination 36

37. Moisture content (%) Seed with damaged embryo (%) Germination (%) Germination index (GI) Germination energy (%) Root length (cm) Shoot length (cm) Initial 12.5 - 96 11.50 82.00 8.15 3 PICS bags 12.74 1.89 85.33 11.33 81.75 8.10 3 Polypropylene bags 15.64 33.64 50.00 6.80 50.25 2.67 1.5 Table 6: Moisture content and germination attributes of maize seed stored in PICS bags and polypropylene bags for two months Pakistan Afzal et al. (2017) 37

38. Table 7: Live insect population, weight loss, and aflatoxin contamination of maize seed stored in PICS bags and polypropylene bags for two months Sitophilus zeamais (Live) Tribolium castaneum (Live) Rhyzopertha dominica (Live) Weight loss (%) Aflatoxin B1 ( ng /g) Aflatoxin G2 ( ng /g) PICS bag 8 4 1 3 0.08 0.55 Polypropy-lene bag 1378 16 8 35 0.53 1.13 Pakistan Afzal et al. ( 2017) 38

39. No change in germination was observed in maize seeds stored in PICS bags while in polypropylene bags it was reduced in half when compared to the initial germination Seed stored in polypropylene bags had higher insect damage with a weight loss of 35% while in PICS bags the infestation was minimal with a weight loss of about 3% Higher aflatoxin contamination levels were observed in seeds stored in polypropylene than PICS bags Greater germination losses in polypropylene bags were due to increased moisture content in prevailing high RH storage conditions Pakistan Afzal et al. ( 2017) 39

40. Conclusion Seed osmopriming controlled deterioration during storage as compared to hydropriming and non-priming in okra seed The storage under cold chamber condition and conventional storage facilities within plastic packaging, sealed under vacuum are more efficient on preserving the physiological quality of sunflower seeds Lowering the temperature reduce the activity of phenols and concentration of soluble proteins in sapota seed Storing dry maize seeds in PICS even for couple of months will maintain its moisture content, viability and vigor even in high relative humidity and temperature conditions and no mold growth and insect infestation 40

41. Thank You 41