Effect of Harvesting Time for Quality Seed Yield of Fennel
| Main Authors: | M. Ratna, R. Sarker, M.Z. Ali, R. Ara, M.M. Rahman, M.M. kamrozzaman |
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| Format: | Article |
| Bahasa: | eng |
| Terbitan: |
, 2019
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| Online Access: |
https://zenodo.org/record/3270929 |
Daftar Isi:
- Abstract A field experiment was conducted at Spices Research Sub-Centre, Faridpur during rabi season, 2016-17 to find out the proper harvesting stage of fennel both for chewing and seed purpose and to assure best quality fennel both for chewing and seed purpose. The experimental field belongs to high land of Low Ganges River Floodplain (AEZ 12) with clay loam in texture. The experiment was laid out in a Randomized Complete Block Design with three replications. The experiment comprised of seven harvesting stage viz. 30, 35, 40, 45, 50, 55, and 60 days after flowering. The results revealed that different treatments had significant effect on yield and quality attributes of fennel seed. The fennel umbels which were harvested at 35 days after flowering (DAF) were superior to rest of the harvesting stages and recorded maximum sensory Scores and good for chewing quality fennel with seed yield of 1.32t/ha. However, for obtaining maximum seed yield (1.82 t/ha) umbel/seed should be harvested/picked after 45DAF or 50 DAF. Introduction Foeniculum vulgare Mill. is a biennial medicinal plant belonging to the family Apiaceae (Umbelliferae). Essential oil of fennel is used as flavoring agents in food products such as beverages, bread, pickles, pastries, and cheese. It is also used as a constituent of cosmetic and pharmaceutical products (Piccaglia et al., 2001). Herbal drugs and essential oils of fennel have hepatoprotective effects (Ozbeket al., 2003), as well as antispasmodic effects (Reynolds et al.,1982). They are also known for their diuretic, anti-inflammatory, analgesic and antioxidant activities (Choi et al., 2004). It is an aromatic herb, which is also used as a mouth freshener. It also relieves gum disease or toothache. Commercially, a large portion of the crop is also used in restaurant for chewing purpose. People commonly chew fennel seeds after a meal in India, as it helps to digest food and prevents the formation of gas in stomach. Generally, the crop is harvested at different stages of crop development. The highest seed yield and highest volatile oil content was obtained when umbels were picked at full length size of fruits with green colour (Bhatiet al., 1989). Fennel is harvested before it is fully ripe, but sufficiently hard and of greenish or yellowish brown colour (Hikal and Abdalla,1993). Pre mature harvested seeds have higher moisture content which causes microbial infestation and reduces sensory quality of seed. Whereas, late stage harvest i.e. at dry stage impaired seed quality in terms of seed colour, flavour, texture, taste and formation of crude fibre (Bhardwaj et al., 2013). So, it is important to find out the proper harvesting stage of fennel both for chewing and seed purpose and to assure best quality fennel both for chewing and seed purpose. Materials and Methods The experiment was conducted at Spices Research Sub-Centre, Faridpur during rabi season, 2016-17 to find out the proper harvesting stage of fennel both for chewing and seed purpose and to assure best quality fennel both for chewing and seed purpose. The experimental field belongs to high land of Low Ganges River Floodplain (AEZ 12) with clay loam in texture having 7.6-8.1 soil pH. The experiment was laid out in a Randomized Complete Block Design with three replications. The unit plot size was 3m x 2m. The seed of fennel variety BARI Mouri-2 was sown on 17 November in 2016, maintaining 40 cm x 10 cm spacing. In addition to 5 t/ha of cow dung, the crop was fertilized with P35K68S20 B1.5 kg/ha. The entire amount of cow dung, P, K and S were applied during final land preparation. The N was applied with 3 equal splits at 20, 40 and 60 days after sowing. To control foot rot disease, the crop was sprayed with `Bavistin' (Carbendazim) @ 2g/L of water at 30 and 40 DAS. The experiment comprised of seven harvesting stage viz., 30, 35, 40, 45, 50, 55, and 60 days after flowering. The whole plants were harvested as per treatments. Data on plant height (cm), primary branches per plant, number of umbels per plant, number of umbel lets per umbel, number of seeds per umbel let, 1000-seed weight, seed yield (t/ha) were recorded. The collected data were analyzed and mean values were adjusted by DMRT following MSTAT software. The observations on germination percentage, average root and shoot length (cm), vigour index and germination index were recorded as per ISTA procedures (Anonymous, 1996). Therefore, germination index (G.I.) is computed by using the following formula: G.I. = N/d, where, N= number of seedlings emerging on day‘d’ and d= day after seed setting for germination. Vigour index was computed following the method suggested by Abdul – Baki and Anderson (1973) as Vigour index = (Seedling shoot + root length in cm) × percentage of germination. The sensory evaluation (colour, flavour, aroma, texture and taste) was determined by panel of 5 people (2 scientists, 1 scientific assistant,1 office assistant and 1 farmer) based on five point hedonic scale (Amerine et al., 1965). Results and discussion The seed yield as influenced by stage of harvesting are presented in Table 1.Various parameters on yield viz. plant height (cm), number of primary branches/plant,number of umbels/ plant, number of umbellets / umbel, number of seeds /umbellet, 1000-grain weight and seed yield (t/ha) were significantly influenced by varying treatments of harvesting (Table 1). Though plant height, no.of primary branches/plant, number of umbels/plant increased with each delay harvesting, the highest 1000-grain weight (6.033g) and seed yield (1.98 t/ha) were recorded from 45 DAF being statistically at par with 50 DAF (1.827t/ha). The fennel umbels harvested at 45 DAF is due to higher accumulation of dry matter with minimum crude fiber formation in seed thus increasing test weight of the seed significantly. Similar result was observed by Bhardwaj et al., (2010) in fennel. Bhati (1990) also reported increased test weight of seeds harvested at full grown seed turning yellow stage than half length seed in fennel. However, Chewing type fennel is produced by harvesting the umbels 30-40 days after pollination. At this stage size of the seed is just half of the fully developed seeds and then dried in shade. It reduced the yield but gives high net return as compared to crop harvested at full maturity. Crude fibre content at this stage is 11 % as compared to 15% in the normal fennel (Bhatiet al., 1989). On ripening of the fruit, fiber content increased which decreased the quality. Table 1. Effect of harvesting time on the yield and yield contributing characters of fennel during rabi season 2016-17 Treatments Plant height (cm) Number of primary branches/ plant Number of umbels /plant Number of umbellets/umbel Number of seeds/ umbellet 1000-grain weight (g) Seed yield (t/ha) 30 DAF 122.7 c 5.80 d 8.067 f 21.27 d 20.93 d 4.30 d 1.10 c 35 DAF 126.7 c 6.33 cd 11.90 e 21.60 cd 21.87 d 4.73 cd 1.32 bc 40 DAF 133.1 bc 6.66 bcd 16.93 d 26.13 ab 25.93 bc 5.60 ab 1.53 abc 45 DAF 140.3 ab 7.10 bc 20.87 c 29.13 a 30.87 a 6.03 a 1.98 a 50 DAF 142.9 ab 7.36 b 21.83 c 26.40 ab 27.53 b 5.10 bc 1.82 a 55 DAF 149.4 a 7.50 b 24.63 b 25.40 abc 25.00 c 5.06 bc 1.60 ab 60 DAF 149.5 a 8.43 a 26.13 a 24.33 bcd 22.87 d 4.13 d 1.52 abc L. S. ** ** ** * ** ** * C.V. 3.12% 5.05% 4.51% 8.29% 4.33% 5.69% 10.98% L. S. = Level of significance With each delay in harvesting, there was significant improvement in germination (%), root length (cm), shoot length (cm), vigour index and germination index up to 60 days after flowering (Table 2). The maximum germination (98 %), root length (2.96 cm), shoot length (8.27 cm), vigour index (1101.25) and germination index (4.90) were recorded from 60 DAF. Seeds which were harvested early after flowering was immature, under developed and under sized. They might have less stored food material, resulted in less or poor germination due to under developed embryo. However, seeds were bold which were harvested at later stage of umbel development. Such seeds showed better seed germination percentage even as compared with the standard (Raj, et al., 2017). Table 2. Effect of harvesting stage on per cent seed germination and vigour index in fennel Harvesting stage Germination (%) Root length(cm) Shoot length (cm) Vigour index Germination Index 30DAF 70 g 1.96 g 5.30 f 508.3 g 3.55 e 35 DAF 75 f 2.20 f 5.61 e 587.6 f 3.75 d 40 DAF 81 e 2.39 e 6.17 d 693.4 e 4.17 c 45 DAF 87 d 2.56 d 6.65 c 801.3 d 4.31 c 50 DAF 91 c 2.63 c 6.89 b 857.2 c 4.55 b 55 DAF 95 b 2.73 b 8.16 a 1035.55 b 4.75 a 60 DAF 98 a 2.96 a 8.27 a 1101.25 a 4.90 a L. S. ** ** ** ** ** CV (%) 1.47 1.00 1.57 0.37 2.06 L. S. = Level of significance The results indicated that colour, flavour, aroma, texture and taste score of fennel seeds were affected by harvesting stages (Table 3). Freshly harvested seed bearing light green colour with pleasant flavour and good taste with physically complete seed shape with no damaged edges and shriveled corners was recorded score above 4 (Out of 5 marks) and accepted extremely, whereas aged seed dull brown colour with off/ no flavour and tasteless with broken edges and shriveled corners showing complete loss of seed shape was given score below 2.0 (Out of 5 marks) and rejected extremely. Umbels harvested at 35DAF were found to have superior colour, flavour, aroma, texture and taste score compared to other harvesting stages. The umbel harvested at 35 DAF stage recorded highest score for colour (4.34), flavour (4.4), taste (4.5) and texture of seeds (4.3) as compared to other stages of harvesting. This can be attributed to the fact that the seeds had maximum bright green colour, good flavor and highest dry matter with minimum fibre content at 35 DAF stage of harvesting. After 40 days of anthesis, the crude fiber was higher than optimum rendering it unfit for chewing purpose. These results are in conformity with the results of (Tiwari and Agarwal, 2004). Umbels harvested at 45 DAF demonstrated highest length of seed (9.62 mm), whereas highest width (2.58 mm) was reported when umbels were harvested at 35 DAF. Harvesting after 50 DAF stage leads to the translocation of stored nutrients for new umbels formation and then seeds shrunk, deteriorating the sensory quality of the seeds (Bhardwaj et al., 2010). Table3. Effect of harvesting stage on quality parameters of fennel during rabi season 2016-17 Treatments Color (Out of 5 marks) Aroma (Out of 5 marks) Taste (Out of 5 marks) Texture (Out of 5 marks) Length (mm) Width (mm) 30DAF 3.4 3 3.6 3 8.47 2.48 35 DAF 4.34 4.4 4.5 4.3 8.89 2.58 40 DAF 3.82 3.7 3.9 3.54 8.90 2.56 45 DAF 3.7 3.4 3.2 3.25 9.62 2.55 50 DAF 2.4 2.3 2.5 2.7 9.55 2.53 55 DAF 1.98 2.06 2.2 2.5 9.51 2.45 60 DAF 1.8 1.8 1.2 1.9 9.48 2.38 Thus, the umbels when harvested at 35 days after flowering, the seed yield of 1.32 t/ha was significantly lower than the other treatments but obtained with acceptable fiber content and good attractive colour, aroma, taste and texture of seeds and gives better chewing quality fennel. The umbels harvested at 45 DAF give higher seed yield (1.98 t/ha) which was statistically similar with 50 DAF, 55 DAF and 60 DAF and there was significant improvement in germination (%), root length (cm), shoot length (cm), vigour index and germination index up to 60 days after flowering but after 45 DAF, the other quality parameters viz., colour, aroma, taste and texture deteriorate drastically which may lead to lower consumer preferences. Conclusion It may be concluded that for obtaining better chewing quality fennel with optimum fiber content the umbels/seeds should be harvested/picked 35 DAF and for obtaining maximum seed yield umbels/seeds should be harvested/picked 45DAF/ 50 DAF.