Artificial hybridization techniques in small millets—A review
Small millets are nutri-rich, climate-resilient food and fodder crops. They include finger millet, proso millet, foxtail millet, little millet, kodo millet, browntop millet, and barnyard millet. They are self-pollinated crops and belong to the family Poaceae. Hence, to widen the genetic base, the cr...
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| Format: | Article |
| Language: | English |
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Frontiers Media S.A.
2023-05-01
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| Series: | Frontiers in Plant Science |
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| Online Access: | https://www.frontiersin.org/articles/10.3389/fpls.2023.1112117/full |
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| author | T. E. Nagaraja Nandini C. Sujata Bhat Gazala Parveen S. |
| author_facet | T. E. Nagaraja Nandini C. Sujata Bhat Gazala Parveen S. |
| author_sort | T. E. Nagaraja |
| collection | DOAJ |
| description | Small millets are nutri-rich, climate-resilient food and fodder crops. They include finger millet, proso millet, foxtail millet, little millet, kodo millet, browntop millet, and barnyard millet. They are self-pollinated crops and belong to the family Poaceae. Hence, to widen the genetic base, the creation of variation through artificial hybridization is a prerequisite. Floral morphology, size, and anthesis behavior cause major hindrances in recombination breeding through hybridization. Manual emasculation of florets is practically very difficult; therefore, the contact method of hybridization is widely followed. However, the success rate of obtaining true F1s is 2% to 3%. In finger millet, hot water treatment (52°C) for 3 to 5 min causes temporal male sterility. Chemicals such as maleic hydrazide, gibberellic acid, and ethrel at different concentrations aid in inducing male sterility in finger millet. Partial-sterile (PS) lines developed at the Project Coordinating Unit, Small Millets, Bengaluru are also in use. The percent seed set in crosses derived from PS lines ranged from 27.4 to 49.4, with an average of 40.10%. In proso millet, little millet, and browntop millet, apart from contact method, hot water treatment, hand emasculation, and the USSR method of hybridization are also followed. A newly developed modified crossing method known as the Small Millets University of Agricultural Sciences Bengaluru (SMUASB) method in proso and little millets has a success rate of 56% to 60% in obtaining true hybrids. Hand emasculation and pollination under the greenhouse and growth chamber in foxtail millet with a success rate of 75% seed set is suggested. In barnyard millet, hot water treatment (48°C to 52°C) for 5 min followed by the contact method is often practiced. Kodo millet being cleistogamous, mutation breeding is widely followed to create variation. Most commonly, hot water treatment is followed in finger millet and barnyard millet, SMUASB in proso, and little millet. Although no specific method is suitable for all small millets, it is essential to identify a trouble-free technique that produces maximum crossed seeds in all the small millets. |
| first_indexed | 2024-04-09T13:34:42Z |
| format | Article |
| id | doaj.art-14c2ba86b30946c796954ada2f1c349f |
| institution | Directory Open Access Journal |
| issn | 1664-462X |
| language | English |
| last_indexed | 2024-04-09T13:34:42Z |
| publishDate | 2023-05-01 |
| publisher | Frontiers Media S.A. |
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| series | Frontiers in Plant Science |
| spelling | doaj.art-14c2ba86b30946c796954ada2f1c349f2023-05-09T10:34:44ZengFrontiers Media S.A.Frontiers in Plant Science1664-462X2023-05-011410.3389/fpls.2023.11121171112117Artificial hybridization techniques in small millets—A reviewT. E. Nagaraja0 Nandini C.1Sujata Bhat2Gazala Parveen S.3Project Coordinating Unit on Small Millets, Indian Council of Agricultural Research – All India Coordinated Research Project (ICAR-AICRP) on Small Millets, University of Agricultural Sciences, Gandhi Krishi Vignana Kendra (GKVK), Bengaluru, IndiaZonal Agricultural and Horticultural Research Station (ZAHRS), Babbur Farm, Hiriyur, Keladi Shivappa Nayaka University of Agricultural and Horticultural Sciences, Shivamogga, IndiaProject Coordinating Unit on Small Millets, Indian Council of Agricultural Research – All India Coordinated Research Project (ICAR-AICRP) on Small Millets, University of Agricultural Sciences, Gandhi Krishi Vignana Kendra (GKVK), Bengaluru, IndiaProject Coordinating Unit on Small Millets, Indian Council of Agricultural Research – All India Coordinated Research Project (ICAR-AICRP) on Small Millets, University of Agricultural Sciences, Gandhi Krishi Vignana Kendra (GKVK), Bengaluru, IndiaSmall millets are nutri-rich, climate-resilient food and fodder crops. They include finger millet, proso millet, foxtail millet, little millet, kodo millet, browntop millet, and barnyard millet. They are self-pollinated crops and belong to the family Poaceae. Hence, to widen the genetic base, the creation of variation through artificial hybridization is a prerequisite. Floral morphology, size, and anthesis behavior cause major hindrances in recombination breeding through hybridization. Manual emasculation of florets is practically very difficult; therefore, the contact method of hybridization is widely followed. However, the success rate of obtaining true F1s is 2% to 3%. In finger millet, hot water treatment (52°C) for 3 to 5 min causes temporal male sterility. Chemicals such as maleic hydrazide, gibberellic acid, and ethrel at different concentrations aid in inducing male sterility in finger millet. Partial-sterile (PS) lines developed at the Project Coordinating Unit, Small Millets, Bengaluru are also in use. The percent seed set in crosses derived from PS lines ranged from 27.4 to 49.4, with an average of 40.10%. In proso millet, little millet, and browntop millet, apart from contact method, hot water treatment, hand emasculation, and the USSR method of hybridization are also followed. A newly developed modified crossing method known as the Small Millets University of Agricultural Sciences Bengaluru (SMUASB) method in proso and little millets has a success rate of 56% to 60% in obtaining true hybrids. Hand emasculation and pollination under the greenhouse and growth chamber in foxtail millet with a success rate of 75% seed set is suggested. In barnyard millet, hot water treatment (48°C to 52°C) for 5 min followed by the contact method is often practiced. Kodo millet being cleistogamous, mutation breeding is widely followed to create variation. Most commonly, hot water treatment is followed in finger millet and barnyard millet, SMUASB in proso, and little millet. Although no specific method is suitable for all small millets, it is essential to identify a trouble-free technique that produces maximum crossed seeds in all the small millets.https://www.frontiersin.org/articles/10.3389/fpls.2023.1112117/fullemasculationhybridizationpartial sterile linespollinationrecombinationsmall millets |
| spellingShingle | T. E. Nagaraja Nandini C. Sujata Bhat Gazala Parveen S. Artificial hybridization techniques in small millets—A review Frontiers in Plant Science emasculation hybridization partial sterile lines pollination recombination small millets |
| title | Artificial hybridization techniques in small millets—A review |
| title_full | Artificial hybridization techniques in small millets—A review |
| title_fullStr | Artificial hybridization techniques in small millets—A review |
| title_full_unstemmed | Artificial hybridization techniques in small millets—A review |
| title_short | Artificial hybridization techniques in small millets—A review |
| title_sort | artificial hybridization techniques in small millets a review |
| topic | emasculation hybridization partial sterile lines pollination recombination small millets |
| url | https://www.frontiersin.org/articles/10.3389/fpls.2023.1112117/full |
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