Propagation of Makapuno coconut by tissue culture technology

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Source: https://nongnghiep.vn/nhan-giong-dua-sap-bang-cong-nghe-nuoi-cay-mo-te-bao-d345218.html

Tra Vinh University said that the school scientists have successfully researched the method of breeding Makapuno coconut by tissue culture technology.

Overcoming the limitation in the propagation of Makapuno coconuts

Makapuno is one of the coconut varieties with high economic value. It is known as a specialty of Tra Vinh province. This species of coconut has thick flesh, high oil and nutrition, and a characteristic aroma. However, due to its genetic characteristics, the maintenance and propagation are prone to hybridization, making it challenging to select seedlings that retain good characteristics.

Makapuno coconut is a specialty with a high economic value in Tra Vinh province.
Photo by Minh Dam

On June 14, 2017, the Ministry of Science and Technology agreed to carry out the project “Research on propagating coconuts by tissue culture technology and intensive farming techniques for tissue-cultured varieties.”

The project with a total budget of 10.5 billion VND was carried out by researchers from Tra Vinh University. Dr. Pham Thi Phuong Thuy –  Deputy Head of the Science and Technology Department (Tra Vinh University) and Assoc. Prof. Dr. Pham Van Dong – Institute of Agricultural Genetics were the project leader, with support from lecturers of the Faculty of Agriculture and Fisheries (Tra Vinh University). The project aimed to research and apply tissue culture technology, combined with farming methods, to conserve, store, propagate, and develop some coconut varieties with high economic value, serving the agricultural restructuring and rural development program in Tra Vinh province.

The tissue culture method allows the regeneration of Makapuno seedlings and helps maintain this variety more efficiently. This propagation technique is the most optimal method to increase the ratio of wax coconuts in each bunch to 80 – 100%.

Dr. Pham Thi Phuong Thuy said: “Currently, the project has grown a garden of elite Makapuno palms from sexual embryos with an area of ​​5ha at Tra Vinh University. In addition, the process of breeding Makapuno coconuts by sexual embryo culture techniques has a success rate of 55%.”

Researchers who carried out the project also created callus in vitro of some coconut varieties with high scientific and economic value in Vietnam, such as Makapuno (Dua Sap) and Thai fragant coconuts (Dua Dua), to be used as materials for the production process of pre-embryonic cells – embryonic callus; thereby, creating pre-embryonic callus – embryonic callus cells (clonal embryo, somatic embryo) from callus coconut, regenerate coconut palm from embryonic callus of coconut (clonal coconut – in vitro) and establish a process to grow and take care of cloned coconut palms – in vitro in a net house or nursery.

Propagation of Makapuno coconuts by tissue culture technology
Photo by Minh Dam
For Makapuno palms grown by traditional propagation methods, the rate of wax coconuts is only < 25%, while with dwarf Makapuno varieties, the rate is 20 – 40%. The method of sexual embryo culture was to use sexual embryos from wax coconuts to culture in vitro in an artificial condition. This method produced the seedlings with a wax ratio possibly reaching 100%.


The rate of wax coconut
could reach 100%

According to Dr. Pham Thi Phuong Thuy, after 5 years of implementation, the project has achieved outstanding results in embryo and tissue culture.

For tissue culture, the project has determined the optimal media and tissue samples used to create coconut callus and the medium for creating coconut pre-embryonic cells; pre-embryonic cells that differentiate into asexual embryos; and medium for clonal embryonic and rooting.

100% of plants survived after 1 month. After 3 months, the rate of plants having young leaves reached 72.9% on TS2 potting media (100% Sphagnum Peat Moss) with a mixture of coconut fiber at a ratio of 1:2. The project created 300 seedlings in vitro of Makapuno, 300 seedlings in vitro of Thai fragant coconut, 200 Makapuno seedlings outside the nursery and 200 Thai fragant coconut seedlings outside the nursery.

The process of creating a coconut palm from the embryonic callus of Makapuno is fully implemented. The research created coconut palms from cloned embryos planted in an appropriate substrate. It is valuable research that needs to be encouraged. At the same time, the rapid in vitro multiplication of Makapuno coconuts through the embryogenesis stage has been accepted as a valid patent application by the National Office of Intellectual Property.

Makapuno coconut from tissue culture technology. Photo by Minh Dam

The process of growing coconut palms from the embryonic callus of Thai fragant coconuts is highly appreciated for the variety of experiments. It is an important basis for developing the research process, quality, and volume to meet the order requirements.

With the above results, on November 18, 2022, the Science and Training Council of Tra Vinh University established a committee to evaluate and accept the grassroots topic with 100% of the votes. The project’s success has great potential to put into large-scale seedling production and complete the planting process, helping to create high-quality Makapuno and Thai fragant coconut products for domestic and export demand.

Dr. Pham Thi Phuong Thuy added: “Currently, the method of tissue cultivation produces the same generation of seedlings from a genetic perspective. Only coconut palms are propagated by sexual approaches. Each individual is genetically different. The aim of this study was to produce seedlings that were similar in genetic perspective to have uniform populations in terms of quality and yield. The application of tissue culture technolody to produce coconut varieties is an urgent need that the whole world has been unable to do for a long time.”

The project product has 500 tissue-cultivated wax coconut palms and 500 tissue-cultivated palms of Thai fragant coconuts. However, the author also said that up to now, the multiplier of this method on Makapuno is still low, the highest has only reached 30. Therefore, in the upcoming time, the authors will conduct research to improve the coefficients of this method. The higher the multiplier, the lower the production cost.

The project is expected to continue the implementation of phase 2 which is completing the process of multiplying the nursery stage and assessing the adaptability of tissue-cultivated Makapuno and Thai fragant coconut varieties in the Mekong Delta. In particular, the project’s products are 5ha wax coconut garden. The Rector of Tra Vinh University signed the decision to establish the Project Management Board and at the same time approved the project “Taking care, exploiting and preserving the products of the ministerial-level scientific research – The garden of elite palms of Makapuno” with a total profit of more than 2.6 billion VND in 5 years.

A wax coconut garden has a wax fruit rate of 90%, thanks to embryo cultivation technology. Photo by Minh Dam.

This garden is a place to supply Makapuno and Thai fragant coconut seedlings as standard materials for the propagation and production of high-quality seedlings, meeting the needs of people inside and outside the province. At the same time, it is a place to preserve, visit and conduct relevant studies on wax coconut trees, promoting local socio-economic development.

Currently, the price of Makapuno in the garden is from 80,000 – 150,000 VND/one coconut, sometimes increasing to 160,000 – 170,000 VND/coconut in festive seasons, 10-20 times higher than the original coconuts, or Strawberry coconuts (Dua Dau). With dense flesh, high oil and nutritional content, and a characteristic aroma, Makapuno is used to process food (ice cream, cake, candy), beverage, and cosmetics, for economic efficiency, 10-20 times higher than the original coconuts.

Coconut is the only plant species that uses sexual or incubating methods for propagation. Therefore, coconut is very easy to hybrid, making it difficult to choose seedlings that keep its good characteristics.

Tissue culture technology is a method of maintaining and culturing plant cells, tissues or organs under sterile conditions, carried out under conditions of nutrient-rich media with defined ingredients. The ability to regenerate abundant and high-quality seedlings.

By My Nhien