Produksi Bibit Kelapa Kopyor True-to-type Melalui Teknik Kultur Embryo

Kopyor is one of the most valuable germplasm in Indonesia. However, the production of true-to-type seedlings with 100 % kopyor nuts is still limited because the nut would not germinated naturally. The only technique available to solve the problem is by using embryo culture technique. However, the technique is limited especially on the low of success rate after acclimatisation step (less than 40 %). Therefore, we report a new breakthough technique for producing kopyor seedling using embryo culture technique especially on acclimatisation step. Our results showed that the best acclimatisation step could be done by culturing 4-month old seedlings in a culture room with 14 hour light with intensity around 1400 lux and 10 hours in the dark. Seedlings were cultured for three months in mini growth chamber with 95 % relative humidity level and temperature around 26 to 28 0C. The survival rate after acclimatisation step on the seedlings with full root was more than 95 %, while for the seedlings without root was c.a 90 %. The acclimatized seedlings then underwent to screenhouse for 1 year befor being field planting. Up to now, more than 170 seedlings of Kopyor have been transfer to the field for developing seed garden of Kopyor in Purwokerto, Indonesia. In the future, creating a breeding program to produce hybrid of Kopyor will be useful for poverty reduction programmes in Indonesia

Cryopreservation of coconut (Cocos nucifera L.) : the influence of embryo maturity upon rate of recovery and fidelity of seedlings

The genetic diversity of coconut (Cocos nucifera L.) is being lost due to a combination of pest and disease attack and natural disasters. Consequently, there is a need to undertake germplasm conservation before further loss occurs. Since coconut has a large, recalcitrant seed (sensitive to desiccation), it cannot be stored in traditional ways using a seed bank. Cryopreservation is now seen as an important storage approach although available techniques need further improvement. Given the importance of embryo maturity to the success of cryopreservation in other species, the effect of coconut embryo maturity upon cryopreservation success was investigated using two cultivars (Nias Yellow Dwarf and Takome Tall). After cryopreservation, using a new four-step protocol (rapid desiccation, rapid freezing, rapid thawing, and recovery and acclimatization S2 SPEAKER ABSTRACTS for 16 wk in the glasshouse), we found that that embryos isolated from an 11-mo-old fruit gave the highest number of normal seedlings (ca. 28%) when compared to counterparts excised from younger or older fruits. In addition, the results showed that the fruit could be stored for up to 3 wk prior to the isolation of embryos before their performance in cryopreservation was compromised. No morphological and cytological abnormalities were observed in the seedlings recovered from 11-mo-old cryopreserved embryos when compared to their un-cryopreserved counterparts. Genetic and epigenetic testing using microsatellite and global DNA methylation rates could not detect any significant differences between genomic DNA isolated from seedlings recovered from cryopreserved compared to their un-cryopreserved counterparts [S-008]. (Texte intégral

Conservation of coconut (cocos nucifera l.) germplasm at sub-zero temperature

Protocols are proposed for the low (-20°C) and ultra-low (-80°C) temperature storage of coconut (Cocos nucifera L.) embryos. A tissue dehydration step prior to storage, and a rapid warming step upon recovery optimized the protocol. The thermal properties of water located within the embryos were monitored using differential scanning calorimetry (DSC). In the most efficient version of the protocol, embryos were dehydrated under a sterile air flow in a dehydration solution containing glucose (3.33 M) and glycerol (15%) for 16 hours. This protocol decreased the embryo water content from 77 to 29% FW and at the same time reduced the amount of freezable water down to 0.03%. The dehydrated embryos could be stored for up to 3 weeks at -20°C (12% producing normal plants upon recovery) or 26 weeks at -80°C (28% producing normal plants upon recovery). These results indicate that it is possible to store coconut germplasm on a medium term basis using an ultra-deep freezer unit. However for more efficient, long term storage, cryopreservation remains the preferred option

Dehydration improves cryopreservation of coconut (Cocos nucifera L.)

Cryopreservation of coconut can be used as a strategy to back up the establishment of living collections which are expensive to maintain and are under constant threat from biotic and abiotic factors. Unfortunately, cryopreservation protocols still need to be developed that are capable of producing a sizeable number of field-grown plants. Therefore, we report on the development of an improved cryopreservation protocol which can be used on a wide range of coconut cultivars. The cryopreservation of zygotic embryos and their recovery to soil-growing plants was achieved through the application of four optimised steps. viz.: (i) rapid dehydration; (ii) rapid cooling; (iii) rapid warming and recovery. in vitro and (iv) acclimatisation and soil-supported growth. The thermal properties of water within the embryos were monitored using differential scanning calorimetry (DSC) in order to ensure that the freezable component was kept to a minimum. The feasibility of the protocol was assessed using the Malayan Yellow Dwarf (MYD) cultivar in Australia and then tested on a range of cultivars which were freshly harvested and studied in Indonesia. The most efficient protocol was one based on an 8-h rapid dehydration step followed by rapid cooling step. Best recovery percentages were obtained when a rapid warming step and an optimised. in vitro culture step were used. Following this protocol, 20% (when cryopreserved 12. days after harvesting) and 40% (when cryopreserved at the time of harvest) of all MYD embryos cryopreserved could be returned to normal seedlings growing in soil. DSC showed that this protocol induced a drop in embryo fresh weight to 19% and significantly reduced the amount of water remaining that could produce ice crystals (0.1%). Of the 20 cultivars tested, 16 were found to produce between 10% and 40% normal seedlings while four cultivars generated between 0% and 10% normal seedlings after cryopreservation. This new protocol is applicable to a wide range of coconut cultivars and is useful for the routine cryopreservation of coconut genetic resources

Tissue culture and associated biotechnological interventions for the improvement of coconut (Cocos nucifera L.): a review

The present review discusses not only advances in coconut tissue culture and associated biotechnological interventions but also future research directions toward the resilience of this important palm crop. Coconut (Cocos nucifera L.) is commonly known as the 'tree of life'. Every component of the palm can be used to produce items of value and many can be converted into industrial products. Coconut cultivation faces a number of acute problems that reduce its productivity and competitiveness. These problems include various biotic and abiotic challenges as well as an unstable market for its traditional oil-based products. Around 10 million small-holder farmers cultivate coconut palms worldwide on c. 12 million hectares of land, and many more people own a few coconut palms that contribute to their livelihoods. Inefficiency in the production of seedlings for replanting remains an issue; however, tissue culture and other biotechnological interventions are expected to provide pragmatic solutions. Over the past 60 years, much research has been directed towards developing and improving protocols for (i) embryo culture; (ii) clonal propagation via somatic embryogenesis; (iii) homozygote production via anther culture; (iv) germplasm conservation via cryopreservation; and (v) genetic transformation. Recently other advances have revealed possible new ways to improve these protocols. Although effective embryo culture and cryopreservation are now possible, the limited frequency of conversion of somatic embryos to ex vitro seedlings still prevents the large-scale clonal propagation of coconut. This review illustrates how our knowledge of tissue culture and associated biotechnological interventions in coconut has so far developed. Further improvement of protocols and their application to a wider range of germplasm will continue to open up new horizons for the collection, conservation, breeding and productivity of coconut