AstroTubers (potato minitubers) are tubers produced by one or two node stem cuttings derived from established tissue culture plantlets, Stem cuttings are made from the tissue culture plantlets after a growth period of 3 to 4 weeks in a phytotron. Repeated stem cuttings can be made from the established plantlets at approximately 3 week intervals. The tissue culture plantlets are replaced annually.
Prior to planting in a rooting matrix, the stem cuttings are treated to enhance root development. The stem cuttings are grown in a phytotron in which a specific environmental regime is programmed to provide the optimum environmental conditions during the different growth stages, from establishment, vegetative growth, tuberization, to harvest. The time from planting of the stem cutting to the harvest of the AstroTuber is 6 to 7 weeks.
AstroTuber Seed Potato Production Process
The harvested AstroTubers are stored at the desired temperature to allow for overcoming dormancy. The AstroTubers can be stored for periods over a year. Sprouting of the AstroTubers prior to field planting can be readily induced by a defined environmental regime in a phytotron. Such a sprouting treatment provides AstroTubers for field planting that promptly emerge and develop a rapidly growing plant canopy.
Shawn Bula of Bula-Gieringer Farms is shown with a representative sample of one hill of FG-1 Tundra seed potato tubers. He said the Tundra seed averaged close to 425 cwt./acre.
The following unique features of the CETS AstroTuber™ (potato minitubers) production technology result in a very efficient system:
- A CETS phytotron allows for AstroTuber production during the entire year, thereby increasing the number of AstroTubers that are produced in a year as compared to greenhouse systems that are subject to hot and cold temperatures which have a negative impact on yields of minitubers. Another significant environmental factor that has an obvious impact on the rate of plant productivity is the daily and seasonal variable light (sun) levels in a greenhouse compared to the constant high light level in a CETS phytotron.
- The environment of the CETS phytotron significantly reduces the potential for foliar disease development during production of the AstroTubers compared to the environment of a greenhouse. Thus, use of the CETS phytoron eliminates the use of chemicals for the control of foliar diseases normally required in a greenhouse minituber production system.
- Use of stem cuttings from tissue culture plantlets for production of the AstroTubers results in significant cost savings compared to systems that use tissue culture plantlets for production of minitubers.undefined
- Use of the CETS proprietary nutrient solution not only optimizes the production of AstroTubers, but significantly reduces the cost of the chemicals used in the nutrient solution compared to the cost of commercially available fertilizers that may or may not support optimum growth, development, and tuberization.
- An LED plant lighting system is more efficient than any other lighting systems that are being used for growing plants. The LED lighting system installed in the CETS phytotrons results from extensive design discussions with organizations that fabricate LED lighting systems. These LED lighting units are expressly designed for growing potato plants during all stages of development from planting to maturity, including tuber initiation and development. The LED lighting units are the most efficient converters of electricity to photons of any lighting system, plus having a longer life than any other light system. Use of LED lighting units results in significant reduction of electrical costs with increased AstroTubers yields.
The fundamental features of AstroTubers (potato minitubers) emanating from the CETS technology result in a superior tuber. The AstroTubers are grown in a proprietary rooting matrix that essentially duplicates the natural field environment and is a vastly superior tuber development environment due to the rooting matrix porosity and presence of high oxygen levels. The developing tuber is a highly metabolic organ that requires availability of high levels of oxygen for effective growth and development. The use of a porous rooting matrix avoids the deliterious hypoxic conditions and their impact on root and tuber growth that are prevalent in other systems used for minituber production.
The periderm forms a protective layer of cells covering the surface of the tuber. This outer tuber layer has perforations called lenticels that allow for exchange of gases and water as well as being an opening for pathogens to invade the tuber. Tubers grown in water or a wet tuber development environment, as is the case in NFT and aeroponic minituber production systems, develop enlarged lenticels that can become “highways” for pathogens to enter the tubers. This characteristic of the tuber is of critical concern regarding field plantings because soil borne pathogens can readily infect the planted tubers having enlarged lenticels and result in death of the plant.
Since AstroTubers develop in what can be termed a normal underground environment, AstroTubers develop a normal periderm layer with normal lenticel characteristics. Thus, AstroTubers can be planted in the field without any fungicide treatment. AstroTubers have been planted in the field for over 10 years without being treated with fungicides and no negative effects have been noted on stand development.
Another important characteristic of the AstroTubers is that they are grown and harvested in way that is similar to normal field conditions. At harvest time, the plant is in a senescent state. This results in physiological maturity of the AstroTubers as part of the senescent process. This contrasts with minituber tuber harvesting in NFT or aeroponic systems where the plants are cultured in a way to prolong the growing process so that the plants do not go into the senescent stage. This results in an “immature” minituber with potential storage and sprouting problems not encountered with AstroTubers. Botanically, the potato is a determinate plant and the NFT and aeoponic systems culture the plant so that it becomes an abnormal indeterminate plant. The CETS AstroTubers production system capitalizes on the natural botanical characteristic of potato resulting in a superior tuber.
Eliminating the possibility of carry over disease infestations
A unique feature of producing Astrotubers in the CETS phytotrons is that the environment in the phytotron does not support dew formation at any time. This lack of dew means that any spores that may be present in the growing area of the CETS phytotron, do not have a source of water on or near the leaf surface in which to germinate and infect the plant. Thus, no fungicides are necessary to control foliar diseases in a CETS phytotron.
The CETS phytotron interior and exterior walls and floor are stainless steel and consequently can be thoroughly sanitized after each harvest. The sanitizing procedures used eliminate any possibility of carry-over disease infestations from one growth period to the subsequent growth period. This feature, plus not reusing the rooting material for subsequent plantings and not recirculating the nutrient solution during the growth period, provides an optimum situation for elimination of the potential for disease infection during the production of disease-free Astrotubers in the CETS phytotrons, compared to NFT systems housed in greenhouses or tunnels.
Actual CETS AstroTuber seed potato production results as documented by a CETS customer.
Year 1 (G-0)
AstroTubers produced in CETS phytotrons.
Year 2 (FG-1)
30 Tissue plants (i.e. “mother” plant starting material) per year yields + 15000 AstroTubers sizes ½” to 1+” produced in phytotrons (64 sqft total).
Year 3 (FG-2)
Field plant one acre with 3 foot row spacing (68 rows per acre) and in-row spacing of 12” (206 plants in each row), requires planting 14000 AstroTubers (68 x 206) and yields a harvest of 350+cwt