(April 4, 2003 – Updated: September 4, 2006)

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The following are the main distinguishing features of the plan designed for and applied at Fincas de Ambato, as far as the problems described above are concerned:

a) Genetic Material

Out of the great genetic diversity found in the plantation, four genotypes referred to as Ambato 1, Ambato 10, Yuto A and Yuto N were selected. In selecting these clones, the following factors were taken into consideration: total production, production continuity, foliage volume, architecture, dehiscence, frost resistance, vernalization requirements, and resistance to plagues and disease.

The clones were selected out of the genetic material existing in our field, using the so-called “early jojoba selection method” developed by Benzioni et al. (1999) in Israel, and the information obtained from plants of up to 9 years of age planted at neighboring fields, identified and controlled by our own staff.

a 1 ) Architecture of the selected plants

Knowing the clones’ foliage volume allows the early determination of the planting scheme that will best suit each genotype. For instance, at age 6 the Ambato 1 clone is 1,59 m in diameter. A reduction of the originally used planting scheme (5 m x 2 m to 5 m x 1,5 m) leads to faster coverage of the inter-plant space, which also entails a shortening of the time required for natural weed control while increasing the seed yield by hectare over the early years of the project. Even though this caused an increase in the planting costs given the increase in the number of plants used, it also implied a significant reduction in the weed control costs and the time required to reach the plantation’s economic-financial balance.

a 2 ) Frost resistances

The exceptionally low temperature of -7°C. ( Table 4-CJ ) experienced in the morning of June 21, 2000 (equal or lower (-9°C) temperatures need to be traced back to the 1950s) offered an opportunity for the field selection of genotypes resisting extreme minimum temperature levels. Likewise, the number of days with frost in the winter of 2000 largely exceeded the historical means observed since this sort of parameters are measured (1961) at the adjoining airport ( Table 4-CJ ). The four clones currently multiplied by Fincas de Ambato resisted these temperatures with no plant losses and even produced seeds, even though the number of seeds produced varied from one clone to the next.

a 3 ) Vernalization requirements

The selected clones have proven to need medium vernalization, requiring “cold” periods sufficiently long as to cause the buds to open once frost is no longer probable (Table 2-V) . The four clones produced seeds in 1999, when the plantation had already endured the last frost on August 25 (frost probabilities end on August 31 each year), which means that the buds flowered after such date.

Moreover, the four selected clones yielded an outstanding seed production in 2003, after the 2002 winter’s cold season with only 17 days of actual vernalization, which turned out to be the second shortest period at Fincas de Ambato (Table 3-V).up to 30% and 12% warmer than the historical mean for the periods 1961-70 and 1971-80, respectively (Table 5-CJ). This winter thermal restriction did not prevent these four genotypes from receiving the cold required to trigger the flowering process. (For further detailes, see Vernalization).

b) Cuttings

Cuttings are planted, for the most part, in September, even though a small number is also planted in March. Planted cuttings have at least three knots and 6 pairs of "hardened" leaves (already covered by the layer of wax typically found in a jojoba leaf), with the potential required to survive the stress of transplantation to the field.

c) Male Population

Even though the system consisting in sowing male seeds has not been fully eradicated, male clones were also rooted and planted in order to overcome the lack of pollen over the early years of the plantation following the removal of cuttings in November 2000. These clones were selected from neighboring projects at lots where the four selected clones had been planted earlier and were also productive. This allowed to guarantee that the flowers of the female genotypes would be compatible with the pollen of the male clones to be multiplied.

At the same time, a plan was implemented for the purpose of mechanically applying supplementary pollen. This plan is carried out by scientist from the University of Arizona and co-funded by Fincas de Ambato and the State of Arizona, U.S.A. (For further details, see Artificial Pollination.)

d) Plantation Management

The work plan implemented for weed control (mechanic, chemical and manual –the latter two for use during the first two years only) keeps the plantation free of weed, even though in most summer seasons the rainfall levels were largely higher than the historical mean (Table 3-CJ). Ants and Tucu-Tucu (Ctenomys spp.), which cause so much damage to new and adult plants, respectively, were controlled (identifying the anthills and nests and using pesticides to destroy them). Irrigation of adult plants is suspended starting January 1 each year in order to decrease metabolic rhythm, thus decreasing potential frost damage. An extended forecast is used for frost probabilities so that no irrigation will take place until frost risk is over, but as early as possible as regards the historical probabilities for late frosts, so as to extend the vegetative growth period. During frosty nights, newly transplanted seedlings are watered –this is an effective protection system- and autumn planting is restricted to the first days of March in order to reach the frost period with seedlings that are sufficiently adapted to the field conditions and have a good potential to tolerate freezing temperatures.

The application of these technologies decreased the seedling loss rate to 14% for seedlings planted in years of very cold temperatures as 2000 (-7 °C of extreme minimum temperature, and a total of 13 frost episodes), and to less than 5% in normal years.

e) Specialized Machinery

Owing to the fact that jojoba is a new crop, no standard machinery is available for use under the different practices required for efficient commercial cultivation. The entire set of specialized machinery used at this plantation was designed by Dr. Wayne Coates, and built and tested under his supervision via research and development projects run by the University of Arizona with funding provided by Fincas de Ambato. Such machinery included a pruner, a combine harvester, a harrow, a pollen harvester and a pollen application machine.

f) Produccton

The first exports of seeds produced by Fincas de Ambato were made to the U.S. in 2002. These shipments comprised seeds accumulated over the first production years from lots of different ages, with a great diversity of clones and a very low density of seed producing plants -400 plants/ha or less in virtually all lots. The crop harvested in agricultural year 2002/03 can be viewed as the first commercial crop, with an average yield of 0.250 kg/plant, a maximum yield per lot of 0.685 gr/plant (523 kg/ha) of dry, clean seed. For the difference in yield between these clones and the selected genotypes, please go to Cuttings. .

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