Plant height, the number of main branches per plant, time of sex
differentiation, habit of flowering as well as fruiting pattern and yield were studied
using different jojoba clones of about 20 years old. Data showed that:
1- Plant height of the progeny of SF1 attained the highest values after 36-months,
followed by SF3 then TF7. The differences between the three progenies seemed
to be a genetically trait. However, the environmental conditions might also have a
slight effect on p < /span>lant height. Consequently, the progeny population of SF1 proved
to be highly stable against the seasonal variations, whereas both SF3 and TF7
have slightly reacted with the seasonal variations.
2- With respect to the number of main branches per plant, it was found that the
progeny population of SF3 obviously attained the highest values of main branches
at 36 months. The extensive branching of SF3 appeared clearly in the three
seasons as compared with that of both SF1 and TFt regardless the seasonal
effect.
3- As for the time of sex differentiation, the data showed that, among a population of
2650 young plants of jojoba grown under greenhouse conditions (13 months-old),
only 3.7% of the plants commenced flowering and this percentage increased
gradually during the second year to be 25.32% (24 months old plants). Moreover,
the time of flowering varied widely among plants. On the other hand, the number
of male jojoba plants which commenced flowering was always greater than the
number of females.
4- In male and female shrubs of the studied jojoba clones, flowers usually develop at
every other node which was found to be the common habit of flowering of all the
studied males; SM1, SM2 and SM3, and only one of the three studied females;
SF4. Flowers develop at every node in two females; SF1 and SF3. All the studied
shrubs tended to produce both types of flowering habit on the same shrub, but
only one type was always clearly dominant. The habit of flowering appears to be
p < /span>rimarily under genetic control which may be modified by environmental
conditions.
5- The common fruiting pattern in the studied jojoba females was that of a single fruit.
In addition, the percentage of fruits with single, double and triple seeds varied from
90.37 to 96.00% , 3.94 to 9.12% and 0.00 to 0.51%; respectively. Clear
differences were found between clones. As an average for the three years, the
clone SF3 proved to give the highest yield of fruits. Moreover, the yield of the
selected clones varied greatly between shrubs as well as between years. Clone
SF3 attained the same attitude of fruits and produced the highest yield in the three
years of study, with an average of 2258.33 gram per plant as compared with that
of SF1 (433.33 g \ plant.) and SF2 (178.33 g \ plant.). The seasonal performance
of clones differed greatly as well.