The influence of transplantation time on the physical parameters of tobacco seed from plants meant for seed production
The studies conducted for three years at the Experimental field for tobacco Urziceni. The cultivar used in the experiments was Baragan 185 (a large-leaved cultivar, used for cigarettes of large consumption).
The aim of the studies was to establish the proper time for the transplantation of the plants meant for tobacco seed production, so that the seed obtained would have upper figures of the physical parameters.
Five transplantation times were used, starting on 20 April to 10 May (an interval of 5 days between them).
To satisfy the above aims, the following aspects were analyzed in the field and in the laboratory: the time of flowering and formation of the capsules, the germinative faculty, the germinative energy, the yield of seed per plant and per surface unit, the weight of seed per capsule.
The conclusions were as follows:
- the best time for the transplantation of Baragan plants was end of April (30 April). Transplantation at this time, the plants avoid the late hoarfrosts, and the seed ripens in the best conditions;
- the flowering began in mid June; the favourable weather allowed the browning and the ripening of the capsules in mid September;
- the germinative faculty was over 90%;
- the yield of seed harvested per plant (40 capsules) was of 8 - 12 grams;
- the weight of the seed per capsule was of 0.180 - 0.300 grams. The transplantation times before 30 April were unfavorable for the plants meant for seed production, because more than 50% of the young plants were destroyed by hoarfrost, and retransplantation was necessary.
The transplantation times later than 5 May were also unfavorable because the vegetation of the plants was late. They flowered in the first ten days of August, the seeds could not ripen and their quality was low (germinative faculty of 70 - 74%, a seed yield per plant of 4 - 7 grams).