During a four yeas long experiment a simple bee shelterswas found to be a propermethod to increase the size ofmixed natural populations of the early season Osmia cornuta and O. rufa under practical farm conditions. Instead of the number of pesticide applications the earliness of the flowering of the fruit species in the orchards was found to be... themost important factor in the rate of acceptance of reed as nestingmediumby Osmias in the bee shelter. This relationship was negative and highly significant (r = –0.829, p<0.001). This means that much higher acceptance of artificial nestingmedia in bee shelters and consequentlymuch higher population increase of the two early seasonmason bee species can be expected in orchards with early than with late flowering fruit species. Mixed orchards or early flowering orchards surrounded by other orchards falling in bloom later consecutively may also be much favourable to mason bees because they can find continuous food (pollen) supply there for a much longer time during their period of activity than in orchards planted with a single fruit species and being apart from orchards of other fruit species.
In our trial we tried to find out how the time of propagation and transplanting influenced the growing season of sweet corn along with some major properties relevant to quality. The following technological variations were compared with the help of the variety Spirit (normal sweet, very early ripening): transplanted plants with floating row cove...r (with 2 planting dates); transplanted plants with no row cover: direct seeded plants with no row cover. The 21 day transplant growing period reduced the growing period by 16 to 20 days, compared to the technology used in the existing practice of production. Earliness had a negative influence on ear size, nonetheless it is worth while to attempt since the market is not so exacting with new products in the early period. Covering the seedlings in the early season was clearly beneficial, as the floating row cover provided protection for plants against lower night temperatures which are common in this period.
Direct sowing in 16 cm deep trench covered with perforated plastic sheet (for 3 weeks), transplant using, and uncovered direct sowing (control) was tried on 2 locations, with 2 varieties (very early Kecskeméti korai extra, and middle early Kecskeméti SC-370) in Szarvas on loamy soil, and in Kecskemét on sa...ndy soil in 1996 — after a preliminary trial concerning perforated plastic covered trench sowing in Szarvas, in 1995.
The plant height (weekly), the average leaf number/plant, the total leaf area (once), the total yield, the quality of cobs, and the earliness was measured. The results are:
- Kecskeméti korai extra during the first 6 week period the transplanted plants were the highest, but from the 7th week the plants which were sown in trench and than were covered with perforated plastic sheet (for 3 weeks) were the highest.
- SC-370: The transplanted plants were the highest-until the end of plant height development.
The plant height development stopped at the 9th week of the measurement by early, - and stopped at the 10th week by middle early variety. The average leaf number/plant varied between 9,25-10,50 and was not influenced either by variety or by the treatment. The total leaf area was (on 5th of June) the largest by transplanted plants, which was followed by plants that were sown in trench and then were covered with perforated plastic film (for 3 weeks).
- The highest yield was observed by plants, which Were sown in trench, and then were covered with perforated plastic film (for 3 weeks). Transplanted plants followed it.
- Quite the total yield (98,3%) of transplanted Kecskeméti korai extra variety plants were harvested on 4th July. 89% of the total yield was picked up of trench sown and then with perforated plastic covered plants. The harvest of uncovered control started on 15th July. The harvest of transplanted SC-370 plants started 19th July, when more than half of the total yield (57%) was picked. The uncovered control was harvested 29th July.
- The weight and the measure of cobs generally were not influenced by the treatments, but the average weight of the cobs of the transplanted Kecskeméti korai extra plants (0,21-0,18 kg) are less than the, requirement.