In recent years consumers tend to pay ever greater attention to food ingredients looking for foods with favourable compositional characteristics. Researches nowadays aim to find out what role the different vegetable species play in protection of the human organism. Consumption of vegetables and fruits more times a day plays an important role in... this process. The valuable chemical components in plants can eventually be influenced, besides, by environmental characteristics, also by the elements of the production technology applied. Our work aimed to find out what eventual changes occur in the composition parameters of sweet corn (Zea mays convar saccharata Koern.) receiving different NPK fertilizations and top dressed with foliar application of Zn and Mg, destined chiefly for fresh consumption, in response to the treatments mentioned above. The fertiliser rates were compared with the help of the variety Spirit (normal sweet, very early ripening).
Investigations into root strength have assumed particular importance with the emergence of American rootworm (Diabrotica virgifera-virgifera) as the number one pest, mainly as a result of monocultural production. Three treatments were applied in the trial: zero control treatment, treatment "A" (g/m2): 4, 47 N + 7, 89 P205 + 19, 74 K20...and treatment "B"(g/m2): 8, 94 N + 15, 78 P205 + 19, 74 K20. Measurements were made to find out whether the treatments had produced any significant difference between the root strength of the two varieties (normal sweet Puma F I and super sweet Dessert R75 Fl) at the two dates of measurement (tasseling, milk stage) in the year 2003. The treatments with a high phosphorous ratio resulted in an apparent increase in root strength with both varieties. There was a detectable difference in root strength also between the two points of measurement, suggesting that root development had remained stable. The treatments produced significant increase not only in the root strength but also in the yields of both varieties.
Hungary is a country with excellent ecological potentials and with rich traditions in vegetable production. The total vegetable production area comprises about 100 000 ha and annual production amounts to 1.4-1.8 million tons, 75-80% comes from fields and the rest from forcing. Approximately 40 species are produced, but only 20 of them play a do...minant role. The most important ones arc: sweet corn, peas, peppers, watermelon, onions, tomatoes, gherkin, carrots, beans, white cabbage.
40-45% of the total production is processed, 20-30% sold on the fresh market and 30% exported.
Vegetable production is based on rural farms of 1-5 ha average acreage. It provides living for about 70-100 000 families. The low number of producers' organisations is a major setback.
Profitability of vegetable production is rather low. Production costs are high, wholesale prices are depressed.
Vegetables are produced for the industry by contract. Fresh vegetables are sold through local markets (15-20%), the wholesale market (decreasing importance) and direct marketing (35-40%).
Against the self-sufficiency of the country there is a seasonal import of vegetables mainly in winter and early springtime.
Hungarian legal regulations are harmonized with the EU directives, EU standards are accepted and applied, traditionally good market connections and cooperation with several EU countries enable the country to be a partner of EU vegetable growers.
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.
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.