1. Erzsébet Nádasy – Gábor Wágner University of Veszprém Georgikon Faculty of Agricultural Sciences Erzsébet Nádasy – Gábor Wágner University of Veszprém Georgikon Faculty of Agricultural Sciences DRY MATTER PRODUCTION OF GREEN PEA INFLUENCED BY HERBICIDES

2. INTRODUCTIONINTRODUCTION Green pea is one of the most important vegetables in Hungary. Chemical weed control has an important role in pea growing, because at the beginning of its development pea isn’t able to depress the weeds.

3. Time of sowing considerably determines the weed population of the field. T2 life form weeds can germinate intensively at the same time when pea does. Lately the representatives of T3 life form weeds can cause problem. At the end of vegetation period, after falling down the lower leaves of pea T4 life form weeds can totally cover the field. Weed flora of the pea field

4. Technology of weed control determines weed flora of the field, and the aim of pea growing. Chemical weed control may carry out with: presowing, pre-emergent, post-emergent herbicides Chemical weed control of pea

5. The aim of our experiment was to study the effect of five pre-emergent herbicides with different mode of action on the fresh and dry matter production and growing of a green pea variety.

6. MATERIALS AND METHODS Pot experiment: was carried out in April of 2003 under greenhouse conditions each pot contained 1 kg air-dried soil Twelve pieces of pea seeds were sown into each pot to 3 cm depth. 4 replications

7. Parameters of experimental soil Ramann’s brown forest soil from Keszthely Humus (%)2,05 mineral nitrogén (mg kg -1 soil)23,37 Al-K 2 O (mg kg -1 soil)140 Al-P 2 O 5 (mg kg -1 soil)160 pH-H 2 O7,26 pH-KCl6,48 maximal water holding capacity (mg kg -1 soil)273

8. Examined pea variety Examined pea variety „Rajnai törpe”

9. Herbicide treatments in the experiment

10. Examined parameters We determined four weeks after sowing: fresh mass dry matter production length Statistical analysis was carried out by SPSS 7.5 software. of the shoots and roots

11. RESULTS AND DISCUSSION

12. Fresh mass of shoots of pea due to the herbicide treatments

13. Fresh mass of roots of pea due to the herbicide treatments

14. Dry matter of shoots of pea due to the herbicide treatments

15. Dry matter of roots of pea due to the herbicide treatments

16. Length of shoots of pea due to the herbicide treatments

17. Length of main roots of pea due to the herbicide treatments

18. The plants treated with Pivot developed uniformly, and produced the greatest dry matter, except the effect of double dose on the roots.

19. Sencor 70 WG strongly inhibited dry matter production and growth of pea and caused severe phytotoxic symptoms.

20. The effect of Proponit 840 EC was similar to that of Sencor.

21. Double dose of Stomp 330 also damaged the pea plants, but to a lesser extent than Sencor

22. In our investigation Afalon Dispersion was the other adequate herbicides for weed control besides Pivot.

23. CONCLUSIONSCONCLUSIONS In our investigation Afalon Dispersion and Pivot proved to be the most suitable pre- emergent herbicides for weed control of green pea. “Rajnai törpe” green pea wasn’t sensitive to these chemicals. It is worth to be mentioned that permission of Pivot was cancelled in Hungary last year.

24. Thank you for your attention!