Researches regarding extractable glyphosate residues from different soils

GLyphosate (N-phosphonomethyl-glycine) is a systemic, broad spectrum herbicide effective against most plant species, including annual and perennial species and is one of the world's most widely used herbicide. To glyphosate applied treatments, a part of active agent comes in contact with soil surface, adsorbing to soil compounds, while another part remains in soil solution. The adsorbing to soil compounds represents a feat importance conditioning the herbicide presence in soil solution and so, his availability to degradation and dispersion in the environment. In this paper work, the extractable glyphosate residues from soil solution have been determined through HPLC-FLD. Substrates used were Black Chernozem, Typical Gleysoil, Slight Vertisol, with moderate carbonatation. The experimental results indicated that the extractable glyphosate residue fractions from soil diminish (<20%), depending of soil parameters and decrease in this order: Gleysoil, Black Chernozem, Slight Vertisol.

Pheromone trap and population model-based control of the codling moth, Cydia pomonella L., in Romanian apple culture

Like in most parts of the world, the codling moth, Cydia pomonello (L.), is one of the most important pests in apple orchards in the Romanian Banat region. There, the control of this pest is often inadequate and the damage and economic losses are therefore enormous. This lack of control is caused by structural problems such as the absence of an advanced distribution network for phytopharmaceutical products, obsolete spraying equipment and the insufficient exchange of knowledge and expertise of those products and the pest itself between the local research facilities and the apple growers. The purpose of this research project is rather demonstrative, because a change in the Romanian pome culture's attitude is urgently needed. Pheromone trapping and the computerized population model RIMpro Cydia, which predicts important phenological events such as adult flight and egg hatch, were used to determine the optimal spray timing. These modern pest management techniques would not only minimize pressure on the environment, but also on the income of the Romanian apple grower, for whom phytopharmaceuticals are a high-priced investment. In July 2006 a comparative study between the supervised pest control program using Calypso, Runner and Reldan, all easily obtainable and commercially available insecticides in the region, and a conventional Romanian management programme was conducted. The control plot and the two test plots were all three located in a high codling moth pressure orchard in Timişoara. In the control plot 9,44 % of the fruits were damaged by codling moth larvae. In the plot containing the trees that were treated according to the traditional Romanian management programme 5,56 % damage was recorded, while the supervised management plot showed only 1,1% damage. Additionally damage was measured in another orchard in Periam, about 60 km away from the other plots. There, an intensive control program using Reldan, Calypso, Actare, Karate and Insegar was applied and damage measured only 0.2%. While at first glance that approach seems most efficient, it has to be noticed that it used twice as much insecticide treatments as were used in the supervised control program. Furthermore, 1 % damage is suggested by most references as being the economical threshold for treatments. The results of this comparative study clearly show that supervised codling moth control proofs to be the most profitable. Starting from August the same year, all of the control programmes in Timişoara were stopped. Therefore the second and possibly the third generation of codling moth larvae could develop freely. In the plot which was earlier sprayed according to the warnings of RIMpro Cydia and the pheromone trap this resulted in 27.5% damaged fruits during harvest in September. In the control plot damage reached 60.95%. These results highlight the necessity of the development of an efficient codling moth control program. Once that program is fine-tuned it should be presented to the local apple growers in order to give the Romanian pome culture a boost.

Management of apple scab (Venturia inaequalis) in Romania based on electronic warnings

Apple scab, Venturia inaequalis (Cke) Wint., is a major problem in Romanian apple orchards and is responsible for serious economic losses. The purchase of spraying equipment and phytopharmaceutical products is very expensive in comparison to the income of local apple growers. This is one of the reasons why reduced fungicide sprayings are becoming more and more important. That's why a project was started to investigate the influence of West-European control measures and to improve interaction between local apple growers and research facilities. This experiment took place in an orchard of the university of Timisoara (USABT), where occurrence of apple scab was very high, and in a well managed commercial orchard, both in the Banat region. In July 2006, a comparative study between a traditional Romanian management program, a calendar-based program and a computerized weather-based management program was conducted. Four test plots were taken. The sprayments in plot 1 happened according to the integrated computerized model. No sprayings took place in plot 2. In plot 3 were some sprayments done with sulphur according to the traditional Romanian program. The sprayings in plot 4 were done following a calendar-based spraying program. The products that were used for the sprayments were all easy to obtain in Romania such as dodine (Sillit flow), dithianon (Delan flow), difenoconazole (Score), pyrimethanil (Scala), metiram (Polyram), kresoxim-methyl (Stroby). The occurrence of scab in plot 1 was very low in comparison to the other plots. Analysing the data, on average, the treatments done in plot 1 caused about 50% less damage than the traditional sprayings. This indicated that with a relative small amount of well timed sprayings a enormous amount of damage can be prevented. A calendar-based management program seems to be less effective (more sprayings needed and the results are worse). These results also emphasize the importance of the development of an adequate apple scab management program that should be presented to local apple growers.