Evaluation of phytotoxicity of acetic and citric acids using the seed germination bioassay

Fitotoksičnost se smatra čestom pojavom u poljoprivrednoj proizvodnji s kojom se mnogi poljoprivrednici suočavaju zbog nepravilne primjene sredstava za zaštitu bilja ili nepravilne gnojidbe. Uzrokuje smanjenu klijavost, inhibira rast i razvoj biljke te ima druge štetne efekte koji uzrokuju odstupanje od normalnog rasta i razvoja biljke. Može biti uzrokovana primjerice organskim kiselinama koje nastaju razgradnjom inkorporirane svježe organske tvari, a nalazimo ih u biljnim, životinjskim i mikrobiološkim izlučevinama, metabolitima i sl. Navedene kiseline smatraju se inhibitorima rasta usjeva. Cilj provedenog istraživanja bio je utvrditi fitotoksičnost octene i limunske kiseline u sedam različitih koncentracija upotrebom testa klijavosti. Osnovna hipoteza ovog istraživanju je da postoji razlika u fitotoksičnosti octene kiseline i limunske kiseline, te da postoji razlika izmeđutestnih vrsta, u ovom slučaju kres salate i krastavca. Utjecaj kiseline na testne biljke utvrđen je testom klijavosti kres salate i krastavca, a isti je proveden po modificiranoj metodi klijavosti sjemena prema Zucconii sur. (1981.). U svaku Petrijevu zdjelicu s filter papirom na dnu, postavlja se 20 sjemenki krastavca i kres salate te se dodaje 5 mL određene otopine octene i limunske kiseline s pripremljenim rastućim koncentracijama (0,00 mM; 0,10 mM; 0,25 mM; 0,50 mM; 1,00 mM; 2,00 mM; 4,00 mM; 8,00 mM), a kao kontrolni tretman (0,00 mM) koristila se deionizirana voda. Nakon postavljanja sjemenki, Petrijeve zdjelice su u 4 ponavljanja postavljene u kontrolirane uvjete na 25°C tijekom 72 sata. Test klijavosti obuhvatio je sljedeće tretmane: 1. dvije vrste testnih biljaka (kres salata i krastavac) 2. dvije organske kiseline (octena i limunska) 3. 8 različitih koncentracija kiselina. U istraživanju analizirani su sljedeći pokazatelji: broj proklijalih sjemenki, relativna klijavost, broj izdanaka, relativni broj izdanaka, duljina korijena, relativna duljina korijena, duljina izdanka, relativna duljina izdanka i indeksklijavosti. Prema rezultatima indeksa klijavosti indek kres salate iznosi veći je od indeksa klijavosti krastavca. 57 U prosijeku i u oba slučaja, najmanju fitotksičnost (u nekim slučajevim i fitostimulativnost) pokazala je otopina od 1mM, a najveću fitotoksičnost pokazala je otopina od 8mM.Phytotoxicity is considered to be a common occurrence in agricultural production that many farmers face due to improper application of plant protection products or improper fertilization. It causes reduced germination, inhibits the growth and development of the plant and has other harmful effects that cause deviation from normal growth and development of the plant. It can be caused, for example, by organic acids formed by the decomposition of incorporated fresh organic matter, which are found in plant, animal and microbiological secretions, metabolites, etc. These acids are considered to be inhibitors of crop growth. The aim of the study was to determine the phytotoxicity of acetic and citric acid at seven different concentrations using a germination test. The basic hypothesis of this study is that there is a difference in the phytotoxicity of acetic acid and citric acid, and that there is a difference between the test species, in this case watercress and cucumber. The effect of acid on the test plants was determined by the test of germination of watercress and cucumber, and the same was carried out according to the modified method of seed germination according to Zucconi and sur. (1981). In each Petri dish with filter paper at the bottom, place 20 cucumber seeds and watercress salad and add 5 mL of a certain solution of acetic and citric acid with prepared increasing concentrations (0.00 mM; 0.10 mM; 0.25 mM; 0 , 50 mM, 1.00 mM, 2.00 mM, 4.00 mM, 8.00 mM), and deionized water was used as a control treatment (0.00 mM). After seed placement, Petri dishes were placed in 4 replicates under controlled conditions at 25 ° C for 72 hours. The germination test included the following treatments: 1. two types of test plants (watercress and cucumber) 2. two organic acids (acetic and citric) 3. 8 different concentrations of acids. The following indicators were analyzed in the study: number of germinated seeds, relative germination, number of shoots, relative number of shoots, root length, relative root length, shoot length, relative shoot length and index germination. According to the results of the germination index, the watercress index of lettuce is higher than the germination index of cucumber. 59 On average and in both cases, the lowest phytotoxicity (in some cases phytostimulativeness) was shown by the 1mM solution, and the highest phytotoxicity was shown by the 8mM solution