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Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir./ Sch. Bip.) synthesizes secondary metabolite pyrethrin, known for its potent insecticidal and repellent activity. The present study was aimed at optimizing the maceration extraction parameters that improve the efficiency of pyrethrin extraction from the dried Dalmatian pyrethrum flower heads. Extraction efficiencies under several conditions were investigated: different solvent types, extraction time, the rotational speed of the stirrer, and the solvent volume. The highest recovery values were obtained with 5 mL of acetone, at the rotational speed of 400 rpm, and the extraction time of three hours. In addition, the extraction efficiency of maceration was compared to that of ultrasound-assisted and matrix solid phase dispersion extraction, both previously optimized for pyrethrin extraction. The extractions were carried out on samples of three natural Dalmatian pyrethrum populations (Krk, Mt. Kozjak, and Senj). Both the total pyrethrin content and the HPLC profile varied between different extraction techniques. Across applied methods, the highest efficiency was observed with matrix solid phase dispersion extraction. Evaluation of the differences between data obtained using different extraction techniques was performed by the Bland-Altman analysis, revealing good agreement between the three methods.

Common bean (Phaseolus vulgaris L.) exhibits a wide range of seed coat colors and this morphological trait is widely used in cultivar identification and assessment of diversity within this species. With an advancement in technology and informatics, new methods of assessing seed color are emerging in addition to traditionally used visual observation. Due to a great variety of color measuring techniques, the evaluation of the agreement between methods is needed prior to using the methods interchangeably. Seed coat color in terms of CIE L*a*b* color coordinates of 100 common bean accessions belonging to five mono-colored landraces was assessed using two methods, colorimeter and Computer vision. The percentage difference between the two methods across all samples for L* color coordinate was 5.81%, for a* color coordinate 23.32% and for b* color coordinate 44.44%. According to Bland-Altman difference plot there is a considerable lack of agreement between the two methods. However, using stepwise discriminant analysis revealed that colorimeter method correctly classified 97% of accessions into their respective landrace, while the classification success of the Computer vision was 99%., Grah (Phaseolus vulgaris L.) pokazuje veliki raspon boja sjemene ljuske te je korištenje ove morfološke karakteristike uobičajeno u identifikaciji kultivara i procjeni raznolikosti unutar vrste. Napretkom tehnologije i informatike pojavljuju se nove metode određivanja boje sjemena uz klasičnu metodu vizualnog određivanja. Zbog velikog broja tehnika određivanja boja, potrebna je ocjena usuglašenosti između metoda prije njihovog kombiniranja ili naizmjeničnog korištenja. Boja sjemena 100 primki pet jednobojnih tradicijskih kultivara graha opisana CIE L*a*b* koordinatama procijenjena je koristeći dvije metode, kolorimetar i računalni vid. Postotna razlika između dvije metode kroz sve uzorke za koordinatu L* iznosila je 5.81%, za koordinatu a* 23.32%, a za koordinatu b* 44.44%. Bland-Altmanov graf razlike pokazuje da postoji značajan nedostatak usuglašenosti između dvije metode. Koristeći postupnu diskriminantnu analizu uspješno je klasificirano 97% primki na temelju podataka dobivenih kolorimetrom dok je klasifikacijski uspjeh računalnog vida bio 99%.

Dalmatian pyrethrum (Tanacetum cinerariifolium /Trevir./ Sch. Bip.) produces pyrethrin which is currently the most important natural insecticide. Due to the growing interest for its use in organic agriculture, the demand for this valuable plant is increasing. However, poor seed germination and inaccessibility of high quality planting material is one of the main constrains for the introduction of Dalmatian pyrethrum into agricultural production. Priming treatments are known to be able to induce rapid and more uniform seed germination, seedling emergence and plant growth and their efficiency was tested on Dalmatian pyrethrum seed. Seed of four natural Dalmatian pyrethrum populations was subjected to hydropriming or osmopriming with 0.2% KNO3 with the aim of determining their effect on germination parameters (germinability, mean germination time, mean germination rate, coefficient of variation of the germination time, uncertainty of the germination process and synchrony of the germination process). The significantly highest(P< 0.05) germinability was recorded for the Biokovo population (27.00%), followed by the population from Šolta (19.67%), Konavle (17.67%) and population from Šibenik (6.67%). Hydropriming for 24h significantly increased the seed germination and germination index (P< 0.05). The treatment with 0.2% KNO3 improved germinability and germination index when compared to control, however, the differences were not significant (P>0.05). As a low-cost, simple and practical, hydropriming can be recommended as an effective method to promote germination performance of Dalmatian pyrethrum seed.