Thidiazuron and many nitroguanidines (for example, AC239,604 and AC243,654) act as cytokinins similar to kinetin in many bioassays. Potato tuber initiation effects by thidiazuron, and AC239,604 and AC243,654 have not been investigated. These compounds were compared with kinetin for tuber initiation on nodal segments in vitro under short and long photoperiods. Potato plantlets from "Atlantic" tubers were grown in vitro under 16-h days on Murashige-Skoog (MS) medium with 2.5% sucrose. After 2 months, nodal segments were removed and cultured on MS medium containing 6% sucrose and a test compound. Half the nodal segments remained under 16-h days (long photoperiod) and half under 8-h days (short photoperiod). Kinetin was added to the MS medium at 2 mg/L. The test treatments were 0.1 mg thidiazuron/L, 0.01 mg AC239,604/L, and 1.0 mg AC243,654/L, Stolon number and length, root length, stem length, time to microtuber initiation, and microtuber size and number were recorded at 5-day intervals up to 80 days after culture. Thidiazuron behaved much like kinetin in promoting the percent of nodal segments producing stolons and inhibiting the growth of stems and roots under both long and short photoperiods. Thidiazuron and kinetin delayed the onset of tuber initiation and lessened tuber production compared with untreated nodal segments under long days. Under short days, thidiazuron and kinetin increased the rate of stolon elongation, hastened tuber initiation, and increased tuber production. The two nitroguanidines were not as active on stolons, roots, and stems as kinetin. But, under long days, AC243,654 and, to a lesser extent, AC239,604 increased microtuber production without changing the time to tuber initiation. Under short days, the nitroguanidines, as with kinetin, also hastened the onset of tuber initiation but did not increase the number of microtubers produced. Thidiazuron acted like kinetin, promoting tubers under short days, but the nitroguanidines acted differently, promoting tuber production primarily under long days.

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To determine the influence of gibberellic acid (GA3) and 6-furfuryl aminopurine (kinetin) concentrations alone and in combinations on in vitro tuberization of potato, nine treatments consisting of combinations of gibberellic acid and kinetin at three levels of concentration (0, 2, and 5 mg·liter–1) were included in Murashige and Skoog medium supplemented with 6% sucrose. Four single nodes of in vitro plantlets from Solanum tuberosum L. cultivar Atlantic were placed into each magenta box. All magenta boxes were arranged in a randomized complete box design with five replications and cultured under a short photoperiod condition (8 h light/16 h dark). Gibberellic acid strongly inhibited tuberization when used alone or with kinetin, whereas kinetin induced tuberization at both 2 and 5 mg·liter–1. Although tuberization was initiated in the absence of kinetin because of the high concentration of sucrose and short photoperiod, the presence of kinetin accelerated the in vitro tuberization process of potato.

Nowadays diploid einkorn wheat (Triticum monococcum L. ssp. monococcum), widely cultivated in the Neolithic age, has been reconsidered as the valuable genetic resource for breeding and organic farming due to its high resistance to pests and diseases, adaptation to harsh climates, ability to provide acceptable yields on poor soils even with low/without inputs and high nutritional values. In this research, local 45 cultivated einkorn lines, selected from 500 single rows planted by each single spikes collected from total 50 farmers’ fields in 34 villages of Kastamonu/Turkey, were evaluated in terms of their morpho-agronomical traits and nutritional characteristics during two sowing seasons, autumn 2017 and spring 2018. Einkorn lines sown in two different seasons showed significant variations for heading time, plant height, lodging susceptibility, spike length, number of spikelets per spike, gross grain yield, amount of glume, single kernel weight, kernel diameter, hardness index, grain protein content and the color (a, b, L) values of flour. Furthermore, most of the correlation coefficients between these characteristics were found to be significant. All lines showed “facultative” growth habit, flowering well when sown both in autumn and in spring. Although lines sown in autumn had more yields, the same lines sown in spring provided higher grain quality and more resistance to lodging due to having shorter stems. In order to enable sustainable future use of einkorn, further research is suggested for reduction of plant height to avoid lodging and improvement of grain yield to compete with modern high yielding wheat cultivars.

The secondary metabolites synthesized by plants are economically important chemical compounds in the agricultural and industrial areas such as food, perfumery and pharmaceutical sectors. In recent years, attempts for their production by in vitro plant cell and tissue cultures have been accelerated considerably. Colchicine, the principle secondary metabolite of Colchicum autumnale L. and Gloriosa superba L., is an important alkaloid that has poison effect used for treatment of various diseases and plant breeding studies. Presently, colchicine has been produced by using the seeds of C. autumnale L. and the tubers of G. superba L. through different chemical extraction methods. Applying in vitro plant cell and tissue cultures together with metabolic and genetic engineering techniques, large-scale production of colchicine can be achieved from the above two plant species.