The use of genetic potential of forgotten plants such as grasspea and arugula is an appropriate strategy for increasing of plants tolerance to environmental stresses. Therefore, in this laboratory study the effects of different levels of osmotic (0, -2, -4, -6, -8, -10, -12 and -14 bar caused by PEG) and salinity (0, 50, 100, 150, 200, 250, 300 and 350 mmol induced by NaCl) stresses were evaluated on germination indices of grasspea and arugula in four separate experiments. Arugula showed a suitable tolerance to osmotic stress, so that its germination percentage and rate at treatment of -10 bar were similar to control. Arugula had 79% germination at osmotic level of -14 bar, but its germination rate at this level was 60% lower than control. In addition, its radicle length until -8 bar and radicle dry weight up to -14 bar were higher than control treatment. However, all levels of salinity stress particularly treatments of more than 100-150 mmol decreased the germination indices of arugula. Germination percentage of arugula in 150 and 200 mmol treatments was 22 and 56% lower than control treatment, respectively. Grasspea had partially suitable tolerance to osmotic stress until -6 bar, but then intensified the reducing trends of its germination indices and finally reached to zero at -14 bar treatment. Moreover, salinity stress especially treatments of higher than 100 mmol decreased all germination indices of grasspea. Overall, arugula was a more tolerant plant especially to osmotic stress; therefore this forgotten plant can be used in agronomic and breeding programs in areas affected by drought stress.

Crop management is an important factor affecting the quality of medicinal plants. Therefore, objectives of our investigation on roselle (Hibiscus sabdariffa L.) were: 1) To identify an appropriate planting method in semi-arid regions and 2) to study crop production under water-deficit conditions using eco-friendly techniques. We specifically investigated the effects of planting methods (direct sowing vs. transplanting) (experiment 1, in a randomized complete-block design), as well as effects of water regimes [irrigation after pan evaporation of 100 mm (normal irrigation) and 200 mm (deficit irrigation)], humic acid application (0 and 4 kg ha ⁻¹) and mycorrhizal inoculation (Glomus versiforme, Glomus intraradices, and control) (experiment 2, in a split-split-plot layout) on certain qualitative indices of roselle. The amounts of total soluble solids (TSS), anthocyanin content, and maturity index for direct seeding were, respectively, 17%, 15%, and 33% higher than those for transplanting, whereas vitamin C content and total acidity for transplanting treatment were, respectively, 17% and 20% more than those for direct sowing. According to data obtained from the average of the three mycorrhizal treatments, normal irrigation combined with humic acid application increased total acidity (0.88 mg.100 g⁻¹), anthocyanins (67.1 mg.l⁻¹), and vitamin C content (2177 mg.100 g⁻¹) over the control (deficit irrigation and no humic acid application, which had lower acidity (0.53 mg.100 g⁻¹), anthocyanins (38.8 mg.l⁻¹), and vitamin C content (1882 mg.100 g⁻¹). Total phenol and anthocyanins content under mycorrhizal inoculation were relatively higher than under control treatment at both levels of irrigation. G. intraradices produced the largest amount of vitamin C (2353 mg.100 g⁻¹) under deficit irrigation. On average, no-inoculation treatment had higher TSS, pH, and total acidity than any mycorrhizal inoculation treatment. Humic acid application and mycorrhizal inoculation, especially using G. intraradices, showed the highest values of anthocyanins (56.9 mg.l⁻¹) and vitamin C (2309 mg.100 g⁻¹) content. Overall, normal irrigation, combined with humic acid application and mycorrhizal inoculation, partially improved the quality indices of roselle.

Purpose: The aim of this study was to investigate the effect of fertilizer type and irrigation scheduling on biomass partitioning in saffron. Research Method: The experimental factors were saffron fertilization (no-fertilizer, cow manure and NPK chemical fertilizer) and irrigation regimes (FI=7200 and DI=3600 m3 ha-1) which were tested during 2015-16 growing season, using a factorial layout. Findings: The weights of roots and leaves had an increasing trend up to 72 and 114 days after first autumnal irrigation (DAFAI), respectively, and then were decreased. Corm production started from 51 DAFAI and its maximum was obtained at DI and chemical or organic fertilizer application. In all combined treatments corm production (maximum rate between 114 and 157 DAFAI) was prior to corm filling (started from 135 DAFAI) and both mentioned indices were higher in DI. The weight of replacement corms per clone in plants that were treated by cow manure and received 7200 m3 ha-1 water, was higher (~10%) than all other treatments. Corm growth rate increased from 50 DAFAI and the maximum value (0.32 and 0.34 g day-1 plant-1 in 56 and 78 DAFAI, respectively) obtained at combined treatment of FI × cow manure. Research limitations: Access to similar scientific references on the topic of research was a limitation. Originality/value: This study was the first research which specifically deals with the allocation of photo-assimilates in saffron and based on its findings, application of 3600 m3 ha-1 water plus cow manure is an appropriate strategy in saffron cultivation during first growing season.

In this study effect of irrigation managements including irrigation after 100 and 200 mm pan evaporation as normal and deficit irrigation respectively was investigated in Roselle plants. Effects of humic acid (including 0 and 4 kg ha-1) and mycorrhizal inoculants (including Glomus versiforme (GV) and Rhizophagus irregularis (RI)) were also studied on growth, yield and mycorrhizal symbiosis index of Roselle plants. Drought stress reduced the amounts of morphological indices and yield components, while mycorrhizal treatment particularly RI inoculation and to a lower extent humic acid application reduced the negative impacts of water deficit on growth and yield of Roselle plants. Both inoculants of mycorrhizal fungi increased the economical yield of Roselle under drought stress condition, where the amount of calyx yield for RI, GV and control in 200 mm pan-evaporation treatment was 130, 127 and 66 kg ha-1, respectively. In addition, the highest root mycorrhizal frequency was obtained at normal irrigation × humic application × RI (95%) and the lowest value was observed at deficit irrigation × no-humic × no-mycorrhizal inoculation (31.6%) treatment. In conclusion, combined effects of experimental factors showed that seed inoculation of plants by mycorrhiza and to some extent application of humic acid are two reliable strategies for Roselle production under deficit irrigation.