In this research, the effect of foliar spraying of wood vinegar on the growth and biochemical traits of cucumber seedlings in different culture mediums in a factorial experiment in a completely randomized design with three replications was investigated. This experiment was carried out in the spring of 2022 in a research greenhouse at the University of Jiroft. The test factors include two types of culture media (75% cocopeat + 25% peat moss and 75% palm peat + 25% vermicompost) and 5 combinations of wood vinegar (control, oak wood vinegar 0.5 and 1% and wood vinegar Pistachio 0.5 and 1%). The results showed that seedlings grown on palmpeat + vermicompost had maximum values for the fresh and dry weight of roots and shoots, root length, photosynthetic pigments, and auxin. Spraying pistachio wood vinegar at 0.5% and 1% on cocopeat + peat moss and palmpeat + vermicompost substrates, respectively, led to the highest value of root weight. Using 1% pistachio wood vinegar on cocopeat + peat moss substrate increased the root fresh weight (29.1%), the shoot dry weight (13.8%), and the ratio of shoot dry weight to root dry weight (28.4%) compared to the control. Using 1% oak wood vinegar on palmpeat + vermicompost substrate increased the root length (51.9%), chlorophyll b (13.8%), auxin (24.7%), and the total phenol (21.7%) compared to the control. Ultimately, this research suggested that using 1% oak wood vinegar on palmpeat + vermicompost substrate can produce optimal results for the production of cucumber seedlings.

Aim of this study was the application of some organic materials in soil to improve pot marigold plant (Calendula officinalis L.) tolerance to drought stress. Experiment was performed as factorial based on a completely randomized design with three replications. Treatments were consisted of 100% of pot volume soil (control), 1 and 2 g kg-1 nano-potassioum fertilizer, 30% of pot volume cocopeat (v/v) + 70% soil, 30% of pot volume palmpeat + 70% soil and 30% of pot volume madder plant residues + 70% soil in three levels of drought stress (40, 60, and 80% of field capacity). According to the results, with increasing the drought stress, growth parameters were significantly decreased. The highest plant height (14.3 cm), leaf number (70.3), fresh and dry weight of shoot (79.2 and 11.1 g respectively) and roots (34.06 and 9.3 g respectively) were obtained in interaction of madder plant resideue and 60% field capacity drough stress treatment. In severe stress (40% field capacity), plants in medium with palm peat showed the lowest height (7 cm), leaf number (11.6) and crown diameter (10.1 cm). Generally, results showed that madder plant residues with compared to other treatments increased pot marigold resistance to drought stress. Regard to low cost, high moisture keeping and high porosity of madder plant residues, it could be as a suitable substance in arid land to reduce water consumption.

The word biostimulant was apparently coined by horticulture specialists for describing substances promoting plant growth without being nutrients, soil improvers, or pesticides. The use of fresh seaweeds as a source of organic matter and as fertilizer is ancient in agriculture, but biostimulant effects have been recorded only recently. Chemical elements that promote plant growth and may be essential to particular taxa but are not required by all plants are called beneficial elements. The two main beneficial elements are Se and Si, present in soils and plants. Many effects of beneficial elements are reported by the scientific literature, which promotes plant growth, the quality of plant products, and tolerance to abiotic stress. This includes cell wall rigidification, osmoregulation, and reduced transpiration by crystal deposits, thermal regulation via radiation reflection, enzyme activity by co-factors, plant nutrition via interactions with other elements during uptake and mobility, antioxidant protection, interactions with symbionts, pathogen and herbivore response, protection against heavy metals toxicity, plant hormone synthesis and signaling. This study aimed to investigate the effect of different culture media and foliar application of some biostimulants (silicon, selenium, and seaweed extract) on growth characteristics and yield of tomato (cv. Dafnis) under hydroponic condition.

This study was a factorial experiment based on a completely randomized design with two factors of culture media (50% cocopeat + 50% perlite and 50% palm peat + 50% perlite) and foliar fertilizer application (control, concentration of 10 and 20% of seaweed extract, 25 and 75 mg/L sodium silicate and 4 and 10 mg/L sodium selenite) were applied in four replications.

This experiment showed that each of the main factors significantly affected the growth characteristics except stem diameter, number of leaves, and leaf area. There was no significant difference in terms of yield and yield components between palm peat + perlite with cocopeat + perlite. It was also found that foliar application of seaweed extract, silicon, and selenium significantly improved yield and yield components compared to the control treatment. So that among the studied treatments, the highest increase in yield was obtained with the application of 20 % concentration of seaweed extract as well as 75 mg/L sodium silicate.

In general, palm peat in combination with perlite can be used as a suitable media in hydroponic cultures. Also, foliar application of seaweed (20 %), silicon (75 mg/L), and selenium (10 mg/L) had positive and significant effects on vegetative growth and yield of tomato and can be recommended in commercial tomato greenhouses.