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Abstract Purpose An experiment was designed to introduce a substitute for peat, which is used in the production of bedding for the cultivation of ornamental plants and is imported and expensive. For this reason, the usability of peanut shells and Azolla, whose accumulation in the environment causes environmental problems, is a major research question. Methods In this work, Dieffenbachia amoena was grown in a growing medium that had substituted peanut shells and Azolla mixes composts (0, 15, 30, 45, 60, and 100 v/v %) for peat. The controls received only peat: perlite (2:1 v/v) without composts. Results It was found that, as the substitution of compost increased, nutrients also increased in the growing medium. Nonetheless, the nutrients led to minor changes in the leaves. As compost increased, the bulk density of the growing media decreased (0.17, 0.16, 0.15, and 0.15 g cm−3). The range of substrate physical properties, such as container capacity, air-filled porosity, and total porosity, was within the recommended range. The 15–100% substitution of compost increased the electrical conductivity and pH of the growing media. The 30% compost treatment led to significant differences in the final height (32.06 cm), trunk diameter (11.66 mm), stem and leaf fresh weight (57.52 g), and stem and leaf dry weight (5.10 g) in comparison with the controls. Conclusions Considering the high price of peat in comparison with compost, replacing peat with 30% compost is economically preferable. Compost was thus found to be a good alternative to peat as an ornamental plants growing medium.

Drought stress is one of the major abiotic stresses that limits rice productivity in the world. In this study 83 diverse rice genotypes were evaluated under reproductive-stage drought stress and non-stress conditions in a completely randomized design with three replications. Eleven well known stress tolerance and susceptibility indices were calculated based on the grain yield under stress and non-stress conditions. Also rank mean (RM) indices were calculated based on the ranks of genotypes for the former calculated indices. The highest seed yield under non-stress condition belonged to the genotypes Sangjo, Zenith, IR70445-146-3-3, Norin 22 and Ghasroldashti. Under stress condition, however, IR83750-131-1, IR74718-24-2-3, Sepidrood, TETEP and IR71739-24-3-5 genotypes showed the highest seed yield. STI, GMP, MRP and REI indices with positive and significant correlations with grain yield in stress and non-stress conditions were found to be the most suitable indices for selection of drought tolerant rice genotypes. According to these indices, IR83750-131-1, Sangjo, Sepidrood, Zenith and IR58 genotypes showed the highest ranks and had a higher tolerance to drought stress. Based on RM index, IR83750-131-1, IR74718-24-2-3, Sepidrod, TETEP and IR74720-13-1-2 obtained the highest ranks. Cluster analysis grouped the most drought tolerant genotypes in the second cluster.

A quantitative trait is a measurable trait that depends on the cumulative action of many genes and their interaction with the environment that can vary among individuals over a given range to produce a continuous distribution of phenotypes. The identification and mapping of QTLs for such traits has great significance for rice breeders. In this study, a genetic analysis of quantitative trait loci (QTLs) affecting 11 agronomical traits was performed using an F2 population of a cross between two Oryza sativa ssp. indica type cultivars, Domsiah and IR44, comprising 160 plants. A total of 22 QTLs were detected for 11 traits, including two for plant height (PH), one for full grain per panicle (FG), two for flag leaf width (FLW), three for 1000-grain weight (TGW), two for number of panicles per plant (NP), three for flag leaf length (FL), two for peduncle length (Pd), one for panicle exertion (PE), two for grain yield (GY), two for basal panicle length (BPL) and two for awn length (AL).

A quantitative trait is a measurable trait that depends on the cumulative action of many genes and their interaction with the environment that can vary among individuals over a given range to produce a continuous distribution of phenotypes. The identification and mapping of QTLs for such traits has great significance for rice breeders. In this study, a genetic analysis of quantitative trait loci (QTLs) affecting 11 agronomical traits was performed using an F2 population of a cross between two Oryza sativa ssp. indica type cultivars, �Domsiah� and �IR44�, comprising 160 plants. A total of 22 QTLs were detected for 11 traits, including two for plant height (PH), one for full grain per panicle (FG), two for flag leaf width (FLW), three for 1000-grain weight (TGW), two for number of panicles per plant (NP), three for flag leaf length (FL), two for peduncle length (Pd), one for panicle exertion (PE), two for grain yield (GY), two for basal panicle length (BPL) and two for awn length (AL).

Six rice cultivars were crossed in half diallel design to evaluate their GCA and SCA in 2005. In the following year, parents and their progenies were grown in a randomized complete block design with three replications, and 10 traits were measured. The analysis of variance showed significant differences (p≤0.01) between cultivars. Furthermore, general combining ability (GCA) and specific combining ability (SCA) for parents and hybrids were significant. Therefore, additive and non-additive gene effects on controlling traits were demonstrated. According to the analysis based on the second and fourth Griffing methods, additive gene effects were more than non-additive gene effects on controlling growth period, plant height, panicle length, number of panicles/plant and brown rice length, while other studied traits were more controlled by non-additive gene effects. Comparison of the second and fourth Griffing methods showed that the proportions of additive and non-additive variances in two methods were different. Moreover, GCA and SCA resulting from the two methods for several traits such as vegetative and productive growth period, plant height, number of filled grains/panicle and grain yield were significant. Therefore, it could be concluded that using parental generations in the second Griffing method may cause biased estimate of the GCA and SCA variances. Thus, using the fourth Griffing method is more suitable than the other methods in providing time, cost and facilities, and is recommended as an applicable method.

Experiments were conducted to study the effects of temperature and chemical treatments on the vase life of cut Asiatic hybrid lily cultivar Pisa, with sixteen chemical treatments using factorial design with 3 replication arrangements. Lilium cut flowers were harvested when the first flower colored fully. Following chemical treatments, they were grouped in different combinations before storage. The treatments included sucrose, 8- hydroxy quinoline sulfate (HQS), citric acid (CA), gibberellic acid (GA3), kinetine (KI) and distilled water as control. Lilium cut flowers were pulsed for 24 hours in different solutions, then brought out and kept in the distilled water at temperatures of 4°C and 22 ° C .Effects of applied treatments were evaluated on different characteristics like vase life, the amount of water absorbed, flower diameter, total soluble solids and fresh weight. Results showed that the temperature of 4°C had the most effect on vase life, keeping the quality of lilium cut flowers. The results also displayed that the chemical treatments kinetine + sucrose had the most effect on vase life and percentage of sucrose, gibberellic acid + kinetine delayed yellowing of the foliage, 8- hydroxy quinoline absorbed the most amount of water, and treatments sucrose + kinetine , gibberellic acid + 8- hydroxy quinoline sulfate and gibberellic acid + citric acid were most effective in increasing the flowers diameter.