Majid Gholamhoseini; farhad habibzadeh; parisa hemmati
Abstract
In dry regions, root systems play a major role in controlling plant growth and yield, thanks to their importance in water absorption. In order to investigate the effect of irrigation regimes on root and shoot traits of sesame (Sesamum indicum L.) genotypes, a field experiment has been conducted in Karaj, ...
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In dry regions, root systems play a major role in controlling plant growth and yield, thanks to their importance in water absorption. In order to investigate the effect of irrigation regimes on root and shoot traits of sesame (Sesamum indicum L.) genotypes, a field experiment has been conducted in Karaj, at Seed and Plant Improvement Institute, during 2017 and 2018. A factorial experiment has been laid out in a completely-randomized design with four replications. This study deals with five genotypes of sesame in two irrigation regimes, including full and low (drought stress) irrigation treatments in terms of root and shoot-related traits. Results show that there have been significant differences between genotypes and irrigation regimes for root and shoot traits. In all genotypes, root length density is higher in full irrigation treatment as well as the upper soil layer (0 to 30 cm deep), compared to stress treatment. In addition, under drought stress conditions root depth increases (by 30% in average) in all genotypes. In contrast, root dry weight has decreased in Dashtestan 2 (15 %), Darab 1 (16 %), and Naz (22 %), and increased in Oltan (1 %), USA-ns 96 (7 %), and Sodan 94 (10 ) genotypes. On the other hand, the highest amount of shoot dry weight belongs to the USA-ns 96 genotype (39 g), and the lowest to Naz cultivar (22 g). Finally, results show that USA-ns 96 genotype, being superior in terms of root characteristics such as root depth and root length density compared to other genotypes, in addition to having more shoot dry weight, show the least dry weight loss under stress conditions.
payman abbaszadeh dahaji; Dina S. Rezaie; Abdolreza Akhgar; Ali A. Soltani
Abstract
In order to evaluate the effect of bacterial isolates on growth parameters and nutrient uptake in two varieties of maize (such as SC704 & TWC645), two experiments were separately conducted based on a completely randomized design with four replications in greenhouse of University of Vali-e-Asr in ...
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In order to evaluate the effect of bacterial isolates on growth parameters and nutrient uptake in two varieties of maize (such as SC704 & TWC645), two experiments were separately conducted based on a completely randomized design with four replications in greenhouse of University of Vali-e-Asr in 2014. The experimental treatments consist of four isolates of fluorescent Pseudomonads (P7, P15, P24 and P29) and control (without bacteria inoculation). The results showed that the inoculation with isolates P29, P15, P7, P15, P29 and p24 respectively increased shoot dry weight (42.9 %), shoot length (23.7 %), leaf area (43.6 %), chlorophyll content (15.9 %), root dry weight (49.8 %) and root mass in variety of SC704 compared to the control (no inoculation). The application of most of the examined isolates enhanced the uptake of N, P, K, Ca and Mn in variety of SC704 significantly compared to the control. The examined isolates increased the uptake of Fe, Zn, Cu and Mn in root and shoot in variety of TWC645 significantly compared to the control. The highest uptake of Zn was observed in treatment P29 which raised the uptake of Zn in root and shoot 66.2 and 41.8 respectively in variety of TWC645 in comparison with control. All isolates had significant effect on SC704 root zinc uptake and largest increase in shoot Zn uptake was related to isolate P29 with 60.2% increase compared to the control. Overall, our observations revealed that the inoculation of maize with selected isolates had effective role on the growth and uptake of nutrients in maize.