H T; S M; H Z
Abstract
The present research was conducted to study the effect of irrigation treatments on growth indices, yield, and water use efficiency of long green pepper (Capsicum annuum L.) at the research greenhouse of Shahrekord University. This experiment was done in a clay-loam soil using randomized design with four ...
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The present research was conducted to study the effect of irrigation treatments on growth indices, yield, and water use efficiency of long green pepper (Capsicum annuum L.) at the research greenhouse of Shahrekord University. This experiment was done in a clay-loam soil using randomized design with four treatments i.e. 40%, 60%, 80%, and 100 percent of water requirement and three replications, in 12 pots, during 2012. The obtained results from statistical analysis indicated that the effect of irrigation water on growth indices, yield, and water use efficiency (WUE) was significant at 5% level. Maximum yield and maximum water use efficiency were achieved in treatment of 100 percent water requirement i.e. full irrigation. Furthermore, it was observed that water use reduction by 20%, 40% and 60 percent led to reduction in yield by 26.98%, 50.92% and 69.49 percent, respectively. Moreover, it was observed that water use reduction by 20%, 40% and 60 percent led to reduction in water use efficiency by 10.56%, 22.24% and 29.35% percent, respectively. Since there was no significant difference in yield between 100% and 80 percent treatments, it is recommended that under water shortage conditions, the maximum reduction in water application be limited to 20 percent of water requirement.
Sara Mardaninejad; Hamid zare; Hasan Tabatabaei; Abdorahman Mohammadkhani
Abstract
Water stress and the limitation of plants water requirement have different effects on the underground organs growth indices. In this research, the effects of water stress on the growth of long green pepper root were studied in comparison with the regular method of irrigation in the greenhouse conditions. ...
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Water stress and the limitation of plants water requirement have different effects on the underground organs growth indices. In this research, the effects of water stress on the growth of long green pepper root were studied in comparison with the regular method of irrigation in the greenhouse conditions. Irrigation treatments included 4 levels, viz. 40%, 60%, 80%, and 100 percent of the crop water requirement (CWR). At the end of the growing season, the root sampling was done and some of the root indices such as fresh and dry weight, root surface area and volume, length and root length density, and surface area to fresh weight ratio were measured for each treatment and compared with those of the control (100 percent CWR). Duncan's multiple range test showed that, with increasing irrigation water, the weight, volume, surface and root length increased. Therefore, all the studied indices in the 40 % CWR treatment were the lowest in comparison with the control treatment. Besides, in the 80 % CWR, decrease in fresh and dry weight of root was, respectively, 4.7 % and 31 %; in the 60 %CWR, fresh and dry weight decreased 10.5% and 47.7 %, respectively; and in the 40 % CWR treatment, fresh and dry weight of root decreased 25.7 % and 62.5 %, respectively, in comparison to the control treatment. Also, root surface and volume in the 80 %CWR decreased by 9% and 19.8 percent; in the 60% CWR treatment by 16.1% and33.8%; and in the 40 % CWR treatment by 25.8% and 47.3%, respectively, in comparison to the control treatment. The results showed that the root average growth in the control, 80%, 60%, and 40% CWR treatments reached the depth of 50, 48, 43, and 39 cm at the rate of 0.35, 0.33, 0.3, and 0.27 cm/day, respectively. The results of the three stress treatments showed that the reduction ratio of root traits in the 80% CWR was more appropriate compared with the other treatments. These results show savings in water consumption, which is important in terms of economic. Also, in all of the treatments, the amount of root length density decreased with soil depth penetration. In other word, most of the roots density was observed in the surface layer of soil.