Morteza Gorzin; Farshid Ghaderi-Far; Seyed Esmaeil Razavi
Abstract
In order to investigate effects of different fungicide spraying treatments on soybean seed quality, a split plot experiment was conducted in a randomized complete block design with three replications in research field of Gorgan University of Agricultural Science and Natural Resources in 2016. Two spring ...
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In order to investigate effects of different fungicide spraying treatments on soybean seed quality, a split plot experiment was conducted in a randomized complete block design with three replications in research field of Gorgan University of Agricultural Science and Natural Resources in 2016. Two spring (May 28) and summer (July 10) planting dates performed at main plots and fungicides spraying including benomyl, mancozeb, propiconazole, methyl thiophanate, carbendazim and control in two stages R3 and R6 were done in sub plots. Germination, accelerated aging, electrical conductivity, and seed health tests were used to evaluate the quality of seeds. Two fungi Alternaria sp. and Fusarium sp. spread were observed in seed lots, but lower prevalence for Fusarium sp.. Therefore, seed health was most affected by Alternaria sp.. The percentage of healthy seeds in spring sowing date was 21.48% higher than summer sowing date. All used fungicides (especially propiconazole and methyl thiophanate) significantly increased the health, germination, and vigor of seeds compared to control. The produced seeds in summer planting despite of more fungal infection, had higher seed germination and vigor than seeds of spring crops, because of exposing the seed development stages (R5-R8) to low temperatures. In the fact that, air temperature during seed development stages was more important in determining seed germination and vigor compared to pathogens. Therefore, in order to achieve high seed quality, it is appropriate to use summer planting with the utility of suitable fungicides such as propiconazole and methyl thiophanate at R3 and R6 growth stages.
mojgan sanjari; Alireza Siroosmehr; Baratali Fakheri
Abstract
To study the effect of humic acid and drought stress on some physiological characteristics of roselle (Hibiscus sabdariffa) an experiment was conducted in the research field of Agricultural Education Centre of Jiroft in 2013. Field experiment was carried out as split plot design with three replications. ...
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To study the effect of humic acid and drought stress on some physiological characteristics of roselle (Hibiscus sabdariffa) an experiment was conducted in the research field of Agricultural Education Centre of Jiroft in 2013. Field experiment was carried out as split plot design with three replications. Water deficit stress as main factor with three levels (A1 = Irrigation after 50, A2 = 100 and A3 = 150 mm evaporation from pan class A) and humic acid was sub plots in four methods of application (B1 = non humic acid, B2 = with irrigation, B3 = with irrigation + once spraying, B4 = with irrigation + twice spraying). Humic acid was used with irrigation at 10kg/ha and for spraying at 250ml/100l. Drought stress had significant effect on chlorophyll a, chlorophyll b, carotenoids, relative humidity content and proline of roselle leaves. Interaction effect of humic acid and drought stress was only significant for total chlorophyll and soluble carbohydrate. Drought stress decreased chlorophyll a (48.22 percent), chlorophyll b (32.77 percent), carotenoid content (79.64 percent) and relative humidity (12.59 percent), while increased proline content (12.59 percent). Humic acid increased chlorophyll a, chlorophyll b and carotenoids but reduced proline content (15.04 percent).