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.
morteza gorzin; farshid ghaderi-far; ebrahim zeinali; seyed esmaeil razavi; mohammad monyan ardestani
Abstract
This study was conducted to investigate the effects of planting date, foliar application of benomyl fungicide and potassium silicate in improving the quality of soybean (cv. Williams) seed in Gorgan during 2011 and 2012. In the first year (2011), the experimental treatments were including planting dates ...
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This study was conducted to investigate the effects of planting date, foliar application of benomyl fungicide and potassium silicate in improving the quality of soybean (cv. Williams) seed in Gorgan during 2011 and 2012. In the first year (2011), the experimental treatments were including planting dates (April 20, May 13, June 3, June 29 and July 22) and foliar application of benomyl fungicide (used at R3 + R6 or unused) and in the second year (2012) were including planting dates (May 1 and July 7), foliar application of benomyl fungicide, silicon (Si) and silicon + benomyl. Water-soluble potassium silicate as silicon supply, in three stages (V6, R1 and R4), at the concentration of 40 grams per liter was sprayed on the leaves. The results showed that an increase in air temperature during seed filling period (R5-R7) in the early planting dates is the most important factor in reducing seed quality. Also, a significant negative correlation was observed between seed infection by Phomopsis sp. and Nigrospora sp. and seed germination and vigor. Delayed planting by reducing the temperature during seed filling period and seed infection by this pathogenic fungi, increased seed quality. Foliar application of benomyl fungicide and potassium silicate by reducing seed infection by pathogenic fungi, improved the quality of soybean seeds. Thus, the delay in planting of precocious cv. Williams, foliar application of potassium silicate and benomyl fungicide in reproductive stages can be advised as the strategies to enhance the seed quality of this cultivar to the farmers and seed producers in Gorgan.