Showing 3 results for Emergence
B. Torabi, A. Soltani,
Volume 2, Issue 6 (3-2013)
Abstract
This study was conducted to evaluate the response of emergence to temperature in 4 chickpea cultivars (Beauvanij, Arman, Hashem and Jam) using 12 sowing dates (one per month) under Gorgan environmental conditions (northern Iran) in 2001-2002 and 2002-2003. A dent-like function was used to quantify the response of emergence to temperature. Using this function, the cardinal temperatures (base, lower optimum and higher optimum) and biological day requirement for emergence were determined for different percentiles. Ceiling temperature was taken constantly as
39 ˚C. There was no significant difference between cultivars for cardinal temperatures of 50% population and they were estimated as 4.5, 20.2 and 29.0 ˚C, respectively. Base temperature of 3.4 and 3.0 ˚C, lower optimum of 23.8 and 20 ˚C and higher optimum of 30.3 and 30.0 ˚C were estimated for 10 and 90% populations without significant difference between cultivars. Cultivar differences for biological day requirement of emergence were not significant for 10, 50 and 90% populations. Biological day requirement was estimated as 4.4, 6.1 and 7.9 days for 10, 50 and 90% populations, respectively. Chickpea emergence could be predicted for different percentiles using estimated parameters of this study and weather data.
M. A. Aboutalebian, A. Mohagheghi,
Volume 5, Issue 15 (6-2015)
Abstract
To study the effect of seed priming on seedling emergence characteristics of lentil and evaluate its interaction with drought stress at flowering stage, an experiment was carried out as split plot in a randomized complete block design with three replications at research station of Bu-Ali Sina University, Hamedan, Iran. The main factor consisted drought stress with two levels (conventional irrigation and withholding irrigation at flowering stage) and subplots were seed priming treatments in four levels (priming with zinc sulfate solution, urea solution, distilled water and no-primed). The results showed that priming treatments had positive effects on emergence characteristics, yield and yield components of lentil. Seed priming with zinc sulfate and urea solutions reduced time to 50 percent emergence by 20.15% and increased emergence uniformity coefficient by 15.5 %. The number of pods per plant, number of seeds per pod, 100 seeds weight, grain and biological yields of stressed plants were reduced in comparison with the conventional irrigation treatment. In this study, seed priming with zinc sulfate solution and distilled water increased the mean of pods per plant by 19% under drought stress conditions. The mean of pods per plant increased by 47% when using zinc sulfate and urea solutions under conventional irrigation conditions. The highest number of seeds per pod (1.3) was obtained through priming with zinc sulfate and urea solutions. Compared to no-primed treatment under drought stress conditions, priming with urea solution increased the grain yield by 28.6% (grain yield was 1652.22 kg/ha) and under conventional irrigation conditions, priming with zinc sulfate solution increased the grain yield by 29.2% (grain yield was 2848.57 kg/ha).
Proff. Yahya Emam, Miss Maryam Jahani Doghezloo,
Volume 7, Issue 1 (6-2017)
Abstract
Drought is one of the most important factors limiting crops growth and production and use of plant growth regulators to cope with water stress is of interest to many researchers. In order to study the effects of two plant growth regulators, brassinosteroid (BR) and salicylic acid (SA) on germination and growth of two wheat cultivars in water deficit conditions, a greenhouse experiment was designed and carried out at College of Agriculture, Shiraz University, Shiraz, Iran in 2014. The experiment was factorial based on randomized complete block design, with four replications. Treatments composed of two wheat cultivars (Shiraz and Sirvan), two moisture regimes (50 and100% FC) and growth regulators (BR and SA). In this experiment water stress significantly increased greenness Index (50.58%) and significantly reduced relative water content (10.24%), spike dry weight (17.22%), one hundred seed weight (14.14%), shoot dry weight (8.74%) and seed weight per plant (19.21%). However, plant spray with 25 and 50 µg.L-1 BR and 1mM SA could offset some of the adverse effects of water stress. Furthermore seed priming with BR increased the percentage and rate of seed emergence. Sirvan as a tolerant cultivar for all of the measured traits was shown to be superior to Shiraz, as a sensitive cultivar.
