Effects of osmopriming and hydropriming on vigour and germination of China aster(Callistephus chinensis(L.) Nees.) seeds

The aim of this research was to evaluate the effects of osmopriming and different hydropriming treatments on the vigour and germination of China aster （Callistephus chinensis） seeds. Seed vigour and germination tests were conducted at 10, 20 and 30℃ in darkness for untreated, osmoprimed and hydroprimed seeds. The following parameters and categories of seeds and seedlings were evaluated： the mean germination time （MGT）, T10, T50, U75-25, U90-10, the percentage of germinating seeds （Gmax）, germination capacity, percentage of abnormal seedlings and dead seeds. The results showed that osmopriming accelerated seed germination to the largest extent and improved the uniformity of germination at 10 and 30℃. Among the hydropriming treatments the highest speed of germination was observed for seeds hydrated in 500 μL of water per 1 g of seeds for 48 h at 15℃. This treatment accelerated seed germination at 10℃ compared with the control. Osmopriming increased seed germination capacity at 30℃. None of the applied hydropriming treatments improved this parameter.

Amelioration of Salinity Stress in Maize Seed Germination and Seedling Growth Attributes through Seed Priming

Germination of seeds and growth of seedling respond to seed priming as priming can guard the damage of salinity stress. A study conducted in the net house of the Department of Agronomy, BAU, Mymensingh during the period from November 2012 to April 2013 investigated the ameliorative effect of seed priming on seed germination and seedling attributes of maize under various salinity stress conditions. The experiment consisted of five seed priming and four salinity levels (NaCl) and laid out in a Completely Randomized Design (CRD) with three replications. Seed germination and seedling attributes of maize varied due to salinity stress and priming. The highest seed germination (95.7%) was recorded when no stress was imposed under hydropriming (48 hours). The germination of seeds performed even well (92.3%) when treated with hydropriming (48 hours) and NaCl@0.25 dS&#183m-1 which was followed by hydropriming (24 hours) under no salinity imposed and NaCl@0.25 dS&#183m-1 salinity. Hydropriming for 48 hours without salt stress performed the best on number of leaves seedling-1 (8), shoot length (28.2 cm), root length (14.5 cm), fresh weight (100.8 g) and dry weight of seedling (50.3 g). The germination and seedling growth parameters were reduced with the increase in salinity levels irrespective of priming while all seed priming treatments showed ameliorative effects. However, reduction in seed germination and seedling attributes were minimal with hydropriming for 48 hours. The results revealed that priming of maize seeds could be used for amelioration of salinity stress and hydropriming for 48 hours appeared as the best seed priming treatment.

Seed Priming with MgCl_(2),CaCl_(2),and ZnCl_(2) as a Biofortification Based-Approach Induces Changes in Anise Seedlings Emergence

Aromatic and medicinal plant species having small seeds havefield emergence problems due to low nutrient supply.Therefore,Pimpinella anisum seeds were hydro and osmoprimed with 100 mM MgCl_(2),CaCl_(2),and ZnCl_(2),for 2,4,and 8 h each to compare their growth attributes during germination and seedling establishment stages.Nontreated seeds were used as control.Both hydro and osmo primed seeds were dried for 48 h before,they were sown in plastic trays in growth room conditions to see the impact of treatments on seedling emergence and growth.The maximum root length(12.90 cm),fresh weight(256.30 mg plant^(-1)),and mean emergence time(MET)were recorded from 8 h MgCl_(2) primed seeds.Similarly,the maximum(97.50,and 98.00%)emergence percentage was observed using 8 h MgCl_(2) primed seeds and nontreated seeds(control treatment).The evaluation of parameters like chlorophyll contents and electrical conductivity showed the 8 h MgCl_(2) priming as the optimum treatment.The evaluation of parameters like chlorophyll contents and electrical conductivity showed the 8 h MgCl_(2) priming as the optimum treatment.The result suggests MgCl_(2) priming worked synergistically and improved seed-ling growth attributes under greenhouse conditions.The chlorophyll content ranged 25.94–35.69 SPAD unit.The highest chlorophyll content was obtained from the seedlings obtained from 4 h CaCl_(2) treatment,which were statistically similar to the chlorophyll contents of the seedlings obtained after 8 h MgCl_(2) treatment and nontreated seeds(control treatment).All other treatments showed inhibition in the chlorophyll contents and growth attributes of the seedlings.In conclusion,MgCl_(2) osmopriming treatments were significantly promotive and better compared to hydro-priming and osmopriming treatments including control treatment in terms of anise seeds germination and emergence.