The Difference Of Different Maturity And Germination Of Vicia Cracca To Salt And Alkali Stresses

This article selects the legume forages-Vicia cracca widely distributed in north China as the research object. To mark the flowers when they completely open in 2009²010 (in early August at peak anthesis) and collect the seeds from 21 to 42 days after peak anthesis(DAPA) at three-day intervals, collecting eight maturity of seeds. Choose NaCl and set 6 salt concentration gradients including 0, 50, 100, 150, 200, 250 mmol L^-1, choose Na2CO3 and set 3 alkali concentration gradients including 0, 25, 50 mmol L^-1. Germinate the eight maturity seeds by means of measuring the indoor germination and admeasure six germination indexes including percentage germination, germination energy, germination rate, radical longth, germ longth and vigor index for exploring different maturity seeds have different resistance and salt-alkaline mechanism to stress. The results were as follows:(1) In different salinity-alkalinity stress, percentage germination, germination energy and germination rate descend after the increasing with the maturity. The increasing amplitude is biger when the maturity is from 21 to 30 DAPA, the descending amplitude is small from 33 to 42 DAPA. Less than 100 mmol L^-1 salt concentration, they reduce slowly with the increasing of salt concentration; more than 150 mmol L^-1, every index drop sharply. When the alkali concentration is 25 mmol L^-1, and contrast, each index has slightly lower, they are almost all 0 in 50 mmol L^-1.(2) In different salinity-alkalinity stress, radical longth, germ longth and vigor index descend after the increasing with the maturity. They are biggest in different concentration salinity-alkalinity stress from 30 to 36 DAPA and decrease with the stress increasing. With the increasing of salt concentration, each index gradually decrease and each index has a sharp declining with the increasing of alkali concentration.(3) Salt stress compared with alkali, different maturity seeds in the same concentrations Na+, on salt stress germination index is higher than on alkali in 2009. In 2010, on salt stress percentage germination is higher than on alkali. When the maturity is 30 DAPA before, on alkali stress germination energy is higher than on salt,from 33 to 42 DAPA, on salt stress germination energy is higher than on alkali. When the maturity is 33 DAPA before, on alkali stress germination rate is higher than on salt, from 36 to 42 DAPA, on salt stress germination rate is higher than on alkali. The radical longth, germ longth and vigor index are higher on salt stress than alkali stress.Two years of study results indicate that the germination ability is the strongest when Vicia cracca's seeds have been collected from 30 to 36 DAPA. Low concentrati- ons salinity-alkalinity stress (Salt concentration≤100 mmol L^-1, Alkali concentration≤25 mmol L^-1), percentage germination is the potential 80% above, germination energy is the potential 60% above, germination rate is the potential 50% above. Radical longth, germ longth and vigor index are the biggest when Vicia cracca's seeds have been collected from 30 to 36 DAPA. It is thus clear that when the maturity is from 30 to 36 DAPA the resistance to salt and alkali stress is best. This research result can be used to guide the reproductive and harvest of Vicia cracca's and soil improvement on lightly saline-alkali land.