Morning Glories: Jumpin' MG seed!, 1 by RON_CONVOLVULACEAE

RON_CONVOLVULACEAE wrote:
AHH!!! The infamous Megacerus eulophus...how I know it well...this is a seed weevil that is relatively common and most often infect the larger perennial seeds of anything in the MG family...both of these weevils are already very widespread...

The larvae eat the embryo and when the beetle finally matures cuts it's way out leaving a telltale hole in the seedcoat with the embryo clearly eaten away...freezing the fully dried seeds can sometimes kill off the larvae,but these critters have adapted to the cold weather and although freezing fully dried seeds will not cause the embryonic cells to swell and rupture...
freezing seeds(especially quasi-tropical species) in refrigerators can often alter enzymes that may adversely affect viability...although the same seeds allowed to experience the natural wet cold of the natural environment will often improve germination by removing germination inhibitors...

Why there is a difference in the behavior of seeds subjected to refrigeration as compared to seeds which are naturally vernalized remains speculative...

Here is a link to some Ipomoea pandurata seeds showing signs of weevil damage
http://www.pacificbulbsociety.org/pbswiki/files/Ipomoea/Ipom...

Arlan the first 2 photos you posted are Ipomoea lacunosa(the humpback shape is typical)...the 3rd photo is of Ipomoea cordatotriloba(notice the 2 winglike tabs visible on the top of the hilium of the seed just below the letter O of the quarter)...


Here is the photo of Megacerus eulophus I have shared

TTY,...

Ron



This message was edited Jun 30, 2008 1:09 PM