也谈白天读paper 和晚上/周末读paper# Biology - 生物学
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seeds saving
What Seeds Can Be Saved? And how?
http://gardening.about.com/od/gardenmaintenance/a/SeedSaving.ht
http://forums.gardenweb.com/forums/load/seedsave/msg01153128858
So, is a good rule of them that self-pollinating species are generally safe,
whereas insect/wind-pollinated species require extra attention?
Generally, that's true. But growing only self-pollinating vegetables really
limits you in what vegetables you can grow. It limits you to only using
heirloom (open-pollinated), self-pollinating vegetables and well-stabilized
older hybrids.
It won't keep some newer hybrid things from reverting even if they are self-
pollinating. In other words, if you grow a newer hybrid variety of tomato or
squash that hasn't been around for years and is well-stabilized the seeds
from that tomato or squash may revert the following year regardless of any
cross-pollination that may or may not have taken place. Follow me?
From Mother Earth News
"The easiest way for the beginning seed grower to avoid [cross pollination
problems] is to concentrate on self-pollinating vegetables - such as lettuce
, okra, beans, peas, and tomatoes - which have flowers designed in ways that
discourage or prohibit fertilization by other plants. (Peas and tomatoes,
for example, have already pollinated themselves by the time the flowers open
!) Still, to restrict your efforts to these plants is to miss out on much of
the fun, challenge and satisfaction of growing your own seeds."
And bagging a couple of blooms and hand pollinating them is really quite
simple to do and takes only a few minutes. There is a FAQ on how to do here
at GW. Had your Dad done that you wouldn't be scarred for life. ;)
Help or make it more confusing?
Dave
Bagging Plants to Prevent Cross-Pollination of Vegetables
http://www.vegetablegardener.com/item/11771/bagging-plants-to-p
Bagging as Mechanical Isolation
Plants that are insect-pollinated such as broccoli, cucumbers, watermelon,
and pumpkins can be protected from cross-pollination by using the bagging
technique. Although many gardeners consider tomatoes and peppers "self-
pollinating" plants (and for the most part, it's true) they can and will
cross-pollinate, as well.
So, bagging is exactly what it sounds like; the female flower is covered
with a bag so that pollinators such as insects can't get to her and do the
pollination dance. In the case of tomatoes and peppers, the flowers are "
complete", so you'd cover any flower. If you're working with a plant such as
the pumpkins we talked about above, you'd hand-pollinate the female flower
using either a paintbrush the flower-to-flower technique.
After the romance is over, the flower should be covered with a paper or
light material bag like muslin or a commercial product called Reemay. Don't
use plastic bags for bagging flower heads because this can cause the flower
to fry in the sun or get slimy. The flowers would then be completely
unsuitable for seed production.
For veggies that self-pollinate, cover the blossoms with a bag as soon as
they appear. The bag should be secured to the stem without hurting the plant
. Try using a cotton ball under the edge of the bag and then tie it off with
thick thread or a twist-tie. You do want the tie to be secure, but be
gentile.
A cotton ball placed in this position will also serve to keep determined
bugs from reaching the flower. When you see fruits forming, you can take the
bag off with no further worries. Remember to tie an identifying string or
ribbon onto the stem after the flower has set fruit before you remove the
bag! This way there'll be no question about which flower you pollinated.
Using physical barrier techniques such as bagging doesn't take much time to
perfect and you'll have pure pollinated seed to save for your home seed bank
and next year's garden.
http://www.eatforfreeproject.org/page11.htmhttp://www.eatforfre
图一
http://www.liseed.org/art.html
图二
图三
以上内容都来自网上啊。都给了link， 有兴趣的同学自己去读。
总结：
1)哪些种子不可以留？
hybrid不可以留，除了某些heirloom。
2)哪些种子可以留？
self-pollinating species可以留种，heirloom可以留。比如 lettuce, okra, beans,
peas, and tomatoes都是self-pollinating species，虽然也会有一定程度的cross-
pollination,但是可以忽略不计。
3)哪些可以通过controlled pollination来留种子？
Insect/wind-pollinated species 虽然不能直接留种子，但是通过controlled
pollination也是可以的。方法很多，说两种比较常见和操作性比较强的。方法：1，对
于雌雄同花的，such as broccoli直接在小虫子来授粉之前把花cover起来就行了（不
要用塑料袋，要用纸的或布的），收种子的时候只收这部分的种子（图一）。2,对于雌
雄异花的，主要是瓜类，such as cucumbers, watermelon,and pumpkins，雌花和雄花
都要盖起来（图二），然后人工授粉（图三）。记得在瓜柄上留个标签，免得不小心摘
掉吃了啊。
不对之处请大牛指正。欢迎讨论。
What Seeds Can Be Saved? And how?
http://gardening.about.com/od/gardenmaintenance/a/SeedSaving.ht
http://forums.gardenweb.com/forums/load/seedsave/msg01153128858
So, is a good rule of them that self-pollinating species are generally safe,
whereas insect/wind-pollinated species require extra attention?
Generally, that's true. But growing only self-pollinating vegetables really
limits you in what vegetables you can grow. It limits you to only using
heirloom (open-pollinated), self-pollinating vegetables and well-stabilized
older hybrids.
It won't keep some newer hybrid things from reverting even if they are self-
pollinating. In other words, if you grow a newer hybrid variety of tomato or
squash that hasn't been around for years and is well-stabilized the seeds
from that tomato or squash may revert the following year regardless of any
cross-pollination that may or may not have taken place. Follow me?
From Mother Earth News
"The easiest way for the beginning seed grower to avoid [cross pollination
problems] is to concentrate on self-pollinating vegetables - such as lettuce
, okra, beans, peas, and tomatoes - which have flowers designed in ways that
discourage or prohibit fertilization by other plants. (Peas and tomatoes,
for example, have already pollinated themselves by the time the flowers open
!) Still, to restrict your efforts to these plants is to miss out on much of
the fun, challenge and satisfaction of growing your own seeds."
And bagging a couple of blooms and hand pollinating them is really quite
simple to do and takes only a few minutes. There is a FAQ on how to do here
at GW. Had your Dad done that you wouldn't be scarred for life. ;)
Help or make it more confusing?
Dave
Bagging Plants to Prevent Cross-Pollination of Vegetables
http://www.vegetablegardener.com/item/11771/bagging-plants-to-p
Bagging as Mechanical Isolation
Plants that are insect-pollinated such as broccoli, cucumbers, watermelon,
and pumpkins can be protected from cross-pollination by using the bagging
technique. Although many gardeners consider tomatoes and peppers "self-
pollinating" plants (and for the most part, it's true) they can and will
cross-pollinate, as well.
So, bagging is exactly what it sounds like; the female flower is covered
with a bag so that pollinators such as insects can't get to her and do the
pollination dance. In the case of tomatoes and peppers, the flowers are "
complete", so you'd cover any flower. If you're working with a plant such as
the pumpkins we talked about above, you'd hand-pollinate the female flower
using either a paintbrush the flower-to-flower technique.
After the romance is over, the flower should be covered with a paper or
light material bag like muslin or a commercial product called Reemay. Don't
use plastic bags for bagging flower heads because this can cause the flower
to fry in the sun or get slimy. The flowers would then be completely
unsuitable for seed production.
For veggies that self-pollinate, cover the blossoms with a bag as soon as
they appear. The bag should be secured to the stem without hurting the plant
. Try using a cotton ball under the edge of the bag and then tie it off with
thick thread or a twist-tie. You do want the tie to be secure, but be
gentile.
A cotton ball placed in this position will also serve to keep determined
bugs from reaching the flower. When you see fruits forming, you can take the
bag off with no further worries. Remember to tie an identifying string or
ribbon onto the stem after the flower has set fruit before you remove the
bag! This way there'll be no question about which flower you pollinated.
Using physical barrier techniques such as bagging doesn't take much time to
perfect and you'll have pure pollinated seed to save for your home seed bank
and next year's garden.
http://www.eatforfreeproject.org/page11.htmhttp://www.eatforfre
图一
http://www.liseed.org/art.html
图二
图三
以上内容都来自网上啊。都给了link， 有兴趣的同学自己去读。
总结：
1)哪些种子不可以留？
hybrid不可以留，除了某些heirloom。
2)哪些种子可以留？
self-pollinating species可以留种，heirloom可以留。比如 lettuce, okra, beans,
peas, and tomatoes都是self-pollinating species，虽然也会有一定程度的cross-
pollination,但是可以忽略不计。
3)哪些可以通过controlled pollination来留种子？
Insect/wind-pollinated species 虽然不能直接留种子，但是通过controlled
pollination也是可以的。方法很多，说两种比较常见和操作性比较强的。方法：1，对
于雌雄同花的，such as broccoli直接在小虫子来授粉之前把花cover起来就行了（不
要用塑料袋，要用纸的或布的），收种子的时候只收这部分的种子（图一）。2,对于雌
雄异花的，主要是瓜类，such as cucumbers, watermelon,and pumpkins，雌花和雄花
都要盖起来（图二），然后人工授粉（图三）。记得在瓜柄上留个标签，免得不小心摘
掉吃了啊。
不对之处请大牛指正。欢迎讨论。
