Studies of pollen grain germination, pollen tube growth, micropylar penetration and seed set in intraspecific and intergeneric crosses within three Cruciferae species

Euphytica ◽  
1993 ◽  
Vol 67 (3) ◽  
pp. 185-197 ◽  
Author(s):  
C. L. C. Lelivelt
Keyword(s):  
Pollen Tube ◽  
Pollen Tube Growth ◽  
Seed Set ◽  
Pollen Grain ◽  
Tube Growth ◽  
Intergeneric Crosses ◽  
Pollen Grain Germination

Factors limiting hybridization between Penstemon spectabilis and Penstemon centranthifolius

2001 ◽  
Vol 79 (12) ◽  
pp. 1439-1448 ◽  
Author(s):  
Jeannie Chari ◽  
Paul Wilson
Keyword(s):  
Pollen Tube ◽  
Pollen Tube Growth ◽  
Fruit Set ◽  
Seed Set ◽  
Pollen Grain ◽  
Tube Growth ◽  
Natural Hybridization ◽  
Poor Growth ◽  
Pollen Grain Germination ◽  
Isolating Mechanisms

Speciation involves the formation of reproductive isolating mechanisms such as a difference in pollinators, incompatibility between pollen tubes and stylar tissue, hybrid seed abortion, or poor growth of hybrid seedlings. We studied reproductive isolating mechanisms in naturally sympatric populations of Penstemon spectabilis Thurber and Penstemon centranthifolius (Benth.) Benth. where F1 hybrids occurred at very low frequency. We compared conspecific crosses, backcrosses, and heterospecific crosses in terms of pollen grain germination, pollen tube growth, fruit set, seed set, and offspring performance. We found several postpollination barriers to hybridization. When P. spectabilis was the ovule parent, the lack of natural hybridization was partially explained by the presence of two isolating factors: reduced pollen tube growth and reduced seed set. When P. centranthifolius was the recipient, the barrier to hybridization was nearly 100% effective and occurred primarily at the stages of pollen grain germination and fruit set. The success of backcrossing was generally intermediate between conspecific and heterospecific crossing. For these two species, it is likely that partial pollinator specificity in addition to strong postpollination reproductive isolating mechanisms contribute to maintaining the species boundary.Key words: speciation, hybridization, introgression, Penstemon, reproductive isolating barriers.

Pollen Grain Germination and Pollen Tube Growth in Pistil of Rice

Rice Science ◽  
2008 ◽  
Vol 15 (2) ◽  
pp. 125-130 ◽  
Author(s):  
Shi-qiang Chen ◽  
Wang Zhong ◽  
Man-xi Liu ◽  
Zhao-wei Xie ◽  
Hui-hui Wang
Keyword(s):  
Pollen Tube ◽  
Pollen Tube Growth ◽  
Pollen Grain ◽  
Tube Growth ◽  
Pollen Grain Germination

scholarly journals Pollen tube incompatibility reaction on the stigma in selfpollinated Sinapis alba L.

2014 ◽  
Vol 65 (1-2) ◽  
pp. 101-105 ◽  
Author(s):  
Renata Śnieżko ◽  
Krystyna Winiarczyk
Keyword(s):  
Pollen Tube ◽  
Pollen Tube Growth ◽  
Pollen Grains ◽  
Pollen Tubes ◽  
Sinapis Alba ◽  
Pollen Grain ◽  
Tube Growth ◽  
Sinapis Alba L ◽  
Growth Changes ◽  
Incompatibility Reaction

After selfpollination of <em>Sinapis alba</em> L. pollen tubes growth is inhibited on the stigma. The pollen grains germinate 3-4 hours after pollination. The pollen give rise to one or more pollen tubes. They grow along the papillae. In the place of contact between the papilla and pollen tube the pellicula is digested. Then the direction of pollen tube growth changes completely. Pollen tubes grow back on the exine of their own pollen grain, or turn into the air. The pollen tubes growth was inhibited in 6-8 hours after selfpollination. After crosspollination usually there is no incompatibility reaction.

Sign in / Sign up

Export Citation Format

Share Document