Evaluation of pollen viability, seed viability and vigor of two Bt rice lines Y7 and P8 carrying cry1B::cry1Aa fusion genes

Controlled pollination experiments were conducted on Acrotriche serrulata R.Br. (Ericaceae) to determine the mating system for this species. Pollen viability and stigma receptivity were investigated to ensure effective timing and sourcing of material for maximum fertilisation. Stigmas were found to be receptive in mature buds, with receptivity maintained while nectar remained within the corolla tube. Germination testing showed that pollen from within mature buds was viable. The mating system of A. serrulata was found to be predominantly outcrossing, with 49.8% of cross-pollinated flowers developing to fruit, compared with 8.7% of self-pollinated flowers. Seed viability did not differ significantly between fruits produced by cross-pollination and those produced by self-pollination, although this may be attributable to low sample sizes available for self-pollinated fruits. These results in combination with morphological features of the flower suggest that a pollinator is required for this species.

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Insecticide Applications During the Pollination Period Do Not Adversely Affect Seed Yields of Loblolly Pine

Southern Journal of Applied Forestry ◽

10.1093/sjaf/9.4.240 ◽

1985 ◽

Vol 9 (4) ◽

pp. 240-243

Author(s):

Gary L. DeBarr ◽

Fred R. Matthews

Keyword(s):

Loblolly Pine ◽

Pollen Viability ◽

Seed Viability ◽

Pollen Grains ◽

Seed Orchard ◽

Sensitive Period ◽

Loblolly Pines ◽

Seed Yields

Abstract Three insecticides--Guthion® (azinphosmethyl), Pydrin® (fenvalerate), and Ambush® (permethrin)--were applied to catkins and to ovulate strobili of loblolly pines (Pinus taeda) at the time of maximum ovulate receptivity to determine their effects upon pollen viability, ovulate strobili survival, seed set, seed yields, and seed viability. Concentrations recommended for seed orchard use did not significantly reduce the number of pollen grains/ovule, in vitro or in vivo pollen germination, survival of ovulate strobili, number of developed seeds/cone, number of filled seeds/cone, germination of full seed, or cause an increase in abnormal seed germination. Operational applications of these insecticides to control the webbing coneworm (Dioryctria disclusa) should not cause adverse effects during this sensitive period of seed development in loblolly pine seed orchards.

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Pollen fertility and seed viability of putative hybrid swarms of Pinus sylvestris and Pinus mugo in Slovakia

Silvae Genetica ◽

10.2478/sg-2019-0003 ◽

2019 ◽

Vol 68 (1) ◽

pp. 14-21

Author(s):

Andrej Kormutak ◽

Martina Brana ◽

Martin Galgoci ◽

Peter Manka ◽

Denisa Sukenikova ◽

...

Keyword(s):

Pinus Sylvestris ◽

Seed Quality ◽

Pollen Viability ◽

Seed Viability ◽

Germination Percentage ◽

Tube Length ◽

Putative Hybrid ◽

Pure Species ◽

Contact Zones ◽

Hybrid Swarms

Abstract Generally acknowledged reduction of the interspecific hybrid fertility was utilized in evaluation of the putative hybrid swarms of Scots pine (Pinus sylvestris L.) and mountain dwarf pine (P. mugo Turra) viability under field conditions. Pollen viability and seed quality of the trees from the four contact zones of P. sylvestris and P. mugo in Slovakia were compared with the corresponding characteristics of the pure populations of these species from three reference localities. Pollen germination percentage was comparable in contact zones and control populations of the species. Statistically significant differences between the parent and hybrid groups were detected in pollen tube length only. In general, pollen tubes of the pure species populations were longer than those in contact zones. At the cone level, the individuals from contact zones possessed shorter cones than the trees of pure species populations P. mugo and P. sylvestris. This was paralleled by a lower number of seeds per cone in contact zones and higher amount of seeds per cone in the P. mugo population. Striking differences between individuals of the contact zones and reference populations were revealed also in germination potentials of their seeds. Significantly higher proportions of germinating seeds was found in the reference populations of P. mugo and P. sylvestris than in their contact zones. Contrary to seed quality parameters mentioned above, the fractions of filled but non-germinating seeds and amounts of empty seeds were higher in contact zones than in the parental species populations, indicating higher frequency occurrence of abortive embryogenesis in the former. The lower fertility characteristics of the individuals from contact zones indicate their hybrid nature.

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The Effectiveness of the Sexual Reproduction in Selected Clonal and Nonclonal Species of the Genus Ranunculus

Biology ◽

10.3390/biology11010085 ◽

2022 ◽

Vol 11 (1) ◽

pp. 85

Author(s):

Dawid Kocot ◽

Ewa Sitek ◽

Barbara Nowak ◽

Anna Kołton ◽

Alina Stachurska-Swakoń ◽

...

Keyword(s):

Sexual Reproduction ◽

Pollen Viability ◽

Seed Viability ◽

Common Species ◽

Natural Habitats ◽

Seed Formation ◽

Germination Ability ◽

Additional Group ◽

Viable Seeds ◽

Formation Efficiency

Generative processes have been evaluated in six European buttercup species in order to verify the hypothesis that the reproduction efficiency of clonal species is lower than that of nonclonal ones. The study covered common species (Ficaria verna, Ranunculus auricomus, R. bulbosus, R. cassubicus, R. lanuginosus) and the endangered R. illyricus. The following properties have been assessed: pollen viability (staining method), pollen grain germination and the pollen-tube elongation in pistil tissues (fluorescence microscopy), seed formation efficiency, seed viability (tetrazolium test) and germination ability by introducing factors interrupting dormancy (low temperature and gibberellin application). Additionally, the pistil morphology was documented for R. bulbosus, R. illyricus and R. cassubicus using SEM techniques. It was demonstrated that the reproductive efficiency, expressed as the production of viable seeds able to germinate, was significantly higher in the species reproducing sexually (especially in R. lanuginosus) compared to the clonal ones. However, the complexity observed leads to separation of an additional group (cluster) of apomictic species: R. auricomus and R. cassubicus, distinguished by the lowest pollen viability and a low ability of the seeds to germinate. In the vegetatively reproducing R. illyricus, the seed formation efficiency was just 13.2% despite the having highest number of pistils in its flowers. The developed seeds of this species observed in our experiment were viable, but in general effective methods to stimulate their germination have not been proposed yet. Here, the first comparative study concerning the biology of sexual reproduction of R. illyricus is presented in the context of its decreasing distribution in natural habitats.

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