ALi N h八 小 A 240 (h) () Figure I Pollen germination of O.alta and growth of hybrid ovaries.(a)Ovaries of Guang-lu-ai4 at 10 d after anthesis:(b)ovaries of Guang-lu-ai4/O.alta at 13-14 DAP:(c)bigger ovaries of Guang-lu-ai4/O.alta at 18-19 DAP:(d)smaller ovaries of Guang-lu-ai4/O.alta at 18-19 DAP:(e)ovaries of Liaojing944/0.alta at 11-13 DAP:(f)ovaries of L202/0.a/ta at 14 DAP:(g)ovaries of L202/0.alta at 20 DAP:(h)pollen germina tion and pollen tube growth of O.alta on the stigma of Guang-lu-ai4(1000x):(i)mature pollen grains of O.alta(100x).Bar=1 cm. Biology of plant reproduction
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(d) (h) ①) () Figure 2 Embryo and endosperm development of hybrid Guang-lu-ai4/O.alta at 1,3 and 7 DAP.(a)1 DAP small globular-shaped embryo (arrow)and normal free endosperm nuclei;(b)1 DAP.small globular-shaped embryo(arrow)and degenerating free endosperm nuclei:(c)1 DAP,fertilization trace (arrow)and fertilized egg cell:(d)3 DAP.normal pear-shaped embryo (arrow)and endosperm cells:(e)3 DAP.embryo developmental stagnation (arrow) and degenerated free endosperm nuclei:(f)3 DAP.egg cell fertilization stagnation.showing fertilization trace(arrow)and unfertilized polar nuclei left (arrow head)in single-fertilized embryo sac:(g)7 DAP.globular-shaped embryo with incompact structure(arrow)and degenerated free endosperm nuclei: (h)7 DAP.embryo differentiating organs(arrow)and cellular endosperms;(i)degenerated egg apparatus and tissues in chaos in unfertilized embryo sac at 1 DAP:(j)female-germ unit degeneration(arrow)and tissues in chaos in unfertilized embryo sac at 3 DAP:(k)7 DAP.degenerated egg apparatus(ar- row)and polar nuclei (arrow head)in unfertilized embryo sac:(1)7 DAP,degenerated female-germ unit (arrow)and nucellus tissues occupation in the distorted锦8ya品 reproduction
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(c) d (D (h) Figure 4 Embryo sac development and mature embryo sac structure of hybrid Guang-lu-ai4/O.alta.(a)Archesporial cell:(b)normal megasporocyte (c)megasporocyte with the nucleus in abnormal position:(d)abnormal degeneration of tetrad and no formation of functional megaspore:(e)functional megaspore degeneration:(f)embryo sac degeneration and nucellus tissue abnormal at embryo sac matured stage:(g)no organ formation in degener- ated embryo sac at embryo sac matured stage:(h)matured embryo sac in abnormal position. Biology of plant reproduction 8
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b 紧学 柠 e (0 (g) Figure5 Pollen fertility(100)and PMC meiosis I(1000)of hybrid Guang-lu-ai4/O.ala (a)one stainable pollen grain (arrow)and typical abortive pollen grains:(b)diakinesis I with 361:(e)diakinesis I with 211+321.arrow showing bivalents:(d)metaphase I with IIV+5II+221.arrow showing quadrivalents:(e)metaphave I with 3III+311+211.arrow showing trivalents:(f)metaphase I with chromosome straggling (arrow):(g)anaphase I with laggards(arrow):(h)anaphase I with precocious migration of univalents(arrow):(1)anaphase I with imbalanced chromovomes in two poles.(ana- phasve I with multivalent bridge (arrow).(k)telophave I with chromatin masses:(1)telophase I with abnormal spindle orientation:(m)a dyad with ab. normal nuclei:(n)abnormal cytokinesis and spindle orientation:(o)a dyad with abnormal nuclei:(p)triad
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(k) (m) (n) (p) Figure 6 PMC meiosis II and early uninucleate microspore of hybrid(1000x).(a)Metaphase II with chromosome straggling(arrow)and abnormal cytokinesis:(b)metaphase II with chromosomes concentrated in one of the sister cells:(c)anaphase II with laggards (arrow):(d)telophase II with abnor- mal meiosis:(e)telophase II with chromosomes concentrated in one of the sister cells:(f)telophase II with spindle orientation in multi-directions:(g) telophase II with abnormal spindle orientation:(h)telophase II with micronuclei (arrow):(i)a tetrad with abnormal nuclei:(i)a tetrad with abnormal nuclei and micronuclei (arrow):(k)a tetrad with abnormal nuclei and sister cells in disorder arrangement:(1)a triad formed at tetrad stage:(m)a triad with a binucleate microspore (arrow):(n)a triad with restitutional nucleus in one microspore (arrow):(o)pentad:(p)an early uninucleate microspore with abnormal nucleus
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