scholarly journals EMBRYOLOGY OF INTERSPECIFIC CROSSES IN MELILOTUS

1954 ◽  
Vol 32 (3) ◽  
pp. 447-465 ◽  
Author(s):  
John Edward Ross Greenshields
Keyword(s):  
Germ Plasm ◽  
Female Parent ◽  
Early Embryo ◽  
Endosperm Nucleus ◽  
Interspecific Crosses ◽  
Primary Endosperm Nucleus ◽  
Embryo Abortion ◽  
Advanced Embryo ◽  
Essentially Normal ◽  
The Cross

Twelve species of Melilotus were intercrossed and the embryology of the hybrids was studied. The species involved in this study are M. alba, M. officinalis, M. suaveolens, M. polonica, M. dentata, M. altissima, M. hirsutus, M. taurica, M. messanensis, M. italica, M. sulcat, and M. speciosa. Among partially compatible crosses, M. officinalis × M. alba produces the most advanced embryo. Growth of the embryo proceeds normally until about eight days, and more slowly thereafter until the 12th or 13th day, when growth is completely inhibited and the embryo aborts. The reciprocal M. alba × M. officinalis embryo does not grow as large or differentiate as much before aborting by the 11th day. Other crosses, including M. officinalis × M. suaveolens and M. alba × M. messanensis form a normal proembryo that grows slowly to about the sixth day. The proembryo then loses polarity, organ development becomes abnormal, and the ovule aborts about the 12th day. Aborted embryos are also produced in the cross, M. alba × M. dentata. Reciprocal crosses of M. suaveolens and M. altissima and M. altissima × M. polonica produce essentially normal embryos up to eight days. These crosses may be sources of economically important germ plasm. Crosses of M. altissima × M. alba and M. italica × M. altissima exhibit early embryo abortion. The suspensor becomes necrotic in four or five days and the proembryo floats into the ovule cavity, which contains abundant noncellular endosperm. In the cross M. officinalis × M. altissima, neither the zygote nor the primary endosperm nucleus divides. When M. altissima is used as the female parent, the zygote does not divide but the endosperm proliferates. In the cross, M. italica × M. officinalis, neither the zygote nor the endosperm divides. Embryos of M. italica × M. sulcata grow for four or five days, but the primary endosperm nucleus does not divide. The hybrid seed of M. alba × M. suaveolens weighs less than seed of either parent. Although developing ovules are smaller than those of M. suaveolens × M. alba, the embryo of the former is much larger and more differentiated, and endosperm is more abundant. This relationship between these two compatible species is of particular theoretical interest. Although many of the crosses do not mature viable seed, some embryos develop normally to a point where they would be worthy subjects for culture on nutrient agar.

scholarly journals 062 Genetic Relationships among Corylus Species

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 451F-452 ◽  
Author(s):  
V. Erdogan ◽  
S.A. Mehlenbacher
Keyword(s):  
Genetic Relationships ◽  
Female Parent ◽  
Its Region ◽  
Nuclear Ribosomal Dna ◽  
Interspecific Crosses ◽  
Embryo Abortion ◽  
Interspecific Gene Flow ◽  
Wide Range ◽  
Reciprocal Differences ◽  
Matk Sequence

Interspecific hybridization, pollen-stigma incompatibility, and DNA sequence analysis were used to study the relationships among hazelnut (Corylus) species. Interspecific crosses resulted in a wide range of cluster set from 0% to 65%. Reciprocal differences were common. In general, crosses involving C. avellana and C. heterophylla were more successful when used as pollen parents, but crosses involving C. americana were more successful when it was the female parent. C. cornuta, C. californica and C. sieboldiana intercrossed freely in both directions, as did C.colurna and C.chinensis. The Asian species, C. sieboldiana, C.heteropyhlla, and C. chinensis, were not cross-compatible with each other. Fluorescence microscopy showed that pollen-stigma incompatibility exists within and among wild hazelnut species, in addition to the cultivated European hazelnut C. avellana. Pollen-stigma incompatibility and embryo abortion (blank nuts) appear to be major blocks to interspecific gene flow. In addition, the chloroplast matK gene and the Internal Transcribed Spacer (ITS) region of the nuclear ribosomal DNA (nrDNA) were amplified and sequenced. The matK sequence was highly conserved and thus was not informative. However, the ITS sequence was highly informative and parsimony analysis agreed with morphological similarities. Corylus species were placed into four groups: 1) C. avellana, C. maxima, C. americana and C. heterophylla 2) C. colurna, C.chinensis, and C. jacquemontii 3) C. cornuta, C. californica and C. sieboldiana 4)C. ferox.

Reproductive Efficiency in Reciprocal Crosses of Arachis monticola with A. hypogaea Subspecies1

1998 ◽  
Vol 25 (1) ◽  
pp. 7-12 ◽  
Author(s):  
H. E. Pattee ◽  
H. T. Stalker ◽  
F. G. Giesbrecht
Keyword(s):  
New Mexico ◽  
Ploidy Level ◽  
Interspecific Hybrids ◽  
Female Parent ◽  
Reproductive Development ◽  
Interspecific Crosses ◽  
Reproductive Efficiency ◽  
Embryo Abortion ◽  
Reciprocal Crosses ◽  
Cultivated Peanut

Abstract Wild species of Arachis encompass a large number of species which can provide valuable genetic resources for improving A. hypogaea L., the domesticated peanut. Arachis monticola Krapov. and Rig. is the only species which is both cross compatible with A. hypogaea and at the same ploidy level. An evaluation of reproductive efficiency in crosses between A. hypogaea and A. monticola was conducted to better understand the potential for utilization of this germplasm. This study documents the reproductive efficiency of A. monticola in reciprocal crosses with A. hypogaea subsp. hypogaea var. hypogaea cvs. Florunner and NC 6; A. hypogaea subsp. fastigiata var. vulgaris cv. Argentine; and A. hypogaea subsp. fastigiata var. fastigiata cv. New Mexico Valencia C by using selfs as controls. A significant maternal effect was observed among selfs and hybrids for timing of fertilization. Selfs of Florunner and New Mexico Valencia C initiated fertilization by 1 d after pollination, whereas syngamy did not occur in selfs of NC 6, Argentine or A. monticola until after day 1. Fertilization approached 100% in A. monticola and A. hypogaea genotypes except for New Mexico Valencia C, which only had 70% of the eggs fertilized. Embryo abortion was observed in both selfs and interspecific hybrids, with the highest rates in selfs after the pegs entered the soil; but in hybrids abortion also occurred as the peg elongated. Crosses were generally more successful when A. hypogaea was the female parent, and developing cultivars with A. monticola cytoplasm will be difficult. Sixty to more than 90% of growing ovules aborted in different interspecific crosses. Arachis monticola selfs and hybrids most closely followed the pattern of reproductive development of A. hypogaea cv. Argentine, which lends support to the theory that A. monticola is a weedy derivative of the cultivated peanut.

scholarly journals Aneuploid abortion correlates positively with MAD1 overexpression and miR-125b down-regulation

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Juan Zhao ◽  
Hui Li ◽  
Guangxin Chen ◽  
Lijun Du ◽  
Peiyan Xu ◽  
...  
Keyword(s):  
Chromosome Segregation ◽  
Spindle Assembly Checkpoint ◽  
Mitotic Checkpoint ◽  
Early Embryo ◽  
Vital Role ◽  
Control Group ◽  
Embryo Abortion ◽  
Protein Levels ◽  
Mitotic Checkpoint Complex

Abstract Background Aneuploidy is the most frequent cause of early-embryo abortion. Any defect in chromosome segregation would fail to satisfy the spindle assembly checkpoint (SAC) during mitosis, halting metaphase and causing aneuploidy. The mitotic checkpoint complex (MCC), comprising MAD1, MAD2, Cdc20, BUBR1 and BUB3, plays a vital role in SAC activation. Studies have confirmed that overexpression of MAD2 and BUBR1 can facilitate correct chromosome segregation and embryo stability. Research also proves that miR-125b negatively regulates MAD1 expression by binding to its 3′UTR. However, miR-125b, Mad1 and Bub3 gene expression in aneuploid embryos of spontaneous abortion has not been reported to date. Methods In this study, embryonic villi from miscarried pregnancies were collected and divided into two groups (aneuploidy and euploidy) based on High-throughput ligation-dependent probe amplification (HLPA) and Fluorescence in situ hybridization (FISH) analyses. RNA levels of miR-125b, MAD1 and BUB3 were detected by Quantitative real-time PCR (qRT-PCR); protein levels of MAD1 and BUB3 were analysed by Western blotting. Results statistical analysis (p < 0.05) showed that miR-125b and BUB3 were significantly down-regulated in the aneuploidy group compared to the control group and that MAD1 was significantly up-regulated. Additionally, the MAD1 protein level was significantly higher in aneuploidy abortion villus, but BUB3 protein was only mildly increased. Correlation analysis revealed that expression of MAD1 correlated negatively with miR-125b. Conclusion These results suggest that aneuploid abortion correlates positively with MAD1 overexpression, which might be caused by insufficient levels of miR-125b. Taken together, our findings first confirmed the negative regulatory mode between MAD1 and miR-125b, providing a basis for further mechanism researches in aneuploid abortion.

Early events in the embryo sac after intraspecific and interspecific pollinations in Rhododendron kawakamii and R. retusum

1986 ◽  
Vol 64 (2) ◽  
pp. 282-291 ◽  
Author(s):  
V. Kaul ◽  
J. L. Rouse ◽  
E. G. Williams
Keyword(s):  
Seed Set ◽  
Embryo Sac ◽  
Pollen Tubes ◽  
Interspecific Crosses ◽  
Primary Endosperm Nucleus ◽  
Kalmia Latifolia ◽  
Taxonomic Grouping ◽  
Similarities And Differences ◽  
Normal Fertilization

Early events in the embryo sac of Rhododendron kawakamii and R. retusum have been studied after compatible self-pollinations and eight interspecific crosses, using sectioned ovaries, pistil squashes, and seed-set data. Ovules of Rhododendron kawakamii and R. retusum are anatropous, unitegmic, and tenuinucellate, with a typical eight-nucleate, seven-celled embryo sac. Fertilization normally occurs 4–5 days after pollination. The zygote lays down a callose wall but remains undivided during the first 13–15 days after pollination. The primary endosperm nucleus divides soon after fertilization, and development is cellular ab initio. Crosses of R. kawakamii (♂) with R. santapaui and R. retusum and crosses of R. retusum (♂) with R. kawakamii, R. santapaui, R. ovatum, and R. tashiroi showed apparently normal fertilization in a majority of ovules entered by pollen tubes. In crosses of R. kawakamii (♂) with R. quadrasianum and Kalmia latifolia entry of pollen tubes into ovules was delayed and frequently abnormal. Apart from compatible self-pollinations of R. kawakamii an R. retusum, only the cross of R. kawakamii (♂) with R. santapaui produced healthy seedlings. Of the remaining seven interspecific crosses only three showed significant embryo development in control pistils left to mature in situ. Similarities and differences in the breeding behaviour of R. kawakamii and R. retusum are discussed with reference to their taxonomic grouping within subsection Pseudovireya.

Reproductive incompatibility barriers in crosses between Vaccinium corymbosum and V. elliottii

1985 ◽  
Vol 63 (11) ◽  
pp. 1987-1996 ◽  
Author(s):  
C. E. Munoz ◽  
P. M. Lyrene
Keyword(s):  
United States ◽  
Cell Division ◽  
Pollen Tube ◽  
Resting State ◽  
Southeastern United States ◽  
Female Parent ◽  
Vaccinium Corymbosum ◽  
Highbush Blueberry ◽  
Embryo Abortion ◽  
Reproductive Incompatibility

A study was made of barriers to hybridization between tetraploid V. corymbosum L., the cultivated highbush blueberry, and V. elliottii Chapm., a wild diploid blueberry which may be useful in breeding cultivars adapted to the southeastern United States. Both prefertilization and postfertilization barriers were detected. Prefertilization barriers were mainly observed when V. elliottii was the male parent and were manifested as an arrest of pollen tube growth at the base of the style. In cases where fertilization did take place, regardless of which species was used as the female, a strong postfertilization barrier usually prevented development of hybrid zygotes. Zygotes remained in a resting state after fertilization and usually aborted before dividing. Meanwhile, the endosperm underwent four to six cycles of cell division before it started to degenerate. A causal relationship between embryo abortion and endosperm malfunction was not clearly established. Endosperm malfunction and embryo abortion were delayed when V. corymbosum was the female parent.

scholarly journals Interspecific Hybridization in Hazelnut (Corylus)

2000 ◽  
Vol 125 (4) ◽  
pp. 489-497 ◽  
Author(s):  
Veli Erdogan ◽  
Shawn A. Mehlenbacher
Keyword(s):  
Seed Germination ◽  
Seedling Survival ◽  
Genetic Relationships ◽  
Female Parent ◽  
Interspecific Crosses ◽  
Shrub Species ◽  
Cluster Set ◽  
Reciprocal Differences ◽  
Hybrid Seedling ◽  
Bridge Species

Eight Corylus L. (hazelnut) species were intercrossed in all possible combinations to reveal genetic relationships. Pollinations were made on either individually bagged branches or trees covered entirely with polyethylene using mixtures of pollen of five genotypes to minimize low cluster set due to single incompatible combinations. Percent cluster set, seed germination, and hybrid seedling survival were determined. Hybridity of seedlings was verified by inspection of morphological traits. Based on percent cluster set, seed germination, and hybrid seedling survival along with observed morphological similarities, Corylus species were placed in three groups: 1) the tree hazels C. colurna L. (turkish tree hazel) and C. chinensis Franchet (chinese tree hazel), 2) the bristle-husked shrub species C. cornuta Marshall (beaked hazel), C. californica (A.DC.) Rose (california hazel), and C. sieboldiana Blume (manchurian hazel), and 3) the leafy-husked shrub species C. avellana L. (european hazel), C. americana Marshall (american hazel), C. heterophylla Fischer (siberian hazel), and C. heterophylla Fischer var. sutchuensis Franchet (sichuan hazel). The two tree hazel species crossed with each other readily, as did the three bristle-husked shrub species. The frequency of blanks was low (<20%) for crosses of the tree hazels, and <50% for interspecific crosses within the group of bristle-husked species. The leafy-husked shrub species could be crossed with each other in all directions, although cluster set on C. heterophylla was low. For crosses of species belonging to different groups, set was generally low and the frequency of blanks high. Nevertheless, a few hybrid seedlings were obtained from several combinations. When used as the female parent, C. californica set nuts when crossed with all other species, indicating possible value as a bridge species. Crosses involving C. avellana were more successful when it was the pollen parent. In crosses with C. avellana pollen, cluster set on C. chinensis was better than on C. colurna and the frequency of blanks was much lower, indicating that it might be easier to transfer nonsuckering growth habit from C. chinensis than from C. colurna. Reciprocal differences in the success of crosses was observed. The following crosses were successful C. californica × C. avellana, C. chinensis × C. avellana, C americana × C. heterophylla, C. cornuta × C heterophylla, C. californica × C. colurna, and C. americana × C. sieboldiana, but the reciprocals were not.

Crossability Barriers in Interspecific Hybridization of Ricebean [Vigna umbellata (Thunb.) Ohwi and Ohashi] with Other Vigna Species

2021 ◽  
Author(s):  
Neelam Bhardwaj ◽  
Tanuja Kapoor ◽  
Parveen Sharma
Keyword(s):  
Growth Habit ◽  
Growth Period ◽  
Early Embryo ◽  
Grain Legume ◽  
Cropping Pattern ◽  
Storage Pests ◽  
Embryo Abortion ◽  
Vigna Species ◽  
Vigna Umbellata ◽  
Specific Hybridization

Background: Ricebean [Vigna umbellata (Thunb.) Ohwi and Ohashi] is a multipurpose grain legume of Mid-Himalayan region mainly cultivated for food, fodder, green manure and has emerged as a good alternative to other pulse crops such as blackgram and greengram which do not flourish in this region due to their susceptibility to cold temperature stress. It is well reported that the nutritional value of ricebean is higher as compared to many other legumes of the Vigna family and has some superior qualities greater than greengram, blackgram and cowpea. It is also resistance to drought, diseases and pests specially the storage pests during growth period and possesses high percentage of seed viability. Despite having all the favourable traits, it is not much popular among the farmers due to the late maturity and indeterminate growth habit. Instead, farmers prefer other crops which fit easily into their cropping pattern and are easy to harvest. A little genetic improvement with respect to maturity and growth habit can revive its cultivation and show great results in its production as a valuable crop. Thus, the present investigation was formulated to introgress desired traits from mash and adzukibean into otherwise high yielding ricebean genotypes using inter-specific hybridization. Methods: The present investigation involves the inter-specific hybridization among three Vigna species viz, ricebean (Vigna umbellata), blackgram (Vigna mungo) and adzukibean (Vigna angularis). In the year 2017, six genotypes of ricebean (RBHP-36, RBHP-38, RBHP-43, RBHP-61, RBHP-107 and RBHP-108) were crossed with two genotypes of blackgram (HimMash-1 and Palampur-93) and one genotype of adzukibean (HPU-51) in glasshouse conditions. Result: The study revealed that successful crosses were possible only between ricebean and blackgram. All the Inter-specific crosses showed very low pod set percentage ranging from 0 -4% and F1 germination percentage ranging from 20-42%. Pod set percentage and pods harvested varied with combinations of two parental cultivars of each species for most of the inter-specific hybrids. The successful pod set was observed in 16 out of 36 inter-specific crosses. Highest crossability was observed in blackgram and ricebean crosses. Crossing of adzukibean with ricebean showed poor or no pod set among the entire cross combinations which are attributed to early embryo abortion and degeneration during embryogenesis.

scholarly journals Embryo rescue from interspecific crosses in apple rootstocks

2006 ◽  
Vol 41 (6) ◽  
pp. 969-973 ◽  
Author(s):  
Adriana Cibele de Mesquita Dantas ◽  
José Itamar Boneti ◽  
Rubens Onofre Nodari ◽  
Miguel Pedro Guerra
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Embryo Rescue ◽  
Casein Hydrolysate ◽  
Female Parent ◽  
Interspecific Crosses ◽  
Open Pollination ◽  
Apple Rootstocks ◽  
Hand Pollination

The objetive of this work was to rescue immature embryos of apple rootstocks Malus prunifolia (Marubakaido) and Malus pumila (M9) after 40-60 days of pollination and to put them into MS culture media supplemented with agar (6 g L-1) and casein hydrolysate (500 mg L-1). Embryos originated from interspecific crosses and open pollination showed differences in the in vitro responses, depending on the female parent, the developmental stage of the embryo, and the culture medium composition. Embryos of the M. pumila rootstock, rescued within 40 days after pollination and put in culture medium supplemented with indolacetic acid (IAA), gibberellic acid (GA3), kinetin and maltose, resulted in a normal development of plantlets. However, embryos originating from hand-pollination, cultivated in medium supplemented with 14 µM IAA, 5 µM kinetin and 1.5 µM Ga3 (MS1), mainly those of M. prunifolia x M. pumila, showed a high percentage of rusted embryos (96.2%). Embryos from open pollination of M. prunifolia and M. pumila formed calluses. It was possible to identify the influence of the female parent by the enhanced development of M. pumila shoots derived from open or hand-pollination. The crossing of responsive species and the use of the technique of embryo culture provided a rapid and uniform germination and, consequently, the development of fully normal seedlings.

scholarly journals Mating System in a Native Norway Spruce (Picea abies [L.] KARST.) Stand-Relatedness and Effective Pollen Population Size Show an Association with the Germination Percentage of Single Tree Progenies

Diversity ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 266
Author(s):  
Oliver Caré ◽  
Oliver Gailing ◽  
Markus Müller ◽  
Konstantin V. Krutovsky ◽  
Ludger Leinemann
Keyword(s):  
Gene Flow ◽  
Population Size ◽  
Norway Spruce ◽  
High Elevation ◽  
Germination Percentage ◽  
Early Embryo ◽  
Genetic Composition ◽  
Embryo Abortion ◽  
Family Structures ◽  
Single Tree

Norway spruce differs little in neutral genetic markers among populations and provenances often reported, but in terms of putative adaptive traits and their candidate genes, some clear differences have been observed. This has previously been shown for crown morphotypes. Stands with mostly narrow crown shapes are adapted to high elevation conditions, but these stands are scattered, and the forest area is often occupied by planted stands with predominantly broad crowned morphotypes. This raises questions on whether this differentiation can remain despite gene flow, and on the level of gene flow between natural and planted stands growing in close neighbourhood. The locally adapted stands are a valuable seed source, the progeny of which is expected to have high genetic quality and germination ability. The presented case study is useful for spruce plantation by demonstrating evaluation of these expectations. Immigrant pollen and seeds from planted trees could be maladaptive and may alter the genetic composition of the progeny. This motivated us to study single tree progenies in a locally adapted stand with narrow crowned trees in a partial mast year at nuclear genomic simple sequence repeat (SSR) markers. Spruce is a typical open-pollinated conifer tree species with very low selfing rates, which were also observed in our study (s = 0.3–2.1%) and could be explained by efficient cross-pollination and postzygotic early embryo abortion, common in conifers. The estimated high amount of immigrant pollen found in the pooled seed lot (70.2–91.5%) is likely to influence the genetic composition of the seedlings. Notably, for individual mother trees located in the centre of the stand, up to 50% of the pollen was characterised as local. Seeds from these trees are therefore considered to retain most of the adaptive variance of the stand. Germination percentage varied greatly between half-sib families (3.6–61.9%) and was negatively correlated with relatedness and positively with effective pollen population size of the respective families. As pollen mostly originated from outside the stand and no family structures in the stand itself were found, germination differences can likely be explained by diversity differences in the individual pollen cloud.

scholarly journals AtNSE1 and AtNSE3 are required for embryo pattern formation and maintenance of cell viability during Arabidopsis embryogenesis

2019 ◽  
Vol 70 (21) ◽  
pp. 6229-6244
Author(s):  
Gang Li ◽  
Wenxuan Zou ◽  
Liufang Jian ◽  
Jie Qian ◽  
Jie Zhao
Keyword(s):  
Cell Death ◽  
Cell Viability ◽  
Cell Fate ◽  
Embryo Development ◽  
Higher Plants ◽  
Early Embryo ◽  
Embryo Cell ◽  
Early Embryogenesis ◽  
Embryo Abortion ◽  
Cell Fate Decisions

Abstract Embryogenesis is an essential process during seed development in higher plants. It has previously been shown that mutation of the Arabidopsis non-SMC element genes AtNSE1 or AtNSE3 leads to early embryo abortion, and their proteins can interact with each other directly. However, the crucial regions of these proteins in this interaction and how the proteins are cytologically involved in Arabidopsis embryo development are unknown. In this study, we found that the C-terminal including the Ring-like motif of AtNSE1 can interact with the N-terminal of AtNSE3, and only the Ring-like motif is essential for binding with three α motifs of AtNSE2 (homologous to AtMMS21). Using genetic assays and by analysing molecular markers of cell fate decisions (STM, WOX5, and WOX8) in mutant nse1 and nse3 embryos, we found that AtNSE1 and AtNSE3 work non-redundantly in early embryo development, and that differentiation of the apical meristem and the hypophysis fails in the mutants, which have disrupted auxin transportation and responses. However, the upper cells of the suspensor in the mutants seem to have proper embryo cell identity. Cytological examination showed that cell death occurred from the early embryo stage, and that vacuolar programmed cell death and necrosis in the nse1 and nse3 mutant embryos led to ovule abortion. Thus, AtNSE1 and AtNSE3 are essential for maintaining cell viability and growth during early embryogenesis. Our results improve our understanding of the functions of SMC5/6 complex in early embryogenesis in Arabidopsis.

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