Pollen germination characteristics, pollen–pistil interaction and reproductive behaviour in interspecific crosses among Abelmoschus esculentus Moench and its wild relatives

Durum wheat (Triticum turgidum subsp. durum) is mostly grown in Mediterranean type environments, characterized by unpredictable rainfall amounts and distribution, heat stress, and prevalence of major diseases and pests, all to be exacerbated with climate change. Pre-breeding efforts transgressing adaptive genes from wild relatives need to be strengthened to overcome these abiotic and biotic challenges. In this study, we evaluated the yield stability of 67 lines issued from interspecific crosses of Cham5 and Haurani with Triticum dicoccoides, T. agilopoides, T. urartu, and Aegilops speltoides, grown under 15 contrasting rainfed and irrigated environments in Morocco, and heat-prone conditions in Sudan. Yield stability was assessed using parametric (univariate (e.g., Bi, S2di, Pi etc) and multivariate (ASV, SIPC)) and non-parametric (Si1, Si2, Si3 and Si6) approaches. The combined analysis of variance showed the highly significant effects of genotypes, environments, and genotype-by-environment interaction (GEI). The environments varied in yield (1370–6468 kg/ha), heritability (0.08–0.9), and in their contribution to the GEI. Several lines derived from the four wild parents combined productivity and stability, making them suitable for unpredictable climatic conditions. A significant advantage in yield and stability was observed in Haurani derivatives compared to their recurrent parent. Furthermore, no yield penalty was observed in many of Cham5 derivatives; they had improved yield under unfavorable environments while maintaining the high yield potential from the recurrent parent (e.g., 142,026 and 142,074). It was found that a limited number of backcrosses can produce high yielding/stable germplasm while increasing diversity in a breeding pipeline. Comparing different stability approaches showed that some of them can be used interchangeably; others can be complementary to combine broad adaption with higher yield.

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A study of Avena macrostachya

Canadian Journal of Botany ◽

10.1139/b76-258 ◽

1976 ◽

Vol 54 (21) ◽

pp. 2434-2439 ◽

Cited By ~ 25

Author(s):

B. R. Baum ◽

Tibor Rajhathy

Keyword(s):

Reproductive Isolation ◽

Reproductive Behaviour ◽

Interspecific Crosses ◽

Epicuticular Waxes ◽

Breeding Programs ◽

Cross Fertilization

The morphology, distribution, developmental and reproductive behaviour, cytology, and glumes' epicuticular waxes of Avena macrostachya, a long overlooked species, have been studied and described. In addition, a few interspecific crosses have been attempted but were unsuccessful. Based on unique traits, such as perenniality, cross-fertilization, and quadrivalent-forming autotetraploidy (2n = 4x = 28), it was found to have an isolated position in Avena. It was concluded, however, that at present there is no strong reason to exclude it from the genus. Because of its unique traits, this species may be particularly important in breeding programs when the nature of its reproductive isolation barriers is understood.

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Fertility analyses of interspecific hybrids between Lagerstroemia indica and L. speciosa

Czech Journal of Genetics and Plant Breeding ◽

10.17221/174/2017-cjgpb ◽

2019 ◽

Vol 55 (No. 1) ◽

pp. 28-34

Author(s):

Yi-Qian Ju ◽

Xing Hu ◽

Yao Jiao ◽

Yuan-Jun Ye ◽

Ming Cai ◽

...

Keyword(s):

Pollen Germination ◽

Germination Rate ◽

Embryo Rescue ◽

Pollen Grains ◽

Female Parent ◽

Interspecific Crosses ◽

Apparent Difference ◽

Breeding Programs ◽

Germination Ability ◽

Sterile Hybrids

Interspecific crosses play an important role in gene introgression, plant improvement and speciation. However, poor fertility of F<sub>1</sub> generation was commonly found, which hampered backcrossing and ideal progeny generation. To explore useful materials for further breeding programs, sterile hybrids (DD1, FD1, ZD3) from different cross combinations of Lagerstroemia indica and L. speciosa and the fertile hybrid (ZD6) were selected. The results showed that pollen grains of sterile hybrids had no germination ability while ZD6 showed 25.90% pollen germination rate. The morphology of stigmas and their papilla cells showed no apparent difference. Normal pollen tubes could be detected in ovaries of ZD6 and ZD3 24 h after pollination. However, the enlarged ovaries of ZD3 began to abscise at 72 h after pollination, which suggested that the barriers occurred during post-fertilization phases. As a consequence, ZD6 can be used as either male or female parent for further Lagerstroemia breeding programs, while the sterile hybrids may be used as female parent through embryo rescue culture.

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Evaluation of rice wild relatives as a source of traits for adaptation to iron toxicity and enhanced grain quality

10.1101/771352 ◽

2019 ◽

Author(s):

Birgit Bierschenk ◽

Melle Tilahun Tagele ◽

Basharat Ali ◽

Md Ashrafuzzaman ◽

Lin-Bo Wu ◽

...

Keyword(s):

Chronic Stress ◽

Genotypic Variation ◽

Wild Relatives ◽

Interspecific Crosses ◽

Spikelet Sterility ◽

Rice Varieties ◽

Stress Symptoms ◽

Individual Traits ◽

Fe Toxicity ◽

Symptom Formation

AbstractRice wild relatives (RWR) constitute an extended gene pool that can be tapped for the breeding of novel rice varieties adapted to abiotic stresses such as iron (Fe) toxicity. Therefore, we screened 75 Oryza genotypes including 16 domesticated O. sativas, one O. glaberrima, and 58 RWR representing 21 species, for tolerance to Fe toxicity. Plants were grown in a semi-artificial greenhouse setup, in which they were exposed either to control conditions, an Fe shock during the vegetative growth stage (acute treatment), or to a continuous moderately high Fe level (chronic treatment). In both stress treatments, foliar Fe concentrations were characteristic of Fe toxicity, and plants developed foliar stress symptoms, which were more pronounced in the chronic Fe stress especially toward the end of the growing season. Among the genotypes that produced seeds, only the chronic stress treatment significantly reduced yields due to increases in spikelet sterility. Moreover, a moderate but non-significant increase in grain Fe concentrations, and a significant increase in grain Zn concentrations were seen in chronic stress. Both domesticated rice and RWR exhibited substantial genotypic variation in their responses to Fe toxicity. Although no RWR strikingly outperformed domesticated rice in Fe toxic conditions, some genotypes scored highly in individual traits. Two O. meridionalis accessions were best in avoiding foliar symptom formation in acute Fe stress, while an O. rufipogon accession produced the highest grain yields in both chronic and acute Fe stress. In conclusion, this study provides the basis for using interspecific crosses for adapting rice to Fe toxicity.

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Realizing Value from Central Asian Allium Germplasm Collections

HortScience ◽

10.21273/hortsci.40.2.309 ◽

2005 ◽

Vol 40 (2) ◽

pp. 309-310 ◽

Cited By ~ 4

Author(s):

Philipp W. Simon

Keyword(s):

Central Asia ◽

Genetic Improvement ◽

Raw Materials ◽

Wild Relatives ◽

Interspecific Crosses ◽

Published Data ◽

Center Of Origin ◽

Germplasm Collections ◽

Central Asian ◽

Genetic Source

Central Asia is the center of origin for many Allium species and a rich genetic source of wild relatives of onion and garlic. For this reason germplasm collections of cultivated Alliums have targeted the acquisition of seed and bulb samples from this region, and several plant expeditions from Asia, Europe, and North America have collected Allium germplasm in Central Asia. Central Asian Allium germplasm has been valuable both as raw materials for scientific research leading to published data, and as starting materials for genetic improvement of the crop. Utilizing this germplasm it has been possible to improve garlic so it can be bred like other seed-propagated crops. Several interspecific crosses have been made between onion and other Central Asian wild relatives and these crosses have yielded useful traits for onion improvement. Allium germplasm from this region has also been important in elucidating the systematics and origins of diversity in onion and garlic. By any of these measures, Central Asian Allium collections have been valuable. Challenges and successes in collecting, maintaining, evaluating, and using these collections remain.

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IN VITRO EMBRYO RESCUE OF INTERSPECIFIC CROSSES FOR TRANSFERRING VIRUS RESISTANCE IN OKRA (ABELMOSCHUS ESCULENTUS (L.) MOENCH)

Acta Horticulturae ◽

10.17660/actahortic.2006.725.30 ◽

2006 ◽

pp. 235-240 ◽

Cited By ~ 4

Author(s):

L. Rajamony ◽

M. Chandran ◽

K. Rajmohan

Keyword(s):

Virus Resistance ◽

Embryo Rescue ◽

Abelmoschus Esculentus ◽

Interspecific Crosses

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Development of Interspecific Hybrids between a Cultivated Eggplant Resistant to Bacterial Wilt (Ralstonia solanacearum) and Eggplant Wild Relatives for the Development of Rootstocks

Plants ◽

10.3390/plants9101405 ◽

2020 ◽

Vol 9 (10) ◽

pp. 1405

Author(s):

Mohamed Rakha ◽

Ahmed Namisy ◽

Jaw-Rong Chen ◽

Mohammed E. El-Mahrouk ◽

Elmahdy Metwally ◽

...

Keyword(s):

Bacterial Wilt ◽

Interspecific Hybrid ◽

Interspecific Hybrids ◽

Embryo Rescue ◽

Solanum Melongena ◽

Wild Relatives ◽

Interspecific Crosses ◽

Viable Seeds ◽

Wild Accessions ◽

Moderately Resistant

Bacterial wilt caused by Ralstonia solanacerum is one of the most economically and destructive eggplant diseases in many tropical and subtropical areas of the world. The objectives of this study were to develop interspecific hybrids, as potential rootstocks, between the eggplant (Solanum melongena) bacterial wilt resistant line EG203 and four wild accessions (S. incanum UPV1, S. insanum UPV2, S.anguivi UPV3, and S. sisymbriifolium UPV4), and to evaluate interspecific hybrids along with parents for resistance to bacterial wilt strains Pss97 and Pss2016. EG203 was crossed successfully with wild accessions UPV2 and UPV3 and produced viable seeds that germinated when wild accessions were used as a maternal parent in the crosses. In addition, viable interspecific hybrids between EG203 and UPV1 were obtained in both directions of the hybridization, although embryo rescue had to be used. Hybridity was confirmed in the four developed interspecific hybrid combinations with three SSR markers. EG203 was resistant to both strains Pss97 and Pss2016, while UPV1 and UPV3 were, respectively, resistant and moderately resistant to Pss2016. The four interspecific hybrids with UPV2, UPV3, and UPV1 were susceptible to both bacterial wilt strains, indicating that the resistance of EG203, UPV1, and UPV3 behaves as recessive in interspecific crosses. However, given the vigor of interspecific hybrids between eggplant and the three cultivated wild species, these hybrids may be of interest as rootstocks. However, the development of interspecific hybrid rootstocks resistant to bacterial wilt will probably require the identification of new sources of dominant resistance to this pathogen in the eggplant wild relatives.

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Effect of water content on the germination characteristics of Trichosanthes cucumerina, Momocardia charantia and Abelmoschus esculentus seeds

Journal of Applied Biology & Biotechnology ◽

10.7324/jabb.2016.40502 ◽

2016 ◽

Keyword(s):

Water Content ◽

Abelmoschus Esculentus ◽

Effect Of Water ◽

Germination Characteristics

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BARRIERS TO HYBRIDIZATION OF TRIFOLIUM REPENS WITH RELATED SPECIES

Canadian Journal of Genetics and Cytology ◽

10.1139/g72-047 ◽

1972 ◽

Vol 14 (2) ◽

pp. 381-389 ◽

Cited By ~ 20

Author(s):

Chi-Chang Chen ◽

Pryce B. Gibson

Keyword(s):

Pollen Tube ◽

Trifolium Repens ◽

Related Species ◽

Pollen Tube Growth ◽

Pollen Germination ◽

Pollen Tubes ◽

Tube Growth ◽

Interspecific Crosses ◽

Viable Seeds ◽

Time Required

Pre-fertilization barriers to hybridization of Trifolium repens L. with its related species, T. nigrescens, T. occidentale, T. hybridum, T. ambiguum, and T. uniflorum, were studied by comparing pollen germination, pollen-tube growth, and fertilization following intra- and interspecific pollinations on T. repens. Pollen of T. repens began to germinate almost immediately after being placed on the stigmas of its own species; pollen germination approached 100% in 30 min. Pollen tubes grew rapidly. Eight hours after pollination the longer tubes had entered the micropyle of the most distant ovules. Fertilization was first observed at 8 hr. All ovules were fertilized within 24 hr. In interspecific pollinations using T. repens as the pistillate parent, the time required for pollen germination was longer and the frequency of germination was lower. Pollen tubes frequently swelled, coiled, or even burst in the styles. Pollen tubes of the species more closely related to T. repens appeared to grow faster and more normally. Fertilization occurred in all interspecific crosses. The highest frequency of ovules fertilized generally occurred in the species combinations in which pollen-tube growth was most similar to the control and the lowest frequency, in the combinations in which tube growth deviated the most from the control. These observations suggest that pre-fertilization barriers are not the only causes of cross-incompatibility of T. repens with related species. Post-fertilization barriers, which prevent zygotes from developing into viable seeds, also must exist.

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