scholarly journals Pollen and Spikelet Analysis in F1 Rice Hybrids and their Parents

2014 ◽  
Vol 8 ◽  
pp. 120-126 ◽  
Author(s):  
Bal K. Joshi ◽  
Laxmi P. Subedi ◽  
Santa B. Gurung ◽  
Ram C. Sharma
Keyword(s):  
Pollen Fertility ◽  
Practical Importance ◽  
Pollen Grains ◽  
Gene Interaction ◽  
Pollen Sterility ◽  
Spikelet Fertility ◽  
High Fertility ◽  
Male Sterile ◽  
Pollen Abortion ◽  
Spikelet Sterility

Pollen analysis can be used to discriminate between different species, identify possible  interspecies hybrids, identify restorer and maintainer lines, useful to study genetics of  restorer gene, interaction between chromosome and cytoplasm and relationship between  parents. Pollen abortion system of male sterility is an important tool in hybrid rice  production and spikelet is the major yield components. Nine improved cultivars, six  landraces and three wild aborted cytoplasmic-genetic male sterile (CMS) lines were used to  analyze pollen and spikelet in F1 rice hybrids and their parents. The frequency of pollen  categories and its relationship to spikelet fertility were investigated. Pollen sterility of the  F1s was determined by staining pollen grains in 1% potassium iodide-iodine (I-KI) solution.  Spikelet fertility was determined by counting the total number of seed set in proportion to  the total number of spikelets. Correlation and regression coefficients for some traits were  computed. In hybrids, pollen fertility ranged from 0.5 to 82% and spikelet fertility from 0 to  87%. Pollen fertility varied from 28 to 97%, while spikelet fertility from 73 to 91% in pollen  parents. The highest and the lowest percentages of pollen fertility were found in Chaite-6  and Chiunde cultivars respectively. Spikelet fertility percentage varied widely among  hybrids and many hybrids had lower spikelet fertility percentage than their parents.  Therefore, it is of practical importance to understand the causes of high spikelet sterility in  hybrids for possible increase in spikelet fertility. Highly significant positive correlation was  found between stained round fertile (SRF) pollen and spikelet fertility. The positive value of  correlation and regression coefficient on SRF and spikelet fertility were found between F1  and mid parent, and F1 and male parent. High fertility of cross may be due to the presence of  a wide compatibility gene or restorer genes in the cultivar. Lower pollen and spikelet  fertility of the crosses was attributed to effect of the genetic background of the tester parent. Nepal Agric. Res. J. Vol. 8, 2007, pp. 120-126 DOI: http://dx.doi.org/10.3126/narj.v8i0.11605  

Cytoplasmic male sterility in Desmodium

1969 ◽  
Vol 20 (2) ◽  
pp. 227 ◽  
Author(s):  
KS McWhirter
Keyword(s):  
Cytoplasmic Male Sterility ◽  
Male Sterility ◽  
Interspecific Hybrid ◽  
Pollen Fertility ◽  
Pollen Sterility ◽  
Hybrid Origin ◽  
F1 Hybrids ◽  
Male Sterile ◽  
Genetic Stocks

A type of male sterility found in two Desmodium plants of probably interspecific hybrid origin was cytoplasmically inherited. The cytoplasmic male-sterile character was incorporated in the tropical legume Desmodium sandwicense by backcrossing. In this genetic background pollen sterility was complete. The male-sterile character was not graft-transmissible, and it produced no detectable pleiotropic effects on growth and development. Desmodium intortum gave restoration of pollen fertility in Fl hybrids with male-sterile lines of D. sandwicense. Restored F1 hybrids produced apparently normal pollen, but tests of functional ability of the pollen disclosed that pollen fertility was less than that of Fl hybrids with normal cytoplasm. Incomplete restoration of fertility was not due to heterozygosity of fertility-restoring genes with gametophytic expression, since fertility-restoring genes were shown to act sporophytically. The results established the occurrence in the legume Desmodium of a system of determination of the male-sterile, fertility-restored phenotypes that is similar to the cytoplasmic male sterility systems described in many other angiosperm plants. A scheme utilizing the genetic stocks produced in this study for commercial production of the interspecific hybrid D. sandwicense x D. intortum as a cultivar is presented.

scholarly journals Evaluation of cultivars and land races of Oryza sativa for restoring and maintaining wild abortive cytoplasm

1970 ◽  
Vol 1 (2) ◽  
pp. 87-91
Author(s):  
Bal K Joshi ◽  
Laxmi P Subedi ◽  
Santa B Gurung ◽  
Ram C Sharma
Keyword(s):  
Growing Season ◽  
Pollen Sterility ◽  
Pedigree Analysis ◽  
Spikelet Fertility ◽  
Male Sterile ◽  
Animal Science ◽  
F1 Hybrid ◽  
Cms Line ◽  
Hybrid Seeds ◽  
Wild Abortive Cytoplasm

Identification of restorers and maintainers from cultivars and landraces through test crossing and their use in further breeding programme are the initial steps in three-line heterosis breeding. Two experiments, one in the greenhouse for F1 hybrid seeds production and another in the field for parental screening, were conducted during the 1999 rice growing season at the Institute of Agriculture and Animal Science (IAAS, TU), Rampur, Nepal. Three cytoplasmic male sterile (CMS) lines, eight improved cultivars and six landraces of rice were studied for their fertility restoring and sterility maintaining abilities. Pollen sterility was studied based on their stainability with potassium iodide iodine (I-KI) solution. On the basis of their interaction with I-KI, pollens were categorized as unstained withered sterile (UWS), unstained spherical sterile (USS), stained round sterile (SRS) and stained round fertile (SRF). For each hybrid, the percentage of spikelet fertility was estimated. The test lines were categorized as restorers, partial restorers, maintainers, and partial maintainers on the basis of pollen sterility and spikelet fertility. The male sterile lines had mostly UWS and USS types of pollen, whereas the restorer lines had more SRS and SRF types. There was no strong evidence for a relationship between pollen fertility and spikelet fertility. Five restorers, three partial restorers, two partial maintainers and four maintainers were identified. These restorers can be used to develop the hybrid seed while maintainers to maintain and/or to develop new CMS lines, because these are locally adapted cultivars. Pedigree analysis revealed that, for some of these test lines, TN-1 and CR94-13 might be the donors of maintainer and restorer gene(s), respectively. Key words: CMS line, maintainer, restorer, rice Himalayan Journal of Sciences 1(2): 87-91, 2003

Impact of high temperature on pollen germination and spikelet sterility in rice: comparison between basmati and non-basmati varieties

2010 ◽  
Vol 61 (5) ◽  
pp. 363 ◽  
Author(s):  
Bidisha Chakrabarti ◽  
P. K. Aggarwal ◽  
S. D. Singh ◽  
S. Nagarajan ◽  
H. Pathak
Keyword(s):  
High Temperature ◽  
Pollen Germination ◽  
Rice Yield ◽  
Pollen Grains ◽  
Pollen Sterility ◽  
Basmati Rice ◽  
Pollen Deposition ◽  
Spikelet Sterility ◽  
Rice Varieties ◽  
Increased Temperature

Increased temperature due to global warming may reduce pollen germination and induce spikelet sterility in rice crops. Anthesis is the most sensitive stage in rice and exposure to high temperature during this period may cause reduction in floral reproduction. Increased temperature will have different effects on different rice varieties. In the present study the effect of high temperature on pollen as well as on spikelet sterility in basmati (aromatic) and non-basmati (non-aromatic) rice varieties was quantified. Rice varieties were grown at 11 different sowing dates, to see the effect of varying temperature on pollen and spikelet sterility. Rise in temperature increased pollen sterility and reduced germination of pollen grains on the stigma. Temperature above 33°C during anthesis gradually increased pollen sterility in all rice cultivars. At 35.5°C, variety Pusa Sugandh 2 (basmati) recorded a pollen sterility of 17% and 26% reduction in pollen germination. The principal cause of sterility was reduced anther dehiscence and less pollen deposition on the stigma at higher temperature. Increased temperature during the grain-filling period also increased spikelet sterility in rice and variety Pusa Sugandh 2 was most affected. Non-basmati rice varieties were less affected by increased temperature than basmati types. The study indicated that increasing temperature could limit rice yield by affecting pollen germination and grain formation. It also suggested that sensitivity of pollen grains to temperature damage could be taken as one of the most important parameters for predicting rice yield in warmer climates.

THE EFFECT OF TEMPERATURE ON POLLEN FERTILITY AND ANTHER DEHISCENCE OF CYTOPLASMIC MALE-STERILE RYE

1979 ◽  
Vol 59 (3) ◽  
pp. 627-633 ◽  
Author(s):  
G. J. SCOLES ◽  
L. E. EVANS
Keyword(s):  
Pollen Fertility ◽  
Pollen Grains ◽  
Effect Of Temperature ◽  
Anther Dehiscence ◽  
Male Sterile ◽  
Cytoplasmic Male Sterile ◽  
Temperature Regimes ◽  
Secale Cereale L ◽  
Restoration Of Fertility

Pollen fertility and anther dehiscence of two cytoplasmic male-sterile lines of spring rye (Secale cereale L.), their maintainers, their restorers and the F1 between each sterile and restorer were investigated at three temperature regimes (15/10, 20/15 and 25/20 °C). In a second experiment, the anther dehiscence of five additional sterile/restorer hybrids was investigated at the same temperatures. Anthers of male-sterile plants did not contain pollen grains and were non-dehiscent at all temperatures. Pollen fertility of maintainer, restorer and sterile/restorer hybrids varied with temperatures. All anthers of maintainer and restorer lines were fully dehiscent, but partially dehiscent and non-dehiscent anthers occurred in the sterile/restorer hybrids. Anthers of florets in the upper and lower portions of spikes of the sterile/restorer hybrids were often partially dehiscent or non-dehiscent. Variation among tillers of a plant with respect to this character was low, but variation among plants of a sterile/restorer hybrid was high, suggesting genetic segregation. The classification of an anther as either dehiscent, partially dehiscent or non-dehiscent was directly related to pollen fertility. Better restoration of fertility was obtained at temperatures of 20/15 or 25/20 °C than at 15/10 °C.

scholarly journals Identification of Potential Maintainer and Restorer Lines Using Testcross Hybrids

2018 ◽  
Vol 6 (8) ◽  
pp. 953
Author(s):  
Mohammad Amir Hossain ◽  
Md. Jamil Hasan ◽  
Mosammat Umma Kulsum ◽  
Md. Mahathir Sarker
Keyword(s):  
Male Sterility ◽  
Pollen Fertility ◽  
Dominant Gene ◽  
Modifier Genes ◽  
Spikelet Fertility ◽  
Nuclear Genes ◽  
Male Sterile ◽  
Fertility Analysis

Five CMS lines were crossed with 49 genotypes as ‘testers’ to get 245 hybrids. The 245 hybrids were subjected to pollen and spikelet fertility analysis. Among the 245 hybrids 21 hybrids were expressed as restorers, 24 as maintainers, and 200 intermediate types. Six tester’s viz., BR6592-4-6-4, BR6839-41-5-1, IR74052-184-3-3, IR72593-B-3-2-2-2, BR7011-37-1-2, and IR72049-B-R-22-3-1-1 were identified as restorers for highest 2 lines out of the five CMS lines, differently. None of them were found to be restorer for all the five CMS lines. BAU581 was found to be maintainer for four lines except for D.ShanA. Purbachi was found to be maintainer for three lines except for D.ShanA and IR73328A out of the five CMS lines. Out of 245 crosses only 45 crosses contributed directly to the identification of maintainer and restorer. Other crosses were more or, less of intermediate types which indicated neither maintainer nor restorer. It is well known that, pollen fertility is controlled by one dominant gene (RfRf). If pollen fertility is governed by only one gene the product would be either restorer or, maintainer where will be no existence of intermediate types. So, there might be modifier genes in different genotypes which interacted with male sterile nuclear genes that resulted in intermediate male sterility in the crosses.

scholarly journals Genetic mapping of pollen fertility restoration QTLs in rye (Secale cereale L.) with CMS Pampa

2021 ◽  
Author(s):  
Agnieszka Niedziela ◽  
Waldemar Brukwiński ◽  
Piotr Tomasz Bednarek
Keyword(s):  
Genetic Map ◽  
Secale Cereale ◽  
Pollen Fertility ◽  
Fertility Restoration ◽  
Pollen Sterility ◽  
Open Reading Frames ◽  
Phenotypic Variance ◽  
Hybrid Seed Production ◽  
Pollen Abortion ◽  
Secale Cereale L

AbstractCytoplasmic male sterility (CMS) is a widely applied plant breeding tool for hybrid seed production. The phenomenon is often caused by chimeric genes with altered open reading frames (ORFs) located in the mitochondrial genomes and expressed as novel genotoxic products that induce pollen abortion. The fertility of CMS plants can be restored by nuclear-encoded genes that inhibit the action of ORFs responsible for pollen sterility. A recombinant inbred line (RIL) mapping population S64/04/01, encompassing 175 individuals, was used for genetic map construction and identification of quantitative trait loci (QTLs) responsible for fertility restoration in rye (Secale cereale L.) with CMS Pampa. The genetic map of all seven rye chromosomes included 15,516 SNP and silicoDArT markers and covered 1070.5 cm. Individual QTLs explaining 60% and 5.5% of the fertility trait’s phenotypic variance were mapped to chromosomes 4R (QRft-4R) and 5R (QRft-5R), respectively. Association mapping identified markers with the highest R2 value of 0.58 (p value = 2.21E-28). Markers showing the highest associations with the trait were also mapped to the 4R chromosome within the QRft-4R region. Based on marker sequence homology, putative genes involved in pollen fertility restoration were suggested. Five silicoDArTs were converted into PCR-based markers for further breeding purposes.

scholarly journals Slowing Development Facilitates Arabidopsis mgt Mutants to Accumulate Enough Magnesium for Pollen Formation and Fertility Restoration

2021 ◽  
Vol 11 ◽  
Author(s):  
Xiao-Feng Xu ◽  
Xue-Xue Qian ◽  
Kai-Qi Wang ◽  
Ya-Hui Yu ◽  
Yu-Yi Guo ◽  
...  
Keyword(s):  
Fertility Restoration ◽  
Pollen Grains ◽  
General Mechanism ◽  
Wild Type ◽  
Pollen Mitosis ◽  
Male Sterile ◽  
Pollen Abortion ◽  
Slow Development ◽  
Magnesium Transporter ◽  
Pollen Formation

Magnesium (Mg) is an abundant and important cation in cells. Plants rely on Mg transporters to take up Mg from the soil, and then Mg is transported to anthers and other organs. Here, we showed that MGT6+/− plants display reduced fertility, while mgt6 plants are fertile. MGT6 is expressed in the anther at the early stages. Pollen mitosis and intine formation are impaired in aborted pollen grains (PGs) of MGT6+/− plants, which is similar to the defective pollen observed in mgt5 and mgt9 mutants. These results suggest that Mg deficiency leads to pollen abortion in MGT6+/− plants. Our data showed that mgt6 organs including buds develop significantly slower and mgt6 stamens accumulate a higher level of Mg, compared with wild-type (WT) and MGT6+/− plants. These results indicate that slower bud development allows mgt6 to accumulate sufficient amounts of Mg in the pollen, explaining why mgt6 is fertile. Furthermore, we found that mgt6 can restore fertility of mgt5, which has been reported to be male sterile due to defects in Mg transport from the tapetum to microspores and that an additional Mg supply can restore its fertility. Interestingly, mgt5 fertility is recovered when grown under short photoperiod conditions, which is a well-known factor regulating plant fertility. Taken together, these results demonstrate that slow development is a general mechanism to restore mgts fertility, which allows other redundant magnesium transporter (MGT) members to transport sufficient Mg for pollen formation.

scholarly journals Cytological abnormalities and pollen abortion in interspecific hybrids of Nicotiana

2019 ◽  
Author(s):  
Jugou Liao ◽  
Zhiyun Chen ◽  
Zihui Pan ◽  
Yongzhi Niu ◽  
Wenlong Suo ◽  
...  
Keyword(s):  
Interspecific Hybrids ◽  
Developmental Stages ◽  
Developmental Process ◽  
Agronomic Traits ◽  
Interspecific Cross ◽  
Pollen Grains ◽  
Pollen Sterility ◽  
Pollen Abortion ◽  
Carbol Fuchsin ◽  
Sterile Pollen

AbstractInterspecific cross breeding introduces superior agronomic traits into cultivated species; however, problematic pollen sterility occurs in the hybrids. Our previous study obtained interspecific hybrids from the cross between a cytoplasmic male sterility line of Nicotiana tabacum and Nicotiana alata, and some of the hybrids were pollen sterile. Here, we conducted an in-depth cellular study to understand the cytological mechanism of pollen abortion in these hybrids (F1-D sterile) compared with pollen development in the fertile hybrids (F1-S sterile) from the same cross. The ultrastructure observation showed that the membrane of microspore in F1-D sterile hybrid was deficient at all represented developmental stages. Chromosome behavior during meiosis was studied by carbol fuchsin staining, which indicated that cytomixis, chromosome leakage and asymmetric callose wall deposition occurred with high frequency in the microsporocyte of F1-D sterile. The results of the ultrastructure and 6-diamidino-2-phenylindole (DAPI) analyses also showed that the cytoplasm and nucleus were unstable and extruded from F1-D sterile microspore during the developmental process, leading to mature pollen grains that were vacuous and collapsed in the aperture region. In addition, delayed tapetum degradation was also detected in the anther of F1-D sterile, and might be associated with irregular sporopollenin deposition in the aperture region of F1-D sterile pollen. Genetic unbalance and cytomembrane deficiency might both be responsible for the instability of the chromosome, nuclear and cytoplasm, and resulted in pollen abortion in F1-D sterile hybrids, and irregular tapetum degradation might also be related with pollen sterility.

Understanding male sterility in Miconia species (Melastomataceae): a morphological approach

2012 ◽  
Vol 60 (6) ◽  
pp. 506 ◽  
Author(s):  
Priscila Andressa Cortez ◽  
Sandra Maria Carmello-Guerreiro ◽  
Simone Pádua Teixeira
Keyword(s):  
Pollen Tube ◽  
Male Sterility ◽  
Developmental Stages ◽  
Rare Event ◽  
Pollen Grains ◽  
Pollen Grain ◽  
Male Sterile ◽  
Pollen Abortion ◽  
Large Numbers ◽  
Morphological Approach

Pollen abortion occurs in virtually all species and often does not prejudice reproductive success. However, large numbers of abnormal pollen grains are characteristic of some groups. Among them is Miconia, in which partial and complete male sterility is often related to apomixis. In this study, we compared the morphology of pollen grains over several developmental stages in Miconia species with different rates of male sterility. Our aim was to improve the knowledge of mechanisms that lead to male sterility in this ecologically important tropical group. Routine techniques for microscopy were used to examine anthers in several developmental stages collected from the apomictic species Miconia albicans and M. stenostachya. Both species are completely male sterile since even the pollen grains with apparently normal cytoplasm were not able to develop a pollen tube. Meiosis is a rare event in M. albicans anthers and happens in an irregular way in M. stenostachya, leading to the pollen abortion. M. albicans has more severe abnormalities than M. stenostachya since even the microspores and pollen grain walls were affected. Moreover, in M. stenostachya, most mitosis occurring during microgametogenesis was also abnormal, leading to the formation of bicellular pollen grains with two similar cells, in addition to the formation of pollen grains of different sizes. Notably, abnormalities in both species did not reach the production of Übisch bodies, suggesting little or no tapetum involvement in male sterility in these two species.

scholarly journals Mutator-Induced Mutations of the rf1 Nuclear Fertility Restorer of T-Cytoplasm Maize Alter the Accumulation of T-urfl3 Mitochondrial Transcripts

Genetics ◽  
1996 ◽  
Vol 143 (3) ◽  
pp. 1383-1394
Author(s):  
Roger P Wise ◽  
Carren L Dill ◽  
Patrick S Schnable
Keyword(s):  
Pollen Fertility ◽  
Fertility Restoration ◽  
Mitochondrial Rna ◽  
Induced Mutations ◽  
Male Sterile ◽  
Fertility Restorer ◽  
Restorer Genes ◽  
Mitochondrial Transcripts ◽  
Ecori Restriction ◽  
Fertility Restorer Genes

Abstract Dominant alleles of the rf1 and rf2 nuclear-encoded fertility restorer genes are necessary for restoration of pollen fertility in T-cytoplasm maize. To further characterize fertility restoration mediated by the Rf1 allele, 123,500 gametes derived from plants carrying the Mutator transposable element family were screened for rf1-mutant alleles (rf1-m) Four heritable rf1-m alleles were recovered from these populations. Three rf1-m alleles were derived from the progenitor allele Rf1-IAl53 and one was derived from Rf1-Ky21. Cosegregation analysis revealed 5.5- and 2.4kb Mu1-hybridizing EcoRI restriction fragments in all of the male-sterile and none of the male-fertile plants in families segregating for rf1-m3207 and rf1-m3310, respectively. Mitochondrial RNA gel blot analyses indicated that all four rf1-m alleles in male-sterile plants cosegregated with the altered steady-state accumulation of 1.6 and O.6-kb T-urf13 transcripts, demonstrating that these transcripts are Rf1 dependent. Plants carrying a leaky mutant, rf1-m7323, revealed variable levels of Rf1-associated, T-urf13 transcripts and the degree of pollen fertility. The ability to obtain rf1-m derivatives from Rf1 indicates that Rf1 alleles produce a functional gene product necessary for the accumulation of specific T-urf13 transcripts in T-cytoplasm maize.

Sign in / Sign up

Export Citation Format

Share Document