To understand the genetic characteristics of a new photoperiod-sensitive genic male sterile line Mian 9S, some reciprocal crosses were made between Mian 9S and six indica rice materials, Yangdao 6, Luhui 602, Shuihui ...To understand the genetic characteristics of a new photoperiod-sensitive genic male sterile line Mian 9S, some reciprocal crosses were made between Mian 9S and six indica rice materials, Yangdao 6, Luhui 602, Shuihui 527, Mianhui 725, Fuhui 838 and Yixiang 1B. Genetic analysis results suggested that the photoperiod-sensitive genic male sterility (PGMS) of Mian 9S was controlled by a single recessive nuclear gene. Thus, the F2 population derived from the cross of Yangdao 6/Mian 9S was used to map the PGMS gene in Mian 9S. By using SSR markers, the PGMS gene of Mian 9S was mapped on one side of the markers, RM6659 and RM1305, on rice chromosome 4, with the genetic distances of 3.0 cM and 3.5 cM, respectively. The gene was a novel PGMS gene and designated tentatively as pms4. In addition, the application of the pms4 gene was discussed.展开更多
The anatomic research on the mutant clone of Pinus tabulaeformis Carr. in the seed orchard in Xingcheng, Liaoning Province was carried out. The female cone of the mutant clone looked like normal, but its ovules degene...The anatomic research on the mutant clone of Pinus tabulaeformis Carr. in the seed orchard in Xingcheng, Liaoning Province was carried out. The female cone of the mutant clone looked like normal, but its ovules degenerated in the early stage. This paper tries to find out the reason and time of ovule abortion. It seems that the ovule abortion is probably caused by female sterility because the microspores of this mutant clone were normal. Through the serial observations on the one-year-old macrosporangiates and the ovules of two-year-old female cones of mutant and normal clone, it is found that the reason of ovule abortion in mutant clone is the failure of the mitosis of free nuclei in the female gametophyte, and the time is about in the early April.展开更多
The author has treated 93 cases of female sterility with acupuncture. ln accordancewith clinical symptoms and signs, the disease was classified into f0ll0wing types: the stagnation of liv-er-Qi, disharmony of Qi and b...The author has treated 93 cases of female sterility with acupuncture. ln accordancewith clinical symptoms and signs, the disease was classified into f0ll0wing types: the stagnation of liv-er-Qi, disharmony of Qi and blood; deficiency 0f kidney-Yang, infertility of the retention of cold inthe uterus; the retention of phlegm-dampness, vascular obstruction of the uterine c0llaterals; andblood stasis, the stagnation of the uterine collaterals. According to the the0ry of Five Elements, theacupoints were selected to treat each type of syndrome. Of thern, 86 cases were effective, 7 cases in-effective. The effective rate was 92. 5 %.展开更多
A photoperiod-sensitive genic male sterile (PGMS) rice was found in 1973 as a spontaneous mutant of Nongken 58, a japonica variety. Pollen fertility of Nongken 58s (N58s) is completely sterile when grown under long-da...A photoperiod-sensitive genic male sterile (PGMS) rice was found in 1973 as a spontaneous mutant of Nongken 58, a japonica variety. Pollen fertility of Nongken 58s (N58s) is completely sterile when grown under long-day conditions, whereas fertile under short-day conditions. This PGMS was found to be controlled by one or two recessive gene(s), of which one gene(pms)was linked to a marker gene(d-1) on chromosome 5. In order to identify a more precise location of the pms, we analyzed the populations of BCFand BCFof N58s//N58s/KL211(v-10, virescent) and N58s//N58s/KL520 (gh-1, gold hull). The marker genes v-10 and gh-1 are located on the flanking region of d-1. The F, plants of two crosses were fertile. The number of fertile and sterile individuals in BCFfit展开更多
To determine the relationship between female sterility of Pinus tabulaeformis Carr. and plant hormones, content changes of several endogenous plant hormones in a female-sterile clone and a normal clone were analyzed d...To determine the relationship between female sterility of Pinus tabulaeformis Carr. and plant hormones, content changes of several endogenous plant hormones in a female-sterile clone and a normal clone were analyzed during the key period of female gametophyte abortion in mutant clones. The change of ABA content showed a similar pattern between normal and mutant clones, but the ABA content of the mutant clone was always much higher than that of the normal clone. In the normal clone, the IAA content decreased significantly at the early stage of the period and reached its minimum during the first ten days of April and stabilized thereafter. The endogenous ZR levels increased sharply at the early stages and reached a maximum in the middle of April, then decreased dramatically. The IAA and ZR contents of the mutant clone did not change perceptively through the entire period. We conclude that the high levels of ABA and the deficit of IAA and ZR may be the reasons of female gametophyte abortion in the female-sterile clones of P. tabulaeformis.展开更多
This study aimed to provide evidence of persistent uropathogenic Escherichia coli(UPEC) in female patients with recurrent urinary tract infection(UTI) after antibiotic therapy. We collected biopsies of the bladder...This study aimed to provide evidence of persistent uropathogenic Escherichia coli(UPEC) in female patients with recurrent urinary tract infection(UTI) after antibiotic therapy. We collected biopsies of the bladder, and clean-catch urine samples from 32 women who had episodes of recurrent UTI and were given antibiotic therapy. Urine samples and biopsies were analyzed by conventional bacteriological techniques. Phylogenetic group and 16 virulence factors(VFs) of UPEC were determined using polymerase chain reaction(PCR). The infection capability of UPEC was confirmed in a mouse model. Immunofluorescence and electron microscopy were used to detect intracellular bacterial communities(IBCs) in the mouse model. The results showed that all urine specimens were detected sterile. E. coli was found in 6 of 32 biopsies(18.75%), and was identified to be UPEC by PCR. Different VFs associated with the formation of IBCs were identified in all six UPEC isolates. Each UPEC isolate was capable of forming IBCs within the bladder epithelial cells of mice. In conclusion, UPEC with distinctive pathological traits and the capability of IBC formation was first found in the bladders of women after antibiotic therapy, suggesting that the IBC pathogenic pathway may occur in humans and it plays an important role in UTI recurrence.展开更多
Objectives To study characteristics of psychosomatic symptoms related to sterilization, to find out risk factors and their roles ascribed to psychosomatic symptoms, and to establish a mathematic model for screening...Objectives To study characteristics of psychosomatic symptoms related to sterilization, to find out risk factors and their roles ascribed to psychosomatic symptoms, and to establish a mathematic model for screening out susceptible women. Methods: This study enrolled 776 women in rural area at three counties of Linxiang, Qiyang, Changsha of Hunan province in China between February 1990 and April 1992. Brief Neurosis Screening Scale (BNSS), Symptom Checklist 90 (SCL-90), sensitivity to pain, suggestibility were used to indicate subjects' psychological status. Logistic regression model and retrograde discriminant analysis were applied to develop a mathematical model. Results: Prevalence of psychosomatic reactions or symptoms was 54.8% before sterilization, 26.6% at three months and 16.4% at one year after operation respectively. Psychosomatic symptoms were verified to be the result of joint effects of multiple risk factors. The following risk factors were associated with postoperative symptoms: anger-hostility (RR=33.71), high suggestibility (RR=4.53), high neuroticism (RR=3.44), sensitivity to pain (RR=2.14) and operative sites (RR=2.05). A mathematical model to estimate the probability of developing psychosomatic symptoms in sterilization was established.Conclusions: More than half of women suffered from psychosomatic reactions before operation, and some of them did not recover after operation. The postoperative psychosomatic symptoms are the joint effect of multiple risk factors.展开更多
A multi center randomized clinical trial was adopted in the present study. 1705 eligible women with identical demographic and gynecological characteristics were divided into two groups: 871 using phenol atabrine pas...A multi center randomized clinical trial was adopted in the present study. 1705 eligible women with identical demographic and gynecological characteristics were divided into two groups: 871 using phenol atabrine paste (PAP) and 834 using phenol mucilage (PM). The five year follow up rates for the two groups were 97.5% and 98.1%, respectively. The multiple decrement life table analysis showed that there was a significant difference in the gross cumulative failure rates between the two groups. The 60th month gross cumulative failure rates for PAP group and PM group were 4.61% and 11.87%, respectively, thus indicating the efficacy of PAP to be significantly higher than that of PM. 97.7% users had cervical smear examinations, but no suspected cancer cells or cancer cells were found. Meanwhile, there was no known diseases related to the chemical reagent. This follow up study indicates that tubal sterilization by chemical instillation is a simple,safe and efficient female method. It suggested that this method would be introduced to a wider use on the basis of modification in the composition of chemical agents, standardized operational procedure, and improved administrative regulation in the use of this technology.展开更多
Photoperiod-sensitive genie male sterile (PSGMS) rice is a very useful germplasm for hybrid rice development. It was first found as a spontaneous mutant in a japonic a cultivar 'Nongken 58' . pms3 on chromosom...Photoperiod-sensitive genie male sterile (PSGMS) rice is a very useful germplasm for hybrid rice development. It was first found as a spontaneous mutant in a japonic a cultivar 'Nongken 58' . pms3 on chromosome 12 was determined to be the locus where the original PSGMS mutation occurred, changing the normal cultivar Nongken 58 to PSGMS Nongken 58S. Large amounts of RAPD and AFLP analyses were also conducted for the fine mapping of the pms3 genomic region, which resulted in 4 molecular markers linked to pms3. Although these markers somewhat increased the marker density of this region, the pms3 locus is still located in a marker-sparse region.展开更多
Yolk proteins are the main source of nutrients during embryonic and early larval development in oviparous animals. Therefore, vitellogenesis is crucial for reproduction. The silkworm, Bombyx mori, is a model lepidopte...Yolk proteins are the main source of nutrients during embryonic and early larval development in oviparous animals. Therefore, vitellogenesis is crucial for reproduction. The silkworm, Bombyx mori, is a model lepidopteran insect in which there are three yolk proteins: vitellin, 30-kDa protein, and egg-specific protein (Esp). In this study, we explored the gene function of Esp through transgenic clustered regularly interspaced palindromic repeats (CRISPR) / CRISPR-associated protein 9 technology-mediated mutations in the silkworm. We found that Esp mutation resulted in female sterility but had no effect on male fertility. Female mutants could lay eggs after mating, but the eggs were smaller and lighter colored than those laid by wild-type females. The most important finding is that the eggs laid by female mutants did not hatch. Furthermore, we observed stable inheritance of female sterility caused by Esp mutation through successive generations. Thus, Esp encodes a yolk protein that is crucial for female reproductive success and is a potential target for pest control.展开更多
Peiai64S, an indica male sterile rice with a male fertility alteration under different environments, is selected from the offspring of indica rice crossed with Nongken58S. Nongken58S, a japonica pho-toperiod sensitive...Peiai64S, an indica male sterile rice with a male fertility alteration under different environments, is selected from the offspring of indica rice crossed with Nongken58S. Nongken58S, a japonica pho-toperiod sensitive genie male sterile rice (PGMS), deriving from a natural mutant plant individual of normal japonica rice variety, Nongken58, is used as a male sterile gene donor of Peiai64S. But Peiai64S is not a typical PGMS rice, the male fertility is sensitive to temperature just as thermo-sensitive genie male sterile rice (TGMS). We have selected typical PGMS plants in F2 population of Peiai64S× Nongken58, whose ratio of fertile plants to sterile plants is nearly 3:1. The sterility inheritance conformed to one pair of gene segregation model. The result indicates the main male sterile gene in Peiai64S is not other than the PGMS gene, and comes from Nongken58S. The genetic background affects effective expression of the PGMS gene. This suggests that we ought to focus on optimizing the genetic background of the PGMS gene in PGMS rice breeding, and select an ideal genetic background as a transgenic background in molecular breeding.展开更多
A female sterile mutant, derived from a spontaneous mutation, was first discovered In rlce (Oryzs satlvs L. sep. Indlca) restorer llne 202R. Wlth normal fiowerlng, the mutant exhlblts an extremely low seed-sattlng r...A female sterile mutant, derived from a spontaneous mutation, was first discovered In rlce (Oryzs satlvs L. sep. Indlca) restorer llne 202R. Wlth normal fiowerlng, the mutant exhlblts an extremely low seed-sattlng rate. When the mutant Is crossed as a pollen donor, the seeds set normally; whereas when It Is used as a pollen recelver, no seeds are obtalned even wlth mlxed pollen gralns of dlfferent varletles sprlnkled over the atlgmas. The fioret of the mutant, conslatlng of slx stamens and one platll, looks the same as that of the wlld type In the malefemale organs, except that less than 10% of the mutant florets have three atlgmas on the ovary. Although the mutant has a low seed-setting rate, Its pollen fertility Is approximately 87.1%, which Is equal to that of the wild type. In addition, more than 90% of the mature embryo sacs of the mutant have complete Inner structures. At every stage after pollination, the sperm, embryo, and endosperm are not found In the mutant embryo sac, whereas the disintegration of the egg cell that does not accomplish fertilization Is visible. Through observetlons with a fluorescence microscope, we have found that the pollen grains germinate normally, whereas the pollen tube abnormally elongates in the style-transmitting tissue. The mutant pollen tubes display various defects In the style, such as slower elongation, conversed elongation, distorted elongation, swollen tips, or branched tips. As a result, the growth of the pollen tubes ceases In the style, and, therefore, the pollen tubes cannot reach the embryo sac and the process of double fertilization Is blocked. Based on these observations, we conclude that this mutant, designated as fs-202R, Is a novel type of female sterile mutation In rice, which causes the arrest of the elongation of the pollen tube.展开更多
Upland cotton (Gossypium hirsutum L.) shows strong heterosis. However, heterosis is not widely utilized owing to the high cost of hybrid seed production. Creation of a photoperiod-sensitive genetic male sterile line...Upland cotton (Gossypium hirsutum L.) shows strong heterosis. However, heterosis is not widely utilized owing to the high cost of hybrid seed production. Creation of a photoperiod-sensitive genetic male sterile line could substantially reduce the cost of hybrid seed production in upland cotton. Such a mutant with virescent marker was found by space mutation in near-earth orbit and its traits had been stable after 4 years of selection in Anyang and Sanya, China. This mutant was fertile with an 11-12.5 h photoperiod when the temperature was higher than 21.5 ℃ and was sterile with a 13-14.5 h photoperiod. Genetic analysis indicated that both traits were controlled by a single recessive gene or two closely linked genes. Also, the cytological observations and transcriptome profiling analysis showed that the degradation of pollen grain cytoplasm should be the primary reason why the mutant line were male sterile under long-day conditions.展开更多
基金the Crop Breeding Program of Sichuan Province (Grant No. 2006YZGG01)Pre-grant from Youth Science & Technology Foundation of Sichuan Province (Grant No. 07ZQ026-126)
文摘To understand the genetic characteristics of a new photoperiod-sensitive genic male sterile line Mian 9S, some reciprocal crosses were made between Mian 9S and six indica rice materials, Yangdao 6, Luhui 602, Shuihui 527, Mianhui 725, Fuhui 838 and Yixiang 1B. Genetic analysis results suggested that the photoperiod-sensitive genic male sterility (PGMS) of Mian 9S was controlled by a single recessive nuclear gene. Thus, the F2 population derived from the cross of Yangdao 6/Mian 9S was used to map the PGMS gene in Mian 9S. By using SSR markers, the PGMS gene of Mian 9S was mapped on one side of the markers, RM6659 and RM1305, on rice chromosome 4, with the genetic distances of 3.0 cM and 3.5 cM, respectively. The gene was a novel PGMS gene and designated tentatively as pms4. In addition, the application of the pms4 gene was discussed.
基金National Natural Science Foundation of China(Grant No.39970602)
文摘The anatomic research on the mutant clone of Pinus tabulaeformis Carr. in the seed orchard in Xingcheng, Liaoning Province was carried out. The female cone of the mutant clone looked like normal, but its ovules degenerated in the early stage. This paper tries to find out the reason and time of ovule abortion. It seems that the ovule abortion is probably caused by female sterility because the microspores of this mutant clone were normal. Through the serial observations on the one-year-old macrosporangiates and the ovules of two-year-old female cones of mutant and normal clone, it is found that the reason of ovule abortion in mutant clone is the failure of the mitosis of free nuclei in the female gametophyte, and the time is about in the early April.
文摘The author has treated 93 cases of female sterility with acupuncture. ln accordancewith clinical symptoms and signs, the disease was classified into f0ll0wing types: the stagnation of liv-er-Qi, disharmony of Qi and blood; deficiency 0f kidney-Yang, infertility of the retention of cold inthe uterus; the retention of phlegm-dampness, vascular obstruction of the uterine c0llaterals; andblood stasis, the stagnation of the uterine collaterals. According to the the0ry of Five Elements, theacupoints were selected to treat each type of syndrome. Of thern, 86 cases were effective, 7 cases in-effective. The effective rate was 92. 5 %.
文摘A photoperiod-sensitive genic male sterile (PGMS) rice was found in 1973 as a spontaneous mutant of Nongken 58, a japonica variety. Pollen fertility of Nongken 58s (N58s) is completely sterile when grown under long-day conditions, whereas fertile under short-day conditions. This PGMS was found to be controlled by one or two recessive gene(s), of which one gene(pms)was linked to a marker gene(d-1) on chromosome 5. In order to identify a more precise location of the pms, we analyzed the populations of BCFand BCFof N58s//N58s/KL211(v-10, virescent) and N58s//N58s/KL520 (gh-1, gold hull). The marker genes v-10 and gh-1 are located on the flanking region of d-1. The F, plants of two crosses were fertile. The number of fertile and sterile individuals in BCFfit
基金Supported by the National Natural Science Foundation of China (Grant No. 30371144) and Postgraduate Foundation of Beijing Forestry University
文摘To determine the relationship between female sterility of Pinus tabulaeformis Carr. and plant hormones, content changes of several endogenous plant hormones in a female-sterile clone and a normal clone were analyzed during the key period of female gametophyte abortion in mutant clones. The change of ABA content showed a similar pattern between normal and mutant clones, but the ABA content of the mutant clone was always much higher than that of the normal clone. In the normal clone, the IAA content decreased significantly at the early stage of the period and reached its minimum during the first ten days of April and stabilized thereafter. The endogenous ZR levels increased sharply at the early stages and reached a maximum in the middle of April, then decreased dramatically. The IAA and ZR contents of the mutant clone did not change perceptively through the entire period. We conclude that the high levels of ABA and the deficit of IAA and ZR may be the reasons of female gametophyte abortion in the female-sterile clones of P. tabulaeformis.
文摘This study aimed to provide evidence of persistent uropathogenic Escherichia coli(UPEC) in female patients with recurrent urinary tract infection(UTI) after antibiotic therapy. We collected biopsies of the bladder, and clean-catch urine samples from 32 women who had episodes of recurrent UTI and were given antibiotic therapy. Urine samples and biopsies were analyzed by conventional bacteriological techniques. Phylogenetic group and 16 virulence factors(VFs) of UPEC were determined using polymerase chain reaction(PCR). The infection capability of UPEC was confirmed in a mouse model. Immunofluorescence and electron microscopy were used to detect intracellular bacterial communities(IBCs) in the mouse model. The results showed that all urine specimens were detected sterile. E. coli was found in 6 of 32 biopsies(18.75%), and was identified to be UPEC by PCR. Different VFs associated with the formation of IBCs were identified in all six UPEC isolates. Each UPEC isolate was capable of forming IBCs within the bladder epithelial cells of mice. In conclusion, UPEC with distinctive pathological traits and the capability of IBC formation was first found in the bladders of women after antibiotic therapy, suggesting that the IBC pathogenic pathway may occur in humans and it plays an important role in UTI recurrence.
文摘Objectives To study characteristics of psychosomatic symptoms related to sterilization, to find out risk factors and their roles ascribed to psychosomatic symptoms, and to establish a mathematic model for screening out susceptible women. Methods: This study enrolled 776 women in rural area at three counties of Linxiang, Qiyang, Changsha of Hunan province in China between February 1990 and April 1992. Brief Neurosis Screening Scale (BNSS), Symptom Checklist 90 (SCL-90), sensitivity to pain, suggestibility were used to indicate subjects' psychological status. Logistic regression model and retrograde discriminant analysis were applied to develop a mathematical model. Results: Prevalence of psychosomatic reactions or symptoms was 54.8% before sterilization, 26.6% at three months and 16.4% at one year after operation respectively. Psychosomatic symptoms were verified to be the result of joint effects of multiple risk factors. The following risk factors were associated with postoperative symptoms: anger-hostility (RR=33.71), high suggestibility (RR=4.53), high neuroticism (RR=3.44), sensitivity to pain (RR=2.14) and operative sites (RR=2.05). A mathematical model to estimate the probability of developing psychosomatic symptoms in sterilization was established.Conclusions: More than half of women suffered from psychosomatic reactions before operation, and some of them did not recover after operation. The postoperative psychosomatic symptoms are the joint effect of multiple risk factors.
文摘A multi center randomized clinical trial was adopted in the present study. 1705 eligible women with identical demographic and gynecological characteristics were divided into two groups: 871 using phenol atabrine paste (PAP) and 834 using phenol mucilage (PM). The five year follow up rates for the two groups were 97.5% and 98.1%, respectively. The multiple decrement life table analysis showed that there was a significant difference in the gross cumulative failure rates between the two groups. The 60th month gross cumulative failure rates for PAP group and PM group were 4.61% and 11.87%, respectively, thus indicating the efficacy of PAP to be significantly higher than that of PM. 97.7% users had cervical smear examinations, but no suspected cancer cells or cancer cells were found. Meanwhile, there was no known diseases related to the chemical reagent. This follow up study indicates that tubal sterilization by chemical instillation is a simple,safe and efficient female method. It suggested that this method would be introduced to a wider use on the basis of modification in the composition of chemical agents, standardized operational procedure, and improved administrative regulation in the use of this technology.
基金Project supported by the National Program of High Technology Development of China and the Rockefeller Foundation.
文摘Photoperiod-sensitive genie male sterile (PSGMS) rice is a very useful germplasm for hybrid rice development. It was first found as a spontaneous mutant in a japonic a cultivar 'Nongken 58' . pms3 on chromosome 12 was determined to be the locus where the original PSGMS mutation occurred, changing the normal cultivar Nongken 58 to PSGMS Nongken 58S. Large amounts of RAPD and AFLP analyses were also conducted for the fine mapping of the pms3 genomic region, which resulted in 4 molecular markers linked to pms3. Although these markers somewhat increased the marker density of this region, the pms3 locus is still located in a marker-sparse region.
基金This work was supported by the National Natural Science Foundation of China(No.31970476 and 31530072)the China Agriculture Research System(No.CARS-18)the Key Technologies R&D Program for Crop Breeding of Zhejiang Province(No.2016C02054).
文摘Yolk proteins are the main source of nutrients during embryonic and early larval development in oviparous animals. Therefore, vitellogenesis is crucial for reproduction. The silkworm, Bombyx mori, is a model lepidopteran insect in which there are three yolk proteins: vitellin, 30-kDa protein, and egg-specific protein (Esp). In this study, we explored the gene function of Esp through transgenic clustered regularly interspaced palindromic repeats (CRISPR) / CRISPR-associated protein 9 technology-mediated mutations in the silkworm. We found that Esp mutation resulted in female sterility but had no effect on male fertility. Female mutants could lay eggs after mating, but the eggs were smaller and lighter colored than those laid by wild-type females. The most important finding is that the eggs laid by female mutants did not hatch. Furthermore, we observed stable inheritance of female sterility caused by Esp mutation through successive generations. Thus, Esp encodes a yolk protein that is crucial for female reproductive success and is a potential target for pest control.
基金supported by the 9th“Five-Year-Plan”key technology projects in the Bio tech field of“863”program.
文摘Peiai64S, an indica male sterile rice with a male fertility alteration under different environments, is selected from the offspring of indica rice crossed with Nongken58S. Nongken58S, a japonica pho-toperiod sensitive genie male sterile rice (PGMS), deriving from a natural mutant plant individual of normal japonica rice variety, Nongken58, is used as a male sterile gene donor of Peiai64S. But Peiai64S is not a typical PGMS rice, the male fertility is sensitive to temperature just as thermo-sensitive genie male sterile rice (TGMS). We have selected typical PGMS plants in F2 population of Peiai64S× Nongken58, whose ratio of fertile plants to sterile plants is nearly 3:1. The sterility inheritance conformed to one pair of gene segregation model. The result indicates the main male sterile gene in Peiai64S is not other than the PGMS gene, and comes from Nongken58S. The genetic background affects effective expression of the PGMS gene. This suggests that we ought to focus on optimizing the genetic background of the PGMS gene in PGMS rice breeding, and select an ideal genetic background as a transgenic background in molecular breeding.
文摘A female sterile mutant, derived from a spontaneous mutation, was first discovered In rlce (Oryzs satlvs L. sep. Indlca) restorer llne 202R. Wlth normal fiowerlng, the mutant exhlblts an extremely low seed-sattlng rate. When the mutant Is crossed as a pollen donor, the seeds set normally; whereas when It Is used as a pollen recelver, no seeds are obtalned even wlth mlxed pollen gralns of dlfferent varletles sprlnkled over the atlgmas. The fioret of the mutant, conslatlng of slx stamens and one platll, looks the same as that of the wlld type In the malefemale organs, except that less than 10% of the mutant florets have three atlgmas on the ovary. Although the mutant has a low seed-setting rate, Its pollen fertility Is approximately 87.1%, which Is equal to that of the wild type. In addition, more than 90% of the mature embryo sacs of the mutant have complete Inner structures. At every stage after pollination, the sperm, embryo, and endosperm are not found In the mutant embryo sac, whereas the disintegration of the egg cell that does not accomplish fertilization Is visible. Through observetlons with a fluorescence microscope, we have found that the pollen grains germinate normally, whereas the pollen tube abnormally elongates in the style-transmitting tissue. The mutant pollen tubes display various defects In the style, such as slower elongation, conversed elongation, distorted elongation, swollen tips, or branched tips. As a result, the growth of the pollen tubes ceases In the style, and, therefore, the pollen tubes cannot reach the embryo sac and the process of double fertilization Is blocked. Based on these observations, we conclude that this mutant, designated as fs-202R, Is a novel type of female sterile mutation In rice, which causes the arrest of the elongation of the pollen tube.
基金supported by the National Hi-Tech R&D Program of China(2011AA10A102)the National Basic Research Program of China(2010CB126006)
文摘Upland cotton (Gossypium hirsutum L.) shows strong heterosis. However, heterosis is not widely utilized owing to the high cost of hybrid seed production. Creation of a photoperiod-sensitive genetic male sterile line could substantially reduce the cost of hybrid seed production in upland cotton. Such a mutant with virescent marker was found by space mutation in near-earth orbit and its traits had been stable after 4 years of selection in Anyang and Sanya, China. This mutant was fertile with an 11-12.5 h photoperiod when the temperature was higher than 21.5 ℃ and was sterile with a 13-14.5 h photoperiod. Genetic analysis indicated that both traits were controlled by a single recessive gene or two closely linked genes. Also, the cytological observations and transcriptome profiling analysis showed that the degradation of pollen grain cytoplasm should be the primary reason why the mutant line were male sterile under long-day conditions.