Fig. 1. Ligueless-a, lga (left) and normal type (right)
Fig. 2. Stripe-5, st-5, showing white stripes
Fig. 3. Dwarf mutant, d-59(t), and control.
II. Lists of gene symbols
I. Registration of new gene symbols
In accordance with rule 7, the following gene symbols were registered after an examination for priority and validity, with the assistance of coordinators for respective traits.
Information on the new genes is presented as follows:
Gene Symbol Registration No. 12
Registrant: Masahiko Maekawa (Fac. Agr. Hokkaido University)
Gene symbol: lga
Gene name: liguleless-a
Character expression: Ligule is very short, auricle is underdeveloped or very short, and leaf collar is narrow (Fig. 1).
Name of original line: MA-85152
Gene locus: Linkage group II
Origin: EMS-induced mutation from Akihikari by Dr. H. Fujimaki
Remark: Data on F\2\ segregation and linkage data are reported. Short ligule character resembles the feature due to aul (auricleless, non-allelic to lg) and allelism test is in preparation.
Reference: Maekawa, 1988 (Pub. list 6; RGN, this issue)
Gene Symbol Registration No. 13
Registrant: Masahiko Maekawa (Fac. Agr. Hokkaido University)
Gene symbol: st-5
Gene name: stripe-5
Character expression: Fine stripes are expressed in leaf blade and sheath through growing period, and these stripes are also expressed in glumes (Fig. 2).
Name of original line: H-61-s
Origin: Spontaneous mutation from H-61, (Hokudai linkage tester).
Gene locus: Linkage group II
Remark: Deta on F\2\ segregation and linkage data are reported.
Reference: Maekawa, 1988 (Pub. list 7; RGN, this issue)
Gene Symbol Registration No. 14
Registrant: M.A. Awan and A.A. Cheema (Nuclear Institute, Agriculture and Biology, Faisalabad, Pakistan)
Gene symbol: d-59(t)
Gene name: dwarf (DM107-4)
Character expression: 40% shorter in height as compared to parent cultivar, lodging resistant (Fig. 3).
Name of original line: Basmati 370
Remark: Deta on F\2\ segregation and allelism test show the non-allelic relationship of the dwarf gene in DM107-4 with that in DGWG.
Reference: Awan and Cheema, 1988 (Pub. list 1)
Gene Symbol Registration Nos. 15 and 16
Registrant: G.S. Khush and A. Cruz (International Rice Research Institute)
Gene symbol: chl-8
Gene name: chlorina-8
Name of original line: RGS 250
Origin: Mutant from Dr. R.N. Misra of Central Rice Res. Inst., Cuttack India
Gene locus: Linkage group sug
Gene symbol: chl-9
Gene name: chlorina-9
Name of original line: RGS 347
Origin: Mutant from Dr. R.N. Misra of Contral Rice Res. Inst., Cuttack, India
Gene locus: Linkage group sug
Remark (comnon to Nos. 15 and 16): Data on allelism tests with chl-1, chl-6 and trisomic analysis are reported.
Reference: Khush and Cruz, 1988 (Pub. list 5; RGN, this issue)
Gene Symbol Registration No. 17
Registrant: K.S. Wu, J.C. Glaszmann and G.S. Khush (International Rice Research Institute)
Gene symbol: Amp-4
Gene name: Aminopeptidase-4
Character expression: Monomers. The allozymes do not have the same concentration or the same activity and heterozygous Amp-4 individuals display two bands with the faster one being more intense.
Name of original line: Ma Hae
Gene locus: Linkage group sug
Remark: Data on allelism tests and trisomic analysis are reported.
Reference: Wu et al., 1988 (Pub. list 13)
Gene Symbol Registration No. 18
Registrant: Tsugufumi Ogawa, Lou Lin, R.E. Tabien and G.S. Khush (International Rice Research Institute)
Gene symbol: xa-13
Gene name: Xanthomonas campestris pv. oryzae resistance-13
Character expression: Resistance to Philippine race 6, as a reccessive character, but susceptibility to Philippine races 1,2,3,4 and 5.
Name of original line: BJ 1
Gene locus: Linage group VI+IX
Reference: Ogawa et al., 1987 (Pub. list 8)
Gene Symbol Registration No. 19
Registrant: Satoru Taura, Tsugufumi Ogawa, R.E. Tabien (International Rice Research Institute), Atsushi Yoshimura and Takeshi Omura (Fac. Agr., Kyushu University)
Gene symbol: Xa-14
Gene name: Xanthomonas campestris pv. oryzae resistance-14
Character expression: Resistance to Philippine race 5 as a dominant character, but susceptibility to Philippine races 1,2,3,4 and 6.
Name of original line: Taichung native 1
Gene locus: Linkage group II
Reference: Taura et al., 1987 (Pub. list 12)
Fig. 1. Ligueless-a, lga (left) and normal type (right)
Fig. 2. Stripe-5, st-5, showing white stripes
Fig. 3. Dwarf mutant, d-59(t), and control.
II. Lists of gene symbols
Gene symbols newly adopted (Table 1) and linkage relations newly confirmed (Table 2) are listed. These are supplementary to those listed in RGN 1,2,3 and 4. Linkage groups are numbered as proposed by Kinoshita (RGN 4, p. 10, Table 4).
In this context, a reexamination of gene symbols is proposed as suggested by
coordinators. The list of gene symbols presented in RGN 1 will have to be
reviewed. On that occasion, revisions of gene symbols and nomenclature of the
traits concerned will be discussed with respect to certain genes, and new
guidelines for designating polymeric and other genes will be proposed. We
welcome advice and comments on this subject.
With the development of biochemical and molecular techniques, RFLP maps of rice chromosomes and a physical map of chloroplast DNA are presented in this issue of RGN as research notes. Guidelines for nomenclature of biochemical markers need to be proposed so as to avoid confusion.
Table 1. New gene symbols (Supplement)
========================================================================== Amp-4 Aminopeptidase-4 Bph-6 Brown planthopper resistance-6 bph-7 brown planthopper resistance-7 chl-8 chlorina-8 chl-9 chlorina-9 d-59(t) dwarf (DM107-4) lga liguleless-a Pox-5 Peroxidase-5 sd-6(t) semidwarf-6 Se-3(t) Photosensitivity-3 st-5 stripe-5 xa-13 Xanthomonas campestris pv. oryzae-13 Xa-14 Xanthomonas campestris pv. orzae-14 =========================================================================
=============================================================================== Gene Name Gene locus Reference =============================================================================== Group I (wx group) aph apiculus hairs linked to EST-2 and Pgi-2 11 Pox-5 Peroxidase-5 tripro 3, 39%-Pgi-2 13 Cat-1 Catalase-1 trisomic B, 22%-Pox-5 3,13 Group II (Pl group) st-5 stripe-5 28 7 Group III (A group) Est-5 Esterase-5 triplo 1 13 Got-1 Aspartate amino-transpherase-1 triplo 1 13 Icd-1 Isocitrate dehydrogenase-1 triplo-1 13 Group VI+IX (d-1 group) xa-13 Xanthomonas campestris pv. oryzae resistance-13 link to xa-5 8 Group VIII (la group) Pgd-1 Phosphogluconate dehydrogenase-1 triplo 11,19%-Adh-1 13 Group X (bl-1 group) Amp-1 aminopeptidase-1 triplo 2 13 d-33 group Pox-2 Peroxidase-2 triplo 6,13%-Sdh-1 3 Acp-1 Acid phosphotase-1 triplo 6,28%-Pox-2 3 Acp-2 Acid phosphotase-2 close to Acp-1 13 sug group chlo-8 chlorina-8 triplo 8 5 chlo-9 chlorina-9 triplo 8 5 Amp-4 Aminopeptidase-4 triplo 8 13 ===============================================================================
1. Awan, M.A. and A.A. Cheema, 1988. Personal communication.
2. Hu, C.H. 1987. A newly induced semidwarfing gene with agronomic potentiality. RGN 4: 72-74.
3. Ishikawa, R., T. Kinoshita and H. Morishima, 1987. Trisomic analysis of genes for isozymes: Location of Cat-1, Acp-1 and Pox-2 on chromosomes. RGN 4: 75-76.
4. Kabir, Md. A. and G.S. Khush, 1988. Genetic analysis of resistance to brown planthopper in rice (Oryza sativa L.). Plant Breeding 100: 54-58.
5. Khush, G.S. and A. Cruz, 1988. New chlorina markers for chromosome 8. RGN 5.
6. Maekawa, M. 1988. A new leaf stripe gene st-5, its linkage with d-2 and the location of gene P in the second linkage group. RGN 5.
7. Maekawa, M. 1988. A new allele at the lg locus expressing short ligules. RGN 5.
8. Ogawa, T., L. Lin, R.E. Tabien and G.S. Khush, 1987. A new recessive gene for resistance to bacterial blight of rice. RGN 4: 98-100.
9. Poonyarit, M., D.J. Mackill and B.S. vergara, 1987. Two genes affecting photoperiod sensitivity in rice. RGN 4: 87-89.
10. Rezaul Karim, A.N.M. and M.D. Pathak, 1982. A new genes for resistance to green leafhopper, Nephotetti virescens (Distant) in rice, Oryza sativa L. Crop Prot. 1: 473-490.
11. Sato, Y., R. Ishikawa and H. Morishima, 1987. Linkage analysis of gene Aph for apiculus hair length. RNG 4: 74-75.
12. Taura, S., T. Ogawa, R.E. Tabien, G.S. Khush, A. Yoshimura and T. Omura 1987. The specific reaction of Taichung Native 1 to Philippine race of bacterial blight and inheritance to race (PX0112). RGN 4: 101-102.
13. Wu, K.S., J.C. Glaszmann and G.S. Khush, 1988. Chromosomal locations of ten isozyme loci in rice (Oryza sativa L.) through trisomic analysis. Biochemical Genetics 26: 303-320.
III. Reports from coordinators
1. Current status of analysis and symbols for male-sterile cytoplasms and fertility-restoring genes S.S. Virmani-1, and C. Shinjyo-2
1)International Rice Research Institute, PO Box 933, Manila Philippines
2)Faculty of Agriculture, University of Ryukyus, Nishihara-machi, Okinawa, 903- 01 Japan
Cytoplasmic-genic male sterility has become a focal point of research in rice
genetics since the breeding and extension of hybrid rice in China. In addition
to this, a number of cases of genic male sterility have been reported as either
spontaneous or induced recessive mutations, indicating that microsporogenesis
is controlled by many genes. As to those genes, however, mutual allelism and
linkage relation with other genes remain totally unknown. Therefore, this
report is confined to cytoplasmic-genic male sterility.
Many cases of cytoplasmic-genic male sterility have been reported as are listed up in this report. There are a number of different male-sterile cytoplasms and fertility-restoring genes which interact in different manners. How to identify those cytoplasms and genes will have to be considered in the first place.
a) A model for identification of cytoplasms and restoring genes
Whether two cytoplasms are identical or different can be tested by whether they require the same or different restoring genes. But the interactions between cytoplasms and restorers are complex. A genetic experiment with five cytoplasmic male-sterile (cms) lines and their respective restorer (R) lines, Shinjyo has conducted, will be presented as an example. For this experiment, it is necessary to establish cms and their respective R lines having an isogenic genetic background by recurrent backcrossing. In the experiment, (cms-bo) rf- 1/rf-1 and (cms-bo) Rf-1/Rf-1 which had the cytoplasm and restoring gene derived from Chinsurah boro II in the genetic background of Taichung 65, were used as the standard for comparison. Their F\1\ plants were 50% pollen fertile, indicating the gametophytic action of Rf-1. These and other four sets of cms and R lines to be identified were intercrossed with the results as given in Table 1 (Shinjyo 1984, partly unpublished).
Table 1. Pollen fertilities observed in F\1\ plants from crosses between five
sets of cms and R lines
=============================================================================
Female parent Male parent
=================================================
(cms-bo) (cms-B) (cms-C) (cms-D) (cms-E)
Rf-1/Rf-1 Rf-b/Rf-b Rf-c/Rf-c Rf-d/Rf-d Rf-e/Rf-e
(cms-bo)rf-1/rf-1 50 0 50 50 0
(cms-B)rf-b/rf-b 50 50 50 50 0
(cms-C) rf-c/rf-c 0 0 50 0 0
(cms-D)rf-d/rf-d 0 0 100 100 0
(cms-E)rf-e/rf-e 50 50 50 50 50
=============================================================================
(cms-B)=UR 89; (cms-C)=UR 102; (cms-D)=UR 106; (cms-E)=UR 23, all being
isogenic lines of Taichung 65 maintained by Shinjyo, whose cytoplasms and Rf
genes have been derived form several Indian strains of O. rufipogon,
respectively. Genes Rf-b, Rf-c and Rf-e are gametophytic (giving 50% F\1\
pollen-fertility) while Rf-d is sporophytic (100%) when combined with their
respective cytoplasms.
=============================================================================
Whether the five restoring genes are at the same locus or different loci can be determined as follows: First, the F\1\ plants from (cms-B)Rf-b/Rf/b x (cms- bo)Rf-1/Rf-1 were fully pollen-fertile (100%), as Rf-1 and Rf-b were similarly effective for (cms-B). When the F\1\ plant having (cms-B) Rf-1/Rf-b was pollinated by the maintainer having no restoring genes (Taichung 65; rf-1 and/or rf-b), the progeny plants all had a 50% pollen fertility. When the F\1\ from the reciprocal cross, (cms-bo) Rf-1/Rf-b, was pollinated by the maintainer, the progeny segregated into 50% and 0% types in a 1:1 ratio as Rf-b was not effective for (cms-bo). These results indicate that Rf-1 and Rf-b are at the same locus. Similarly, Rf-c and Rf-d were found to be allelic to Rf-1. In then follows that the four restoring genes, Rf-1, Rf-b, Rf-c and Rf-d, are all allelic although they differ in the mode of interaction with respective cytoplasms. These alleles may be symboled Rf-1 (or Rf-1a), Rf-1b, Rf-1c and Rf-1d, respectively. Their recessive allele carried by Taichung 65 may be symboled rf-1.
Second, when two given restoring genes are independent, the progeny of the F\1\ x maintainer cross will segregate into 75%, 50% and 0% types in a 1:2:1 ratio. This was observed between (cms-E) Rf-e/Rf-e and (cms-bo) Rf-1Rf-1. Their F\1\ plant having (cms-E) Rf-1/Rf-e was 75% pollen-fertile, and when pollinated by the maintainer, the progeny segregated in the manner as expected. However, if the F\1\ plant from the reciprocal cross, (cms-bo) Rf-1/Rf-e, which would be 50% fertile was pollinated by the maintainer, the progeny would segregate into 50% and 0% types in a 1:1 ratio. If this cross only is made, the allelism test cannot be conclusive. There is an evidence suggesting that Rf-e has the same locus as of Rf-2, which was found in a Japanese variety Fukuyama as a restorer for cytoplasm (cms-ld) from an Indica variety of Burma (Lead rice) introduced into Fujisaka 5 (Watanabe et al. 1968; Watanabe 1971; Shinjyo and Watanabe 1977). Rf-e may be symboled Rf-2b.
The restoring genes for cytoplasm (cms-WA) derived from "wild abortive", a wild sterile plant found in Hainan Island, China, are at least two, which appear to interact in different manners according to cross-parents and environmental conditions (Virmani et al. 1986). The effect of some sporophytic restoring genes seems to fluctuate resulting in a wide variability of pollen fertility in much the same manner as is found with sporophytic hybrid-sterility genes (Oka 1988, p. 197). For identifying relevant genes, it will be necessary to establish isogenic lines having those genes. Even with isogenic lines, pollen fertility may fluctuate if restoration is imcomplete.
b) Cytoplasms causing male sterility so far reported
The sources of cytoplasms which have been used to develop cms lines are listed in Table 2. Seven of them are given in RGN 1 (p. 41-42). These cms lines are designated in principle according to the source of the cytoplasm. In some of them, however, different symbols have been used for the same object by different authors. For example, Shinjyo designated the cytoplasm of Chinsurah boro II as (cms-boro) or (cms-bo), but the Chinese workers using the same material designated it as BT. On the other hand some cytoplasms have not been given any symbol, e.g., that of Taichung Native 1 identified at IRRI. It may be symboled (cms-TN).
In addition to those listed in Table 2, a case was reported by Carnahan et al. (1972) in which the cytoplasm was derived from three strains of O. glaberrima into Japonica cultivars of California. However, no positive evidence was produced showing that the observed pollen sterility was cytoplasmic. Probably, it could be the sterility of hybrid usually found between O. glaberrima and O. sativa.
We do not know yet how the cms lines as listed in Table 2 can be classified and identified, as their interrelations largely remain unknown except for the relation between (cms-bo) and (cms-ld) (Shinjyo et al. 1974; Shinjyo and Watanabe 1977). We know that cytoplasms from different sources are not necessarily different. Therefore, the symbols designating cytoplasms from different sources, as given in Table 2, must be taken as tentative. Nevertheless, for the convenience of arrangement, we propose to adopt an interim system of designation, that is, "cms" suffixed by 2-3 alphabet letters representing the donor, e.g., cms-bo (Chinsurah boro II), cms-ld (Lead rice), cms-WA (wild abortive), etc. The symbol for cytoplasm may be enclosed in brackets. We hope the rice geneticists and breeders who have identified a new source of cyto-sterility to adopt the interim designation system as proposed above and to report it to the authors of this note.
c) Restoring genes
Fertility-restoring genes so far reported and their symbols used by respective authors are listed in Table 3. Rf-1 for (cms-bo) is known to belong to the fgl linkage group (Shinjyo 1969, 1975). A number of alleles differing in the reaction to certain cytoplasms have been found at this locus, as mentioned. Rf- 2 for (cms-ld) is independent of Rf-1, and may belong to linkage group VI+IX according to the data from trisomic analysis (Shinjyo, unpublished). It is known that Rf-1 is effective for both (cms-bo) and (cms-ld), but Rf-2 is effective for (cms-ld) only (Shinjyo et al. 1974).
As a number of papers have been published using these symbols, we propose to retain them without change. We propose, however, to designate newly identified restoring genes by "Rf" suffixed by 2-3 letters indicating the cytoplasm source for which the genes have been found to be effective. For example, the two restoring genes suggested for (cms-WA) may be symboled Rf-WA-1(t) and Rf-WA- 2(t), where (t) means tentative. Needless to say, these symbols do not imply that the genes are effective only for the designated cytoplasm. There can be found a web of interrelations when an elaborate analysis is made in the future.
In addition, there are so-called weak restorers (Shinjyo 1975, 1984). Some of them seem to work as complementary genes (Maekawa 1982; Table 3). Their identification is left for investigation in the future.
We are indebted to Dr. H.I. Oka for his critical reading of the manuscript.
Table 2. Male-sterile cytoplasms, their sources and designation
===============================================================================
Cytoplasm donor
================
Species Strain Nuclear donor Reference Interim
designation
proposed
==============================================================================
Sources reported in RGN 1
O. sativa Chinsurah boro II Taichung 65 Shinjyo & Omura 1966 cms-bo
O. sativa Lead rice Fujisaka 5 Watanabe et al. 1968 cms-1d
O. sativa Tadukan Norin 8 Kitamura 1962 cms-TA
O. sativa A Chinese strain Fujisaka 5 Katsuo & Mizushima 1958 cms-CW
f.spontanea
O. sativa "Wild abortive" (Several) Lin & Yuan 1980 cms-WA
f. spontanea
O. sativa "Red awned wild" Lien-Tong-Tsao, etc. Lin & Yuan 1980 cms-HL
f. spontanea
O. sativa Akebono O. glaberrima Yabuno 1977 cms-ak
Additional sources not presented in RGN 1
O. rufipogon W1080(India) Taichung 65 Shinjyo et al. 1981 cms-W18
O. rufipogon W1090(India) Taichung 65 Shinjyo & Montomura 1981 cms-W19
O. rufipogon KR 7 Taichung 65 Cheng & Huang 1979 cms-KR
O. sativa Ya Cheng Guang Xuan 3 cf.Virmani & Wan 1988 cms-YC
f. spontanea
O. sativa Tian Dong Zhen Shan 97 cf.Virmani & Wan 1988 cms-TD
f. spontanea
O. sativa Lie Zhou Zhen Shan 97 cf.Virmani & Wan 1988 cms-LZ
f. spontanea
O. sativa Indian Jin Nan Te 43 cf.Virmani & Wan 1988 cms-IN
f. spontanea
O. sativa Dong Pu Jin Nan Te 43 cf.Virmani & Wan 1988 cms-DP
f. spontanea
O. sativa Jun Niya Chao Yang 1 cf.Virmani & Wan 1988 cms-JNY
f. spontanea
O. sativa He Pu Li Ming cf.Virmani & Wan 1988 cms-HP
f. spontanea
O. sativa Teng Qian Er-Jin-Qing cf.Virmani & Wan 1988 cms-TQ
f. spontanea
O. sativa San Ya Jing Yin 1 cf.Virmani & Wan 1988 cms-SY
f. spontanea
O. sativa Rao Ping 6964 cf.Virmani & Wan 1988 cms-RP
f. spontanea
O. sativa Guangzhou 6964 cf.Virmani & Wan 1988 cms-GZ
f. spontanea
O. sativa Dwarf aborted Xue Qin Zhao cf.Virmani & Wan 1988 cms-DA
f. spontanea
O. sativa Taichung N1 Pankhari 203 Athwal & Virmani 1972 cms-TN
O. sativa Gambiaca Chao Yang 1,etc. Lin & Yuan 1980 cms-GAM
O. sativa Birco(PI279120) Calrose Erickson 1969 cms-BI
O. sativa ARC 13829-16 IR10179-2-3-1 IRRI 1986 cms-ARC
O. sativa E Shan Ta Bei Cu Hong Mao Ying cf.Virmani & Wan 1988 cms-STB
O. sativa Tian Ji Du Fujisawa 5 cf.Virmani & Wan 1988 cms-TJD
O. sativa IR 24 Xiu Ling cf.Virmani & Wan 1988 cms-IR24
O. sativa Jing Chuan Nao Nan Tai Geng cf.Virmani & Wan 1988 cms-JCN
O. sativa Sheng Qi Nong Ken 8 cf.Virmani & Wan 1988 cms-SQ
O. sativa Li Up Jing Yin 83 cf.Virmani & Wan 1988 cms-LU
O. sativa Zhao Jin Feng Lan Bery cf.Virmani & Wan 1988 cms-ZJF
O. sativa Zhao Tong Bei Ke Ching 3 cf.Virmani & Wan 1988 cms-ZTB
O. sativa Dissi Hatif Zhen Shan 97 Wan et al. 1988 cms-DIS
===============================================================================
===============================================================================
Symbol used Source cms line restored Reference New symbol
by author suggested
===============================================================================
Genes reported in RGN 1
Rf-1 Chinsurah boro II (cms-bo) in Taichung 65 Shinjyo 1969 Rf-1
Rf-2 Fukuyama (cms-ld) in Fujisaka 5 Shinjyo and Rf-2
Watanabe 1977
Rf-j Akebono (cms-ak) in Yabuno 1977 Rf-ak
O. glaberrima W0440
Rf-a,b,c H103 (Linkage (cms-bo) in Taichung 65 Maekawa 1982 Complementary
tester Hokkaido restoring
genes, not
Univ.) identified
Rf-a', H406 (") " " "
bÕ,cÕ,dÕ
Genes not presented in RGN 1
Rf\1\ IR 24, IR 36 etc. (cms-WA) in Zhou et al. 1983 Rf-WA-1(t)
or R\1\ Zhen Shan Yang and Lu 1984
97A, etc. Virmani 1986
Rf\2\ or R\2\ " " " Rf-WA-2(t)
(At least these two genes are
necessary for restoration.)
===============================================================================
Athwal, D.S. and S.S. Virmani, 1972. Cytoplasmic male sterility and hybrid breeding in rice. In IRRI (ed.), Rice Breeding, pp. 615-620. IRRI, Manila.
Carnahan, H.L., J.R. Erickson, S.T. Tseng and J.N. Ruger, 1982. Outlook for hybrid rice in the USA. In IRRI (ed.), Rice Breeding, pp. 603-607. IRRI, Manila.
Cheng, Y.K. and C.S. Huang, 1979. Studies on cytoplasmic-genetic male sterility in cultivated rice (Oryza sativa L.), I. Effect of different cytoplasm sources on male abnormalities at anthesis. J. Agric. Assoc. China 106: 11-22.
Erickson, J.F., 1969. Cytoplasmic male sterility in rice (Oryza sativa L.). Agron. Abstr., p. 6.
Govinda Raj, K. and S.S. Virmani, 1986. Allelism test for restorer genes of six promising IR restorer lines. RGN 3: 93-94.
Katsuo, K. and U. Mizushima, 1958. Studies on the cytoplasmic difference among rice varieties, Oryza sativa L. Jpn. J. Breed. 8: 1-5 (Japanese/English)
Kitamura, E., 1962. Studies on cytoplasmic sterility of hybrids in distantly related varieties of rice, Oryza sativa L. 1. Fertility of the F\1\ hybrids between strains derived from certain Philippine x Japanese varietal crosses and Japanese varieties. Jpn. J. Breed. 12: 81-84. (Japanese/English)
Lin, S.C. and L.P. Yuan, 1980. Hybrid rice breeding in China. In IRRI (ed.), Innovative Approaches to Rice Breeding, pp. 35-51. IRRI, Manila.
Maekawa, M., 1982. Studies on genetical differences between distantly related rice varieties. Memoirs Fac. Agric. Hokkaido Univ. 13(2):146-177. (Jap./Eng.)
Oka, H.I, 1988. Origin of Cultivated Rice. Elsevier; Jpn. Sci. Soc. Press, 254 pp.
Shinjyo, C., 1969. Cytoplasmic genetic male sterility in cultivated rice, Oryza sativa L. II. The inheritance of male sterility. Jpn. J. Genet. 44: 149-156.
Shinjyo, C., 1975. Genetical studies of cytoplasmic male sterility and fertility restoration in rice, Oryza sativa L. Sci. Bull. Coll. Agric. Univ. Ryukyus 22: 1-51.
Shinjyo, C., 1984. Cytoplasmic male sterility and its use in breeding hybrid rice. Recent. Adv. Breed. Res. 25: 98-108. (in Japanese)
Shinjyo, C., and T. Omura, 1966. Cytoplasmic male sterility in cultivated rice, Oryza sativa L. I. Fertilities of F\1\, F\2\ and offspring obtained from their mutual reciprocal backcrosses and segregation of completely male sterile plants. Jpn. J. Breed. 16 (Suppl. 1): 179-180. (in Japanese)
Shinjyo, C., R. Nishime and Y. Watanabe, 1974. Inheritance of fertility- restoring genes Rf\x\ and Rf in male-sterile cytoplasm derived from variety lead rice. Jpn. J. Breed. 24 (Suppl. 1):130-131. (in Japanese)
Shinjyo, C., and Y. Watanabe, 1977. Allelism test of two genes showing fertility-restoring effect for male sterile cytoplasm of Lead rice and their inheritance. Jpn. J. Breed. 27 (Suppl. 2):70-71. (in Japanese)
Shinjyo, C., Y. Ishimura and M. Tanaki, 1981. Inheritance of male sterility in isogenic lines of Taichung 65 possessing male-sterile cytoplasm and fertility- restoring gene of Oryza perennis W1080 strain. Jpn. J. Breed. 31 (Suppl. 1):238-239. (in Japanese)
Shinjyo, C., and K. Motomura, 1981. Inheritance of male sterility in isogenic lines of Taichung 65 possessing male-sterile cytoplasm and fertility-restoring gene from Oryza perennis W1080 strain. Jpn. J. Breed. 31 (Suppl. 1):240-241. (in Japanese)
Virmani, S.S., K. Govinda Raj, C. Casal, R.D. Dalmacio and P.A. Aurin, 1986. Current knowledge of and outloock on cytoplasmic-genetic male sterility and fertility restoration in rice. In IRRI (ed.), Rice Genetics, pp. 633-647. IRRI, Manila.
Virmani, S.S., and Bang-Hui Wan, 1988. Development and use of diverse cytoplasmic male sterile lines in hybrid rice breeding. Proc. Intern. Symp. on Hybrid Rice, Changsha, Oct. 6-10, 1986. (in press)
Wan, B.H., D.M. Li and Q.H. Xuan, 1988. Classification of male sterile cytoplasms in rice. Proc. Intern. Symp. on Hybrid Rice, Changsha, Oct. 6-10, 1986. (in press)
Watanabe, Y., 1971. Establishment of cytoplasmic and genetic male-sterile lines by means of Indica-Japonica cross. Oryza (Cuttack) 8 (2, Suppl.):9-16.
Watanabe, Y., S. Sakaguchi and M. Kudo, 1968. On the male-sterile rice plant possessing the cytoplasm of Burmese variety, Lead rice. Jpn. J. Breed. 18 (Suppl. 2):77-78. (in Japanese)
Yabuno, T., 1977. Genetic studies on the interspecific cytoplasm substitution lines of Japonica varieties of Oryza sativa L. and O. glaberrima Steud. Euphytica 26: 451-463.
Yang, R.C. and H.R. Lu, 1984. A preliminary analysis of restoring genes in restoring line IR24 of rice. Acta Agron. Sinica 10: 81-86. (Chinese/English)
Zhou, T.L., J.H. Shen and F.C. Ye, 1983. A genetic analysis on the fertility of Hsien type hybrid rice with wild rice cytoplasm. Acta Agron. sinica 9(4):241- 247. (Chinese/English)
2. Gene symbols for leaf and culm traits
Osamu Kamijima-1 and Koh-ichi Mori-2
1)Faculty of Agriculture, Kobe University, Nada-ku, Kobe, 657 Japan
2)Faculty of Agriculture, Hokkaido University, Sapporo, 060 Japan
Spontaneous and induced mutants modifying leaf and culm traits so far reported
are about 40 not including dwarfing ones. The genes detected in these mutants
are listed in Table 1, with the linkage groups to which they belong and
references describing the genes. For some traits on which a number of articles
have been published, a few seemingly comprehensive papers are given as
references. The gene symbols given in the table are in principle due to those
proposed by respective authors, although some of them have been revised or
renumbered by the convener of the Committee (cf. RGN 1-4). In such cases, the
original symbols are shown in parenthesis.
For the brittleness of leaf and culm, four genes (bc-1 to bc-4) have been found (Table 1). The linkage groups to which they belong were made clear for three of them.
For the angle of tiller growth with the ground, two genes, la and Er, belonging to linkage groups VIII and VI+IX, respectively, have been known. In the lazy plants with la, tillers grow almost horizontally. The plants with Er grow open tillers (the angle is about 60 degrees), and its recessive allele, er, confers erect growth habit. There is another report that the spreading or erect habit is conditioned by a main gene (Es) and its inhibitor (I-Es) in crosses of an Indica variety Pankaj (Tripathi and Balakrishna Rao 1985).
With regard to the morphology of culms, several genes are known, i.e., eui for a specific elongation of uppermost internode, fc for fine culm, rcn for reduced culm number, etc. (Table 1). The eui gene promoting elongation of the first internode may be useful for promoting outcrossing (Rutger and Carnahan 1981). The rcn-1 gene reduced culm number under low temperature conditions, but does not affect tillering when temperature is high enough (Takamure and Kinoshita 1985).
Genes modifying the anatomical structure of stems were reported by Sethi and Roy (1984). Complementary genes Esb-1 and Esb-2 produce an extra sclerenchymatous band in the stem. The occurrence of "fuscoid cells", which are the cells with big vacuoles occurring on either side of the vascular bundle, was controlled by a dominant gene. This gene may be symboled Fsc as the authors' symbol Fc refers to fine culm.
Several genes are found controlling the hairiness of leaves, i.e., the glabrous genes (gl-1 and gl-2, duplicate), the hairy leaf genes (Hl-1 and Hl-b, complementary), and the heavy pubescence genes (Lh-a and Lh-b, complementary). These genes affect the hairiness of the hulls also. On the other hand, gene Hg confers hairiness only on the hulls (Nagao and Takahashi 1963).
Leaf characters are controlled by a number of genes. Six genes, nal-1 to Nal-6, are known to exhibit the narrow leaf character. The rolled leaf is controlled by five genes, rl-1 to rl-5. For the "dripping-wet" leaf, eight genes, drp-1 to drp-8 have been detected (Table 1).
In addition to the morphological traits mentioned above, the deepwater tolerance or floating habit may also be considered as a character of stem, although it is not included in Table 1. It depends on the capacity of internodes to elongate in reponse to gradual submergence before floral initiation, and is associated with several related responses like nodal branching and nodal rooting. Two genes, dw-1 and dw-2, were found for this character, and the former appeared to belong to linkage group X set up by Misro (1981) in Indica varieties. A genetic experiment conducted in Thailand showed that this character was controlled by a major (dominant) and several minor genes (Supapoj et al. 1977). Tripathi and Balakrishna Rao (1985) reported that floating ability concerned not only internode elongation to cope with the ascending water level, but also early nodal branching and nodal rooting, and that the latter two characters were controlled by genes Nd and Nr, respectively, which were linked with a gene for awn development (An) and a gene for tillering habit (Es). Floating ability is a complex, and relevant genes would be various.
We are indebted to Dr. H.I. Oka for his critical reading of the manuscript.
Table 1. List of genes for leaf and culm traits
===============================================================================
Trait Gene Linkage Reference/Remark
group
===============================================================================
Auricleless aul II Librojo & Khush 1986
Brittle culm bc-1 XI Nagao & Takahashi 1963; Iwata
& Omura 1971b
bc-2 Takahashi et al. 1968
bc-3 X Iwata & Omura 1977
bc-4 I Librojo & Khush 1986
Drooping leaf dl(lop) XI Mori et al. 1973;Iwata et al.1978
Dripping-wet leaf drp-1 II Nagao et al. 1964
drp-2 VII Iwata & Omura 1971a
drp-3 XI Iwata & Omura 1985
drp-4 XI Iwata & Omura 1985
drp-5(t) II Satoh et al. 1983
drp-6(t) III or I Satoh et al. 1983
drp-7 VIII Satoh et al. 1983
drp-8(t) II Satoh et al. 1983
Erect growth habit er(o) VI+IX Takahashi et al. 1968
Extra sclerenchyma- Esb-1 Sethi & Rao 1984/Complementary genes
tous band (in stem) Esb-2 Sethi & Rao 1984/Complementary genes
Elongated uppermost eui VI+IX Rutger&Carnahan 1981;Maekawa&Kita 1983
internode
Fine culm fc-1 XI Iwata & Omura 1977;Iwata et al.1978
fc-2(t) I or III Satoh et al. 1983
Fuscoid cell Fsc(Fc) Wethi & Rao 1984
Glabrous leaf gl-1 VI+IX Nagao&Takahashi 1963; Iwata & Omura
and hull 1976;
gl-2 Sato et al.1982/Duplicate genes
Hairy leaf Hl-a I Nagao&Takahashi 1963;Iwata et al. 1978
Hl-b Nagao&Takahashi 1963;Iwata et al. 1978
Lazy growth habit la VII Nagao&Takahashi 1963;Iwata et al. 1978
Heavy pubescence Lh-a Anonymous 1963/Complementary genes
Lh-b Anonymous 1963/Complementary genes
Liguleless lg II Nagao&Takahashi 1963;Iwata & Omura 1971b
Narrow leaf nal-1 II Mori et al.1973/Duplicate or triplicate genes
nal-2 VIII Mori et al.1973/Duplicate or triplicate genes
nal-3(nal-2)* d-33 Iwata & Omura 1975; Yoshimura et al. 1982
nal-4(nal) II Yen et al. 1968
nal-5(nal-1)* II Iwata & Omura 1977
Nal-6(t) XI Iwata et al. 1985
Reduced culm rcn-1 I Takamure & Kinoshita 1985
number
rcn-2 Takamure & Kinoshita 1987
Rolled leaf rl-1 III Nagao et al. 1964
rl-2 II Mori et al. 1973
rl-3(rl-1)* Iwata & Omura 1975;Yoshimura et al. 1982
rl-4(rl-2)* III Iwata & Omura 1977;Iwata et al. 1979a
rl-5(rl-3)* XI Iwata et al. 1979b
Root growth inhibition rt Kitano & Futsuhara 1986
Twisted stem ts-z III Hsieh 1960/Complementary genes
ts-b Hsieh 1960
==============================================================================
*Numbering used in Kyushu University
==============================================================================
Anonymous, 1963. Rice gene symbolization and linkage groups. U.S.D.A. Agr. Res. Service 34-38, pp. 56.
Hsieh, S.C., 1960. Genic analysis in rice, I. Coloration genes and inheritance of other characters in rice. Bot. Bull. Acad. Sinica 1(2): 117-132.
Iwata, N. and T. Omura, 1971a. Linkage analysis by reciprocal translocation method in rice plants, II. Linkage groups corresponding to chromosomes 1,2,3 and 4. Jpn. J. Breed. 21: 19-28. (Japanese/English)
Iwata, N. and T. Omura, 1971b. Ditto, II. Linkage groups corresponding to chromosomes 5,6,8,9,10 and 11. Sci. Bull. Fac. Agr. Kyushu Univ. 25: 137-153. (Japanese/English)
Iwata, N. and T. Omura, 1975. Studies on the trisomics in rice plants, III. Relation between trisomics and genetic linkage groups. jpn. J. Breed. 25(6):363-368.
Iwata, N. and T. Omura, 1976. Ditto, IV. On the possibility of association of three linkage groups with one chromosome. Jpn. J. Genet. 51: 135-137.
Iwata, N. and T. Omura, 1977. Linkage studies in rice. On some mutants derived from chronic gamma irradiation. J. Fac. Agr. Kyushu Univ. 21: 117-127.
Iwata, N., T. Omura and H. Satoh, 1978. Linkage studies in rice. The sequence of genes at the eighth and eleventh linkage groups. Jpn. J. Breed. 28 (Suppl. 1): 170-171. (in Japanese)
Iwata, N., H. Satoh and T. Omura, 1979a. Linkage studies in rice. On some genes described newly which belong to the third linkage group. Jpn. J. Breed. 29 (Suppl. 1): 234-235. (in Japanese)
Iwata, N., H. Satoh and T. Omura, 1979b. Linkage studies in rice. New genes belonging to the 11th linkage group. Jpn. J. Breed. 29 (Suppl. 2): 182-183. (in Japanese)
Iwata, N., H. Satoh and T. Omura, 1985. Linkage studies in rice. On the loci of some marker genes locating on chromosome 5. Jpn. J. Breed. 35 (suppl. 1): 204- 205. (in Japanese)
Kitano, H. and Y. Futsuhara, 1986.Character expression of a root growth inhibiting mutant in rice. RGN 3: 97-99.
Librojo, A.L. and G.S. Khush, 1986. Chromosomal location of some mutant genes through the use of primary trisomics in rice. In Rice Genetics, pp. 249-255. IRRI, Manila.
Maekawa, M. and F. Kita, 1983. Interaction of eui gene for the elongation of uppermost internode and some genes for the elongation of internodes. Jpn. J. Breed. 33 (Suppl. 1): 124-125. (in Japanese)
Misro, B., 1981. Linkage studies in rice, X. Identification of linkage groups in indica rice. Oryza (Cuttack) 18(4): 185-195.
Mori, K., T. Kinoshita and M. Takahashi, 1973. Linkage relationships of genes for some mutant characters of rice kept in Kyushu University. Genetical studies in rice plant, 55. Mem. Fac. Agr. Hokkaido Univ. 8(4): 377-385.
Nagao, S. and M. Takahashi, 1963. Trial construction of twelve linkage groups in Japanese rice. Genetical studies on rice plant, 28. J. Fac. Agr. Hokkaido Univ. 53(1): 72-130.
Nagao, S., Takahashi, M. and K. Morimura, 1964. Causal genes and their linkage relationships of some morphological characters introduced from foreign rice varieites. Mem. Fac. Agr. Hokkaido Univ. 5(2):89-96. (Japanese/English)
Rutger, J.N. and H.L. Carnahan, 1981. A fourth genetic element to facilitate hybrid cereal production -A recessive tall in rice. Crop Sci. 21: 373-376.
Sato, S., K. Muraoka and Y. Sano, 1982. Reconstruction of a linkage group corresponding to Nishimura's second chromosome in rice. Jpn. J. Breed. 32(3): 232-238.
Satoh, H., N. Iwata and T. Omura, 1983. Gene analysis of some dripping-wet leaf mutants in rice. Jpn. J. Breed. 33 (Suppl. 2):242-243. (in Japanese)
Sethi, M. and J.K. Boy, 1984. Inheritance of two anatomical characteristics. RGN 1: 108.
Supapoj, N., C. Setabutara, K. Kupkanchanakul and F. Shuwisitkul, 1977. Segregation for elongating ability in two crosses of floating rice with ordinary lowland rice. In Deepwater Rice, pp. 29-36. IRRI, Manila.
Takahashi, M., T. Kinoshita and K. Takeda, 1968. Character expression and causal genes of some mutants in rice plant. Genetical studies on rice plant, 33. J. Fac. Agr. Hokkaido Univ. 55(4):496-512.
Takamure, I. and T. Kinoshita, 1985. Inheritance and expression of reduced culm number character in rice. Jpn. J. Breed. 35: 17-24.
Takamure, I. and T. Kinoshita, 1987. Genic identification of the mutant genes for reduced culm number in rice. Jpn. J. Breed. 37 (Suppl. 1): 182-183. (in Japanese)
Tripathi, R.S. and M.J. Balakrishna Rao, 1985. Inheritance studies of characters associated with floating habit and their linkage relationship in rice. Euphytica 34: 875-887.
Yen, S.T., M.M. Lin and S.C. Hsieh, 1968. Linkage relations of another induced dwarfness genes, d\31\. Genic analysis in rice. Bot. Bull. Acad. Sinica 9(1): 69-74.
Yoshimura, A., N. Iwata and T. Omura, 1982. Linkage analysis by reciprocal translocation in rice plants, III. Marker genes located on chromosomes 2,3,4 and 7. Jpn. J. Breed. 32(4) 323-332.