Inheritance mode of microsatellite DNA markers and their use for kinship estimation in kuruma prawn Penaeus japonicus

The allelic inheritance mode of microsatellite DNA markers was examined using seven copulated wild females and their offspring. Five microsatellite loci, CSPJ002 *, CSPJ010 *, CSPJ012 *, CSPJ014 *, and CSPJ015 *, were used in the study. At almost all family/locus combinations, one sire was determined and distributions of genotypes in offspring were consistent with the Mendelian segregation ratio. Distributions of genotypes were consistent with the ratio after assuming a null allele at some loci. Consequently, the alleles of CSPJ002 * and CSPJ012 * were inherited following the Mendelian inheritance mode in every family; however, the null allele was expected in CSPJ010 *, CSPJ014 *, and CSPJ015 * in some families. Thus, these loci should be used carefully in population genetic analysis, but siblings could be detected in the dendrograms based on unweighted pair-group method using arithmetic averages (UPMGA).     

A gamete abortion locus detected by segregation distortion of isozyme locus Est-9 in wide crosses of rice (Oryza sativa L.)

Summary A locus for male gamete abortion in hybrids for Japonica and Indica rice was identified with the aid of marker genes Rc and Est-9 on chromosome 7. In an Indica-Japonica cross, AKAMAI 1/IR50, the Indica allele Est-9 ² was transmitted via the male gamete with a ratio of 0.29 instead of the normal 0.5, whereas no segregation distortion was observed for the Rc locus. The recombination value (p) for Est-9 and Rc was estimated to be 0.38 by a least square method after adjusting Mendelian segregation ratios with the male transmission ratios of 0.29 (Tr) for Est-9 ² and 0.71 (1-Tr) for Est-9 ¹. The recombination value (q) for the new locus for male gamete abortion, ga-11, and Est-9 was estimated to be 0.23 by using 56 F₃ lines from F₂ plants which were heterozygous for the Est-9 locus. No linkage for Rc and ga-11 was found. Therefore, the two markers and ga-11 were located in the order of ga-11-Est-9-Rc. Using the estimated recombination value (q), the male transmission rate (k) of ga-11 ^a was estimated to be 0.11 with the F₂ data and-0.07 with the F₃ line data. Thus, it was apparent that male gametes possessing ga-11 ^a were frequently aborted in the Indica-Japonica hybrid.     

菜豆优良种质综合鉴定评价

对`七五 、`八五 期间入国家种质库菜豆资源性状鉴定中表现优良的3 8份菜豆资源进行了两年3试点田间综合鉴定评价,获得了4份矮生、2份蔓生优异材料可供菜豆生产和科研利用.     

Isozyme polymorphism in three gene pools of cultivated chicory (Cichorium intybus L.)

Summary Polymorphism of ten enzymes, acid phosphatase (APH), isocitrate dehydrogenase (IDH), leucine aminopeptidase (LAP), phosphorylase (PP), superoxide dismutase (SOD), malic enzyme (ME), glutamate oxaloacetate transaminase 1 and 2 (GOT-1, GOT-2) and phosphoglucomutase 1 and 2 (PGM-1 and PGM-2), was investigated in three gene pools of cultivated chicory, including six cultivated wild chccory, eight industrial chicory and eight Brussels chicory varieties. LAP, APH, PP and PGM-2 showed high phenotypic polymorphism whilst GOT-1 and ME had poor polymorphism. For three enzyme coding loci Lap, Pgm-1 and Got-2, allele frequencies were determined. Isozyme composition in the three chicory gene pools was significantly different, showing, respectively, high, intermediate and poor average amount of phenotypic polymorphism in cultivated wild chicory, industrial chicory and Brussels chicory. Isozyme variation within and between varieties of the three gene pools is discussed in relation to breeding practices.