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SUMMARYOriginal seedstocks, populations developed by recurrent selection, and inbred lines of two green curded cauliflowers, Di Macerata and Romanesco, were compared in two adjacent but independent trials at Wellesbourne. Trial results indicate that recurrent selection and inbreeding had generally led to significant improvement in uniformity of maturity, increased marketable yield, and improved quality characters contributing to overall appearance and marketability of the product. Depending on the strength of self incompatibility, inbred lines derived from improved populations could potentially be used as varieties, or as parental lines for hybrids. 相似文献
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Ilias D. Avdikos Nektaria Tsivelika Athanasia Gallidou Metaxia Koutsika-Sotiriou Ekaterini Traka-Mavrona 《Scientia Horticulturae》2011
This paper presents the efficiency of recurrent selection in the segregating generations of recycled lines, obtained via mass selection, in two tomato commercial single-cross hybrids, and the assessment of advanced lines in two farming systems at two different locations. In particular, in the F3 and F4 mass selection lines of the hybrids Iron and Sahara, half-sib (HS) selection was applied by crossing within the F3 and F4 plants. Two experiments were conducted, the first for evaluating the F4 mass lines with the HS lines obtained by crossing in the F3 generation, and the second for evaluating the F5 mass lines with the HS lines obtained by crossing in the F4 generation, and the second generation HS lines, which were selected from the first experiment. F1 and F4 generations were used as controls, respectively. The HS lines of cv. Sahara overyielded 18–56% the F4 mass line, while Iron's HS lines presented greater uniformity in yield components and also outperformed qualitatively. The effectiveness of mass selection showed positive realized heritability only for fruit number of cv. Iron. In this study, where evaluation and selection was practiced in the absence of competition, the expected response in heterosis via HS depended on σ2g. The differences of σ2g of F1 from mass and HS lines were positive for both hybrids, while when the control was the F4 generation, mass lines showed a lower performance and some HS lines showed a higher performance. This means that HS lines have favorable alleles and heterosis. In this sense, Sahara's and Iron's HS lines increased 50.2 and 5.3% the charge of favorable alleles, respectively, compared to the corresponding control. The selected advanced lines were assessed in two farming systems at two different locations; the organic one, where two HS-lines, one from each hybrid, outyielded significantly the control; and the conventional one, where all lines performed equally to the control. The results assume the evidence that stable hybrids incorporate individual buffering into inbred line cultivars. 相似文献
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碧绿1号是以胞质雄性不育系CMS9507为母本,以自交系9355为父本配制而成的青花菜一代杂种。中晚熟,从定植到收获80 d（天）左右;花球紧实,半圆球形,无荚叶,花蕾细小,绿色,主茎不易空心,单球质量400 g 左右;高抗TuMV,抗黑腐病,每667 m2 产量1 000 kg 左右。 相似文献
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Veerendra K. Verma T.K. Behera A.D. Munshi Swarup K. Parida T. Mohapatra 《Scientia Horticulturae》2007
Ten inbred lines of ash gourd [Benincasa hispida (Thunb.) Cogn.] were crossed to produce 45 F1 hybrids (without reciprocal) which were evaluated along with the parents for 20 growth- and yield-related traits, in a replicated field trial. High level of heterosis was observed among the hybrids for most of the traits examined, including yield. These inbred lines were analysed by using 42 RAPD primers those produced 282 DNA marker bands. A total of 130 RAPD markers were obtained with a mean of 3.1 per primer, which in combination discriminated all the inbreds from each other. Pair-wise genetic distance measurements ranged from 0.07 to 0.31, suggesting a wide genetic diversity for these inbreds. These inberds were also analysed with five ISSR primers of which four were informative. Twenty-six ISSR marker bands were generated of which 11 were polymorphic with an average of 2.80 per primers. The percentage of polymorphic bands produced were higher in ISSR markers (>80%) than generated through RAPD markers (46%). Although the results indicated significant positive correlations of genetic distance with hybrid performance and heterosis, the RAPD based genetic distance measures and use of limited ISSR markers in this present study could not effectively predict hybrid performance in this crop. The genetic variation among ash gourd inbred lines examined, herein, defined a marker array (combined ISSR and RAPD) for the development of a standard reference for further genetic analyses, and the selection of potential parents for predicting hybrid performance and heterosis. 相似文献
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Xiaoyin Lian Gangjun Luo Hui Li Wenji Xu Yuee Xiao 《The Journal of Horticultural Science and Biotechnology》2016,91(5):483-490
Previously, we found that reciprocal F1 hybrids of purple-flowered Iris dichotoma and I. domestica were different. To further characterize this reciprocal difference, we carried out reciprocal crosses between three different colours of I. dichotoma and I. domestica. Morphological and cytological characters of F1 hybrids of six interspecific crosses between three different colours of I. dichotoma and I. domestica (three direct and their three reciprocals) were evaluated. The results showed that the fruit-setting rates of three different colours of I. dichotoma as female and I. domestica as male were lower than reciprocal cross combinations, but their seed germination rates were significantly higher than reciprocal ones. Reciprocal differences of F1 hybrids were observed for most morphological characters. The F1 hybrids of three different colours of I. dichotoma as female were totally different from their parents; however, the F1 hybrids of I. domestica as female were extremely similar to the mother. The six interspecific hybrids had the same chromosome number (2n = 32) as their parents. Reciprocal differences were detected for karyotype. Parents’ and F1 hybrids’ karyotypes focused on 1A to 2B. In these cases, the direction of the cross must be kept in mind in order to improve the efficacy of future breeding programmes. 相似文献
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黄瓜嫩果皮颜色的遗传研究 总被引：2，自引：0，他引：2
以2 个嫩果皮颜色不同的黄瓜自交系为试验材料,通过目测分类、色彩色差仪测定果皮色L
值和C 值,并利用P1、P2、F1、B1、B2 和F2 等6 个世代联合分析方法,研究了黄瓜嫩果皮颜色的遗传规
律。结果表明：黄瓜嫩果皮颜色性状符合两对加性-显性-上位性主基因 + 加性-显性-上位性多基
因模型（E-0 模型）;L 值和C 值F2 代主基因遗传力分别为93.61%和80.86%,遗传力较高;多基因遗传
力和环境效应都较低,在育种时对黄瓜嫩果皮颜色的选择应在早期分离世代进行。 相似文献
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T.K. Behera S.S. Dey A.D. Munshi Ambika B. Gaikwad Anand Pal Iqbal Singh 《Scientia Horticulturae》2009,120(1):130-133
Gynoecism has been used on a large scale in heterosis breeding of cucumber. Production of hybrid seeds in bitter gourd is highly expensive because it is done mainly through hand pollination. But utilization of a gynoecious line would be more economical and easier method. Since gynoecious parent has only female flowers, the open pollinated seeds it produces will be F1 hybrid. It will reduce the cost of male flower pinching and hand pollination. Two gynoecious lines, DBGY-201 and DBGY-202 were crossed with two monoecious cultivars, “Pusa Do Mausami” and “Pusa Vishesh” and their F2 populations were observed to determine the inheritance pattern of gynoecious sex form. Another experiment was conducted to determine magnitude of heterosis by utilizing nine inbred lines including one gynoecious line, DBGY-201 in diallel (without reciprocal) mating system. All the gynoecious hybrids showed significant heterosis in a desirable direction for traits like sex ratio (male:female), days to first picking, number of fruits per plant, yield per plant, and vine length. The segregation pattern in F2 suggested that gynoecious sex form in bitter gourd was governed by single recessive gene. The gynoecious hybrids DBGY-201 × “Pusa Vishesh” and DBGY-201 × “Pusa Do Mausami” were important for early harvest (～50 days after sowing) whereas DBGY-201 × “Priya” and DBGY-201 × “Arka Harit” were promising for higher yield. 相似文献
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The effects of cold-treating young cauliflower plants (Brassica oleracea var. botrytis L.) of the cultivars ‘Lero’, ‘Lawyna’, ‘Novo’ and ‘Janavon’, on gibberellin activity and the spreads of curd initiation and maturity are described and discussed in relation to other similar work.Exposure of plants to 0°C for 15 days increased gibberellin activity in the apices of ‘Lero’ and ‘Lawyna’ plants. The spreads of curd initiation and maturity of ‘Lawyna’ were significantly reduced by cold-treatment at 0°C, but ‘Lero’ was not affected, possibly because plants had initiated too many leaves and were thus beyond the stage receptive to low-temperature treatment. This treatment had no effect on gibberellin activity nor on the spreads of curd initiation and maturity of ‘Novo’ or ‘Janavon’, probably because plants had not reached the sensitive stage when cold-treated.It is postulated that the phase of growth during which the curd-initiation period can be shortened by cold treatment is specific for each cultivar, and other data were used to confirm this. It seems likely that the receptive phase occurs at higher leaf-numbers with cultivars which take longer to initiate curds. 相似文献
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