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O. Banga 《Euphytica》1957,6(1):11-13
Summary Since the 16th century horticulture developed relatively early and rapidly in the Netherlands, and in the growing centres of vegetables and ornamentals a great number of highly improved varieties were produced by professional growers. A number of new fruit varieties was raised by professional men or by amateurs.During the last ten or twenty years science is being incorporated more and more into horticultural plant breeding. In ornamentals and vegetables this takes the form of cooperation between professional breeders and scientific institutions, in fruit the breeding work is mainly done by institutions.  相似文献   
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O. Banga  J. Petiet 《Euphytica》1958,7(1):21-30
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    By means of test crossings to American male sterile varieties N ms ms plants were found in Netherlands onion varieties.  相似文献   
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Cytoplasmic male sterility (CMS) system based on the cytoplasm from Moricandia arvensis (mori) was investigated for fertility restoration and agronomic potential. Fertility restorer gene for mori CMS was introgressed from cytoplasm donor species as all the evaluated Brassica juncea genotypes (155) acted as sterility maintainers. The allosyndetic pairing between Ma and the A/B genome chromosomes in the monosomic addition plants (2n= 18II + 1Ma) facilitated the gene introgression. Partial fertility restoration (43–52% pollen grain stainability) in F1 hybrids and absence of segregation for male sterility in F2 progenies suggested gametophytic control of fertility restoration. The pollen fertility in the F1 hybrids was, however, sufficient to ensure complete seed set upon bag selfing. Introgression from M. arvensis also helped in correction of chlorosis associated with mori cytoplasm in CMS and fertile alloplasmic B. juncea plants. Yield evaluation of thirty F1 hybrids having the same nuclear genotype but varied male sterilizing cytoplasms (mori, oxy, lyr, refined ogu), in comparison to respective euplasmic hand bred control hybrids, allowed an estimate of yield penalty associated with different CMS systems. It ranged from 1.8% to 61.6%. Hybrids based on cytoplasmically refined ogu were most productive followed by those based on cytoplasmically refined mori CMS. The male sterility systems emanating from somatic hybridization were found superior than those developed from sexual hybridization.  相似文献   
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Two wide hybrids, Diplotaxis erucoides (2n = 14) × Brassica rapa (2n = 20) and B. maurorum (2n = 20) × B. rapa, were developed using the sequential ovary–ovule culture. Reciprocal crosses failed, possibly as a consequence of strong unilateral incompatibility. The F 1 hybrids in each combination were completely male sterile and morphologically intermediate to the respective parents. DNA marker polymorphism and chromosome counts confirmed their hybrid nature. High frequency of bivalents in the F 1 and the presence of trivalents/quadrivalents in the derived amphiploids suggested genomic duplications and homoeology of the parental genomes. Up to three homoeologous pairs between the D. erucoides (DeDe) and B. rapa (AA) genomes, and one between B. maurorum (BmBm) and B. rapa genomes were observed. Successful synthesis of the F 1 hybrids and amphiploids of B. rapa with D. erucoides and B. maurorum, and allosyndetic chromosome pairing are expected to permit introgressions of desirable loci into the cultivated Brassica germplasm, especially for resistance to Alternaria brassicae and Albugo candida.  相似文献   
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A diverse array of wild and weedy crucifers was screened under laboratory conditions for their resistance to Lipaphis erysimi (Kaltenbach) (Homoptera: Aphididae). Among these, Brassica fruticulosa and Brassica montana were found to be the most promising. The availability of a synthetic amphiploid, AD-4(B. fruticulosa × Brassica rapa var. brown sarson) as well as a set of Brassica juncea lines carrying genomic introgressions from B. fruticulosa allowed us to investigate B. fruticulosa resistance in greater detail. This assessment was carried out along with susceptible check B. rapa ssp. brown sarson cv. BSH-1 in a series of choice and no choice experiments. The mustard aphid showed maximum preference for feeding on BSH-1 while least preference was recorded for B. fruticulosa followed by AD-4 as evidenced by the number of aphids that settled on circular leaf bits of these genotypes 24 and 48 h after release in a choice experiment. Brassica fruticulosa exhibited strong antibiosis against mustard aphid in no choice experiment and all the released aphids died within 5–8 days of their release, while the maximum survival (76.7%) was recorded on BSH-1. The survival on AD-4 (40%) was significantly lower than that on BSH-1. Almost similar trend was observed with respect to other demographic parameters of L. erysimi viz. development time, fecundity and longevity. In the screen house studies, there was no seedling mortality in B. fruticulosa and AD-4 after 30 days of aphid release while 80% mortality was observed on BSH-1. Excellent variation for aphid resistance was recorded in B. juncea introgression lines, emphasizing heritable nature of fruticulosa resistance. The biochemical analysis suggested the possibility of high concentration of lectins to be associated with low aphid infestation in B. fruticulosa.  相似文献   
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O. Banga 《Euphytica》1961,10(1):49-58
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    Scorzonera is somewhat erratic in seed setting, but outdoor pollination is much better than pollination in glass structures. Selfing the plants by bagging some flowers of each plant together with flies did not give a lower seed setting than open pollination under the same conditions (see table 1). Vegetative propagation of Scorzonera-roots is relatively easy.  相似文献   
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