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Abstract Analysis of the glucosinolate content and composition by high-pressure liquid chromatography indicated that varieties of Brassica juncea bred and grown in India have a high glucosinolate content characterized by the presence of 2-propenyl (allyl) and 3-butenyl as the major and 4-pentenyl as the minor fractions. In contrast, the B. juncea germplasm from other countries is characterized by the presence of 2-propenyl as the major glucosinolate fraction, trace amounts of 3-butenyl and a total lack of the 4-pentenyl types. In order to transfer the low glucosinolate trait to Indian B. juncea , the inheritance of total glucosinolates was investigated using doubled haploid (DH) populations derived from F1 (DH1 ) and BC1 (BC1 DH) of a cross between ‘Varuna’ (the most widely cultivated high glucosinolate variety of India) and ‘Heera’ (a non-allyl type low glucosinolate line). A total of 752 DH1 and 1263 BC1 DH gave rise to seven and 11 low glucosinolate (containing less than 18 µmol/g seed) individuals, respectively. On the basis of the frequency of the low glucosinolate individuals, the total glucosinolate was found to be under the control of seven genes. There was presence of both allyl and non-allyl types in DH1 and BC1 DH low-glucosinolate individuals and absence of 3-butenyl glucosinolate in some of the BC1 DH low glucosinolate individuals, indicating segregation for these fractions in the population. The size of the segregating DH population proved to be crucial for precise determination of the number of genes controlling the trait. Because of the large number of genes involved, incorporation of low glucosinolate trait in Indian B. juncea should be approached through doubled haploid (DH) breeding. [ABSTRACT FROM AUTHOR]

Eighteen genotypes of Brassica napus were crossed to a cytoplasmic male sterile (CMS) line of B. napus BO15 carrying B. tournefortu cytoplasm ('tour' cytoplasm). Fourteen genotypes were found to be stable maintainers of the 'tour' CMS. Of the remaining four genotypes, GSL-1 and 'Asahi-natane' were found to be heterozygous and 'Mangun' and 'Yudal' were homozygous for the restorer gene. Analysis of the F[SUB1] and F[SUB2] progenies of (CMS) BO15 × 'Mangun' and (CMS) BO15 × 'Yudal' showed that fertility restoration is controlled by a single dominant gene.The availability of a number of stable maintainer lines and the simple inheritance pattern of fertility restorer gene makes 'tour' CMS a useful system for hybrid seed production in rapeseed. [ABSTRACT FROM AUTHOR]

'Polima' cytoplasmic male sterility (CMS) was transferred to three different genotypes of B. napus i.e. GSL-1, ISN706 and HNS-8 by repeated backcrossing and was found to be completely stable in the nuclear background of synthetic B. napus genotype, ISN706, derived from a cross B. campestris ssp. oleifera var. brown sarson × B. oleracea var. botrytis cv. 'Pusa Katki'. The BC[SUB5] and BC[SUB6] generation lines of ISN706, GSL-1 and HNS-8 with 'Polima' CMS were grown under a range of temperature and photo-period conditions to test their stability. No breakdown in sterility was observed in 'Polima' ISN706 and, therefore, this genotype can be used as a maintainer for hybrid seed production. [ABSTRACT FROM AUTHOR]

Chloroplast (cp) and mitochondrial (mt) DNA restriction profiles of a cytoplasmic male sterile (CMS) line of Brassica juncea and its maintainer line were compared and found to be markedly different. Comparison of cpDNA restriction profiles of fifty different species of genus Brassica and some allied genera showed that the cpDNA profiles of CMS lines were similar to that of B. tournefortii for twenty different restriction endonucleases. This CMS system is thus not of spontaneous origin as reported earlier, but is alloplasmic in nature. Comparison of restriction profiles of mtDNA of B. tournefortii and CMS lines revealed some differences which might either be due to changes in DNA pattern during the transfer, or, due to the cytoplasm coming from a B. tournefortii line different from the one used in this study. [ABSTRACT FROM AUTHOR]

The objective of this study was to broaden the genetic base in oleiferous Brassica juncea by resynthesis, using 10 diverse parental lines of oleiferous B. rapa and two lines of B. nigra of both Indian and exotic origin. Out of 14 crosses attempted using B. rapa as the female parent, eight were successful. Embryo rescue was necessary to obtain interspecific plants. A total of 29 fertile interspecific plants were obtained after colchicine treatment. In the S2 generation, the expression of component characters in the majority of the resynthesized plants showed a negative trend. The resynthesized B. juncea lines are being maintained through repeated selfing and selection at each generation for desirable plant types. This process will continue till the progeny lines of the desirable plants achieve uniformity. [ABSTRACT FROM AUTHOR]

Brassica carinata (BBCC), a potential oilseed crop for dry land agriculture, is sensitive to high temperatures during germination and early stages of growth, which thereby restricts the possibility of using the residual soil moisture available after the rainy season for its cultivation. To overcome this problem, a three-genome hybrid, RCBB, was synthesized using Raphanus sativus (RR) and Brassica oleracea (CC) as donor sources for the desired heat tolerance. Protoplasts of RC hybrids obtained through sexual crosses between R. sativus (female) and B. oleracea (male) were fused with protoplasts of Brassica nigra (BB) to produce RCBB somatic hybrids. The hybrid colonies regenerated with an average frequency of 7.6%. Twelve out of 36 hybrids grown to maturity were characterized for their nuclear and organelle genomes. While all the hybrids showed the presence of B. nigra chloroplasts, 10 of the hybrids showed B. nigra -specific mitochondria and two had Raphanus -specific mitochondria. The somatic hybrids could be backcrossed to B. carinata . [ABSTRACT FROM AUTHOR]

‘Polima’ cytoplasmic male sterility (CMS) was transferred from ‘Polima’ Brassica napus ‘ISN 706’ to five different cultivars of Brassica campestris (‘Pusa kalyani’, ‘Pant toria’, ‘Candle’, ‘Tobin’ and ‘ATC 94211’) by repeated backcrossing. It was observed that, while ‘Polima’ CMS manifested complete and stable male sterility in the nuclear backgrounds of ‘Pusa kalyani’, ‘Pant toria’, and ‘Tobin’, the cultivars ‘Candle’ and ‘ATC 94211’ possessed the restorer gene for this CMS in the heterozygous condition. An analysis of F1 and F2 generations of ‘Polima’ ‘Pusa kalyani’ × ‘Candle’ and ‘Polima’ ‘Pusa kalyani’ × ‘ATC 94211’ revealed that restoration is controlled by a single dominant gene. Identification of stable maintainers and restorers of ‘Polima’ CMS could facilitate the development of hybrid varieties in B. campestris. [ABSTRACT FROM AUTHOR]