Marker-assisted selection of low erucic acid quantity in short duration Brassica rapa

Low erucic acid (LEA) rapeseed, which has accumulated mutant fatty acid elongase genes at the BnFAE1.1 and BnFAE1.2 loci of the A- and C-genome, respectively, is an important oilseed crop. Short growing turnip rape (B. rapa) is also important as a catch crop in the continuous cropping of rice in Asia but there is no LEA B. rapa cultivar for cultivation in South Asia. In order to develop LEA turnip rape cultivars, high erucic acid turnip rape cultivars were interspecifically crossed as recurrent parents to a canola quality rapeseed. In the meantime, we monitored incorporation of the mutant bnfae1.1 (e1) gene into A-genome of turnip rape, using a dCAPS primer pair, which can amplify PCR fragment only for the mutant e1 gene from A-genome. The early backcross progenies showed poor seed set, but which was improved in advanced progenies. Finally, homozygous e1e1 genotypes were established in the selfed progenies of BC₂–BC₃, and their LEA content was confirmed by gas-chromatography analysis. Our results and promising lines will contribute to LEA-trait selection in turnip rape and rapeseed breeding.     

Histological Investigation of Pelvic Symphysis in Holstein-Friesian Cattle

Knowledge of the changes in cattle pelvic symphysis during gestation and obstetrics gives valuable information about the age of optimal primary calving of cows. The aim of the study was to investigate the histological changes of pelvic symphysis in Estonian Holstein-Frisian＇s （EHF） of different ages. Eight EHF cows up to five years of their age were divided into three age groups： calved, in-calved and after calved bovines. Material for histological and histochemical investigation was taken from four places： （1） cranial part ofpubic bone; （2） pubo-ischiadic junction; （3） symphyseal eminence; （4） body of the interischiadic bone. In all study-groups, the cranial part of pubic bone consisted of cartilage. In pubo-ischiadic junction of calves connective tissue proper, fibrous and hyaline cartilage were noted. In in-calved cattle with gestation of 4-5 months and in after calved cattle group hyaline cartilage and bone tissue were noted, however in in-calved cattle with gestation of 7.5 months fibrous cartilage and connective tissue proper prevalated. In sympyseal eminence of calves connective cartilage osseous tissue was present. The region of interischiadic tissue proper and cartilage were noted; in other groups besides bone of calves consisted of connective tissue proper and fibrous cartilage, meanwhile in in-calved and after calved EHF＇s in the region hyaline cartilage and osseous tissue prevalated. These preliminary results demonstrate that the main changes in the pelvic symphysis histology, retardation of ossification, of EHF kines occur during the second-half of gestation in the pubo-ischiadic junction.     

Co-Composting Urban Waste,Plant Residues,and Rock Phosphate: Biochemical Characterization and Evaluation of Compost Maturity

Co-composting of urban wastes (UWs) and plant residues with rock phosphate (RP) produces quality compost and reduces the use of chemical phosphorus fertilizer. Biochemical process of three compost piles (P): P₁- 50% UW + 30% rice straw (RS) + 10% sawdust (SD) + 8% RP + 2% sugarcane trash (ST), P₂- 50% UW + 23% RS + 10% SD + 15% mustard oil cake + 2% ST, and P₃- 95% UW + 5% RP was studied. Decomposition rate followed first-order kinetics and maximum (77%) was in P₃. The highest bacterial population was found in P₂ having higher cumulative CO₂ evolution (53.76 mg CO₂ g^?1 volume solid). Prevalence of phosphate-solubilizing bacteria was 2.0 to 6.3 Log₁₀ Cfu g^?1 dry weight and concentrated in RP-amended piles. Humic acid of compost was classified as rotteprudukte. Final pH (7.5 to 8.0) and germination index (>90) proved that the compost was mature. P₃ compost (1 t ha^?1, fresh weight) had potential to supply 25 kg phosphorus.     

Production of high yield short duration Brassica napus by interspecific hybridization between B. oleracea and B. rapa

Brassica napus is a leading oilseed crop throughout many parts of the world. It is well adapted to long day photoperiods, however, it does not adapt well to short day subtropical regions. Short duration B. napus plants were resynthesized through ovary culture from interspecific crosses in which B. rapa cultivars were reciprocally crossed with B. oleracea. From five different combinations, 17 hybrid plants were obtained in both directions. By self-pollinating the F₁ hybrids or introgressing them with cultivated B. napus, resynthesized (RS) F₃ and semi-resynthesized (SRS) F₂ generations were produced, respectively. In field trial in Bangladesh, the RS B. napus plants demonstrated variation in days to first flowering ranging from 29 to 73 days; some of which were similar to cultivated short duration B. napus, but not cultivated short duration B. rapa. The RS and SRS B. napus lines produced 2–4.6 and 1.6–3.7 times higher yields, respectively, as compared to cultivated short duration B. napus. Our developed RS lines may be useful for rapeseed breeding not only for subtropical regions, but also for areas such as Canada and Europe where spring rapeseed production can suffer from late spring frosts. Yield and earliness in RS lines are discussed.