Effect of Organic and Inorganic Fertilizers on Soil Properties and the Growth, Yield and Quality of Tomato in Mymensingh, Bangladesh

Field trials were conducted on tomato for yield and quality of fruits using different types of organic and inorganic fertilizers at the horticulture farm of Bangladesh Agricultural University (BAU), Mymensingh. Fertilizer treatments were tested on two varieties of tomato ca. Roma VF and BARI 15. The fertilization treatments were T1, vermicompost (12 t/ha); T2, compost (10 t/ha); T3, integrated plant nutrient system (IPNS) or mixed fertilizers (organic 2/3 part and inorganic 1/3 part); T4, inorganic fertilizers; and a control (T5). Results showed growth and yield (20.8 t/ha) in tomato were higher in the IPNS treatment. A higher number of fruits per plant (73.7) and plant height (73.5 cm) were obtained from mixed fertilizers (organic 2/3 + inorganic 1/3) or IPNS (integrated plant nutrient system) in Roma VF than other treatments. Fruit yield and diameter were found statistically significant. No significant difference was observed in the quality (total soluble solids) of tomato fruits in both varieties’ response to the treatments. The electrical conductivity and pH of the soil were improved by the application of organic manure

Effect of Organic, Inorganic Fertilizers and Plant Spacing on the Growth and Yield of Cabbage

The impact of chemical farming and the negative consequences on the environment and human health in Bangladesh are on the rise. Organic farming is gaining attention and increasing globally because it is eco-friendly, safe and has benefits for human health. A field study was conducted at the horticulture farm of Bangladesh Agricultural University (BAU), Mymensingh, to evaluate the growth and yield performance of cabbage cv. Atlas—70 using organic and inorganic fertilizers in various plant spacing arrangements. Two factor experiments were conducted on plant spacings of 60 cm × 40 cm (S1), 60 cm × 50 cm (S2) and 60 cm × 60 cm (S3) and fertilizers vermicompost (T1), biogen (T2), integrated plant nutrient system (IPNS) Organic (⅔) + inorganic (⅓) (T3) and inorganic (T4). IPNS (T3) application increased the marketable yield (54.77 t·ha−1) of cabbage. The highest marketable yield (48.75 t·ha−1) was obtained with a plant spacing of 60 cm × 40 cm (S1). No significant variation was found in plant spacings S1 and S2. The treatment combination of S2T3 recorded the highest plant height (37.81 cm), plant spread (47.75 cm), cabbage head (21.80 cm), stem length (12.31 cm), thickness of the cabbage head (12.53 cm) and marketable yield (65.0 t·ha−1). The results suggest that IPNS (T3) combining organic and inorganic fertilizer applications with a 60 cm × 50 cm spacing (S2T3) increases the yield performance of cabbage

Genetic and Epigenetic Regulation of Vernalization in Brassicaceae

A wide variation of morphological traits exists in Brassica rapa L. and Brassica oleracea L., and cultivated vegetable varieties of these species are consumed worldwide. Flowering time is an important agronomic trait in these species and varies among varieties or cultivars. Especially, leafy vegetable species need a high bolting resistance. Isolation of FLOWERING LOCUS C (FLC), one of the key genes involved in vernalization, has now provided an insight into the molecular mechanism involved in the regulation of flowering time, including the role of histone modification. In the model plant Arabidopsis thaliana, FLC plays an important role in modulating flowering time. The response to vernalization causes an increase in histone H3 lysine 27 tri-methylation (H3K27me3) that leads to reduced expression of the FLC gene. B. rapa and B. oleracea both contain several paralogs of FLC at syntenic regions identified as major flowering time and vernalization response quantitative trait loci (QTL). We introduce the recent research, not only in A. thaliana, but also in the genus Brassica from a genetic and epigenetic view point

Breeding for Disease Resistance in Brassica Vegetables Using DNA Marker Selection

The Brassica genus comprises of agro-economically important vegetables. Disease causes great yield loss of Brassica vegetables worldwide. Different traditional methods such as crop rotation and chemical control have limited effect on different diseases of Brassica vegetables and cannot completely eradicate the pathogens by these methods. Development of disease resistant cultivars is one of the most effective, ecofriendly, and cheapest measure to control Brassica diseases. With the development of genomics, molecular biology techniques, and biological methods, it is possible to discover and introduce resistance (R) genes to efficiently control the plant diseases caused by pathogens. Some R genes of major diseases such as Fusarium wilt and clubroot in Brassica vegetables have been already identified. Therefore, we will focus to review the Fusarium wilt and clubroot resistance in Brassica vegetables and the methodologies for identification, mapping, and pyramiding of R genes/quantitative trait loci (QTLs) to develop disease resistant cultivars. These techniques will be helpful for sustainable crop production and to maintain global food security and contribute to ensure protection of food supply in the Asian country as well as throughout the world

Resistance and co-resistance of metallo-beta-lactamase genes in diarrheal and urinary tract pathogens in Bangladesh

Carbapenem antibiotics are the drug of choice for treating multidrug-resistant bacterial infections. Metallo-beta-lactamases (MBLs) are carbapenemase capable of hydrolyzing nearly all therapeutically available beta-lactam antibiotics. Consequently, a need to assess the frequency and phenotypic resistance phenomena of two MBL genes in diarrheal and urinary tract infections (UTIs). Samples were collected through a cross-sectional study, with MBLs genes detected via PCR. Two hundred twenty eight diarrheal bacteria were isolated from 240 samples. The most predominant pathogens were Escherichia coli (32%) and Klebsiella spp. (7%). Phenotypic resistance to amoxicillin-clavulanic acid, aztreonam, cefuroxime, cefixime, cefepime, imipenem, meropenem, gentamicin, netilmicin, and amikacin was 50.4%, 65.6%, 66.8%, 80.5%, 54.4%, 41.6%, 25.7%, 41.2%, 37.2%, and 42.9%, respectively. Total 142 UTI pathogens were obtained from 150 urine samples, with Klebsiella spp. (39%) and Escherichia coli (24%) are the major pathogens. Phenotypic resistance to amoxycillin-clavulanic acid, aztreonam, cefuroxime, cefixime, cefepime, imipenem, meropenem, gentamicin, netilmicin, and amikacin was 93.7%, 75.0%, 91.5%, 93.7%, 88.0%, 72.5%, 13.6%, 44.4%, 71.1%, and 43%, respectively. Twenty four diarrheal isolates carried either blaNDM-1 or blaVIM genes; the overall MBL gene prevalence was 10.5%. Thirty six UTI pathogens carried either blaNDM-1 or blaVIM genes (25.4%). Seven isolates carried both blaNDM-1 and blaVIM genes. MBL genes exhibited a strong association with phenotypic carbapenem and other beta-lactam antibiotic resistance. Resistance to carbapenems requires active surveillance and stewardship

Long noncoding RNAs in Brassica rapa L. following vernalization

© 2019, The Author(s). Brassica rapa L. is an important agricultural crop that requires a period of prolonged cold for flowering. This process is known as vernalization. Studies have shown that long noncoding RNAs (lncRNAs) play important roles in abiotic stress responses and several cold-responsive noncoding RNAs have been suggested to be involved in vernalization. We examined the transcriptome of the Chinese cabbage inbred line (B. rapa L. var. pekinensis) RJKB-T24, and identified 1,444 long intergenic noncoding RNAs (lincRNAs), 551 natural antisense transcripts (NATs), and 93 intronic noncoding RNAs (incRNAs); 549 of the 2,088 lncRNAs significantly altered their expression in response to four weeks of cold treatment. Most differentially expressed lncRNAs did not lead to a change of expression levels in mRNAs covering or near lncRNAs, suggesting that the transcriptional responses to four weeks of cold treatment in lncRNA and mRNA are independent. However, some differentially expressed mRNAs had NATs with expression altered in the same direction. These genes were categorized as having an abiotic stress response, suggesting that the paired-expression may play a role in the transcriptional response to vernalization or cold treatment. We also identified short-term cold treatment induced NATs in BrFLC and BrMAF genes, which are involved in vernalization. The lncRNAs we identified differed from those reported in Arabidopsis thaliana, suggesting the role of lncRNAs in vernalization differ between these two species

The histone modification H3 lysine 27 tri-methylation has conserved gene regulatory roles in the triplicated genome of Brassica rapa L

© The Author(s) 2019. Published by Oxford University Press on behalf of Kazusa DNA Research Institute. Brassica rapa L. is an important vegetable and oilseed crop. We investigated the distribution of the histone mark tri-methylation of H3K27 (H3K27me3) in B. rapa and its role in the control of gene expression at two stages of development (2-day cotyledons and 14-day leaves) and among paralogs in the triplicated genome. H3K27me3 has a similar distribution in two inbred lines, while there was variation of H3K27me3 sites between tissues. Sites that are specific to 2-day cotyledons have increased transcriptional activity, and low levels of H3K27me3 in the gene body region. In 14-day leaves, levels of H3K27me3 were associated with decreased gene expression. In the triplicated genome, H3K27me3 is associated with paralogs that have tissue-specific expression. Even though B. rapa and Arabidopsis thaliana are not closely related within the Brassicaceae, there is conservation of H3K27me3-marked sites in the two species. Both B. rapa and A. thaliana require vernalization for floral initiation with FLC being the major controlling locus. In all four BrFLC paralogs, low-temperature treatment increases H3K27me3 at the proximal nucleation site reducing BrFLC expression. Following return to normal temperature growth conditions, H3K27me3 spreads along all four BrFLC paralogs providing stable repression of the gene

The role of FRIGIDA and FLOWERING LOCUS C genes in flowering time of Brassica rapa leafy vegetables

© 2019, The Author(s). There is a wide variation of flowering time among lines of Brassica rapa L. Most B. rapa leafy (Chinese cabbage etc.) or root (turnip) vegetables require prolonged cold exposure for flowering, known as vernalization. Premature bolting caused by low temperature leads to a reduction in the yield/quality of these B. rapa vegetables. Therefore, high bolting resistance is an important breeding trait, and understanding the molecular mechanism of vernalization is necessary to achieve this goal. In this study, we demonstrated that BrFRIb functions as an activator of BrFLC in B. rapa. We showed a positive correlation between the steady state expression levels of the sum of the BrFLC paralogs and the days to flowering after four weeks of cold treatment, suggesting that this is an indicator of the vernalization requirement. We indicate that BrFLCs are repressed by the accumulation of H3K27me3 and that the spreading of H3K27me3 promotes stable FLC repression. However, there was no clear relationship between the level of H3K27me3 in the BrFLC and the vernalization requirement. We also showed that if there was a high vernalization requirement, the rate of repression of BrFLC1 expression following prolonged cold treatments was lower

Essays on the Macroeconomic Impact of Monetary Policy, Fiscal Policy and Financial Development: An Empirical Investigation

This thesis includes three self-contained chapters using applied macroeconomics and focusing on the impact of monetary policy, fiscal policy and financial development on real economy in varied context. The first chapter investigates the monetary policy transmission mechanism and the extent to which exchange rate and oil price shocks exert pressure on macroeconomic variables in Bangladesh. Using a Vector Error Correction model, we find that monetary policy shocks have significant impact on inflation but not on output, while both interest rate and exchange rate channels play active roles in the determination of all other macroeconomic variables. Moreover, external shocks such as oil price and exchange rate shock are also important factors that influence domestic macroeconomic variables in Bangladesh. The second chapter examines the macroeconomic impact of fiscal policy in Euro-area countries under the same Monetary Union: Austria, Belgium, Finland, France, Germany, Ireland, Luxembourg, Netherlands, Portugal, Spain. Using structural VAR model framework, we show that a positive government spending shock has expansionary macroeconomic effects in Finland and France, a contractionary effect in Austria, Belgium, Germany, Netherlands, Portugal and Spain, but no significant effect is observed in Ireland and Luxembourg. Furthermore, a positive tax shock has a permanent recessionary effect in Belgium, Finland, France and Germany; a non-Keynesian effect in Luxembourg, Ireland, Netherlands and Portugal and almost unresponsive in Spain and Austria. Moreover, the estimated fiscal multipliers range between 0 to 1 on impact and negative for high debt countries. The signs of these multipliers also show a divide between countries, demonstrating both a Keynesian and non-Keynesian nature fiscal policy across these Monetary Union countries. The third chapter examines the nexus between financial development and economic growth in five countries: Australia, China, South Africa, the UK and the US. We find that in Australia and the US, only market-based financial intermediaries have significant long-run impacts on economic growth, while in China, South Africa and the UK both bank-based and market-based financial indicators have long-run impacts on economic growth. Moreover, in Australia and USA, the financial shock impact the economic growth through stock market only, whereas in South Africa its impact is through banks. However, in China and UK both the banks and stock market play an active role to transmit the shock of financial sector to real economy. Furthermore, we find that economic growth leads to both bank based and market based financial development in Australia, China and South Africa whereas it only leads to market based financial development in UK and USA.Thesis (Ph.D.) -- University of Adelaide, School of Economics and Public Policy, 202