http://103.7.193.12:8080/xmlui/handle/123456789/139 Fri, 17 Apr 2026 15:35:09 GMT 2026-04-17T15:35:09Z http://103.7.193.12:8080/xmlui/handle/123456789/808 Antimicrobial Activities of Cover Crops against Rhizobium vitis, the Grapevine Crown Gall Pathogen Islam, Md. Tariqul The aim of this research was to evaluate the antimicrobial activity of chinese milk vetch (Astragalus sinicus), forage rape (Brassica napus), orchard grass (Dactylis glomerata), ryegrass (Lolium perenne), italian ryegrass (Lolium multiflorum) and hairy vetch (Vicia villosa), and then to isolate and characterize the bioactive compounds from the most active cover crop species. And also to enhance existing and induced defense responses in “Campbell Early’ and ‘Kyoho’ grapevine using tested cover crops extracts. Crude extracts from the shoot and root tissue of chinese milk vetch (Astragalus sinicus), forage rape (Brassica napus), orchard grass (Dactylis glomerata), ryegrass (Lolium perenne), italian ryegrass (Lolium multiflorum) and hairy vetch (Vicia villosa) were investigated for their antimicrobial activity against Rhizobium vitis, Bacillus subtilis, Aspergillus niger, Botrytis cinerea, Colletotrichum gloeosporioides, C. acutatum, and Elsinoe ampelina. Extracts were prepared from dried and powdered shoots and roots using common solvents (methanol, ethyl acetate, and water) with different degrees of polarity. The diameter of inhibition zones of the shoot (2,000 pg/disc) and root (2,500 ug/disc) extracts in water and ethyl acetate solvents against R. vitis and B. subtilis were found to be in the range of 9.8 1.3 to 18.0 + 2.0 mm and 9.0 + 0.7 to 16.4 + 0.5 mm, respectively. However, methanolic extract did not show any inhibitory activity. All the extracts against A. niger showed a minute inhibition zone which was not measurable, whereas the other tested fungi were not inhibited by the extracts. The minimum inhibitory concentration values of shoot and root extracts against the tested bacteria were found to be in the range of 3.12 to 12.5 and 3.12 to 25 mgmL”, respectively. A preliminary phytochemical screening of all the tested extracts indicated the presence of alkaloids, flavonoids, saponins, cardiac glycosides, steroids and terpenoids. Total polyphenol contents of extracts positively correlated with their inhibitory activities, suggesting their potential antibacterial efficacy. Three antibacterial compounds isolated from hairy vetch (Vicia villosa Roth) shoots against grapevine crown gall pathogen. The hairy vetch shoot powder was sequentially extracted and screened for antibacterial activity by the disc diffusion method. Ethyl acetate extract from the hairy vetch shoots was subjected to column chromatography on silica gel. The structures of the compounds were then elucidated by spectroscopic analysis and chromatographic assay. Three compounds were isolated and identified as bis (2-ethylhexyl) phthalate (compound 1), diethyl phthalate (compound 2), and p-hydroxybenzoic acid (compound 3). The compounds showed potential antibacterial effect as diameters of inhibition zones (7.3 + 0.3 to 11.2 + 0.4 mm) against Rhizobium vitis and Bacillus subtilis. The minimum inhibitory and minimum bactericidal concentrations of these compounds against the target bacteria were found to range from 62.5 to 125 and 125 to 250 pg-mL”", respectively. The compounds also showed bactericidal activity based on the viable counts of the tested strain. These findings indicate that isolated compounds could be used as possible candidates for control of crown gall disease in grapevines caused by R. vitis. Water based crude extracts from hairy vetch (Vicia villosa) and ryegrass (Lolium perenne) were investigated for their antimicrobial activity against Rhizobium vitis, the causal agent of crown gall of grapevine (Vitis spp.) grown in the greenhouse. One hundred ml of each extract (500, 1,000 and 2,000 g/4 L) from hairy vetch and ryegrass prepared from fresh and pounded shoots and roots were applied by water irrigation. The shoot and root extracts displayed remarkable in vivo antibacterial effects on reduction of gall formation by R. vitis by up to 24.97 to 75.02% in ‘Kyoho’ (susceptible) and 100% in ‘Campbell Early’(moderately resistant to crown gall) grapevines compared with the untreated control. The expression of several defense-related genes was investigated by quantitative real-time and semi-quantitative RT-PCR in two grapevine cultivars. The treatment of an extract from hairy vetch and ryegrass showed the induction of defense response-related genes in both cultivars of grapevines. Treatment of tested plant extracts exhibited differential induction of the accumulation of defense related genes including B-1,3-glucanase (PR-2), phenylalanine ammonia-lyase (PAL), thaumatin-like protein (ZZP), leucine reach-repeat (LRR), polygalacturonase inhibiting protein (PG/P), stilbene synthase (StSy) and catalase (CAT). Expression analysis of defense related genes revealed noticeable differences between ‘Kyoho’ and ‘Campbell Early’ grapevines. Based on the reduction of crown gall and induction of defense-related genes by hairy vetch and ryegrass extracts, extracts from tested cover crops can act as efficient biological inducers in an alternative strategy of grapevine crown gall protection. Stilbenes are natural compounds occurring in a number of plant families, including Vitis vinifera L., which is the most important species grown worldwide for grape and wine x1 production. Extract of hairy vetch and ryegrass showed induction of stilbene synthase gene in the grapevine leaves in previous study. The present study investigated the change of stilbene compounds (trans-and cis- resveratrol and piceides, and piceatannol) and induction of gene expression related with their synthesis by treatment of extracts from hairy vetch and ryegrass in the berries of ‘Campbell Early’ and ‘Kyoho’ grapes. Trans-resveratrol was present in substantial amounts (4.1 to 5.3 g/g FW) in ‘Campbell Early’ and (7.6 to 10.4 g/g FW) in ‘Kyoho’, whereas trace amounts of cis- resveratrol were detected in the range of 0.8 to 1.0 ug/g FW in treated grape berries. Besides, the concentration of piceid and piceatannol in berries of both cultivars was markedly enhanced in response to treatment of hairy vetch and ryegrass extracts. Accumulation of stilbene compounds in grape berries increased in response to tested extract, 24 h after treatment. Berries treated with extracts showed the increase in transcript levels of genes coding enzymes involved in stilbene compound biosynthesis (phenylalanine ammonia lyase, chalcone synthase and stilbene synthase). Changes in stilbene compounds content were correlated with levels of StSy mRNA, indicating a transcriptional control of stilbene synthase activity. The results suggest that stilbene compounds were accumulated by hairy vetch/ryegrass extracts through the induction of StSy transcription in grape berries The results of our study demonstrate that the secondary metabolites (crude extract and purified bioactive molecules) derived from tested cover crop species possessed a broad spectrum of biological activities, and act as an efficient biological induces in an alternative strategy of grapevine crown gall protection. Grapevine (Vitis spp.), one of the most widely grown fruit crops in the world, is subject to a number of bacterial, fungal, and viral diseases (Wang et al., 2011), which result in significant reductions in crop yields (Montesinos, 2007). Grapevine crown gall one of the major bacterial disease caused by Rhizobium vitis (Ophel and Kerr, 1990) mainly occurs during early summer in Korea (Chung and Shim, 1996; Park et al., 2000) and causes severe economic loss by inducing significantly inferior growth and reduced fruit productivity (Burr et al., 1998; Schroth et al., 1988). The bacterial pathogen, Rhizobium vitis, which colonizes the xylem vessels of the vines, may persist in a latent condition for many years before symptoms develop (Burr and Katz, 1984; Tarbah and Goodman, 1986; Goodman et al., 1987). The disease is spread to new plants primarily by vegetative propagation, but it may also enter the plants through infested soil. Freeze damage or wounds caused by mechanical injury provide sites for infection and the development of galls, or tumor-like growths. These tumors usually girdle the trunk, preventing the flow of nutrients and thus reducing vine vigor. Galled vines frequently produce inferior shoot growth, and portions of the vine above the galls may die. Galled vines are more susceptible to adverse environmental conditions, such as water stress and winter injury. Sat, 01 Jun 2013 00:00:00 GMT http://103.7.193.12:8080/xmlui/handle/123456789/808 2013-06-01T00:00:00Z http://103.7.193.12:8080/xmlui/handle/123456789/142 EFFECTS OF MANURE, TILLAGE AND MULCH ON THE GROWTH, YIELD AND QUALITY OF GARLIC (Allium sativum L.) KABIR, MOHAMMAD AHSANUL Nine experiments were conducted in the field laboratory, USDA-Alliums’ project, Bangladesh Agricultural University, Mymensingh during rabi seasons of 2006-2009 with the main objective of determining the effect of manure, tillage and mulch on the growth, yield and quality of garlic. The manure experiment revealed that the plant height; number of leaves per plant; length and breadth of the longest leaf; fresh and dry weights of leaves, bulb & roots; breadth of bulb, total number of cloves and yield per plot were markedly influenced by the treatments. Among the different levels of organic manure, the highest dose of mustard oil cake (5 t/ha) was the best to influence the yield and yield contributing traits followed by the highest dose of cowdung (25 t/ha). The experiment under zero tillage condition further demonstrated that organic manure had remarkable influence on almost all the parameters observed. The tallest plant, maximum number of leaves, highest breadth and length of the longest leaves were recorded from the treatment of mustard oil cake. But on the basis of economic analysis, maximum net return and BCR (2.59) were recorded with cowdung. Plants grown with mulch showed better performance in most of the yield contributing attributes, and ultimately produced higher yield than the nonmulched plants. Again, plants grown with 10 cm thickness of water hyacinth mulch gave better results in most of the cases. The treatment combination of zero tillage with 10 cm thick mulch produced the highest yield (9.92 t/ha). Moreover, zero tillage showed the highest storage quality because it resulted in the lowest weight loss (8.45%), insect infested bulbs (6.67%) as well as rotten bulbs (2.44%) even after 150 days of storage. In contrast, conventional tillage with no mulch and 6 cm thick mulch were found to have lower storage quality compared to the other treatment combinations. Two experiments were also conducted to study the effects of green manuring and organic sources of nutrients on the growth and yield of garlic. One experiment consisted of three green manuring (GM) species, namely Seshania rostrata, S. aculeata and Phaseolus mungo, and 6 organic manures viz. cowdung, compost, mustard oil cake, rotten water hyacinth and bone meal. The growth of the garlic was higher when it was cultivated with the residual effect of S. rostrata compared to seasonal fallow land (control). On the other hand, in another experiment P. mungo was found to have superior effect in terms of yield and yield contributing characters of garlic when this GM was incorporated with organic manure. Garlic grown under zero tillage showed remarkable variation in terms of percent emergence. However. differences were not significant between rice straw and water hyacinth mulch. It was also noticed that both the tillage conditions as well as mulches exerted profound effects on the yield and yield contributing parameters. Puddling and zero tillage practices resulted in higher yield compared to the conventional tillage. The treatment having organic and inorganic fertilizers (50% of the recommended dose of inorganic fertilizers + 2 ton of mustard oil cake/ha) produced the highest yield (11.5 t/ha) followed by 50% of the recommended dose of inorganic fertilizers + 15 ton cowdung/ha and the treatment control showed poor performance (6.2 t/ha). Integrated approach of organic farming (Green manure + organic manure + mulch) had the most pronounced effect compared to the control or inorganic fertilizers. Garlic (Allium sativum L.), a herbaceous perennial species belonging to the family Alliaceae (Kurian, 1995), is one of the vital bulbous spices. This aromatic spice is cultivated as an annual crop and the second most widely used A//ium after onion (Bose and Som, 1990). It is popular all over the world as a valuable spice for different dishes. Garlic plays remarkable dietary and medicinal roles throughout the history of mankind. In some western countries, the sale of garlic preparations ranks with those of leading prescribed drugs. The aqueous extract of garlic cloves (containing allicin and related disulphides) reduces cholesterol] level in humans (Augusti, 1977). Garlic also helps eliminating waste materials and dangerous free radicals from the human body. According to the Unani and Ayurvedic medicines, in the treatments of diseases like chronic infection of stomach and intestine, dysentery, typhoid, cholera and diseases of lungs garlic is successfully used (Chopra er al., 1958). Recently, oil and powder are prepared from it for adding flavour to varied curries (Pruthi, 2006). Besides, it is used in preparing chutneys, pickles, ketchup etc. Fri, 01 Oct 2010 00:00:00 GMT http://103.7.193.12:8080/xmlui/handle/123456789/142 2010-10-01T00:00:00Z http://103.7.193.12:8080/xmlui/handle/123456789/140 DEVELOPMENT OF PACKAGE TECHNOLOGY FOR GINGER PRODUCTION IN BANGLADESH ISLAM, MD: ASHIKUL The present research work was conducted at the Spices Research Centre, Bangladesh Agricultural Research Institute, Shibgonj, Bogra during the period 2008-09 to 2010- 2011 to develop technology package for higher ginger production. Series of experiments were conducted in relation to rhizome size, plant spacing, planting time, mulching, irrigation, planting method, nitrogen and potassium fertilizer application and rhizome rot control for ginger production. Results revealed that 50g rhizome gave highest yield but the economic size was 40g for ginger production. The maximum yield was obtained from the high plant density. It gave the highest rhizome yield by increasing plant population per unit area, and lower density (50 x 25cm) reduced rhizome yield per unit area due to less plant population. But from the economic point of view, 40 x 25cm spacing was the significantly best for ginger production. In case of planting time 1" April planting the was best for ginger production. Rice straw mulch with two irrigations was the best for ginger production. Ridge method was found suitable for ginger cultivation than the flat planting method. In case of fertilizer, nitrogen applied at 120 and potassium at 120kg ha™' were observed to be the optimum for obtaining higher ginger yield. Neem cake at a rate of 2 t ha! was better to control rhizome rot and ginger production. Based on the results of the experiments, a technology of package for ginger production has been suggested. The suggested technology package includes: 40g seed rhizome, 40 x 25cm spacing, 1* April planting, rice straw mulch, two irrigation, ridge planting method, nitrogen application at 120kg and potassium 120kg ha™' and neem cake at 2 t ha! for growing ginger under Bogra, Banglabesh condition. Ginger (Zingiber officinale Rosc.), belonging to the family Zingiberaceae, is one of the most vital spices and cash crop in Bangladesh. It is a perennial herb having underground rhizomes but it is grown as an annual crop. It is a tropical crop believed to be originated in the South-East Asia (Singh and Singh, 2000). It is a plant of very ancient cultivation and has long been used in Asia. It is one of the earliest oriental spices known to Europe and is still in large demand there (Purseglove et al., 1981). Mon, 01 Jul 2013 00:00:00 GMT http://103.7.193.12:8080/xmlui/handle/123456789/140 2013-07-01T00:00:00Z