Cocksfoot (Dactylis glomerata L.) seed production : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science at Massey University

Seed yield reduction due to variation in genotype, management, and incidence of diseases is common and well documented in grass seed crops. Two New Zealand cultivars (Grasslands Wana, Grasslands Kara) and two Japanese (Akimidori Makibamidori) cocksfoot cultivars from a three year old stand (sown in September 1991) at Grassland Aorangi Research Farm in the Manawatu were evaluated for their seed yielding capacity. In addition these cultivars were evaluated to determine the effectiveness of bactericide (Streptomycin), nematicide (Vydate/Oxamyl) or a combinations of bactericide and nematicide to determine their effect on seed yield with traditional Fungicide (Folicur) application being used as a control. The unit plot size was 1.2 X 3.0 m2, with each plot containing 4 rows. randomized block design with two factors (cultivar and pesticide) was utilized with 4 replications. In each cultivar pesticide were sprayed in four replicates from each block. The New Zealand cultivar Wana outyielded the other three cultivar and produced about 23%, 32%, and 70% higher pure seed/unit area than that cvs Kara, Makibamidori and Akimidori respectively. The ability of cv Wana to outyield other cultivar was largely due to its ability to produce a greater numbers of fertile tillers and higher number of florets/head. Seed yields in the New Zealand cultivar Kara and the Japanese cultivar Makibamidori were similar but significantly higher than cv Akimidori. The significantly higher seed yield of cv Kara was due largely to its significantly higher seed weight than the other cultivars. Similarly the higher seed yield in cv Makibamidori compared to Akimidori was mainly due to higher seed weight. The lower pure seed yield in cv Akimidori was apparently due to lack of proper photoperiodic effect or cold temperature during anthesis and its earlier seed developing resulted in more empty florets than the New Zealand cultivar and cv Makibamidori. Fertile tiller numbers spikelets/ head and florets/ head were significantly higher in cv Wana compared to the other 3 cultivars. However, the TSW was low. The TSW was highest in cv Kara. Highest recovery of pure seed was obtained from cv Wana in screen and blown fraction. Highest pure seed was obtained from cv Makibamidori in clean seed fractions. Foliar disease intensity in all the four cultivars was found to be similar at all 3 stages of plant growth although disease levels were generally low. Percentage purity in clean seed as well as in different cleaning fractions varied depending on cultivar but cv Akimidori was always ranked lowest. Seed germination percentage in single and in multiple florets was higher in cv Akimidori compared to the other 3 cultivars. Different cultivars reacted differently to the application of pesticide. Cultivar Wana produced the highest yield 103 g pure seed/m2 in the Fungicide (Folicur) treatment compared to 55, 38 and 22 g/m2 in cv. Kara, Makibamidori and Akimidori respectively. However all cultivars produced lower yields following the application of Streptomycin. Seed yield in cv Akimidori was not affected by any pesticide application. The lower yield in Streptomycin treatments was mainly due its phytotoxic effect on leaf tissue. Seed yield in Fungicide, Vydate and in V+S treated plots was similar but significantly better than in Streptomycin treated plots. Fertile tiller numbers were also similar in these treatments but spikelet and total floret numbers were higher in the V+S treatment than in the Fungicide treatment. TSW and florets/ spikelets was not affected by pesticide application. The recovery of pure seed was always lowest in the Streptomycin treatment in all fractions of machine cleaning of seed but was higher in V+S than Fungicide treatment, particularly in the machine clean fraction. However, the recovery of pure seed from the screen fraction did not vary significantly. Over all the foliar disease severity was low in Fungicide and V+S treatment and highest in Vydate treatment at maturity but no difference during vegetative growth or at peak flowering. The percent purity varied only in the air screen fraction but was high in the Vydate treatment. Seed germination was high in all pesticide treatments and being above 90% in term of single florets and 85% in multiple florets with minor improvement in V+S treatment both in single and multiple florets and in Fungicide treatment with multiple florets only. The second trial involved only one cultivar (cv Tekapo) and involved 4 plots from each block with 3 different types of fungicide Alto (cyproconazole), Bavistin (carbendazim), and Bravo (chlorothalonil) applied from flower initiation to harvest maturity at intervals of 14 to 21 day. No effect of fungicide occurred in seed yield or in yield components. Disease severity varied significantly only at harvest maturity and was lowest in Alto treated plots (2.75) compared to the control (4.25). However, no difference occurred in assessment at the vegetative stages or at peak flowering. No significant effect of fungicide was observed in terms of seed cleaning. The percentage purity was found higher in Alto and Bravo treated plots. Germination results were well above accepted levels (90%) in all fungicide treatments with Bavistin treatments being particularly useful

Influence of Bavistin, Cefotaxime, Kanamycin and Silver Thiosulphate on Plant Regeneration of Mentha piperita (L.) – An Important Multipurpose Medicinal Plant

Effect of different concentrations of bavistin, cefotaxime and kanamycin along wih the ethylene inhibitor STS were examined for in vitro plant regeneration using axillary bud explants of Mentha piperita. Filter sterilized bavistin, cefotaxime and kanamycin were added separately in the range of 0 – 300 mg (bavistin); 10, 20, 30, 40, 50, 100, or 120 µM/L (cefotaxime or kanamycin) to growth regulator free MS medium containing 3% sucrose. In a separate experiment bavistin (100 mg/l) along with growth regulators such as BAP and TDZ were added to MS medium containing 3% sucrose. Similarly the regeneration medium was supplemented with 10, 20, 30, 40, 50, 80, 100 or 120 µM/L of STS. Maximum number of shoots 6.85 ± 0.18 was seen with 150 mg/l bavistin with 100% regeneration. These plantlets were further maintained for root emergence on a rooting medium supplemented with growth regulators such as IAA, IBA and NAA. The rooted plants were acclimatized and transferred to field plots with 95% of plants surviving in the field

In vitro evaluation of different fungicides against Rhizoctonia solani and Alternaria citri infecting citrus

Rhizoctonia solani and Alternaria citri are major plant pathogens of citrus, causing considerable production losses. Chemical fungicides are widely used for disease control. Using the food poisoning technique under in vitro conditions, an experiment was undertaken to investigate the efficacy of several fungicides against those pathogens. To evaluate the effect on Rhizoctonia solani mycelial growth, five different chemicals, viz. SAAF (Carbendazim 12% WP + Mancozeb 63% WP), Bavistin (Carbendazim 50% WP), VACOMIL PLUS (Metalaxyl 15% WP + Copper oxychloride 35% WP), and Raze (Copper oxychloride 50% WP) were used at 100 ppm and 200 ppm concentration each. Similar chemicals were used for Alternaria citri except for additional Mancozab (Mancozeb 75% WP). Mycelial growth inhibition was measured until the fungus nearly covered the plate in control. All fungicides reduced the fungal growth compared to control. After 96 hours of incubation with Rhizoctonia solani, maximum inhibition (100%) was achieved at both concentrations of Bavistin, followed by SAAF @ 200 ppm (97.59%) and SAAF @ 100 ppm (88.25%), whereas VACOMIL PLUS and Raze had the minimum effect on the mycelial growth. Similarly, after 8 days of incubation of Alternaria citri, SAAF @ 200 ppm showed the highest inhibition (70.86%), followed by SAAF @ 100 ppm (65.11%), Mancozab @ 200 ppm (64.39%), and Mancozab @ 100 ppm (47.48%), but the effect of Bavistin, Raze, and VACOMIL PLUS had the lowest impact. The chemical proven effective against the pathogens should be trialed in pot and field experiments for further verification.&nbsp

In-vitro studies of some selected botanicals and baubiofungicide on mycelial growth and conidial germination of Cercospora arachidicola and Cercosporidium personatum

Efforts have been made to assess some plant extracts namely, Lycopersicon esculentum, Tagetus patula, Achras sapota, Azadirachta indica, Datura metel, Cymbopogon citrates, Polyalthia longifolia, Allium sativum and Allium cepa in vitro for the management of leaf spot (tikka) disease of groundnut cultivar Dhaka-1 caused by Cercospora arachidicola and Cercosporidium personatum. Results indicated that all the tested plant extracts and BAUBiofungicide suppressed the growth of mycelium and inhibition of conidial germination of C. arachidicola and C. personatum. Among the treatments, the leaf extracts of L. esculentum showed the most effective followed by leaf extract of D. metel, A. indica and BAU-Biofungicide in case of mycelial growth and conidial germination. Other plant extracts also had inhibitory effects. In case of conidial germination and germination inhibition, the least effective plant extract was C. citrates. Leaf extract of A. sapota was the least effective in case of mycelial growth. DOI: http://dx.doi.org/10.3329/ijarit.v3i2.17842 Int. J. Agril. Res. Innov. & Tech. 3 (2): 36-40, December, 201

Control of Phomopsis Blight of Egg Plant through Fertilizer and Fungicide Management

The experiments were conducted at Laboratory of the Department of Plant Pathology and in the farm of Sher-e-Bangla Agricultural University, Dhaka-1207, Bangladesh during Rabi season of the year 2007-2008. Four fungicides viz. Bavistin 50 WP (Carbendazim), Tilt 250 EC (Propiconazole), Cupravit 50 WP (Copperoxychloride) and Dithane M-45 (Mancozeb) and micronutrients (Gypsum, ZnO and Boric acid) were evaluated against Phomopsis vexans causing Phomopsis blight and fruit rot of eggplant. The fungicides and micronutrients either applied individually or in combination showed significant effect in terms of per cent leaf infection, fruit infection, leaf area diseased and fruit area diseased in comparison to control. Effect of each fungicide applied in combination with micronutrients always showed better performance in reducing disease incidence and disease severity than the fungicides applied alone. Among the fungicides, Bavistin 50 WP (0.1%) proved to be effective arresting the spore germination and mycelia growth of Phomopsis vexans assayed in in vitro test. Reduction of leaf area diseased caused by Bavistin 50 WP (0.1%) in combination with micronutrients were 58.17, 67.37, 78.41 and 85.25%, respectively at preflowering, post-flowering, fruiting and fruit ripening stages while Bavistin 50 WP (0.1%) alone reduced by 52.22, 58.67, 74.19 and 83.09%, respectively at those stages. Similarly reduction of fruit area diseased caused by Bavistin 50 WP (0.1%) in combination with micronutrients were 57.93 and 79.79%, respectively at fruiting and fruit ripening stages while Bavistin 50WP (0.1%) alone reduced by 56.93 and 76.14%, respectively at those stages. Micronutrients had little effect against the disease but significantly better than control.Int. J. Agril. Res. Innov. & Tech. 3 (1): 66-72, June, 2013 DOI: http://dx.doi.org/10.3329/ijarit.v3i1.1609

Effect of Bavistin and Silver Thiosulphate on In Vitro Plant Regeneration of Stevia rebaudiana

Effect of Bavastin (fungicide), Silver thiosulphate (Ehtylene inhibitor) on shoot regeneration using axillary bud explants of Stevia rebaudiana was studied.  In Bavastin supplemented medium multiple shoots were induced from axillary bud explants.  Bavistin in combination with BA induced maximum number of shoots (6.4±0.2).  Ethylene inhibitor silver thiosulphate also favoured the shoot morphogenesis. At lower concentration of silver thiosulphate (10-40 mM/L) maximum number of shoots (2.1-3.2) were obtained. All the in vitro raised shoots with a length of 3-5 cm were transferred to rooting medium.  The best rooting response was observed on 2.0mg/L IBA. The well rooted plantlets were transferred to polybags containing soil + vermiculite in 1: 1 ratio for hardening. Finally the hardened plantlets were transferred to field conditions for maximum survivability

Assessment of Invitro Propagation and Conservation of Swertia Chirayata

A protocol for in vitro propagation and conservation was developed for Swertia chirayita, an endangered medicinal plant. The sterilized explants (leaves) cultured on MS medium supplemented with 0.1 mg/l NAA and 3.0 mg/l BA gave best results for in vitro callus induction. Shoot regeneration was obtained from the callus on the same medium. The in vitro shoots cultured on MS medium supplemented with 2.5 mg/l BA and 0.1 mg/l Kinetin gave best results for in vitro shoot multiplication. The MS medium supplemented with 0.1 mg/l NAA and 3.0 mg/l BA medium was found to be the best for direct shoot regeneration from in vitro leaves. 80.30% root induction from in vitro grown shoots was obtained on half strength MS medium supplemented with 400 mg/l activated charcoal and 0.1 mg/l NAA. In vitro conservation was carried out by using two different approaches namely slow growth by changing media composition (sucrose and abscisic acid), at low temperature and cryopreservation following vitrification.With increase in concentration of sucrose and ABA decrease in growth of in vitro shoots was observed. No shoot multiplication with average leaf size of 0.35 cm and shoot length 0.67 cm was observed on half MS containing 90 g/l sucrose. Similarily, in case of media containing half strength MS salts and 3.0 mg/l ABA showed no shoot multiplication,0.83 cm average leaf size and 0.83 cm shoot length. At low temperature the in vitro shoots incubated at 4o C, showed 100% retrieval, with 1.00 cm average number of shoots, 0.86 cm shoot length and 0.34 cm leaf size. In vitro shoots incubated at 10o C, showed 100% retrieval, with 1.00 cm average number of shoots, 0.76 cm shoot length and 0.23 cm leaf size. During studies the vitrified shoot gave retrieval of 42.33% when precooled at 4o C while only 22.37% vitrified shoots were retrieved from those precooled at 10o C

In vitro evaluation of biocontrol agents and fungicides on wood decay fungiganoderma associated with mortality of tree legumes

An experiment was conducted to isolate a number of biocontrol agent- Trichoderma spp. from infected spawn packets of oyster mushroom at National Mushroom Development and Extension Centre, Savar, Dhaka, Bangladesh. These bio-control agents were used as antagonist against four wild wood decay fungi of Ganoderma, viz., G. lucidum-1, G. lucidum-2, G. lucidum-3, G. applanatum and two cultivated G. lucidum-4, G.lucidum-6 under in vitro condition. An in vitro trial of Trichoderma spp. against Ganoderma were performed by dual culture, by treating with volatile, non-volatile and naturally untreated metabolites of bio-control agents. In dual culture, all the Trichoderma species showed 70- 100% mycelia inhibition of G. lucidum-1 and G. lucidum-2, 55.6-100% inhibition of G. lucidum-3, 20-66.7% of G. applanatum, 100% of G. lucidum-5, 75-100% of G. lucidum-6. Effects of heat killed extracts of Trichoderma spp. on growth of G. lucidum-2 (wild) and G. lucidum-6 (cultivated) were also evaluated. Fungicides Bavistin and Dithane M-45 were also used to investigate the mycelial growth inhibition of Ganoderma spp.Int. J. Agril. Res. Innov. & Tech. 6 (2): 31-35, December, 201