Growth of white clover seedlings treated with aqueous extracts of leaf and root of tough lovegrass (original) (raw)
Related papers
1992
The effects of chemical manipulation through the use of plant growth regulators on white clover (Trifolium repens L.) cv. Grasslands Pitau grown for seed were investigated in this study, using both sward and individual plant trials. A white clover seed crop was established in autumn 1988, certified breeders seed of cv. Grasslands Pitau being sown at 3 kg/ha in 45 cm rows. Three plant growth regulators, chlormequat chloride (1.5 and 3.0 kg a.i./ha), paclobutrazol (0.5 and 1.0 kg a.i./ha) and triapenthenol (0.5 and 1.0 kg a.i./ha) were applied at two growth stages; during reproductive initiation (11 October) or at the appearance of the first visible bud (8 November). A fu rther plant growth regulator, daminozide (2.0 and 4.0 kg a.i./ha) was applied only in November. Chlormequat chloride, daminozide and triapenthenol did not significantly affect node production, inflorescence production or seed yield, although thousand seed weight (TS W) was reduced. Paclobutrazol significantly reduced petiole length and increased the number of nodes/m 2 , but did not affect dry matter production. The October application of paclobutrazol at 1.0 kg a.i./ha significantly increased potential harvestable seed yield by 71 % through increasing the number of inflorescences produced, but the 57 % increase following the November application at the same rate did not differ significantly fr om the control. Actual seed yield differences (+ 25 and 26 %) were also not significant. In the following season (1989/1990), three of the plant growth regulators (chlormequat chloride at 3.0 kg a.i./ha, paclobutrazol at 1.0 kg a.i./ha, triapenthenol at 1.0 kg a.i./ha) were applied using the same site as for the 1988/1989 trial (i.e. a second year crop), but avoiding plots previously sprayed with paclobutrazol to e. liminate possible soil residual effects. Applications were either during early reproductive initiation (September), during peak reproductive initiation (October) or when reproductive buds/early flowers were first visible (November). Chlormequat chloride did not affect either vegetative or reproductive growth and development. Triapenthenol initially retarded growth (e.g. by reducing petiole length), but this effect was only transiatory, and was no longer evident 3 weeks after application. Although triapenthenol applied in November increased inflorescence number at peak flowering, seed yield was not increased. Triapenthenol applied in October did not affect inflorescence number at peak flowering, but reduced TS W. Paclobutrazol applied in September, October and November reduced petiole length and leaf size, V My Indonesian friends, especially Supanjani, Kusmintarjo, Mohammad Chozin and Hari Eko Irianto for their help in the fi eld work. All postgraduate students in the Seed Technology Centre for their friendship and for making my stay in New Zealand pleasant. The New Zealand Ministry of External Relation and Trade for financing my study and living in New Zealand. Massey University for awarding me the Helen E. Akers Scholarship. The Ministry of Agriculture of the Republic of Indonesia for giving me an opportunity to study in New Zealand. Finally, I would like to express my gratitude to my parents for their love, understanding and encouragement, and to Eileen Shee-Mei for her support, understanding, help and more importantly, for being by my side. To them, I dedicate this thesis.
Effect of pretreatments on seed germination rate of red clover (Trifolium pratense L.) populations
African Journal of Agricultural Research, 2011
The aim of the present study was to investigate effective methods in breaking the seed dormancy for red clover populations collected from Central-Black Sea Region of Turkey. To increase germination percentage of red clover, precooling, preheating, hot water, potassium nitrate and mechanical scarification were used. The results pointed out that there was a significant difference among the populations and treatments regarding germination rates. While average germination vigor of seeds was 29.4% in control treatments, it increased to 54.2% in mechanical scarification. Additionally preheating and precooling treatments were recommended.
Expression of seed vigor and initial growth of red clover under fungicide influence
COLLOQUIUM AGRARIAE
The objective of this study was to evaluate the expression of seeds vigor and physiological performance of initial growth of red clover plants under the influence of fungicide doses of carboxin + thiram. Three lots of seeds were used (high; medium and low vigor) treated with 0; 150; 250 fungicide doses and 350 mL i.a./100 kg of seeds. Germination, first count, emergence, speed index of seedling emergence, length and dry matter of shoot and root, leaf area and shoot/root ratio were evaluated. The experimental design was completely randomized in a factorial 3 x 4 (three lots-high, medium and low vigor x four fungicide doses of carboxin + thiram). Data were submitted to analysis of variance and if significant at 5% probability, adjusted for orthogonal polynomials. It was possible to observe that there were significant differences for the means of the variables germination, first germination count, emergency, emergency speed index, shoot length, root length, aerial part dry mass, root dry mass, leaf area, leaf area ratio and shoot and root ratio. The fungicide doses of 150 to 350 mL i.a./100 kg of seeds result in greater seedling emergence, higher leaf area ratio and increased shoot/root ratio in plants from lots of medium vigor seeds. The fungicide consisted of carboxin + thiram enhances the expression of seed vigor and physiological performance of seedlings growth derived from lots of medium vigor seeds.
NODULATION AND ROOT ESTABLISHMENT OF TWO CLOVER SPECIES GROWN IN PASTURE MIXTURE WITH WHEATGRASS
A field trial was conducted during 2007-2010 at the Institute of Forage Crops, Pleven, Bulgaria to study the nodulation of subterranean clover (Trifolium subterraneum L.) and white clover (Trifolium repens L.) in some pasture mixtures using wheatgrass (Agropyron cristatum L.) as grass component. The treatments tested were: Subterranean clover (100%), White clover (100%), Subterranean clover + Wheatgrass (50%:50%), White clover + Wheatgrass (50%:50%), Subterranean clover + White clover (50%:50%), Subterranean clover + White clover + Wheatgrass (25%:25%:50%). It was found that subterranean clover in a mixture with wheatgrass formed 11.9% more nodules and by 11.0% higher root dry mass than in pure sward. White clover nodulated better in pure sward as compared to mixture and subterranean clover showed better nodulation than the white clover. The results obtained in the present study also indicated that wheatgrass in a mixture with white clover inhibited the root dry mass production by 22.2%. In the triple mixture (wheatgrass, subterranean clover and white clover) no significant differences were observed in characteristics of nodulation and dry mass production.
Biologia
Under natural conditions, plants compete for environmental resources, including by the release of allelopathic compounds with a various spectrum of activity. Therefore, the effect of aqueous extracts of cock's-foot Dactylis glomerata L. on germination and early growth phases and electrolyte leakages of a red clover Trifolium pratense L. was investigated. The 5, 10, and 15% of the aqueous extracts of cock's-foot separately from shoots and inflorescences were used in two type of treatments tested in parallel. In first treatment the red clover seeds were watered directly with the aqueous extracts by eight days of experiment time, in second the seeds were pretreated with extracts for 24, 48 and 72 h and next they were watered with distilled water during experiment time. The results showed that the germination capacity of red clover seeds decreased with increasing concentrations of cock's-foot aqueous extracts. Regardless of the duration of seed treatment with the extracts, the highest inhibition of germination was found when the 15% cock'sfoot shoot extracts was used. For red clover seedlings pretreated with extracts for 72 h, the highest and statistically significant differences in the growth were observed. With the increasing of concentration of cock's-foot extracts significant inhibition of the underground and aboveground organs growth were observed. The increase of fresh and dry masses of red clover seedlings varied depending on the duration of contact with the extracts and their concentrations. The electrolyte leakage, as compared to the control, increased with the concentration of extracts, regardless of types and duration of extracts. The obtained results clearly confirm that leaving biomass of cock's-foot on the field can lead to the release of phytotoxins that may inhibit germination and growth of red clover.
Grass and Forage Science, 1996
Interactions between perennial ryegrass (grass) and white clover (clover) cultivars were investigated at the seedling stage in two experiments: (a) a field experiment in which two clovers, AberHerald and Grasslands Huia, were grown in binary mixture with two grasses, Preference and Ba 10761; (b) a glasshouse experiment in which the same clover/grass combinations were grown in low-N soil either with (+ N) or without (-N) added N. In the field experiment both clovers produced larger and more complex seedlings with Preference, and this was particularly evident in Huia. In the glasshouse experiment grass dry-matter yield was greater in the +N treatment, and this effect increased with time. Clover seedling density and development were suppressed in the +N treatment, and the development of AberHerald was affected more than Huia. Morphological measurements of the clovers showed interactions between clover, grass and N level. In the -N treatment Huia plants were larger and more complex than those of AberHerald, but in +N conditions there was little difference between them. Grass cultivar had an effect on clover via N-level interactions: in +N plants there was no grass effect, but -N plants were significantly larger with Preference. Comparison of the root and shoot morphology of the two grasses revealed no obvious differences that would account for these effects.
Changes in some morphological and physiological parameters (leaves/stems ratio, total plastid pigments content, fixed amount nitrogen) of birdsfoot trefoil (Lotus corniculatus L.) (cv. Targovishte 1) and three subterranean clover subspecies, i.e. Trifolium subterraneum ssp. brachycalicinum (cv. Antas), Trifolium subterraneum ssp. yaninicum (cv. Trikkala) and Trifolium subterraneum ssp. subterraneum (cv. Denmark) were studied in a field trial in the Institute of Forage Crops, Pleven, Bulgaria (2012-15). Crops were grown alone (100%) and in mixtures as follows: birdsfoot trefoil + Trifolium subterraneum ssp. brachycalicinum (50:50%); birdsfoot trefoil + Trifolium subterraneum ssp. yaninicum (50:50%); birdsfoot trefoil + Trifolium subterraneum ssp. subterraneum (50:50%). Leaves/stems ratio for alone grown crops was found: birdsfoot trefoil (1.33), Trifolium subterraneum ssp. brachycalicinum (1.02), Trifolium subterraneum ssp. yaninicum (0.93) and Trifolium subterraneum ssp. subterraneum (0.93). Leaves/stems ratio for birdsfoot trefoil in all mixtures was found be higher as compared to alone grown birdsfoot trefoil-by 13.0% for the mixture with Trifolium subterraneum ssp. yaninicum, by 16.3% for that with Trifolium subterraneum ssp. brachycalicinum and by 20.1% for the mixture with Trifolium subterraneum ssp. subterraneum. Total plastid pigments in birdsfoot trefoil increased in all mixtures: with Trifolium subterraneum ssp. brachycalicinum by 7.4%, with Trifolium subterraneum ssp. subterraneum by 8.1% and with Trifolium subterraneum ssp. yaninicum by 15.6%. From mixtures of birdsfoot trefoil were obtained more fixed amount of nitrogen-from 1.71 kg N/da (with Trifolium subterraneum ssp. subterraneum) to 4.84 kg N/da (with Trifolium subterraneum ssp. brachycalicinum) as compared to alone grown birdsfoot trefoil. Birdsfoot trefoil and subterranean clover in mixtures showed good tolerance, morphological and physiological status.
Seed Science and Technology
Three different seed vigour tests, accelerated aging (AA), Germination Index (GI) and osmotic stress (OS), were evaluated for ranking six reference seed samples of 'Grindstad' timothy (Phleum pratense L.) and 'Lea' red clover (Trifolium pratense L.) according to their physiological potential for storage. AA was conducted at combinations of four temperatures (38, 41, 44 and 48°C) and four times (24, 48, 72, 96 h) and OS by germinating seeds at five osmotic potentials (0. -0.15, -0.30, -0.45, -0.60 MPa). The GI was calculated from daily counts from 2d (red clover) or 3d (timothy) to 10d (complete test) or from counts after 3d and 5d only (simplified GI). The reference samples, which had sustained different degrees of aging before testing, had standard germination percentages between 80 and 98% in timothy and between 79 and 92% in red clover. In timothy, all three vigour tests separated the potentially low-vigour seed from the high-vigour seed lots. The clearest separat...