Carrot lowering initiation: light effect, photosynthetic pigments, carbohydrates

The present study was aimed at the investigation of the influence of illumination spectrum on physiological processes in carrots (Daucus carota L.) during their evocation, flower initiation and differentiation. The process of flower initiation and morphogenesis was studied in a phytotron facility under treatment with different illumination spectra. The dominating 540-nm component and supplementary components {455-nm, 660-nm and 735-nm), High-performance liquid chromatography with a refractive-index detector was used for the detection and sepa-ration of carbohydrates. Total quantification of photosynthetic pigments was performed by spectrophotometric method. A considerable influence of illumination spectrum on physiological processes in the carrot, especially on the morphogenesis rate, was observed. We conclude that flower initiation processes in carrots can be controlled by tailoring the illumination spectrum and photon flux density. This enables one to accelerate plant cultivation in phytotron conditions. Conclusions: (t) The elimination of both red and far-red or only blue light appeared to suppress floral initiation, under such conditions carrots grew vegetative. In contrary, the elimination of solely far-red light resulted in faster flowering differention. (II) The elimination of solely red or blue light resulted in a low synthesis rate of photosynthetic pigments and conditioned high sucrose content in carrot root. Meanwhile, the elimination of solely far-red light resulted in the opposite effect. (III) Dominating 640-nm light was found toconsiderably contribute to the excitation of the carotenoid antennal complex of the photosynthetic system

The effect of heavy metals and thidiazuron on winter wheat (Triticum aestivum L.) seedlings

Abstract We studied the influence of a synthetic cytokinin-like growth regulator thidiazuron (TDZ) and ions of heavy metals (HMs) -Pb , and Ni 2+ on the growth, generation of superoxide anion, concentration of total peroxides, lipid peroxidation, and catalase activity in the leaves of 7-day-old winter wheat plants (Triticum aestivum L. cv. 'Mironovskaya 808'). It was found that 1 mM solution of HMs inhibited the growth of roots in the following sequence: Zn . HMs inhibited the growth of aboveground parts of young wheat plants, too. HMs stimulated superoxide production by a factor of 1.3-4.9. The content of total peroxides in wheat leaves increased in the presence of HMs in the growth medium. Our analyses showed that malonic dialdehyde (MDA) content in leaves increased with increasing Cu 2+ or Ni 2+ concentra tions in the medium and hardly changed with increasing Pb 2+ or Zn 2+ concentrations. HMs enhanced catalase activity in wheat plants 1.1-2.8-fold at all concentrations studied. All these regularities are indications of HMs-induced oxidative stress in wheat plants. In most treatments, TDZ alleviated the HMs-induced oxidative stress and promoted an increase in Wilkinson tolerance index (WTI). This suggests that the wheat seedlings treated with TDZ were more HMs-resistant than the untreated ones

Effects of sustainable integrated pest management on carrots yiel quality

Relatively large amounts of pesticides are used to control pests in horticulture. Therefore monitoring and forecast systems become very important. By monitoring main pests numbers and considering thresholds it is possible to reduce loss of quality in vegetable yield. Recent years in horticulture noticed a rapid growth of sustainable cropping systems in Lithuania. In this system the same active ingredients of plant protection products can’t be used more than two times per season and harvest interval have to be 1.5 times longer than indicated on the label. For this reason investigation on the efficiency of forecasting models for carrot fly Psila rosae was carried out at the Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in 2011-2012. The aim was to compare carrots yield quality, when insecticides was used according forecasting system iMETOS®sm (sustainable) and conventional cropping systems. For carrot fly control optimization P. rosae emergence model based on soil temperature accumulation system. Yellow sticky traps (IVOGR – System) were used to monitor carrot fly imagoes. Application was made with the same insecticides, but not in the same timeLietuvos agrarinių ir miškų mokslų centro filialas Sodininkystės ir daržininkystės institutasVytauto Didžiojo universitetasŽemės ūkio akademij

The management of Trialeurodes vaporariorum by using two different natural insecticides

Dviejų natūralių insekticidų – Vertimec 0,18 EC (v. m. abamektinas 18 g l-1) ir NeemAzal-T/S (v. m. azadirachtinas A 10 g l-1) – poveikis vienam žalingiausių pomidorų kenkėjų – šiltnaminiam baltasparniui (Trialeurodes vaporariorum Wesw) (Homoptera, Aleyrodidae) – buvo tiriamas LAMMC filialo Sodininkystės ir daržininkystės instituto šiltnamiuose 2014–2015 m. Insekticidų poveikis tirtas purškiant ‘Admiro’ H veislės pomidorų augalus. Preparatas Vertimec 1,2 l ha-1 (0,12 %) buvo veiksmingiausias nuo pomidorų baltasparnių lervų. Abiejų metų dviejų purškimų duomenimis, Vertimec 1,2 l ha-1 biologinis veiksmingumas nuo Trialeurodes vaporiorum kito nuo 64,0 iki 79,3 %. Mažesnės Vertimec normos – 1,0 l ha-1 (0,1 %) – biologinis veiksmingumas tuo pačiu laikotarpiu įvairavo nuo 59,6 iki 73,5 %. Dviejų purškimų NeemAzal-T/S 5,0 l ha-1 (0,5 %) biologinis veiksmingumas buvo beveik toks pat, kaip Vertimec 1,0 l ha-1. NeemAzal-T/S 3,0 l ha-1 (0,3 %) veiksmingumas buvo mažiausias. Augalus nupurškus, fitotoksiškumo požymių nepastebėta. Taip pat neaptikta ir virusinių ligų požymių. Galima teigti, kad šie natūralus insekticidai gali būti sėkmingai naudojami integruotos augalų apsaugos nuo kenkėjų sistemoje, bet norint užtikrinti ilgalaikę augalų apsaugą nuo šio kenkėjo, turi būti naudojami ir kiti, skirtingų veikliųjų medžiagų insekticidaiThe effect of two doses of natural insecticides Vertimec 018 EC (a.i. abamectin 18 g l-1) and NeemAzal-T/S (a.i. azadirachtin A 10 g l-1) on the most widely spread pests in tomatoes - Trialeurodes vaporariorum Wesw (Homoptera, Aleyrodidae), was studied. The investigations of tomato variety Admiro F1 were done at the greenhouse of LRCAF branch Institute of Horticulture in the period of 2014-2015. Vertimec was most effective against larvae of whiteflies in tomatoes at the rate of 1.2 l ha-1 (0.12 %) water spraying solution. In 2014-2015 the biological efficiency of two applications with Vertimec 1.2 l ha-1 (0.12 %) against Trialeurodes vaporiorum warred from 64.0 % till 79.3 %. The lower dose of Vertimec 1.0 l ha-1 (0.1 %) biological efficiency to control Trialeurodes vaporiorum was from 59.6 % to 73.5 %. Biological efficiency of two treatments by NeemAzal-T/S 5.0 l ha-1 (0.5 %) was similar to efficiency of Vertimec 1.0 l ha-1 (0.1 %). Biological efficiency of NeemAzal-T/S 3.0 l ha-1 (0.3 %) was the lowest. Any phytotoxicity and viral disease symptoms on plants were not found. We assume these natural insecticides can be used successfully in an integrated pest management system, but to ensure long-time protection against this pest, especially in high density, other insecticides that have different active ingredients have to be usedAgronomijos fakultetasLietuvos agrarinių ir miškų mokslų centro filialas Sodininkystės ir daržininkystės institutasVytauto Didžiojo universiteta

Augalų produktyvumas : vadovėlis aukštųjų mokyklų studentams

Bibliogr.: p. 251-253Vytauto Didžiojo universitetasŽemės ūkio akademij

The influence of different flowering induction conditions on the growth and organogenesis of common caraway

Lietuvos sodininkystės ir daržininkystės instituto fitotroniniame komplekse atlikti tyrimai, siekiant nustatyti foto- ir termoindukcijos sąlygų poveikį paprastojo kmyno augimui ir organogenezei. Objektas – paprastasis kmynas (Carum carvi L.), veislė – ’Gintaras’. Kmynams suformavus 10 lapų skrotelėje, 120 parų buvo sudarytos tokios žydėjimo indukcijos fotoperiodo ir temperatūros sąlygos: 8 val. – 4 °C, 16 val. – 4 °C. Gauti rezultatai parodė, kad paprastasis kmynas, suformavęs 10 asimiliuojančių lapų skrotelėje, buvo visai pabaigęs juvenalinį periodą ir gebėjo priimti tiek ilgos, tiek trumpos dienos fotoindukcinį bei termoindukcinį poveikį. Kmynų žydėjimo indukcijos periodas nėra ilgas, todėl dar esant žemai temperatūrai augaluose vyko evokacijos bei žiedų iniciacijos procesai. Žema teigiama temperatūra nėra kmynų evokacijos procesus ribojantis veiksnys. Ilgesnis žydėjimo indukcijos fotoperiodas skatino organogenezę, tačiau neturėjo esminės įtakos paprastojo kmyno augimo procesams skirtinguose organogenezės etapuoseThe experiments were carried out in phytotrone complex of LIH. The aim of these investigations was to determine the influence of photo- and thermo- induction conditions on the growth and organogenesis of common caraway (Carum carvi L.), var. ‘Gintaras’. For flowering induction common caraways with 10 leaves in rosette were kept in the phytotron chambers with different photo and thermo periods for 120 days: 8 h – 4 °C; 16 h – 4 °C. Our results showed that for common caraway with 10 assimilating leaves the juvenile period is completely finished. And they are able to accept bough short and long day photo inductive and thermo inductive stimulus. The flowering induction period for caraway isn’t long; therefore the processes of flowering initiation and evocation for caraway were still going during low temperature conditions. Low positive temperature wasn’t limiting factor for evocation processes in caraway. The longer photoperiod during flowering induction accelerated organogenesis, but made no sufficient influence on caraway growth processes during different organogenesis stagesVytauto Didžiojo universitetasŽemės ūkio akademij

Impact of electromagnetic fields on morphogenesis and physiological indices of tomato

The impact of electromagnetic fields of the power of 1800 Am-1 (=H), 1000 Am-1 (~H), 1500 Am-1 (~H), 200 Am-1 (~H) on the morphological and physiological parameters of tomato plants which were affected directly during the whole vegetation by these fields, and in the first and second generation after effect, was studied in vegetation trials in the glass greenhouses of the phytotron complex. When tomatoes were affected with electromagnetic fields directly during the whole vegetation period, seedlings developed rapidly, and formed the biggest leaf area and grew up the highest when affected by the electromagnetic field of 1500 Am-1 (~H). The leaves of tomatoes affected by electromagnetic fields of 1000 Am-1 (=H) and 1500 Am-1 (~H) accumulated the highest content of pigments. The most intensive photosynthesis occurred under the effect of electromagnetic fields of 1800 Am-1 (=H) and 1500 Am-1 (~H). Electromagnetic field of 200 Am-1 (~H) mostly impeded the formation of pigments and decreased the yield. The greater negative effect of electromagnetic fields was established for germination energy of seeds chosen from tomatoes which were affected directly during the whole vegetation period. The effect of electromagnetic field of the power of 1000 Am-1 (=H) and 200 Am-1 (~H) was distinguished most notablyVytauto Didžiojo universitetasŽemės ūkio akademij

Skirtingų paparstojo kviečio (Tritucum aestivum L.) veislių produktyvumo tyrimai

Vytauto Didžiojo universitetasŽemės ūkio akademij

Skirtingų Apiaceae rūšių augalų žydėjimo iniciacija

Straipsnyje žydėjimo iniciacija apibūdinama kaip daugiakomponentis ir daugiapakopis mechanizmas, be daugelio kitų išorinių ir vidinių veiksnių, priklausantis nuo glaudžios fotosintezės, pirminių metabolitų bei fitohormonų sąveikos. Hipotezė grindžiama daugiafunkciu dvimečių augalų žydėjimo iniciacijos modeliu. Darbo tikslas – ištirti juvenalinio periodo procesus ir žydėjimo iniciaciją, įvertinti fotosintetinės sistemos veiklą, išnagrinėti fitohormonų ir cukrų balansą valgomosios morkos (Daucus sativus (Hoffm.) Röhl.) ir paprastojo kmyno (Carum carvi L.) morfogenezės metu. Nustatyta, kad esant ir morkų, ir kmynų ontogenezei juvenalinio periodo pabaiga susijusi su 9 asimiliuojančių lapų suformavimu. Tuo metu šie augalai yra visiškai pasiruošę priimti foto- ir termoindukcijos stimulus. Kmynų žiedų iniciacijos šalčio poreikis yra fakultatyvus, todėl vernalizacija nėra pagrindinis žiedų vystymąsi kontroliuojantis veiksnys. Aktyvi fotosintetinės sistemos veikla ir asimiliatų atjungimas evokacijos proceso metu prieš žiedų iniciaciją pabrėžia asimiliatų (ypač sacharozės) įtaką Apiaceae šeimos augalų žydėjimo iniciacijos procesams. Žiedynstiebio ir žiedyno ašies struktūrų formavimą lėmė sinergetinė ABA bei GA3 ir zeatino bei IAA sąveika, o vystymosi intensyvumas priklausė nuo termo- ir fotoperiodo sąlygųIn this paper the action of flowering initiation is described as a multicomponent and multistep mechanism. This, without other endogenous and egzogenous factors, depends on solid action of photosynthesis, its primary metabolites and phytohormones. Our hypothesis is based on multifunctional flowering initiation model of biennial plants. The aim of this paper was to investigate the processes of juvenile period and flowering initiation; to evaluate the role of photosynthetic system; to describe the balance of phytohormones and sugars during morphogenesis in edible carrot (Daucus sativus (Hoffm.) Röhl.) and common caraway (Carum carvi L.). It was determined that the end of juvenile period in both carrot and caraway ontoge¬nesis is related to formation of 9 assimilated leaves and with full competence to accept the stimulus of photo and thermo induction. Cold requirement for flower initiation in caraway is facultative therefore vernalization is not the main factor which strictly controls floral development. Active action of photosynthetic system and release of assimilates during evocation processes before flower initiation highlights the role of assimilates (especially of sucrose) in flowering initiation processes of Apiaceae plants. Synergistic interaction of ABA/GA3 and zeatin/IAA and antagonistic interaction of ABA/IAA determined the formation of flowering stem and flowering axis structures; however the development intensity depended on thermo and photoperiodic conditionsVytauto Didžiojo universitetasŽemės ūkio akademij