Šviesos spektro sudėties įtaka bulvių (Solanum tuberosum L.) stiebagumbių apikalinio dominavimo slopinimui

Abstract

Eksperimentai vykdyti Lietuvos agrarinių ir miškų mokslų centro Sodininkystės ir daržininkystės instituto Augalų fiziologijos laboratorijos fitotroniniame komplekse. Tirtas šviesos spektro sudėties poveikis sėklinių bulvių stiebagumbių dygimui bei apikalinio dominavimo slopinimui. Bulvių stiebagumbiai tris savaites iki sodinimo švitinti kietakūnio apšvietimo komplekse, kurio moduliai sudaryti iš raudonos 638, papildytos mėlyna 445, raudona 660, raudona 669, tolimąja raudona 731 bei UV 385 nm šviesa, taip pat po fluorescencine lempa. Palyginamieji stiebagumbiai laikyti fitotrono kameroje be apšvietimo. Skirtinguose apšvietimo deriniuose bendras fotonų srauto tankis buvo palaikomas vienodame lygyje (50 pmol cm.2 s.1). Eksperimento pabaigoje buvo vertinamas bendras bei skirtingose stiebagumbio dalyse sudygusių pumpurų skaičius, pumpurų spalva, stiebagumbio masė, sukauptų sacharidų kiekis apikaliniuose pumpuruose, apikalinių pumpurų zonose ir šoninėse zonose. Nustatyta teigiama šviesos spektro sudėties įtaka bulvių stiebagumbių dygimui. [...]

Vegetative experiments were carried out in a phytotron complex at the Laboratory of Plant Physiology, Institute of Horticulture, Lithuanian Research Centre for Agriculture and Forestry in 2008. The investigation was focused on Solanum tuberosum L. var. ‘Solara’. Twenty-one days before planting, potato tubers had been illuminated with the basal red 638 nm light emitting diodes supplemented with 445, 660, 669, 731, UV 385 nm components and then with high-pressure sodium lamps. Reference potato tubers were stored in the phytotron chamber without light. To assess the impact of solid-state lighting spectral composition on the germination of potato tubers, the quantitative method was applied to determine the number and percentage of germinated shoots in the upper, middle and bottom parts of tubers, the weight of tubers (g and %), sugar content and composition in potato tuber shoots and in shoot areas. Studies have shown a positive effect of the spectral composition of light on potato tuber germination. Irradiated tubers shaped short, compact buds. If potato tubers were kept in the dark, their buds were pale yellow in colour and brittle. The greatest inhibition of apical domination in potato tubers was observed at the solidstate lighting spectral composition of blue 445 nm, red 638 nm and red 669 nm (L4) light. The total maximum number (94.40%) of germinated shoots was observed at the solid-state lighting spectral composition of blue 445 nm and red 638 nm light (L3). The impact on the germination of potato tubers was negative at the solid-state lighting composition with UV 385 nm. A higher sugar content was found in the apical buds of tubers that had been kept in the dark because of a more intensive transport of assimilates. Sugar content in buds and bud growing areas directly depended on the intensity of sprouting