Improved potato microclonal reproduction with the plant growth-promoting rhizobacteria Azospirillum

Abstract

Microclonal propagation in vitro is being actively used in the production of healthy planting material of food and ornamental plants. However, it needs further improvement to increase the growth rates of microclones in vitro and enhance regenerant survivability ex vitro. A promising approach to this end could be inoculating in vitro-micropropagated plants with plant growth-promoting rhizobacteria, specifically Azospirillum. However, the influence of Azospirillum inoculation on microclone behavior throughout the production process, including plant adaptation ex vitro and food crop productivity, has been underinvestigated. In this study, in vitrogrowing potato (Solanum tuberosum L.) microclones were inoculated with Azospirillum brasilense strain Sp245. The microclones were then grown on in soil in the greenhouse and field, with the experiment lasting for 120 days. Rootassociated bacteria were identified immunochemically, and the mitotic index of root meristematic cells was determined by a cytological method. The plant morphological parameters determined were shoot length, number of nodes per shoot, number of roots per plant, maximal root length, leaf area, percentage of surviving plants in the soil, and tuber yield and weight. Our results show that bacterial inoculation of potato microclones in vitro enhances plant adaptive capacity ex vitro and increases minituber yield. The percent survival index of field-grown inoculated plants was 1.5-fold greater than that of uninoculated plants. The overall tuber weight per plant was more than 30 % greater in the inoculated plants than it was in the control ones. For all cultivars on average, tuber yield per square meter increased by more than 45 % as a result of inoculation in vitro. This study is the first to report that Azospirillum inoculation of potato microclones not only improves the quality of planting material produced in vitro but also significantly increases minituber yield through enhancing plant adaptive capacity in the field.

A BACTERIAL ISOLATE FROM THE RHIZOSPHERE OF POTATO (Solanum tuberosum L.) IDENTIFIED AS Ochrobactrum lupini IPA7.2

“…On this basis, it may be considered advisable to continue its study as a potential associate (inoculum) in improving plant microclonal propagation in vitro [7].…”

“…A good perspective is the creation of plant-microbial associations in vitro based on cellular technologies using mixed cell cultures or plant tissues with bacteria of the PGPB category to obtain high-quality, healthy planting stock of agricultural and ornamental plants with increased resistance ex vitro to adverse environmental conditions [5][6][7]. The number of bacterial associates is quite large [5][6][7], but their isolation in situ directly from their habitat and plants, phylogenetic identification and estimation of prospectivity in agrobiotechnology is still of special interest.…”

“…This work illustrates some of these problems and concepts on the example of identification of the bacterial isolate from the potato plants rhizosphere of the Nevskii cultivar when screening strains for possible use in reproduction technologies of planting material based on micro-clonal reproduction in vitro [7].…”

Determination of the treatment period of banana seedlings with rhizobacteria in the control of Meloidogyne javanica

“…Bacteria of the genus Bacillus also have favorable characteristics for inoculant production, since they produce endospores that are spores highly resistant to extremes of temperature, radiation, chemical agents and time and have long shelf life (LIU et al, 2016). The development of micropropagated eucalyptus, kiwi and potato seedlings and control of nematodes have been obtained by the application of rhizobacteria (MAFIA et al, 2009;ERTURK et al, 2010, TKACHENKO et al, 2017, XIANG et al, 2017.…”

БАКТЕРИАЛЬНЫЙ ИЗОЛЯТ ИЗ РИЗОСФЕРЫ КАРТОФЕЛЯ (Solanum tuberosum L.), ИДЕНТИФИЦИРОВАННЫЙ КАК Ochrobactrum lupini IPA7.2

“…та для современных агробиотехнологий (2)(3)(4). Хорошую перспективу имеет создание растительно-микробных ассоциаций in vitro на основе клеточных технологий с использованием смешанных культур клеток или тканей растений с бактериями категории PGPB для получения высококачественного оздоровленного посадочного материала сельскохозяйственных и декоративных растений с повышенной устойчивостью ex vitro к действию неблагоприятных условий окружающей среды (5)(6)(7). Число коллекционных культур бактериальных ассоциантов (5-7) достаточно велико, однако их выделение in situ непосредственно из растений и сред их обитания с последующей филогенетической идентификацией и оценкой перспектив использования в агробиотехнологиях по-прежнему представляет особый интерес.…”