Microorganisms associated to tomato seedlings growing in saline culture act as osmoprotectant

Abstract

Less than 0.5% of total water in the world is available for human consumption and agriculture. The major part of the world’s water is saline and salinity in soils interferes in germination of seeds and the posterior development of the plant. In order to increase the osmotolerance of tomato, seedlings were associated with Azospirillum brasilense Cd, Azospirillum brasilense Cd transformed bacteria with a plasmid harboring a trehalose biosynthesis gene-fusion or Chlorella vulgaris. Two plant culture media: Hydroponic and Murashige and Skoog were tested. In the first set of studies seedlings were associated to single free cells meanwhile in a second set single and combined free cells were studied. A positive interaction between transformed Azospirillum and Chlorella vulagris and tomato plants was observed. Seedlings showed a salt concentration tolerance, as sodium chloride, up to 200 mM. According to our results, the association of plants with A. brasilense Cd-BIF and C. vulgaris is a viable approach to increase their salt tolerance and biomass, as consequence the possible use of sea water to irrigate horticultural plants.

Use of Microbial Biostimulants to Increase the Salinity Tolerance of Vegetable Transplants

“…An improvement of water use efficiency was also recorded in the salt-stressed inoculated tomato seedlings, but the seedlings inoculated with M (+28.5% and +13.2% with 25 and 50 mM NaCl, respectively, compared to the control seedlings at the same salinity levels) had an almost twice as big increase of WUE than those with B in both salinity treatments (+14.5% and +7.4% with 25 and 50 mM NaCl respectively, compared to the control seedlings at the same salinity levels). Different plant growth-promoting microorganisms have been tested successfully to enhance salinity tolerance of lettuce and tomato plants under various growth conditions [56,[86][87][88][89][90], confirming the beneficial effect determined by the microbial biostimulants used in our trial.…”

Symbiotic association of microalgae and plants in a deep water culture system

“… Cortés-Jiménez et al (2014) discovered that the branch length of all plants co-cultivated with three microalgal concentrations was greater than the control, which had no microalgae. Barone et al (2019) showed an increase in tomato plant shoot development when co-cultivated with Scenedesmus quadricauda .…”

“… Huo et al (2020) also observed a greater shoot growth rate for purple kohlrabi with microalgae (0.80 cm/d) compared to 0.70 cm/d in a hydroponic unit absent of algal biomass. Cortés-Jiménez et al (2014) found that inoculating tomato seedlings with C. vulgaris in a hydroponic nutrient solution increased stem length. The presence of a microalgal population during co-cultivation promotes root respiration and nutrient absorption, resulting in higher nutrient assimilation and better plant shoot development ( Barone et al, 2019 ).…”

Hydroponics with Microalgae and Cyanobacteria: Emerging Trends and Opportunities in Modern Agriculture

“…Huo et al [ 211 ] revealed that the microalgae consortium improved the shoot growth rate of purple kohlrabi (0.80 cm d −1 ) compared to the control (0.70 cm d −1 ) in hydroponic cultivation. Similarly, Barone et al [ 162 ] reported an 130% increase in the total plant length of tomatoes cocultivated with C. vulgaris and S. quadricauda , and Cortés-Jiménez et al [ 224 ] reported an increase in the shoot length of tomato seedlings inoculated with C. vulgaris in the hydroponic system. These significant results suggested that the association of microalgae with plants can increase plant root respiration and nutrient uptake, resulting in better nutrient assimilation and improved plant height.…”