GPC Members Login
If you have any problems or have forgotten your login please contact [email protected]

Plant growth-promoting bacteria enhance plant salinity tolerance

Soil salinity is one of the key abiotic stress factor affecting agricultural productivity worldwide. Every day, nearly 2,000 hectares of fertile agricultural land degrades due to salinity. There are only limited agricultural options to cope with increasing salinification of soils, especially in the case of salt sensitive staple crops such as rice and wheat, productivity of which is seriously curbed due to salinity in many Earth locations. Among the possible options, plant growth-promoting bacteria (PGPB) have a large potential to improve crop plant productivity under salinity, but the progress in application of PGPB has been slow due to lack of non-invasive methodology for testing the efficiency of different bacteria in increasing plant salt resistance. The collaborative study by scientists of Chungbuk National University, South Korea and the Estonian University of Life Sciences looked at foliage volatile emission and photosynthetic traits as potential non-invasive markers to estimate improvements in salinity resistance upon inoculation of rice plants with plant growth-promoting rhizosphere bacterium (PGPR) Brevibacterium linens RS16.

This work was mainly focused on controlling the volatile organic compound (VOC) emission of plants which is a part of plant defense, but it has a large impact to the environment and climate change. Enhanced salinity induces oxidative stress in plants, ultimately leading to a significant reduction in photosynthesis. "Salt stress is observed to have a strong effect on photosynthetic traits and volatile emissions, thus screening photosynthetic characteristics and volatile emissions as non-invasive tools under salinity. This can provide illuminative insight into the severity of stress as well as induction of various primary and secondary metabolic pathways through progression of stress," said Professor √úlo Niinemets of Estonian University of Life Sciences.

In the present study, we used IR29 (salt-sensitive) and FL478 (moderately salt resistant) rice cultivars, to assess foliage carbon assimilation and stress volatile emission rates in response to inoculation by the halotolerant PGPB B. linens RS16 followed by the application of salt in soil. Inoculation of rice plants with B. linens RS16 alleviated the severity of salt-stress, characterized by enhanced foliage photosynthetic traits and decreased stress volatile emissions. Greater changes detected for salt-sensitive cultivar IR29 than for moderately salt resistant genotype FL478. Results showed that salt stress negatively affected foliage photosynthetic characteristics in both rice cultivars. Moreover, salinity enhanced the emission rates of foliage stress volatiles. However, B. linens RS16 inoculation significantly improved photosynthetic characteristics and reduced the volatile emission in salt stressed rice cultivars, compared to control plants.

Read the paper: Science of The Total Environment

Article source: Estonian Research Council

Image credit: CCO Public domain


Scientists Reveal the Relationship Between Root Microbiome and Nitrogen Use Efficiency in Rice

A collaborative team led by Prof. BAI Yang and Prof. CHU Chengcai from the Institute of Genetics and Developmental Biology, Chinese Academy of Sciences (CAS), recently examined the variation in root microbiota within 68 indica and 27 japonica rice varieties grown in field conditions. They revealed that the indica and japonica varieties recruited distinct root microbiota.

New avenues for improving modern wheat

Since the Agricultural Revolution about 12,000 years ago, humans have been selectively breeding plants with desirable traits such as high grain yield and disease resistance. Over time, Triticum aestivum, otherwise known as bread wheat, has emerged as one of the world's most important crops. Together with the growing human population and the changing climate, the demand for wheat with a higher yield and additional resilience is increasing.

Close relatives can coexist: two flower species show us how

Scientists have discovered how two closely-related species of Asiatic dayflower can coexist in the wild despite their competitive relationship. Through a combination of field surveys and artificial pollination experiments, the new study shows that while reproductive interference exists between the two species, Commelina communis and Commelina communis forma ciliata, both can counter the negative effects of this interference through self-fertilization.