Safety Disposal of Rice Straw by Biodegradation Using Streptomyces Tendae

Rice straw is a byproduct formed during rice cultivation. Disposal of rice straw may happen via unhygienic methods such as burning, which is happening in Malaysia and other countries. This study aims to rid rice straw via an eco-friendly biodegradation technique. Biodegradation of rice straw depended on actinobacteria, which were isolated from the cultivated soil of rice and rhizosphere areas in Tabuk region. Out of thirty actinobacterial isolates, only three isolates (S-5, S-12, S-20) biodegraded starch, cellulose, lignin and rice straw powder. The most potent actinobacterial isolate (S-5) was identified as Streptomyces tendae, which effectively biodegraded all polysaccharides of rice straw. Biodegradation of rice straw was associated with a significant reduction in C/N ratio, where the latter fell from 30.4% to 17.2% within 42 d.

Žeme ‘land, ground, earth’ in Lithuanian literature

In Lithuanian literature, žeme ‘land, earth, ground’ is understood as a planet, as one of the four elements, as an element in opposition to water, or as solid ground. It differs from the sky and stands in opposition to it because the sky is good, while žeme is full of things that are unfriendly to people. Žeme is the world with life going on; buildings stand on its surface, people sit, stand or lie on it, etc. It is the most valuable property that can be sold, given, leased, or left as inheritance. People are interested not only in what is going on its surface but also in the layer that is cultivated (soil). People want this layer to grow flowers, trees and grass for them. They find various things in this layer and think that land can hide a lot from them. Žeme is the mother that provides life and shelter after death. It takes care of people, feeds them and talks to them. It also serves as a reference frame on the basis of which people evaluate large and small things or things hanging above it. Žeme can refer to a specific state or a nation that lives in own land, as well as to a person’s native home and lives of their ancestors. Žeme is alive as much as humans are: it has a face, parts of the body and internal organs, it experiences human emotions and has divine powers. Žeme can be of various colours: from the traditional colour of fertile soil, i.e., black, to subtle shades, such as yellowish brown or blue. It is also characterised through most unusual words, such as “sinful”, “juicy”, “slim”, “like caviar” and others. The smell of žeme is also exceptional: it is wet and sour. It smells of oats, barley, summer home – the smell fills people’s hearts with joy, evokes memories and longing.

Influence of fungicide and fertilizer amendments on mycorrhizal association in Quiona (Chenopodium quinoa. Willd.)

Effect of soil factor like alkaline cultivated versus saline non-cultivated soil, fertilization with organic (PYM) and inorganic (DAP) manure and addition of fungicides (Bavistin + Thiram, Difolatan and Thiram) on indigenous VA mycorrhizal fungi was examined in Quinoa (Chenopodium quinoa Willd). DAP in combination with Bavistin + Thiram enhanced the spore population ad decreased mycorrhizal formation. FYM in combination with Difolatan enhanced both. Adverse effects of fungicides were nullified by fertilizers. Activity of Glomus was enhanced in the presence of DAP and Gigaspora was favoured by FYM.

Effects of Atrazine on Chernozem Microbial Communities Evaluated by Traditional Detection and Modern Sequencing Technology

Atrazine is a long residual herbicide commonly used in maize fields. Although atrazine can effectively control weeds and improve crop yield, long-term application leads to continuous pollution in the agricultural ecological environment, especially in the soil ecosystem, and its impact on soil microorganisms is still not clear. Four methods were used in the experiment to clarify the effect of atrazine on the bacterial populations of cultivated soil layers of chernozem in a cold region in different periods: high-performance liquid chromatography (HPLC), colorimetry, microplate, and high-throughput sequencing. The level of residual atrazine in cold chernozem decreased from 4.645 to 0.077 mg/kg soil over time, and the residue gradually leached into deep soil and then decreased after accumulating to a maximum value. Atrazine significantly affected the activities of urease and polyphenol oxidase activity in the soil layers at different periods but had no significant effect on sucrase and phosphatase activity. Atrazine significantly reduced the diversity of microbial carbon source utilization and total activity in soil layers of 0–10 and 20–30 cm but only reduced the diversity of microbial carbon source utilization in the 10–20 cm layer. Atrazine had no significant effect on bacterial populations (10–12 phyla, 29–34 genera), but had a slight effect on the relative abundance of various groups. Atrazine significantly reduced the diversity of bacterial populations in cultivated soil layers of chernozem in a cold region, and the diversity of bacterial populations decreased with decreased residue. This lays a foundation for guiding the safe use of herbicides on farmland in Northeast China.

ISOLATION AND IDENTIFICATION OF BIOFLOCCULANT-PRODUCING BACTERIA FROM CASSAVA CULTIVATED SOIL OF VIET NAM

Microorganisms are found everywhere in the environment and play a leading role in countless natural processes, and amongst them, soil microorganisms play important roles in plant performance by improving mineral nutrition. Soil bacteria possess different biological activities; for example, producing bioactive compounds such as bioflocculant which makes soil smoother and more breathable, as plant growth stimulants or compounds with antibiotic activity. Beside this, the same soil bacteria could also be able to fix atmospheric nitrogen, converting it into the form that plants can use. In order to make a microbial formula from local bacteria capable of producing bioflocculant as well as IAA and fixing nitrogen towards microbial organic fertilizer production for application in cassava cultivation, the bacteria were isolated from cassava cultivated soils and screened for above mention activities. From 37 cassava root and cassava cultivated soil samples collected at different provinces in the North, Central and South regions of Vietnam, 80 strains of bacteria with bioflocculant activity over 50% were screened. In which 3 strains (ĐQT1 Po6, ĐTAN6 Po2 and ĐSBV Po1) possess not only high bioflocculant and IAA producing capacities, but also the ability to fix atmospheric nitrogen. The flocculant rate of these strains was 80÷90% and can produce 6÷11 µg/mL IAA. The selective strains were identified by having an analysis of 16S rRNA gene sequence. The obtained results showed that the 16S rRNA sequence of ĐQT1 Po6 was 100% identifiable to corresponding sequence of Bacillus aryabhattai FORT 21 (Ass.No MG561348.1); and the 16S rRNA sequences of ĐTAN6 Po2 and ĐSBV Po1 had 100% homology with those of Enterobacter sp. (Ass.No KJ184880.1) and Bacillus subtilis SAN1.5 (Ass.No KX098457.1), respectively. These strains are potential candidates as perfect inoculant for biofertilizer.