extrinsic ice nucleation agents such as ice-nucleation-active (INA) bacteria and intrinsic nucleation agents synthesized by plants. The working hypothesis, first postulated in the early 1980s, was that by controlling extrinsic (external, nonplant
Tomato plants (Lycopersicon esculentum Mill. ‘US 28’) and plant parts ranging in fresh weight from 6 mg to 180 g were frozen in the presence and absence of epiphytic ice nucleation active (INA) bacteria. As weight increased, freezing temperatures rose from —10.5° to — 2°C in the absence of INA bacteria but varied from —3° to —2° in inoculated samples. The freezing behavior of entire plants could only be estimated using small plant parts when INA bacteria were present. INA bacteria were detected by a plate harvesting method. The fraction of tomato stem sections frozen increased with increasing exposure duration at constant temperature.
Citrus huanglongbing (HLB or citrus greening) is one of the most destructive diseases of citrus worldwide and was discovered in the Western Hemisphere in 2005 ( Gottwald 2010 ). In Florida, HLB is associated with the phloem-limited bacteria
microorganisms. The number of cultivable microorganisms was determined by agar plate dilution method ( Hua et al., 2012 ). Beef peptone medium was used for the culture of bacteria before counting after 24 h of incubation at 37 °C, and PDA medium was used for
at 100 °C for 20 min, and its electrical conductivity was read for the second time EC ( C 2 ) after being cooled. Based on the following equations, the desired indices were calculated in terms of percentage ( C 2 ). Bacteria population. The samples
strongly correlated. VOCs could potentially be used as communication signals between bacteria. A recent study by Jones and Elliot (2017) found that Streptomyces exploration, a novel form of growth and development by the bacteria when in a multispecies
The number of bacteria in the basal 5 cm of the stems of cut rose flowers (Rosa hybrida L. cv. Sonia) stored in water for 1 to 4 days was positively correlated with the number of bacteria in the water. Subsequent dry storage of the flowering rose stems resulted in an increase in the number of bacteria in the stems, similar to that occurring in stems that were held in water. Low temperatures during dry storage (SC) reduced the reproduction rate of bacteria in the stems. Use of aluminum sulfate (0.8 g-liter-`) during the rehydration period before dry storage limited the number of bacteria in the stems and prevented their subsequent increase during dry storage.
Some drip irrigation systems installed in central and south Florida citrus groves have ceased to function properly because of filter and emitter clogging. The most serious clogging has been a slime formed by filamentous sulfur bacteria. The most abundant sulfur bacteria was Thiothrix nivea Robenhorst, a common inhabitant of warm mineral springs in Florida. The bacteria oxidize H2S to S and can clog small openings within a brief period of time. Beggiatoa sp., a sulfur bacteria, was also found in the slime although the organism occurred most frequently in emitter orifices.
Another serious clogging factor has been Fe deposits in the form of filamentous, gelatinous ochre. The Fe deposits were associated with iron bacteria. The sticky sludge adhered to filters, grooves, and orifices of emitters. Iron sulfide clogged filter screens and accumulated in the grooves of some emitters.
et al., 2005 ). Research studies have shown the antimicrobial potential of TiO 2 nanoparticles on bacteria, fungi, and viruses ( Adams et al., 2006 ; Anpo, 2000 ; Choi et al., 2009 ; Dancer, 2008 ; Page et al., 2009 ; Tsuang et al., 2008 ; Wu
addition, NH 4 + can be easily transformed into nitrate (NO 3 − ) via nitrification and NO 3 − may be lost in harmful forms of nitrous oxide (N 2 O) and nitric oxide (NO) by denitrifying bacteria or leaching through the soil to contaminate groundwater