Response ofMatsucoccus thunbergianae males to synthetic sex pheromone and its utilization for monitoring the spread of infestation
Attraction of (2E,4E,6R,10R)-4,6,10,12-tetramethyl-2,4-tridecadien-7-one [1; (6R,10R)-matsuone] and its antipode [2; (6S,10S)-matsuone] toMatsucoccus thunbergianae males was studied in the laboratory and in the field. They showed stronger response to1. In laboratory bioassays, the threshold concentrations for male attraction with1 and2 were 16 fg and 150 pg, respectively. In the field, during the first two days after traps were set, traps baited with 50 µg of1 on rubber septa or filter paper rolls caught more males than control traps. Between the sixth day and the tenth day after traps were set, in a daily trap catch experiment, the traps with 50 µg of1 on filter paper rolls caught more males than control traps on one day only, whereas those on rubber septa were always effective. The shape of the traps did not affect male catches. Males were caught on pheromone traps in locations where no scales were found by the customary detecting procedures.
Hazard rating of coastal pine forests for a black pine bast scale using self-organizing map (SOM) and random forest approaches
This study examined the effects of environmental factors on the abundance of black pine bast scale (BPBS), Matsucoccus thunbergianae Miller and Park, in coastal disaster prevention pine forests. Geographical factors, soil conditions and forest stand conditions were measured to evaluate the hazard rating for the occurrence of BPBS at 35 plots in the coastal forest stands. A combination of a self-organizing map (SOM), which classified the samples according to their characteristics, and a random forest model, which predicted the probability of the BPBS occurrence from SOM results, were used to assess the hazard rating. Our results showed that climate, tree size, and tree health are major factors determining the abundance of BPBS. BPBS was more common in low latitude coastal forests, suggesting that warmer conditions were favorable to BPBS population buildup. Tree size also influenced the abundance of BPBS, which was higher in forests composed of larger trees (greater DBH). Finally, BPBS was also more abundant in areas with high soil salinity and clay-loam soil, and north-facing slopes where tree vigor was lower. These results can provide useful information for improved coastal pine forests management against BPBS.
Impact of long and short term irrigation of a sodic soil with distillery effluent in combination with bioamendments.
The study reports the effects of irrigation of a sodic soil with post methanation effluent (PME) of a distillery. Impact of long term effluent irrigation in the field (10 years) and short term effluent irrigation using different doses of PME in the laboratory (30 days) was studied in combination with three bioamendments i.e. farmyard manure, brassica residues and rice husk. Impact on various soil properties like EC, pH, total organic carbon (TOC), total Kjeldahl nitrogen (TKN), available phosphorus, exchangeable K, Na, Ca, Cl, microbial population and soil enzyme activities were studied. Long term application of PME proved useful in significantly increasing TOC, TKN, K, P and soil enzymatic activities in the soil but tended to build up harmful concentration of Na, that could be chelated by bioamendments. In short terms studies, application of 50% PME along with bioamendments proved to be the most useful in improving the properties of sodic soil and also favoured successful germination and improved seedling growth of pearl millet.