SAP-sucking insect activity in Macquarie Valley cotton crops was reasonably low this year but growers kept a vigilant eye on Silverleaf whitefly numbers from flowering to picking.
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Narromine-based agronomist Ryan Pratten of Muldoon Pratten Ag Consulting, said insect pressure was lower than average, particularly from green vegetable bugs and mirids.
"Green vegetable bug numbers were very low, mainly because of the warmer growing season," he said.
"They are normally active in a cold wet year, so spraying for these was minimal this season.
"The presence of mirids was also below average, but spraying was still required in most fields."
However, silverleaf whitefly worried growers because of its potential to significantly discount price well after the crop was picked.
"It was a major insect this year and I spent a lot of time on it with clients," he said.
"It's an insect that likes a hot dry summer and that's the way the season was in late December and early January."
Mr Pratten said even the Cotton industry staff were active conducting information days.
Silverleaf whitefly is a major issue all of its own, according to Mr Pratten, who said its activity was not "clear-cut" like mirids and green veggie bugs.
"Most sucking insects drill into squares and bolls but it's the sticky honeydew these flies leave on the plant while sucking that causes the problem".
The sticky honeydew residue has a very low melting point.
"When they put the cotton into the spinners the friction melts the honeydew which spreads on the machine and can gum it up," he said.
Control in the paddock is expensive at a cost of $50 to $90 a hectare just to purchase the effective chemical.
"This insect generally shows up at Christmas time around the early flowering stage and continues to build up season long.
"Numbers can build quickly as their lifecycle ranges from 18 to 28 days."
"We will combine data from this season with last season which also had high silverleaf whitefly numbers to develop strategies for next year."
Three diseases caused quite a bit of seedling disease early in the season, which Mr Pratten said was associated with fluctuating temperatures.
"Black root rot, rhizoctonia and pythium diseases affected our crop establishment and early stage development.
"Cool temperatures and wind fluctuations were the main causes when associated with fields that had a strong cotton history.
Of major concern late in the season was boll rot.
"That was pretty significant this season in the high yield potential fields."
On a positive side, Mr Pratten said there was not a significant amount of sclerotinia this season compared to the wet season two years ago.