The standard for the control of tea inchworm gb 9194mur88

This standard is applicable to the control of tea inchworm (BoarmiaobliquahypulinaWehrli) in adult picking tea garden.

1 terminology

1.1 the pest population density when the increment of the economic loss caused by the control standard is equal to the increase of the cost of preventing the loss under the specified control period.

1.2 larvae hatched in the same egg block in the worming center gather on the same picking surface to do harm. A gathering point is a worming center.

2 prevention and control standard

2.1 according to the characteristics of low leaf intake and strong aggregation of the low instar larvae, the peak and late stage of the second instar larvae was determined, that is, the second instar larvae accounted for the total number of larvae.

60% is the appropriate time for prevention and control.

2.2 controlling the population density of tea inchworm larvae occurred in the adult picking tea garden. when the population density reached 4500 per mu or 10 per meter long tea, the tea garden needed to be sprayed.

3 investigation of insect population density

3.1 investigation time

3.1.1 the occurrence period of tea inchworm larvae of each generation.

3.1.2 Sunny day, before 10:00; cloudy day, all day.

3.2 investigation methods

3.2.1 in the tea garden with high population density and indistinguishable hair center, samples were taken with parallel lines, 20 to 40 points per mu according to the tea line and 1 m long tea line per point, the number of larvae at each point was checked, and the insect population density per mu was calculated by formula (1).

D=444.4a/b...

(1) in formula: d ── population density per mu, head

A ── survey total number of worms, head

B ── investigates the length of the tea line, m

444.4 ── the row spacing of tea rows in general tea garden is 1.50m, and the tea length per mu of tea garden area is 444.4m.

3.2.2 A tea garden with a clear worming center can investigate the worming center and the number of worms. Within the investigated area of the tea garden, first check the number of worming centers in the whole garden and mark them, and then randomly check the number of worms in 10%-20% of the worming centers. Calculate the population density per mu with (2) and (3) formulas.

N=n0/p0...

(2) d=Pn/S...

(3) where n ── averages the number of worms in each hair center, head

N 0 ── was sampled to check the total number of worms in the hair center.

P0 ── was sampled to check the number of worm centers.

D ── population density per mu, head

P ──, the number of parasitic centers in the whole garden

S ── area of the whole garden, mu.

(4) Control effect

In the tea garden that reaches the control standard, the pesticide with high efficiency, low toxicity and low residue should be selected during the appropriate period of control. Under the premise of ensuring the spraying quality, the control effect should be more than 95% after 3 days of spraying.

Appendix A

Correction of population density of control standard insect

(supplement)

Because there are many kinds of natural enemies of tea inchworm, such as Apantelessp., OxyopessertatusL., nuclear polyhedrosis virus and parasitic bacteria, they all have great inhibitory effect on the occurrence of tea inchworm. Therefore, when applying the control standard, the population density of the control standard can be modified by the following formula:

I'=I/ (1murp)

In the formula: I ── original control standard pest density, head / mu

I '── revised control standard population density, head / mu

P predation and parasitism rate of natural enemies of ──,%.