시설잎들깨에 발생하는 차먼지응애를 친환경적으로 방제하고자 피레스럼(pyrethrum)의 농도별 방제효과를 조사하였다. 2%, 4%, 6% 피레스럼 1,000배 희석액에 대한 차먼지응애 약·성충의 생충률은 약제 살포 3일 후 각각 58.1%, 27.5%, 22.7% 였으며, 5일 후 각각 73.4%, 37.3%, 30.6% 였다. 차먼지응애에 대하여 방제효과가 우수했던 6% 피레스럼 1,000배액와 화학약제인 밀베멕틴(milbemectin EC 2%) 1,000 배액을 이용하여 약제 살포 후 차먼지응애에 대한 약·성충 밀도를 지름 1cm 잎디스크 내에서 조사한 결과, 6% 피레스럼을 차먼지응애의 발생이 예측되는 시기인 5월 10일부터 10일 간격으로 사용한 곳에서 밀도가 낮게 유지된 반면 차먼지응애의 피해가 확인된 후 화학약제를 사용한 곳에 서는 1주 간격 1~2회의 살포로는 차먼지응애의 밀도를 낮출 수 없었으며 1주 간격 3회 살포 이후 밀도가 낮아졌다. 따라서, 시설잎들깨에서 효과 적으로 차먼지응애를 방제하기 위해서는 발생이 예측되는 초기부터 방제제를 사용하는 것이 효과적이다.
충남 금산지역 잎들깨 시설하우스에서 차먼지응애(Polyphagotarsonemus latus)는 5월 하순 최초 발생하기 시작하여 6월 중순에 1차 최대 발생양상을 보인 후 7월 상순부터 급격히 밀도가 증가하여 7월 중순 가장 밀도가 높은 2차 최대 발생양상을 보였다. 방제방법에 따라 발생양상에는 차이가 없었으나 밀도에는 차이를 보여 화학약제를 사용하는 하우스에서 가장 높았고 유기농업자재를 사용하는 하우스에서 가장 낮았다. 이는 크기가 작아 육안으로 관찰할 수 없는 차먼지응애를 방제하기 위해 화학약제를 사용할 경우, 농약 잔류 문제로 지속적인 사용을 못하므로 밀도가 높아지고, 유기농업자재를 사용하는 경우에서는 농약잔류에 대한 걱정 없이 유기농업자재를 지속적으로 사용함으로써 방제가 이루어졌던 것으로 판단된다. 잎들깨 주간내 발생양상을 조사한 결과, 차먼지응애는 접종 25일 후 최대 발생밀도를 보였고, 중엽, 성엽, 신초의 순으로 알과 약성 충의 총밀도가 조사되었다. 그러나 엽장과 차먼지응애 밀도와의 상관성 분석 결과, 상관성이 없어 차먼지응애 발생예찰시 어떤 샘플을 채취해도 정확한 예찰이 이루어질 것으로 판단된다.
Pyrausta panopealis is the major pest in green perilla. The larva weaves a web on the shoot of green perilla and damages. In case of extreme, The larva cuts the main branch of green perilla and the leaf of green perilla isn’t harvested anymore. A field study was conducted to estimate economic injury levels (EILs) and control thresholds (CTs) for P. panopealis injuring green perilla in green-houses. Different densities of P. panopealis ranged from 1 to 20 crops (2 units per crop) per 100 crops on 13. June, early inoculation. The number of injured leaf and the rate of injured crop were increased by 23. June, on the other hand were decreased after that day. Also, the amount of yield sow the same result above. The economic loss time calculated by the ratio of cost managing this moth to market price (C/V) (C: cost managing a moth, V: Market price) was 4.0%. The economic injury level was 5.1 larval per 100 crops. The control thresholds calculated by 80% level of economic injury level was 4.1 larval per 100 crops.
This study was conducted to explain degree of injury caused by P. panopealis larva which is the key component to develop economic injury level or control threshold in green perilla and was carried out in polyvinyl houses at Yuseong Daejeon, Geumsan and Yesan Chungnam from 2004 to 2006. Of 5 major pests in green perilla polyvinyl house, P. panopealis larva injured green perilla leaf by 48.5% on average under no insecticides application. The peak occurrence of P. panopealis adult was early August and late September in 2004 and 2005 studies. The feeding amount of P. panopealis larva among 1st to 3rd instar was not different, but from the 4th instar the feeding amount greatly increased and this result was consistent with daily feeding experiment in which the amount greatly increased from seventh day. The degree of injury which was investigated with different larval infestation levels showed that the degree of injury increased a little but was not different significantly as the density increased. The density of P. panopealis larva in damaged green perilla plant was less than three individuals/plant. This result indicates that P. panopealis adult lays egg on green perilla leaf dispersedly and larva hatched from egg injures only the leaf which egg is layed. These preliminary data seems to be very useful to design economic injury level and control threshold studies for P. panopealis in green perilla polyvinyl house.
According to the preceding survey on insect pests of the green perilla, Perilla frutescens var. japonica HARA, The major pests were Aphis egomae Shinji, Pyrausta panopealis (Walker), Tetranychus urticae Koch, Polyphagotarsonemus latus Banks, Tetranychus kanzawai Kishida at Guemsan, Chungnam, 2004. Aphis egomae causes nearly 100% injury of the green perilla in uncontrolled green houses. A field study was conducted to estimate economic injury levels (ElLs) and control thresholds (CTs) for A. egomae injuring green perilla in green houses. Different densities of A. egomae ranged from 1 to 80 aphids per 100 plants in early inoculation. The mean injurying rate of plant was 2.4% to 40.5% at the end of June at differently inoculated levels. The economic loss time calculated by the ratio of cost managing aphid to market price (C/V) (C: cost managing aphid, V: Market price) in early season (from May to 13. June) was 5.8% and in peak season (from 13. June to 30. June) was 9.3%. Economic injury level in early and peak season was 5.3 aphids per plant and economic injury levels in peak season were 0.6 aphids per plant and 7.6% injured rate of plant. The control thresholds calculated by 80% level of economic injury level in peak season were 0.5aphids per plant and 6.1% injury rate of plant, respectively.
Temperature-dependent development studies of two aphid species, A. egomae and A. gossypii occurring in green perilla greenhouse were conducted at 15~35℃, and 16:8 (L:D h) of light period in the laboratory. The mortality of two aphid species was high in young stages (1st and 2nd). In A. egomae, the mortalitiy increased with increasing and decreasing temperature: the mortalitie at 15℃ and 35℃ were 22.3% and 15.6%, respectively. While the mortalities of A. gossypii increased with increasing temperature: the mortality at 35℃ was 50.0%. The developmental periods of A. egomae and A. gossypii ranged from 20.8days to 5.4days and from 22.6days to 9.1days at 15℃ to 30℃ of temperature resion, respectively, and were 7.2days and 10.7days at 35℃ for each species. The lower developmental threshold temperatures for total nymphs of A. egoame and A. gossypii were 9.9℃ and 4.9℃, respectively and an effective degree-days (DD) for the developmental completion of total nymph were 108.0 DD for A. egomae and 221.2DD for A. gossypii. In green perilla greenhouse, the occurrence period of A. gossypii was earlier about 15 days than that of A. egomae. When the occurrence period of two aphid species was estimated by degree-days based on lower threshold temperatures, A. gossypii occurred earlier than A. egomae in the field. A. gossypii occurred from early April and showed dominant position to late May compared with A. egomae. Whereas, A egomae started to occur from mid April and then were abundant after late May followed by abrupt population crash around late July.
들깻잎 생산 전용품종은 대부분 만생종으로서 우량종자를 채종하고자 할 경우 도복 등이 발생하지 않아 생육관리가 용이하면서 종실 충실도가 높은 파종적기를 설정할 필요가 있다. 이에 중부지역 비닐하우스에서 잎들깨 생산 전용 품종 '잎들깨 1호'를 시험재료로 하여 5월 6일부터 7월 15일 까지 10일 간격으로 8회 파종하여 생육, 도복 발생 여부, 적산온도 및 수량성을 분석하였다. 1. 파종시기가 늦을수록 경장이 짧아지고, 주경절수, 분지수, 화방군수와 화방당 삭수는 감소되었다. 그러나 파종시기가 빠를수록 지상부 생육이 왕성하여 도복이 발생하였다. 2. 개화일수는 파종시기가 늦어질수록 직선적으로 감소되었는데 5월 6일을 기준으로 파종이 1일 지연되면 개화일수는 0.86일씩 단축되었고, 개화기부터 성숙기까지의 결실일수는 29~31일로 파종기 이동에 따른 차이가 없었다. 3. 등숙립율과 종실수량은 5월 6일 파종부터 6월 15일 파종까지 유의성이 없었고, 6월 25일 파종 이후부터 급격히 감소되었다. 4. 등숙에 필요한 적산온도, 도복 발생 여부, 등숙립율과 발아율 등으로 판단하면 만생종 잎들깨 품종의 중부지역 비닐하우스에서 파종적기는 6월 5일(정식 7월 5일)~6월 15일(정식 7월 15일)이었고, 이때 10월 28일~11월 3일경에 성숙되어 종자생산이 가능하였다. 5. 연차에 따라 0℃ 이하로 떨어지는 시기가 일찍 오는 경우 한해에 의하여 노지재배는 고사될 우려가 있고, 중부지역에서는 비닐하우스를 이용한 잎들깨 채종재배가 가능하였다.
This study was conducted to determine feasibility of production system of Perilla frutescens leaf-stem by fertilizing of Sta-Green in pots. Germination rate of Perilla frutescens seeds collected in 2002 was 7%, also germination rate of seeds collected in 2003 was 62%, while germination rate of seeds collected in 2004 was above 93%. Seed germination rate of Perilla frutescens collected in 2004 were higher than seed gathering in 2002. Especially, plant growth and yield of Perilla frutescens grown in pot(The pots was filled with soil mixtures of Sta-Green and Peat Moss mixed with 40:60 ratio.) was the highest. These results indicate that leaf and stem production of Perilla frutescens can be improved by fertilizing of Sta-Green in pots.