• Title/Summary/Keyword: emergence rate

Search Result 621, Processing Time 0.033 seconds

Seedling Emergence of Dry-seeded Rice Varieties under Two Soil Moisture Regimes (건답직파에서 토양수분조건에 따른 벼 품종의 출아특성)

  • 이변우;명을재
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.39 no.5
    • /
    • pp.502-511
    • /
    • 1994
  • Investigated were the relationships between plumule elongation characteristics and seedling emergence of 98 varieties including native, improved and red rice varieties of Korea, and varieties from U.S.A., Italy, Japan, etc. under proper and excess soil moisture regimes. Under excess soil moisture condition the seedling emergence and establishment rates were much lower in most of the varieties and the seedling emergence rates were delayed substantially in all varieties employed. The seedling emergence rates were lowest in dwarf and some semi-dwarf varieties showing poor plumule elongation under proper soil moisture condition. The seedling emergence and establishment rates were significantly correlated with the length of mesocotyl, coleoptile and incomplete leaf under both soil moisture regimes, and with the lower first and second internode length under excess soil moisture condition. Average emergence duration showed significant negative correlation with the length of mesocotyl, coleoptile and incomplete leaf under both soil moisture regimes and significant positive correlations with the first and third lower internode length. Based on the standardized partial regression analysis only the variations of mesocotyl and coleoptile length contributed significantly to the varietal difference in seedling establishment rate, and so did the variations of mesocotyl and incomplete leaf length to the varietal differences in emergence speed. In conclusion varieties with greater elongation characteristics of mesocotyl, coleoptile and incomplete leaf are desirable for higher and speedy seedling establishment in dry-direct seeding.

  • PDF

Effects of MA Storage with Fine Holes For Red Chili Pepper and Red Bell Pepper Fruits (홍고추 및 홍피망의 미세공 MA저장 효과)

  • 이귀현;정천순
    • Food Science and Preservation
    • /
    • v.8 no.2
    • /
    • pp.125-130
    • /
    • 2001
  • The effects of modified atmosphere(MA) storage for fresh red chili pepper and red bell pepper fruits were investigated with storing in polyethylene film with various fine holes. During the storage of the both pepper fruits, the weight loss, color change, mold emergence, and firmness were evaluated. The weight loss of pepper fruits packaged without holes on film was less than 3%, even though it was each 50% and 25% for non packaged red chili pepper and red bell pepper fruits. The rates of mold emergence of red chili pepper and red bell pepper fruits were reached to each 60% and 50% at the end of storage period as stored in film without holes. However, the rate of mold emergence of pepper fruits was lowered when fruits were stored in MA with low relative humidity (70∼80%). The color and firmness of pepper fruits were not much changed when fruits were stored in MA with high humidity.

  • PDF

Seasonal Pupation, Adult Emergence and Mating of Black Soldier Fly, Hermetia illucens (Diptera: Stratiomyidae) in Artificial Rearing System

  • Park, Kwan-Ho;Kim, Won-Tae;Lee, Sang-Beom;Choi, Young-Cheol;Nho, Si-Kab
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.21 no.2
    • /
    • pp.189-191
    • /
    • 2010
  • The black soldier fly, Hermetia illucens, has a worldwide distribution in the tropics and warm temperate regions and is active in the Korea from May through October. This species colonize a wide variety of decomposing vegetable and animal matter and oviposits in a variety of decomposing materials. In this study, how the black soldier fly pupation, adult emergence and mating rate changed with season at the artificial rearing system was investigated. The black soldier fly larvae and pupae were reared under laboratory condition ($27^{\circ}C$, 60% R.H.). In this study, under the laboratory condition, pupation and adult emergence were not influenced by season, but the data shows definitely different mating numbers throughout whole year. The time of the day is changed with seasons and it influence to mating on artificial rearing. To culture the black soldier fly throughout the year in Korea needs a more deep study under the artificial rearing system.

Effects of temperature and water management in rice fields on larval growth of Pantala flavescens (Odonata: Libellulidae)

  • Bosomtwe Augustine;Jinu Eo;Myung-Hyun Kim;Min-Kyeong Kim;Soon-Kun Choi;So-Jin Yeob;Jeong-Hwan Bang;Owusu Danquah Eric
    • Korean Journal of Environmental Biology
    • /
    • v.39 no.4
    • /
    • pp.536-541
    • /
    • 2021
  • Pantala flavescens is a dominant Odonata species in the rice fields in Korea. To determine the effects of different temperatures on its larval growth and emergence, field and laboratory experiments were conducted. Larval growth was also monitored in mono-cropping and double-cropping rice fields. The growth of larvae was monitored every week by measuring the head width. In the field experiment, no difference was found in larval growth and emergence between the control temperature and +1.9℃ of the control temperature. The larval growth was greater at 23℃ than at 20℃ laboratory temperatures, and no emergence was recorded at either temperature after eight weeks of monitoring. There was a quadratic relationship between larval growth and temperature in an incubator at five temperature regimes of 15, 20, 25, 30, and 35℃. Midseason water drainage caused the extinction of the existing individuals and newly hatched larvae dominated after re-watering in the rice fields. Larval size was greater in double-cropping fields than in mono-cropping fields in late July but the tendency was reversed in early August. The results of this study suggest that temperature warming will directly promote the larval growth of P. flavescens and indirectly influence seasonal growth via changes in water management in rice fields.

[ $CO_{2}$]-Narcosis Time Favorable for Colony Development in the Bumblebee Queen, Bombus terrestris

  • Yoon Hyung Joo;Kim Sam Eun;Lee Sang Beom
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • v.11 no.1
    • /
    • pp.21-25
    • /
    • 2005
  • As a means for year-round rearing of bumblebee, CO$_{2}$ -narcosis time favorable for colony development was identified in Bombus terrestris. CO$_{2}$ -narcosis time divided into five classes: 11 days of adult emergence (A-11), the day of adult emergence (A-0), late pupal stage (LP), middle pupal sta ge (MP), and early pupal stage (EP). In egg-laying characteristics, the oviposition rate of LP, A-11 and A-0 was over 76.0$\%$, but that of MP and EP was less than 61.1 $\%$. At the same time, the days needed to first oviposition shortened to 9.8 ­10.5 days in A-11, A-O and LP, comparing to 13.7 -16.1 days in MP and EP. The rate of colony foundation, progeny-queen produced and period of colony foundation of A-11 were the best results in among those at different CO$_{2}$-treatment time. The number of worker produced was 109.2 -110.5 in A-H, LP and A-H, comparing to 82.0 - 86.8 in MP and EP. Also, the number of progeny-queen produced of A-H, A-O and LP was 36.1, 41.0 and 71.3, respectively, which corresponded to 1.5 - 3.1 fold higher than MP and EP. Taken these together, CO$_{2}$-narcosis time favorable for colony development was determined to be 11 days of adult emergence. Also, the day of adult emergence and late pupal stage showed a positive effect on the oviposition and colony development in CO$_{2}$-narcosis time.

Barley Varietal Differences in Germination and Emergence Capacity under Different Water and Salt Stress Conditions (수분 및 Salt Stress조건하에서 대맥품종의 발아력과 출현력의 차이)

  • Chun, J.U.;Lee, E.S.;Chung, D.H.;Chung, T.Y.
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.28 no.1
    • /
    • pp.122-127
    • /
    • 1983
  • Germination and seedling emergence of 40 barley cultivars and lines having been bred in Korea were studied under different water and salt stress conditions containing different sucrose and KC1 concentration in laboratory at Suweon. This study revealed that the barley cultivars and lines differed markedly in their emergence rate index(ERI), total stand(TS), coleoptile length, seedling height, top and root weight. Those characters of the most cultivars were progressively reduced as water and salt stress increased. Jogangbori, Dongbori 1, SB 77460 and SB 77415 were less sensitive to both stress and will be useful for breeding sources. ERI was highly correlated with TS, coleoptile length and seedling height. ERI and TS between two different solutions were correlated each other, and this study indicated that for screening the varieties or lines tolerant to water and salt stress, both ways were available and should be screened genetic materials with a good germination and emergence rate in I stress conditions.

  • PDF

Host Dependent Oviposition and Development of Azuki Bean Weevil (Callosobruchus chinensis L.) in Different Leguminous Seeds (기주에 따른 팥바구미(Callosobruchus chinensis L.)의 산란 선호성 및 성장)

  • Kim, Seul Gi;Lee, Su Mi;Park, Jun Hong;Song, Kuk;Shin, Byung Sik
    • Korean Journal of Environmental Biology
    • /
    • v.34 no.4
    • /
    • pp.346-352
    • /
    • 2016
  • To investigate the oviposition preference and development of azuki bean weevil (Callosobruchus chinensis L.), the following six different leguminous seeds were used in this study: red bean (Vigna angularis (Willd.) Ohwi & Ohashi), black soybean (Glycine max (L.) Merr.), soybean (Glycine max (L.) Merr.), seoritae (Glycine max (L.) Merr.), small black bean (Rhynchosia nulubilis) and kidney bean (Phaseolus vulgaris var. humilis Alef.). In the study of oviposition preference, the numbers of eggs per leguminous seed on red bean, black soybean, soybean, seoritae and small black bean were 1.23, 0.61, 0.69, 1.05 and 1.13, respectively. The maximum daily number of eggs was observed at 48 hours and the minimum was at 96 hours. According to each host leguminous seed, developmental time for each host seed was different. The shortest adult emergence time was on red bean (25.27 days). The other five leguminous seeds increased or doubled the adult emergence time. Adult emergence rates feeding on red bean, seoritae, black soybean, soybean, small black bean were 83.33%, 28.23%, 27.87%, 20.44%, and 11.59%, respectively. Emergence rate on red bean was four times higher than the rate on other seeds. The longevity of emerged female adults was almost all longer than that of males. The male adults weighed the lowest of feeding on small black bean. Female adults weighed the lowest of feeding on soybean. Adult weights were the heaviest for both males and females feeding on red bean. As a result, hosts of azuki bean weevil could decrease oviposition rate, emergence rate, adult longevity, and adult weight but increase emergence time. Especially in kidney bean, adult was not completely emerged. No eggs were laid. These results suggest that there might be emergence inhibitors in kidney bean. These imformation might be used to control damages caused by azuki bean weevils.

Effect of Varous Factors on Emergence and Control of Sagittaria pygmaea Miquel (올미의 출아(出芽) 및 방제(防除)에 미치는 환경요인(環境要人)의 영향(影響))

  • Han, S.S.;Ryang, H.S.;Konnai, M.;Takematsu, T.
    • Korean Journal of Weed Science
    • /
    • v.5 no.1
    • /
    • pp.35-42
    • /
    • 1985
  • This study was carried out to investigate the effect of environmental factors affecting emergence and control of Sagittaria pygmaea Miquel in greenhouse. Emergence of S. pygmaea delayed as the amount of rice straw increased. When the tuber was sowned at 5 to 7㎝ soil depth the emergence of S. pygmaea delayed more in the hard condition of soil than that of the soft condition the large size tuber of S. pygmaea showed less control rate than the small size one at the rate of 2 to 3㎏ prod/10a of butachlor-naproanilide mixtures. The tubers of S. pygmaea seeded at the deeper soil depth decreased weeding efficicy of this mixture. Butachlor-naproanilide mikture showed higher weeding effects at the high temperature and at 2 to 4cm depths of water management than those of the low temperature and at 0cm and 6cm water depths. Weed control rate increased as the rate of butachlor-naproanilide mixture increased. The rate of 4㎏ (prod.)/10a showed good weed effect regardless of application times till 7.5 leaf stage of S. pygmaea. Tuber production of S. pygmea increased as the application time of mixture delayed.

  • PDF

Effects of Temperature on the Development of Delia platura(Diptera: Anthomyiidae) (씨고자리파리의 발육에 미치는 온도의 영향)

  • 이건휘;최만영;한상수;김상수
    • Korean journal of applied entomology
    • /
    • v.39 no.1
    • /
    • pp.21-24
    • /
    • 2000
  • These studies were conducted to investigate the effect of temperature on the developmentof Delia platura (Meigen) under a laboratory condition at five different temperatures. The developmentalperiods of D. platurcr from egg to adult emcrgence at the temperatures of 11, 15, 19, 23, and 27$^{\circ}$C were67.8k 14.5, 43.7t-9.4, 31.2-t-7.0, 22.4k4.9, and 18.3k4.1 days, respectively. Based on these results,threshold temperature of development and effective cumulative degree-day (DD) for overall developmentwas 0.6"C and 579.8 DD, respectively. Generation of time D. pluturci averaged 30.8 days, and meannumber of eggs produced per female was 246.5 k 16.9 at 23$^{\circ}$C. Hatching rate and emergence rate curvesin relation to the temperature was dome shaped with the peak of 90.0 and 85.2% at 23"C, it wassuggesting that hatching and emergence were inhibited by high temperature above that temperature.Pupation rate of the insect reared on garlic and on onion were higher than those reared on other diets.Oviposition of D. platum usually began 7-9 days after emergence at 23$^{\circ}$C. Females laid about 3-4 eggsin a day. Oviposition of the females peaked at the age of 12- 18 days after emergence. of 12- 18 days after emergence.

  • PDF

Effect of Pathogenic Fungi on Growth of Alfalfa Seeding (병원성사상균이 Alfalfa 유식물의 생육에 미치는 영향)

  • Choi, Ki-Chun;Kim, Jong-Seop;Lim, Kye-Tack;Kim, Dong-Hoo;Kim, Kwang-Hyun;Yoon, Chang;Moon, Soung-Ju;Chun, Woo-Bock
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.17 no.2
    • /
    • pp.141-149
    • /
    • 1997
  • This study was conducted to investigate the effects of pathogenic hngi(Fusarium culmorurn, Fusarium oxyspomm fsp. lycopersici, Fusaiurn solani, Rhizoctonia solani), pregermination time(0, 6, 9, 12, 18, 24, 48 hrs.) and temperature($12^{\circ}C, 18^C{\circ}, $28^C{\circ}$) on growth of alfalfa seedling. The survival rate of alfalfa was decreased by pathogenic hngi and treatment of pregermination and survival rate of alfalfa resulted in higher than that of nontreatment of pregermination. Pathogenicity of fungi was increased as increased the temperature(P<0.05). The emergence rate of alfalfa was decreased when pathogenic fungi were inoculated. However, the emergence rate was increased when seeds were pregerminated(P<0.05)

  • PDF