Semi-forcing Culture Research Articles

Glycine betaine material affects the growth and yield of asparagus in the long-term harvest production system in a semi-forcing culture

Glycine betaine material affects the growth and yield of asparagus in the long-term harvest production system in a semi-forcing culture

Effect of Low-Temperature Tolerant Rootstocks on the Growth and Fruit Quality of Watermelon in Semi-Forcing and Retarding Culture

Watermelon grafting is practiced in order to improve tolerance to poor environments such as low temperature. This study was conducted to investigate the effect of low-temperature tolerant bottle gourd (Lagenaria siceraria) rootstocks on the growth and fruit quality of watermelon in semi-forcing and retarding culture where plants were exposed to low or high temperature. Five bottle gourd accessions (FR79, IT207112, BG702, BG703, and FRD22) with low temperature tolerance were evaluated as rootstock for the watermelon scion ‘Sambokkul’. Non-grafted watermelon and watermelon grafted onto commercial rootstock ‘Shintozwa’ (Cucurbita maxima D. × C. moschata D.) or ‘Bullojangsaeng’ (L. siceraria) were used as controls. Watermelons were cultivated in spring (April to June, semi-forcing culture) and autumn (August to October, retarding culture). The responses to low-temperature, growth, yield, and fruit quality differed depending on the rootstocks and growing season. In semi-forcing culture, the monthly averages of daily and minimum temperature in April were, respectively, 13.4 and 1.5 °C. Although the low temperature of the early growth stage suppressed the initial growth of watermelons, grafting mitigated the low-temperature stress. The fruit quality of non-grafted watermelons was greater, but the fruit mass was the lowest (4.8 kg). Grafting onto ‘Shintozwa’ increased the fruit weight (7.0 kg) but reduced the fruit quality. Grafting onto bottle gourd rootstocks had high affinity, good root growth, tolerance to low temperature, and little effect on fruit quality. In retarding culture, the temperature conditions in early and late growth were very high and low, respectively. The growth and fruit quality of grafted watermelons were not superior to those of non-grafted watermelons. Accordingly, these results suggest that watermelon grafting onto the bottle gourd rootstocks may increase the low-temperature tolerance, especially in the early growth stage, and the marketable yield without a reduction in fruit quality. The most promising accession for this purpose was found to be ‘FR79’.

Effects of Cultivar and Cropping Type on the Growth and Yield of Female and Male Asparagus Plants

Asparagus (Asparagus officinalis L.) is a dioecious perennial plant. Male plants have a higher yield than female plants; therefore, all-male cultivars are more commonly produced. In contrast, female plants have a higher spear weight than that of male plants. To increase profitability, selective cultivation of only female plants would increase the yield of asparagus with a thick spear, which has a higher unit price. However, the effects of cultivar and cropping type on the growth and yield of male and female asparagus plants have rarely been examined. This study compared the growth and yield of female and male plants of three cultivars grown under various cropping types: a rootstock planting forcing culture; a long-term harvest production system in an open field; and a semi-forcing culture. As a measurement of growth, the rootstock weight was significantly higher for female plants compared with that of male plants with the rootstock planting forcing culture. Regarding yield measurements, the spear weight and yield were not significantly different with the rootstock planting forcing culture. However, with the long-term harvest production system in the open field and semi-forcing cultures, the weight and yield of female plants were equivalent to or significantly higher than those of male plants, regardless of the cultivar, except during some harvest periods. These results indicated that the selective production of female plants may be advantageous in terms of growing heavier spears with a higher unit price in a long-term harvest production system in the open field and semi-forcing cultures in Japan. Additionally, the development of a simple and low-cost method for sex identification would be beneficial.

Greenhouse Whitefly and Thrips Management Model Using Natural Enemies in Semi-forcing Culture of Tomato

Greenhouse Whitefly and Thrips Management Model Using Natural Enemies in Semi-forcing Culture of Tomato

Occurrence of Leaf Spot Disease on Asparagus Semi-Forcing Culture Caused by Cercospora asparagi in Hokkaido Prefecture

Occurrence of Leaf Spot Disease on Asparagus Semi-Forcing Culture Caused by <i>Cercospora asparagi </i>in Hokkaido Prefecture

Criteria of Nitrate Concentration in Soil Solution and Leaf Petiole Juice for Fertigation of Cucumber under Greenhouse Cultivation in Gyeonggi region

To develop a technique for efficient management of fertility for cucumber in greenhouse, a quick test method to quantify nitrate (NO₃ - ) content in soil solution and leaf petiole juice using a simple instrument that are easy to use for farmers was investigated. N fertilizer (urea) was applied at 0, 50, 100 and 200% levels of the recommended application rate from 30 days after transplanting to harvest by soil fertigation treatments. Stable results were obtained from analysis of nitrate (NO₃ - ) using top 10 t h or 11 th leaf petioles collected between 10 to 11 am in the morning. Under the semiforcing culture, NO₃ - content of leaf petiole juice was highest at 60 days after transplanting (DAT) at all fertigation treatments. Appropriate NO₃ - content of leaf petiole juice was 2,418±78～2,668±118 at 45 DAT, 3,032±90～3,332±63 at 60 DAT, 2,709±50～3,158±155 at 75 DAT, 2,535±49～2,907±83 at 90 DAT, and 2,242±48 ㎎ L -1 at 105 DAT. In addition, appropriate NO₃ - content of soil solution was 167±9～212±15 at 45 DAT, 83±10～112±12 at 60 DAT, 49±3～92±6 at 75 DAT, 71±9～103±9 at 90 DAT, and 73±9 ㎎ L -1 at 105 DAT. The cucumber yield at 100% N level of fertigation was 7,770 ㎏ 10a -1 and no difference in yield was found at 200% N level of fertigation. However, there was 12% decrease in yield at 50% N fertigation and, 17% decrease at 0% N fertigation. Under retarding culture, NO₃ - concentration of leaf petiole juice was highest at 55 days after transplanting (DAT) at all fertigation treatments. Appropriate NO₃ - content of leaf petiole juice was 2,464±102～2,651±33 at 45 DAT, 3,025±71～3,314±84 at 55 DAT and 2,488±92 ㎎ L-1 at 65 DAT, respectively. Appropriate NO₃ - content of soil solution was 111±10～155±14 at 45 DAT, 93±7～147±14 at 55 DAT, 67±4 ㎎ L -1 at 65 DAT, respectively. The cucumber yield at 50% N fertigation was not different from 1,697 ㎏ 10a -1 of 100% N fertigation level and even with that of the 200% N fertigation. However, there was 21% decrease in yield at 0% N fertigation.

유용미생물(EM) 기비시용 처리가 오이 생육 및 수량에 미치는 영향

This study was aimed to determine the effect of basal application of Effective Microorganisms (EM) on the grow and yield of cucumber. For treatments, the EM was applied to soil with fertilizer composed with N-P2O5-K2O-manure (24.0-16.4-23.8-2,000kg) in the 1.0 strength (defined as EM+1S), 2/3 strength (defined as EM+2/3S), 1/2 strength (defined as EM+1/2S), without fertilizer (defined as EM), or only fertilizer in the 1.0 strength (defined as 1S). In result, there was no significant differences of organic substance content and pH with the EM treatment. While the EC (Electric conductivity) concentration was decreased, plant-available P (phosphorus) was markedly increased. Chlorophyll content was highest in the treatment of EM+standard application rate for both semi-forcing and retarding culture. In contrast, no significant difference was found in plant height and internode length under the fertilizer treatment. Weekly harvested number of cucumber was highest at the treatment of EM+standard application for the semi-forcing culture, while it was 3.6 at the EM+1/2 application for the retarding culture. Weekly yield was greatest at the EM+standard application treatment and decreased with the decrease of fertilizer application rate. In addition, weekly yield was significantly reduced in the treatment of EM . There was no significant difference in yields by production time with the fertilizer applications?. Yield was increased with temperature for the semi-forcing culture, while consistent pattern was maintained for the retarding culture.

Development of a New Melon Cultivar ‘Ibaraking’ with High Fruit Growth Ability under Low Temperature Conditions, High Total Soluble Solid Content, and Resistance to Fusarium Wilt

‘Ibaraking’ is a new F1 melon (Cucumis melo L.) cultivar with green-fleshed fruit, high fruit growth ability under low-temperature conditions, high total soluble solid (TSS) content, and a long shelf life. It was developed from a cross between 2 parental lines P2 and P32 at the Plant Biotechnology Institute, Ibaraki Agricultural Center, Ibaraki, Japan. The parental line, P2, was fixed by self-pollination of a line selected from somaclonal variants of a cultivar ‘Andes,’ while another line, P32, was fixed by self-pollination of a cultivar ‘Earl’s Seine Natsu 2.’ The fruit characteristics of ‘Ibaraking’ were compared with those of the common melon semi-forcing culture cultivars ‘Andes-5’ and ‘Otome,’ from 2005 to 2007, in semi-forcing culture by creeping cultivation. In ‘Ibaraking,’ low-temperature fruit growth ability and external appearance were equal to those of ‘Otome’ and exceeded those of ‘Andes-5,’ while the TSS content was similar to that of ‘Andes-5’ and exceeded that of ‘Otome.’ With regard to shelf life, ‘Ibaraking’ was superior to ‘Otome’ and equal to ‘Andes-5.’ In response to Fusarium wilt of melon, the most severe melon disease, ‘Ibaraking’ demonstrated resistance to races 0 and 2. These responses were identical to those of ‘Andes-5’ and ‘Otome.’ Therefore, we conclude that ‘Ibaraking’ appears a more suitable cultivar in semi-forcing culture by creeping cultivation in Ibaraki prefecture, Japan.

Effects of Different Rootstocks on Fruit Quality of Grafted Pepper (Capsicum annuum L.)

This study was conducted to examine the effect of grafted peppers (Capsicum annuum) on different rootstocks on fruit quality. Three pepper cultivars, 'Nokkwang', 'Saengsaeng Matkkwari', and 'Shinhong' were grafted onto five commercial rootstocks that are known to be resistant to Phytophtora blight. Non-grafted or auto-grafted peppers were used as controls. Grafted plants were grown during two consecutive harvest periods by semi-forcing culture (April to August) and retarding culture (September to March the subsequent year). Full size green fruits were harvested and weighed weekly from June to August (Semi-forcing culture) and from December to March of the subsequent year (Retarding culture). The fruit size, weight, flesh thickness, and firmness were measured every month. Total marketable yield was not significantly influenced by either auto-graft of 'Nokkwang', 'Saengsaeng Matkkwari', and 'Shinhong' of pepper or grafted with the five commercial rootsctocks. By contrast, grafting influenced the apparent fruit quality of peppers. Fruit characteristics differed depending on the rootstock cultivars. However, the fruit characteristics of rootstock did not affect the fruit characteristics of scion grafted onto that rootstock. Fruit characteristics in each treatment differed among harvest time (first, second, and third harvest). Fruit quality parameters were also different as affected by the harvest period. In conclusion, apparent quality and textural property of pepper fruits were influenced by not only grafting with different rootstocks but also by the harvest period and harvest time. Accordingly, rootstock/scion combination, the scion variety and the harvest period must be carefully chosen to get the desired optimal fruit quality.

Effect of Slurry Composting Bio-filtration (SCB) by Subsurface Drip Fertigation on Cucumber (Cucumis sativus L.) Yield and Soil Nitrogen Distribution in Greenhouse

The use of subsurface drip fertigation using slurry composting bio-filtration (SCB) as nitrogen (N) fertilizer source can be beneficial to improve fertilizer management decision. The objective of this study was to evaluate effects of SCB liquid fertilizer by subsurface drip fertigation on cucumber (Cucumis sativus L.) yield and soil nitrogen (N) distribution under greenhouse condition. Cucumber in greenhouse was transplanted on April and Aug in 2012. N sources were SCB and urea. Four N treatments with 3 replications consisted of control (No N fertilizer), SCB 0.5N + Urea 0.5N (50:50 split application), SCB 1.0N, Urea 1.0N. 100% of N recommendation rate from soil testing was denoted as 1.0N. The subsurface drip line and a tensiometer were installed at 30 cm soil depth. An irrigation was automatically started when the tensiometer reading was -15 kPa. The growth of cucumber at 85 days after transplanting was 5% higher in all N treatment than control. Semi-forcing culture produced more fruit yield than retarding culture. Fruit yields were 62.2, 76.3, 76.4, and 75.1 Mg for control, SCB 1.0N, Urea 1.0N, and SCB 0.5N + Urea 0.5N, respectively. Although fruit yields were similar under SCB 1.0N, Urea 1.0N, and SCB 0.5N + Urea 0.5N, 176 kg K can be over applied if cucumber is grown twice a year under SCB 1.0N that may result in K accumulation in soil. N uptake was 172, 209, 213, 207 kg for control, SCB 1.0N, Urea 1.0N, and SCB 0.5N + Urea 0.5N, respectively. N use efficiency was the highest (37%) at SCB 0.5N + Urea 0.5N under semi-forcing culture. Nitrate-N concentration in soil for all N treatments except control in semi-forcing culture was the highest between 15 and 30 cm soil depth at the 85 days after transplanting and between 0 and 15 cm soil depth after cucumber harvest. These results suggested that SCB 0.5N + Urea 0.5N can be used as an alternative N management for cucumber production in greenhouse if K accumulation is concerned.

돈분 액비 관비가 오이의 생육 및 토양화학성에 미치는 영향

This study was conducted to evaluate fertigation effects of pig slurry (PS) and chemical fertilizer (CF) in cucumber by investigating the growth and yield, nutrient content and uptake, nutrient use efficiency, and soil characteristics in greenhouse cultivation. The cropping patterns of cucumber were semi-forcing culture and retarding culture, and the experiment involves four treatments: No fertilizer (NF), and of N application by slurry composting biofiltration liquefied fertilizer (SCBLF), and of N treatment by chemical fertilizer. The difference on the plant height of cucumber between SCBLF and CF treatments was no significant, but fresh weight and dry weight of stem and root were higher in SCBLF treatment. The Ca content of the leaf was lower in the treatments of SCBLF and the K content of the root was lower in the CF treatment. The Ca content of the stem was lowest in the CF treatment and the mineral content of the fruit showed no significant difference. In case of semi-forcing culture, the gross yield was lower in the CF treatment and the yield of unmarketable fruit was lower in the SCBLF treatments. The nutrient use efficiency of cucumber is as follows: K (8.3 ~ 30.9%), N (4.2 ~ 13.0%), P (1.9 ~ 2.0%). The SCBLF treatments showed higher figure in the soil pH than that of the CF treatment, while EC and the content of -N were higher in the CF treatment than the former. The content of exchangeable K was higher in the plot treated with SCBLF, and there were no significant differences in the content of Ca and Mg between the treatments. In conclusion, it is suggested that the application of liquefied manure made from pig slurry may be able to replace the use of chemical fertilizer in nitrogen and potassium.

ZYMV 감염시기가 오이 생육 및 수량에 미치는 영향

본 연구는 시설오이의 ZYMV 감염시기 및 정식기 감염수준이 생육 및 수량에 미치는 영향을 조사하고자 실시하였다. 정식기부터 15일 간격으로 정식 후 75일까지 접종하였을 때 접종시기가 빠를수록 생육이 크게 영향을 받아 만장, 절간장, 엽수가 무처리에 비해 크게 떨어지는 경향을 보였다. 수량도 접종시기가 빠를수록 무처리에 비해 감소율이 높은 경향이었다. 정식기 접종 수준에 따른 정식 20일 후 바이러스 발병율과 수량간의 회귀분석 결과 반촉성작형은 y = <TEX>$9333.1e^{-0.0317x}$</TEX>(<TEX>$R^2$</TEX>= 0.8946), 억제작형은 y = <TEX>$14695e^{-0.0303x}$</TEX>(<TEX>$R^2$</TEX>= 0.8735)의 회귀식을 구할 수 있었다. 또한 최종 수확일로부터 최초 바이러스 발생시기에 따른 수량감소율을 계산하여 최종 수확일까지 잔여일수와 수량감소율간의 회귀분석을 통하여 반촉성작형은 y = 1.0851x - 6.7067(<TEX>$R^2$</TEX>=0.9567), 억제작형은 y = 1.0439x + 2.1321(<TEX>$R^2$</TEX>=0.9674)의 회귀식을 산정하였다. We investigated the effect of the infection times and infection degrees at transplanting time of Zucchini yellow mosaic virus (ZYMV) on the growth and yield of cucumber plants at the semi-forcing and the retarding culture in 2007. When cucumber was inoculated with ZYMV at transplanting time, 15, 30, 45, 60, and 75 days after transplanting, vine length, internode length, number of leaf of the plants and marketable yield largely decreased as the cucumber infected earlier. The regression models were obtained between the disease incidence levels at 20 days after transplanting as the inoculation degrees and the marketable yield of cucumber: y = <TEX>$9333.1e^{-0.0317x}$</TEX> (<TEX>$R^2$</TEX> = 0.8946) at the semi-forcing culture and y = <TEX>$14695e^{-0.0303x}$</TEX> (<TEX>$R^2$</TEX> = 0.8735) at the retarding culture. And the cucumber yield loss regression models between the symptoms incidence days from the final harvesting time and the rates of yield decrease were expressed as y=1.0851x - 6.7067 (<TEX>$R^2$</TEX> = 0.9567) at the semi-forcing culture andy=1.0439x + 2.1321 (<TEX>$R^2$</TEX> = 0.9674) at the retarding culture.

EVALUATION OF WOOD STRAWBERRY (FRAGARIA VESCA) PRODUCTIVITY

Information about a suitable cropping system and environmental conditions is necessary to grow Fragaria vesca plants for commercial production. This research was conducted to evaluate the growth and productivity of everbearing F. vesca cultivars grown under a forcing culture, semi-forcing culture, and late semi-forcing culture. Results showed that the mean growth rate of the cultivars in the forcing culture was the lowest among these cropping systems. Significant differences were found in the number of harvested fruits, the fruit weight per plant, and the total soluble solids (TSS) among the cultivars in all cropping systems. The number of harvested fruits, the fruit weight per plant, and the total soluble solids were highest for 'Alba' in all cropping systems. Furthermore, significant correlation was identified between the inflorescences per plant and branch numbers per plant (r=0.77) and between the number of harvested fruits per plant and the fruit weight per plant (r=0.977).

SELECTIVE BREEDING RESEARCH OF NEW STRAWBERRY CULTIVARS 'SHIMEI 5'

'Shimei 5' a new strawberry cultivar, derived from the cross 'Y95' × 'New Star' made in 2001, 'Y95' was a fine variety which was introduced from Israel and 'New Star' was bred by the Shijiazhuang Pomology Institute. 'Shimei 5' has conical or flat conical, bright red and shiny fruit, average weight of the primary fruit is 38.8 g, average weight of the secondary fruit is 25.3 g, weight of the biggest fruit is 67 g, fruit is uniform and tidy; fruit flesh is red, the texture is dense and flesh is thin, fiber is low, pith is bigger with no cavity, the fruit has medium juicy, fragrance is intense, fruit has good flavour, the soluble solid content is 8.83%, quality is excellent, fruit elastic force is 0.906 kg/cm 2 , fruit flesh resistance is 0.525 kg/cm , firmness is high, consequently storage and transportation is good; high yield, disease-resistant, dormancy period is short. It is suitable for dew place culture and semi-forcing culture.

JUDGMENT INDEX AND INHERITANCE OF CHILLING REQUIREMENT TO BREAK DORMANCY IN STRAWBERRY

Strawberry cropping systems adapted to each district from the southern to northern parts of Japan were developed together with advancing of studies on ecotype characteristics of various cultivars and techniques of controlling flower induction and dormancy, resulting in many cropping systems. The cultivars adapted to forcing culture have shallow dormancy and those adapted to semi-forcing culture and open culture have deep dormancy. This experiment was carried out to determine a judgment index for the chilling requirement to break dormancy and to investigate the inheritance of dormancy in strawberry plants. Runner plants of 8 varieties with various chilling requirements to break dormancy were exposed to varying degrees of chilling under 5°C. Runnering was a more effective index than the sudden extension of petiole length. Moreover, the cessation of continuous flowering under the minimum temperature of 15°C with a 16h photoperiod was used to judge the chilling requirements to break dormancy because the coefficient of variation of runnering was smaller than that of the sudden extension of petiole length and the cessation of continuous flowering. Chilling requirements and the cumulative hours of chilling to break dormancy of the runner plants were longest, while that of the over-wintered seedlings was longer than that of the annual seedlings. Runner plants of the selfed seedlings and the crosses between seedlings of a shallow dormancy variety 'Nyoho' and deep dormancy varieties 'Aiko' and 'Pajaro' were used to investigated the inheritance of dormancy. The degrees of dormancy of the crossed seedlings were tend aside of parents with shallow dormancy. It seems that the selection of strawberry plants with deep dormancy needed the use of many seedlings.

시설하우스내 수박 재배 작기별 작기별 해충 발생소장

전북 고창의 시설하우스에서 수박 재배 작기에 따른 해충의 시기별 발생 밀도를 2006년부터 2007년 까지 조사하였다. 촉성재배에서 발생되는 주요 해충은 목화진딧물이었으며, 다발생기는 3월 중순과 4월 하순이었다. 반촉성재배에서 발생되는 주요 해충은 목화진딧물과 응애류(점박이응애+차응애) 이었으며, 다발생시기는 6월 이었다. 억제재배에서는 목화진딧물, 응애류(점박이응애+차응애), 아메리카 잎굴파리, 목화바둑명나방의 발생과 피해가 많았다. 목화진딧물과 응애류는 9월에 발생량이 많았다. 아메리카잎굴파리는 9월 상순에 발생량이 많았다. 목화바둑명나방은 8월 중순부터 피해가 나타났으며, 9월 중순에 피해엽률이 79.4%로 가장 큰 피해를 주었다. The seasonal occurrence of insect pests in watermelon cultivated in greenhouses was surveyed in Gochang from 2006 to 2007 considering three seasonal types of culture: forcing culture, semi-forcing culture and retarding culture. Aphis gossypii, mites (Tetranychus urticae+T. kanzawai) and Palpita indica were the most serious pest species in watermelon greenhouse culture. A. gossypii and mites showed high density during the months of June and September in semi-forcing and retarding culture, respectively. Palpita indica was observed only in retarding culture. Leaf damage by Palpita indica was observed from the middle of August and peaked to 79.4% damage in the middle of September. Thrips and whiteflies were captured in high density by the yellow sticky trap in semi-forcing culture and retarding culture but these insects showed low population density in watermelon leaves.

전남지역의 호박에 발생하는 바이러스 병 발생 실태

전라남도 호박 주산단지의 2000년 바이러스병 발생포장율은 노지재배 76.1%,억제재배 55%,반촉성재배는 발생이 없었으며, 포장별 이병주율은 반촉성재배 3.6%, 노지재배 100%이었다. 포장에서 채집된 시료에 대한 RT-PCR 검정결과 노지재배는 40점 시료 중 WMV 16점, ZYMV 10점, PRSV 2점이 각각 검출되었으며, WMV, ZYMV, PRSV의 2개 또는 3개 바이러스에 중복감염된 시료도 7점이었다. 억제재배는 21점 시료중 WMV 7점, ZYMV 6점, PRSV 6점, WMV와 PRSV의 2개 바이러스에 중복감염된 시료가 1점이었으며, CMV는 검출되지 않았다. Field disease incidences of squash virus diseases in Jeonnam province were estimated to be 76.1% and of delayed planting on August-September (retarding culture) and on February-March (semi-forcing culture) on glass house were 55.0% and 0%, respectively, in 2000. Disease incidences of individual squash plant within a field were 100% and 3.6%, respectively, in wild culture and retarding culture. Total of 61 samples suspected to be infected with viruses were collected in 2000 and tested by RT-PCR using specific oligonulceotide primer sets designed for the detection of Cucumber green mottle mosaic virus (CGMMV), Kyuri green mottle mosaic virus (KGMMV), Zucchini yellow mosaic virus (ZYMV), Papaya ring spot virus (PRSV), Watermelon mosaic virus (WMV), and Cucumber mosaic virus (CMV). Each specific primer set for WMV, ZYMV, and PRSV amplified expected size of DNA fragments from 16, 10, and 2 samples in wild culture, respectively. Double or triple infection were observed in 7 samples tested. In contrast, each specific primer set for WMV, ZYMV, and PRSV confirmed virus infection from 7, 6, and 6 samples, respectively, in samples collected from semi-forcing culture. Double infection of WMV and PRSV was observed in only one sample. However, no DNA fragment was amplified from RT-PCR using CGMMV, KGMMV, and CMV specific oligonucleotide primer sets indicating no CGMMV, KGMMV, or CMV infection in squash fields in Jeonnam province in 2000.

寒冷地の半促成栽培および露地栽培におけるイチゴ黒斑病抵抗性系統Ｍ１６‐ＡＲ１，２および３の適応性

Adaptability of Alternaria black spot-resistant strawberry lines, M 16-AR 1, 2 and 3 selected from calliclones derived from the shoot apex tissues of 'Morioka-16', to the semiforcing culture and open field culture in the cool region of Japan was examined.To adapt these lines to a semi-forcing culture, the chilling requirement of 1, 400 hr at or below 5 °C for 'Morioka-16' was used as a standard. In open field culture, they were grown according to the conventional methods. No significant differences in vegetative and fruit characteristics such as plant height, length of petiole, number of runners, sweetness (Brix), acidity, puncture resistance by fruit skin and crop yield, were found between 'M 16-AR' lines and 'Morioka-16'.We found 'M 16-AR 1, 2, and 3' suitable for semi-forcing culture and open field culture, so that these lines can replace 'Morioka-16' which is susceptible to Alternaria black spot. 'M 16-AR 2' was registered on 1 September 1992, as 'AKITA BERRY', a new strawberry cultivar.

サトイモ培養球茎の生育特性の品種間差異と早熟栽培への利用

サトイモ品種群の代表的な5品種•系統を供試し,その培養球茎株と慣行球茎株の特性を比較した。また,'石川早生'の培養球茎を用いたハウス, トンネルによる早熟栽培における生育特性を調査し, 培養球茎を利用した栽培の実用化について検討した。1.各品種, 系統ともに培養球茎株は慣行球茎株に比べて地上部の生育は劣るが地下部球茎の肥大は良く,植物体全体に占める球茎の割合が大であった。2.子芋利用品種'烏播', '土垂', '早生小蓮葉芋', '石川早生'では子芋, 孫芋の着生数が増加して1個当たりの重量は小さくなる傾向があった。3.親芋利用型の変異系統では培養球茎株は親芋の肥大が良かった。子芋利用品種では親芋は小さくなり,利用部位である子芋, 孫芋の割合が大きかった。4.'石川早生'ではハウス栽培, トンネル栽培でも培養球茎株の生育特性は露地栽培と同様の傾向が認められた。5.培養球茎株は慣行球茎株に比べ地上部の枯れ込みが早くから開始され, 子芋, 孫芋の肥大は早くなることが認められた。6.早生品種を用いたハウス, トンネルによる早掘り栽培で培養球茎を直接利用した栽培の実用化の可能性が示された。

Studies on tomato wilt in semiforcing culture

Studies on tomato wilt in semiforcing culture