• Journal of Ecology and Environment
• /
• 제34권3호
• /
• pp.295-305
• /
• 2011

Many studies have suggested the positive effects of grazing by large herbivorous mammals on seed dispersal, but little is known about how herbivores could affect the fate of ingested seeds. This study examined the effects of seed ingestion by sika deer (Cervus nippon) on seed fate in a temperate grassland established in an urban park long resided by high densities of sika deer. I compared species composition and seasonal traits of seed abundance and maturity in the grassland community with those in deer fecal pellets. In total, 27 herbaceous species were observed, including the predominant Zoysia japonica. Seed phenology and production differed among the three dominant species (Z. japonica, Digitaria violascens, and Hydrocotyle maritima). Pellets contained at least 26 species of herbaceous seeds, and their abundance differed among species. Of the 26 species, 15 were observed in the vegetation at the study site. The peak of seed abundance in pellets for the dominant species appeared 1 month after the peak of inflorescence production (but most of the inflorescences were immature and susceptible to digestion) and consequently corresponded to the peak of mature inflorescence. Because sika deer are likely to ingest seeds at any maturity stage in the grassland and immature seeds are less hardened, ingested immature seeds can suffer great losses. The results suggested that the survival of germable seeds with great losses of immature seeds may be a factor determining which plant species can be successfully dispersed by herbivores.

• Plant Resources
• /
• 제8권1호
• /
• pp.13-16
• /
• 2005

This study was conducted to develop effective production system in greenhouse for leaves and stems of Angelica acutiloba by fertilizing of Sta-Green in pots. The results obtained are summarized as follows. Germination rate of Angelica acutiloba seeds collected in 2003 was $13\%$, while germination rate of seeds Collected in 2004 was above $91\%$. Seed germination rate and plant biomass of Angelica acutiloba collected in 2004 were higher than seed gathering in 2003. Especially, plant growth and yield of Angelica acutiloba grown in pot(The pots was filled with soil mixtures of Sta-Green and Peat Moss mixed with 45:55 ratio.) was the highest. These results indicate that leaf and stem production of Angelica acutiloba can be improved by fertilizing of Sta-Green in pots and optimizing seed collecting time in greenhouse.

• 한국작물학회지
• /
• 제48권6호
• /
• pp.424-428
• /
• 2003

옥수수 신품종 찰옥2호의 안정적인 $\textrm{F}_1$ 종자 생산에 적합한 채종 재배법을 구명하고자 1998-2000년 3년간 시험을 수행하였던 바 그 결과는 다음과 같다. 1. 찰옥2호의 KW7/KW3교배조합은 KW7의 수임능력 부족과 KW3의 화분비산거리가 짧아서 $\textrm{F}_1$종자 생산량이 적다. 2. 찰옥2호의 $\textrm{F}_1$ 종자 생산은 KW3/KW7 조합으로 하고 KW7에 비닐피복하여 모$.$부본을 동시에 파종하며, 재식비율 4:1로 파종하는 것이 가장 효과적이었다. 3. 찰옥2호의 KW3/KW7 교배조합은 KW3의 부패립 발생이 문제가 된다. 따라서 종자의 품질저하 방지와 발아율을 고려하여 출사후 35일에 수확하는 것이 바람직하였다.

• 한국잡초학회지
• /
• 제32권1호
• /
• pp.17-24
• /
• 2012

The study was conducted to investigate the effect of weed interference and starter fertilizer on subsequent soybean seed quality at the Agricultural Research Farm and Laboratory of Razi University, Kermanshah, Iran. Two factorial experiment was laid-outon a randomized complete block design with four replications. First factor was starter fertilizer levels (0 and 25 kg $ha^{-1}$) applied in the forms of monoammonium phosphate, the second factor was different weed interference periods consisted of five initial weed-free periods (in which, plots were kept free of weeds for 0, 15, 30, 45 and 60 days after crop emergence (DAE) and then weeds were allowed to grow until harvest) and five initial weed-infested periods (in which, weeds were allowed to grow for 0, 15, 30, 45 and 60DAE, after which the plots were kept free of weeds until harvest). Full season weedy condition reduced 100-seed weight, seed germination percentage and seedling dry weight by 25.9, 13.3 and 22.5%, respectively and increased mean germination time and seed electrical conductivity by 55.8 and 24.3%, respectively as compared with full season weed-free control. However, the traits under study were not significantly influenced when field was kept free of weeds for at least 45 DAE (R1) or weedy condition was continued for less than 30 DAE (V8). There was a significant and negative correlation between weed biomass and seed weight (r = -0.93), so that when weed free condition was less than 45 DAE or weed infested period was continued for at least 30 DAE, soybean plants produced wrinkled and underdeveloped seeds with lower weights and qualities. Moreover, soybean seed quality reduction due to weed interference was more evident when starter fertilizer was applied and weeds interfered with soybean from the beginning of the growing season. Information from the present study is beneficial in soybean seed production systems and where farmers use the harvested seeds for the following planting.

• 식물조직배양학회지
• /
• 제24권4호
• /
• pp.239-256
• /
• 1997

Plants belonging to the category of 2n apomixis or agamospermy form embryos and seeds without the processes of normal meiosis and syngamy. Seeds produced in this way have identical genotype of their maternal parent. Three different types of agamospermy are recognized: diplospory, apospory, and adventitious (adventive) embryony. $F_1$ hybrid cultivars cannot be used as seed sources in the next ($F_2$) generation because this generation would be extremely variable as a result of genetic segregation. Hybrid vigor is also reduced in the $F_2$ generation. Therefore, parental stocks for hybrid seed production need to be maintained and cross must be continuously repeated. Agamospermic 2n apomixis would make it possible to fix the genotype of a superior variety so that clonal seeds faithfully representing that genotype could be continuously and cheaply produced independent of pollination. That is, $F_1$ hybrid seeds could be produced for many generations without loss of vigor or genotype alteration. Production of apomictic $F_1$ hybrid seed would be simplified because line isolation would not be necessary to produce seed or to maintain parental lines, and the use of male-sterile lines could be avoided. Overall, apomixis would enable a significant reduction in hybrid seed production costs. Additionally, the production of clonal seed is not only important for seed propagated crops, but also for the propagation of heterozygous fruit trees and timbers. Clonal seed would help avoid costly and time-consuming vegetative propagating methods that are currently used to ensure the large-scale production of these plants. Apomixis is scattered throughout the plant kingdom, but few important agricultural crops possess this trait Therefore, most research to date has centered on introgressing the trait of apomixis into agricultural crops such as wheat, maize, and some forage grasses from wild distant relatives by traditional cross breeding. The classical breeding approach, however is slow and often impeded by many breeding barriers. These problems could be surmounted by taking mutagenesis or molecular approach. Arabidopsis thaliana is a tiny sexually reproducing plant and is convenient in constructing and screening in molecular researches. Male-sterile mutants of Arabidopsis are particularly suitable genetic background for mutagenesis and screening for apomictic mutants. Molecular approaches towards isolating the genes controlling the apomictic process are feasible. Direct isolation of genes conferring apomixis development would greatly facilitate the transfer of this trait to wide variety of crops. Such studies are now in progress.

• 한국약용작물학회지
• /
• 제24권3호
• /
• pp.207-213
• /
• 2016

Background: This study aimed to investigate the flowering and fruits formation characteristics of Korean Panax ginseng varieties. The results will provide basic data for ginseng seed production and breeding program. Methods and Results: The characteristics investigated included flowering date, seed setting rate, seed type and seed production. The ginseng variety Chungsun had the earliest emergency and flowering dates, whereas Sunhyang showed late emergence and flowering dates. The emergence date of Chunpoong was not later than that of the other varieties, but the flowering date was delayed. The seed setting rate was 64.6%, 75.8%, 78.5% and 74.4% for three, four, five and six-year-old varieties, respectively. The ratio of double seed (RD) for Sunhyang and Chungsun were higher than those for the others, whereas the RD for Chunpoong was the lowest. Yunpoong and Sunone had many stems per plant and a high seed production rate. Seed production was 21.7, 67.7, 74.4 and 89.0kg/10 a in three, four, five and six-year-old varieties, respectively. Conclusions: The emergence date ranged from April 15 to 25, and the flowering date was from May 10 to the 19 for the new ginseng varieties. The average seed multiplication of the ginseng varieties was about 8.5 and 21.1 times a year for varieties in which, seed-production occurs once a year for over four years and four times over six years, respectively.

• Journal of Biosystems Engineering
• /
• 제27권5호
• /
• pp.381-390
• /
• 2002

Direct seeding of rice-seed pellets is expected to be an alternative for solving problems in current direct seeding cultivation of rice. but mass production of rice-seed pellets is prerequisite for practical application. Design. construction and performance evaluation of an experimental rice seed pelleting machine were carried out for mass production of rice-seed pellets. The pelleting machine intended to make a ball type rice-seed pellet, which have 3∼5 rice seeds and diameter of which is 12 mm. Pellet materials ; rice seeds, soil, and binder were mixed and kneaded by the mixer. The designed rice seed pelleting machine fed pellet materials by screw conveyor to forming rolls and made rice-seed pellets. Capacity, ratio of perfect rice-seed pellets, seed and pellet material loss were investigated as mixing ratio of soil to rice seed and feeding rate of pellet materials. The pelleting machine showed up to 37,000 pellets/h of pelleting rate, 61∼71% of weight ratio of perfect rice-seed pellets to pellet materials supplied, 17∼48% of seed loss ratio. Average weight and average diameter of the pellets were 1.66 g and 12.0 mm. respectively. More than 3 rice seeds were included in most pellets at 6 : 1 of mixing ratio of soil to rice seed. And compression strength of the pellets was in the range of 88-130 N. To improve performance of the pelleting machine, improvements of the forming rolls, feeding mechanism, and discharging mechanism for reducing loss of pellet materials and seeds damage are needed.

• 한국작물학회지
• /
• 제40권1호
• /
• pp.44-51
• /
• 1995

도입에 의존하고 있는 풋콩 종자 생산체계를 확립하고자 조숙성 품종인 큰올콩과 풋콩 도입풍종인 Fukura 피두를 평야지（영남농업시험장） 및 고랭지（경남 밀양군, 사자평 ：해발 850m）에 파종시기（5월 15일, 6월 15일, 7월 15일）를 달리하여 생육 및 수량과 병해립 및 저장후 발아력을 조사한 결과를 요약하면 다음과 같다. 1. 파종시기가 빠를수록 협수가 많고 100립종은 무거웠으며 수량도 높았다. 재배지별로는 평야지가 고랭지보다 증수되었고, 큰올콩이 Fukura보다 수량성이 높았다. 2. 남부지방의 산간 고랭지는 평야지에 비해 생육 및 100립종이 저하하고 수량성이 크게 떨어져 평야지보다 불리하였다. 3. 안전립 수량은 파종시기가 빠를수록 높고, 평야지 및 큰올콩품종에서 증수되었으며, 전체 립종에 대한 안전립 비율은 고랭지에서 높게 나타났다. 4. 파종시기에 따른 병해정도는 큰올콩은 뚜렷한 차이가 없었으나 Fukura는 파종기가 빠를수록 나병립율이 높았고, 미이라병은 파종기가 빠를수록 심하게 발생하였으며 자정병은 파종기가 늦을수록 많이 발생하는 경향이었다. 5. 종자의 발아율은 파종기가 늦은 것이 높았으며, 5월 15일에 파종하여 수확ㆍ저장한 종자의 발아율은 매우 낮아 문제시 되었다. 따라서 풋콩 종자생육을 위한 적정파종시기는 수파기의 고온ㆍ다습한 환경을 고려하여 6월 중순경이 좋을것으로 생각되었다.

• Bulletin of the Korean Chemical Society
• /
• 제35권7호
• /
• pp.2172-2174
• /
• 2014

• 한국작물학회지
• /
• 제31권1호
• /
• pp.19-23
• /
• 1986

27개 농가포장에서 인삼종자의 생산량 및 종자소질을 조사하였던 바, 그 결과를 요약하면 다음과 같다. 1. 포장별 채종량은 거의가 4~10$\ell$/간(간 : 180x90cm의 면적) 절위이였다. 2. 채종량이 많은 포장의 종자일수록 100입중, 4mm이하의 종자 생산 비율이 모두 낮아지는 경향이었다. 3. 전종자의 12%는 4mm이하의 종자이었으며 66%는 4-5mm, 22%는 5mm이하의 종자이었다. 4. 채종모본 선정 포장에서는 방임채종포에 비해 채종량은 감소되었으나 100입중, 4mm이하 종자의 생산비율은 오히려 증가되었다. 5. 종자의 길이와 폭 간에는 정(＋)상관이 인정되었으나 폭과 두께, 길이와 두께간에는 유의상관 인정되지 않았다. 6. 채종량은 채종모본의 생육상태에 따라 차이가 있었으나 4mm이하의 종자생산 비율을 감안할 때 100간당 7-8$\ell$ 미만 채종하는 것이 좋을 것으로 보여졌다.