Stomatal pore is an important physiological trait that is closely linked to photosynthesis and transpiration as carbon dioxide and water vapor move through it between the atmosphere and plants. The present study investigated stomatal traits, such as stomatal density, index and size, of herbaceous native and alien plant species living in a riparian park on the Nakdong River to understand how those traits vary and to know if successful settlement of alien plants is attributed to those traits. There was no difference in stomatal density, index and size between native and alien plants with kidney-shaped stomata, suggesting that an empty ecological niche is not an essential prerequisite for the successful settlement of alien plants. Stomatal density showed a negative correlation with leaf thickness and leaf dry weight content (LMDC), but there was no correlation with Specific leaf area (SLA). All plants with kidney-shaped stomata had amphistomatous leaves, and the density and size of dumbell-shaped stomata were lower than those of kidney-shaped stomata.
The two main hypotheses that explain why invasive alien plants successfully colonize new environments are: 1) invasive alien plants are functionally different from native plants in a community, and 2) the plants can adapt well to new environments because they are functionally similar to native plants. The present study investigated the functional traits of naturalized alien herbaceous plants and their native neighbors in a riparian park area near the Hapcheon-Changyeong weir along the Nakdong River to determine which of the two hypotheses applied to the study area. According to the results, leaf functional traits, such as leaf area, specific leaf area, leaf thickness, leaf dry matter content, leaf nitrogen content, and leaf carbon content differed between naturalized alien and native plants, which could be attributed to the higher leaf nitrogen contents in naturalized alien plants than in native plants. The high leaf nitrogen contents are associated with high photosynthetic rates, which lead to effective resource use and rapid growth; therefore, naturalized alien plants growing in the study area were considered to have such functional traits. The results of the present study support the hypothesis that the successful establishment of invasive alien plants is attributed to the functional trait differences between invasive and native plants.
A diverse group of plant-growth promoting bacteria were isolated in button mushroom (Agaricus bisporus) media to investigate the plant-growth promoting traits of compounds including indole acetic acid (IAA), ammonia, 1-aminocyclopropane-1- carboxylic acid deaminase, siderophore, and hydrogen cyanide. Twenty-one bacterial strains showing positive effects for all the test traits were selected and classified to confirm bacterial diversity in the media habitat. Plant-growth promoting traits of the isolates were also assessed. All strains produced IAA ranging from 20 μg/mL to 250 μg/mL. Most of the isolates produced more than 80% siderophore. Four strains (Pantoea sp., PSB-08, Bacillus sp., PSB-13, Pseudomonas sp., PSB-17, and Enterobacter sp., PSB-21) showed outstanding performances for all the tested traits. In a bioassay of these four strains using mung bean plant, the best growth performances (23.16 cm, 22.98 cm, 2.27 g/plant, and 1.83 g/plant for shoot length, root length, shoot dry weight, and root dry weight, respectively) were obtained from the plants co-inoculated with Bacillus sp., PSB-13. The resultant data indicate that button mushroom media have got a diverse group of bacteria with plant growth promoting abilities. Thus, the media could be a good recycling resource for using to an effective bio-fertilizer.
This experiment was conducted to elucidate the relation-ship between vertical distribution of rice roots and yield traits under field conditions. Eight IRRI's new plant type rices (NPTRs) were tested in a volcanic ash soil paddy field under dense (IO 10 cm) and common (20 20 cm) planting densities. These lines were evaluated to have more spikelet numbers per panicle (SNP), lower filled grain rate (FGR), and lower rough grain weight per hill (RGWH). In dense planting, rough grain weight per stem (RGWS) was increased due to heavier culm and leaf dry weight (CLDW), and both RGWS and CLDW were related with the percentage of root distribution (%RWI) in the 10~30 cm soil layer, while in common planting, RGWS was not closely related with CLDW. SNP was highly related with root dry weight (RDW) in the 0~10cm soil layer. FGR was mainly affected by ROW in the 10~30 cm soil layer under both planting densities. RGWS was positively correlated with top dry weight (TDW) and harvest index (HI), and TDW was positively correlated with RWI under common planting or %RWI under dense planting, and HI was positively correlated with RWI in the 10~30 cm soil layer only under dense planting. RGWS was closely related with root weight index by dry weight (RWI) in the 10~30 cm soil layer and %RWI in the 0~30 cm or 10~30 cm soil layer under dense planting, and with only RWI in the 10~30 cm soil layer under common planting. But RGWH showed the close positive relationship with RDW and RWI in the 10~30 cm soil layer under dense planting, while under common planting, it showed the close positive relationship with RWI and %RWI in the 10~30 cm soil layer or %RWI in the 0~30 cm soil layer. The deeper root system in rice, especially under dense planting, is important for high yield of NPTRs focusing on the increment of top mass production and harvest index.
듀럼밀(Triticum durum var. hordeiforme 2n=28 AABB)에서 trisomics(2n=28+1)을 육성하여 외부형태적 형질에 발현되는 양적효과를 조사하였다. Trisomics은 각각의 잉여염색체에 존재하는 유전자의 상호작용에 의해서 외부형태적 형질에 정상식물과 명백히 상이한 양적효과를 나타내었다. 그러나 A및 B의 양 genome에 속하는 동조염색체간에는 서로 유사한 특성을 나타내어 상호 구별짓기가 매우 어려웠다. 이와 같은 현상으로 부터 몇몇의 외부형질에 관여하는 주동유전자의 염색체위치는 동조염색체상에 존재하고 있음이 시사되었으며, 이들은 같은 역할을 하는 동조유전자인 것으로 밝혀졌다. 따라서 듀럼밀의 동조성 및 연관군이 동시에 해명된 것으로 보여지며, 본 trisomics은 밀속의 A및 B genome의 각각의 염색체에 관한 유전분석 및 유전자지도 작성을 위한 연구재료로서 유익할 것이다. 또한 빵밀(Triticum aesitivum AABBDD)의 선조종인 듀럼밀(T. durum AABB)과 타루호밀(T. squarrosa DD)의 진화과정 및 비교유전분석상 매우 중요한 소재로서 이용될 것이다.
보리의 월동전 초형에 따른 농업형질의 차이를 비교하고저 같은 교배조합에서 선발, 고정시킨 계통 및 교배친 10개를 공시하여 분석한 결과는 다음과 같다. 1. 포복형에 비해서 직립형 계통은 출수기 및 성숙기가 빠르고, 간장은 컸으나 m2 당 수수, 수량성은 적었다. 또한 천입중, 정입률, 광투과율은 컸다. 2. 출수기는 성숙기, 수량과 정상관, 간장, 천입중, 정입률, 광투과율과 부상관이 있었다. 수량은 광투과율과 부상관이 인정되었다. 3. 월동전에 초형이 포복형이면서, 월동후 생육재생기가 빠르고 식간신장이 빠른 계통을 육성, 선발하는 것이 특히 내한성이 요구되는 지역에서 유리할 것으로 생각된다.