Developmental aspects of tristyly in Lythrum salicaria

1998 ◽  
Vol 76 (7) ◽  
pp. 1214-1226 ◽  
Author(s):  
Tarun K Mal

The developmental basis of floral polymorphism was investigated in the tristylous invasive species, Lythrum salicaria L. (Lythraceae). In tristylous species, the stigmas are positioned above (in the long morph), below (in the short morph), or between (in the mid morph) the outer and inner staminal whorls. Flower samples were collected at three different growth stages (early, pre-anthesis, and post-anthesis) from three genotypes from each of the three morphs to observe morph-specific differences in growth patterns of filaments and styles and their constituent epidermal cells. From each flower, I measured the length of styles and two types of stamens and their epidermal cells at the basal, intermediate, and apical regions of each organ. Differentiation of organ levels begins at a very early stage. Growth rate of the long pistil is higher than in the mid pistil followed by the short pistil. However, the growth rate of epidermal cells is higher in the short style followed by the mid and long styles. The number of cells does not increase during style development in the short morph but does increase in the long and mid morphs. Although the relative growth of the outer stamens is greater than in the inner stamens in all three morphs, the relative cell size is greater in the inner stamens than in the outer stamens. Cell size differs between outer and inner stamens in the long and mid morphs but not in the short morph. The intermediate cells are larger compared with the basal and apical cells of the stamens and styles. The number of epidermal cells increases in the outer stamens during development, whereas it remains constant in the inner stamens of the mid morph and increases only slightly in the inner stamens of long morph.Key words: floral development, growth and division of epidermal cells, heterostyly, purple loosestrife, style and stamen growth, style-stamen polymorphism.

Author(s):  
А.И. Новиков

Выбор механизированной технологии сепарации семян сосны обыкновенной зависит от наибольшей вероятности получения положительного результата при онтогенезе на ранней стадии. Исследований, содержащих сведения о росте и развитии сеянцев, полученных из семян, одновременно сепарированных по цвету и размеру, достаточно мало. Объектом наблюдения послужила технология сепарации, а предметом сеянцы сосны обыкновенной в течение первого вегетационного периода в открытом грунте. Сеянцы получены по контейнерной технологии из семян, сепарированных на стандартном оптическом сепараторе на три группы, а затем каждая цветосеменная группа разделена на стандартном решетном сепараторе еще на две размерные группы с использованием решет с круглыми отверстиями 2,5 и 3,5 мм. Ротация сеянцев, включая высев и агротехнический уход, проведена на стандартном оборудовании Воронежского лесного селекционносеменоводческого центра в период с мая по октябрь 2017 года. Полученные сеянцы шести цветоразмерных групп сразу высаживали под меч Колесова в дно борозды на испытательном участке. Участок расположен на пирогенно нарушенных землях Левобережного лесничества Учебноопытного лесхоза Воронежского государственного лесотехнического университета им. Г.Ф. Морозова. На первом ювенильном этапе 2018 г. контролировали высоту и приживаемость сеянцев с мая по сентябрь периодичностью один раз в 33 34 сут. Результаты обрабатывали методами биометрического анализа. Вычисляли относительную скорость роста сеянцев, а также асимметрию и эксцесс распределения вариант высот. Установлено, что при проектировании устройств для экспрессанализа и сортировки семян и разработке алгоритма процесса предпосевной обработки необходимо учитывать влияние как качественных, так и количественных параметров. Например, для аэросева статистически значимо сепарировать крупные темные семена, сеянцы из которых обладают высокими значениями относительной скорости роста и приживаемости. Для обеспечения оптимальной площади питания и классификации для производства контейнерных сеянцев статистически значимо сепарировать светлые крупные и темные мелкие, как дающие сеянцы с максимальной и минимальной высотами соответственно. Результаты исследования в определенной степени согласуются с ранее известными данными об онтогенезе сосны обыкновенной, уточняя их на стадии предпосевной подготовки особенностями влияния одновременной сепарации семян по спектрометрическим и размерным признакам на рост и развитие сеянцев. Следует отметить, что остается множество вопросов, требующих дополнительных изысканий: остается ли характер распределения параметров сеянцев постоянным на последующих стадиях онтогенеза или полученные данные имеют единичный характер Не является ли изменчивость фактора высоты сеянцев результатом влияния только внешних факторов Нарушается ли генетическое разнообразие репродуктивного материала при такой технологии The choice of mechanized technology of Scots pine seeds grading is depends on the highest probability of obtaining a positive result at an early stage ontogenesis. However, very little information about seedlings growth and relative growth rate from seeds simultaneously graded by color and size. The object of observation was the seeds grading technology, and the subject Scots pine seedlings during the first growing season on the open ground site. Seeds graded by standard optical separator into three color groups and then each group graded by standard screen separator into two size groups using a sieve with round holes of 2.5 and 3.5 mm. The rotation of container grown Scots pine (Pinus sylvestris L.) seedlings, including planting and cultural care, carried out on standard equipment of the Voronezh forest selection seedgrowing centre in the period from may to October 2017. The resulting containergrown seedlings of six groups were immediately planted under the sword of Kolesov in the bottom of the furrow on the test site. The site is located on the pyrogenic disturbed lands of the leftBank forestry of the educational and experimental forestry of the Voronezh State University of Forestry and Technologies named after G.F. Morozov. At the first juvenile stage of 2018, the height and survival of seedlings were controlled from may to September, once every 33 34 days. The results were processed by biometric analysis. The relative growth rate of seedlings was calculated, as well as the asymmetry and kurtosis of the height distribution. It is established that the design of devices for rapid analysis and sorting of seeds and the development of the algorithm of pretreatment process must take into account the influence of both qualitative and quantitative parameters. For example, it is statistically significant to separate large dark seeds for aerial seeding, the seedlings of which have high values of the relative growth rate and survival rate. In order to provide optimal feeding area and classification for container seedling production, it is statistically significant to separate light large and dark small as giving seedlings with maximum and minimum heights, respectively. The results of the study are to some extent consistent with the previously known data on the ontogenesis of Scots pine, specifying them at the stage of presowing preparation features of the effect of simultaneous separation of seeds by spectrometric and dimensional characteristics on the growth and development of seedlings. It should be noted that there are many questions that require additional research: whether the nature of the distribution of the parameters of seedlings remains constant in the subsequent stages of ontogenesis or the data obtained Is the variability of the seedling height factor a result of the influence of external factors only Is the genetic diversity of reproductive material impaired by this technology


Forests ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 1120
Author(s):  
Xiao-Long Bai ◽  
Yun-Bing Zhang ◽  
Qi Liu ◽  
Yang-Si-Ding Wang ◽  
Da Yang ◽  
...  

There is accumulating evidence that the abundance and biomass of lianas are increasing with global climate change in the Neotropics. However, our knowledge of growth–trait relationships among lianas is surprisingly rare. Here, we monitored the relative growth rate of 2860 individuals from seven deciduous and four evergreen liana species in a 20 ha subtropical cloud forest dynamics plot at high elevation (2472–2628 m a.s.l.) in southwest China. We linked the relative growth rate of lianas with nine leaf traits associated with leaf morphology, nutrient concentrations, and water hydraulic capacity as indicated by leaf vein density, and five stem wood traits related to stem water transport capacity and wood density. Our results showed that deciduous lianas have higher relative growth rates than their evergreen counterparts. Across all lianas studied, the relative growth rate was positively correlated with the leaf area and specific leaf area, but negatively correlated with leaf dry matter content. The relative growth rate of lianas was strongly correlated with nitrogen concentration after excluding the legume liana species. The relative growth rate was decoupled from leaf phosphorus and potassium concentrations, leaf vein density, and stem vessel traits across all lianas investigated. For four evergreen lianas, there were positive associations of the relative growth rate with the leaf thickness and diameter of the largest vessels. This study is the first to illustrate the relationships of liana growth with leaf and stem traits in the high-elevation subtropical cloud forest. More studies from diverse forest ecosystems are needed to comprehensively understand the mechanism underlying liana growth patterns.


1984 ◽  
Vol 64 (4) ◽  
pp. 825-839 ◽  
Author(s):  
H. R. DAVIDSON ◽  
C. A. CAMPBELL

Manitou spring wheat (Triticum aestivum L.) was grown at combinations of three day/night temperatures (27/12 °C (T27), 22/12 °C (T22) and 17/12 °C (T17)), three levels of fertilizer N (58, 116 and 174 kg/ha), and three moisture stresses (nominally −0.03, −1.5 and −4.0 MPa) applied for four durations (viz., no stress throughout, stress from (i) four-tiller (Tg), (ii) near ligule of last leaf visible (LLV), or (iii) flowering (F1) stages to harvest (Hvst)). Weights of plant parts and photosynthetic area of leaves and stems were measured at eight growth stages. Mean net rate of photosynthesis [Formula: see text] was estimated by dividing plant dry weight by photosynthetic area duration. Temperature was the main factor affecting net photosynthesis and growth. Under optimum moisture and fertility, net photosynthesis was inversely related to temperature being 1.15, 1.19 and 1.29 μg∙cm−2∙day−1 at T27, T22 and T17, respectively. However, absolute growth rates were highest at T22. For example, at low moisture stress and N174, absolute growth rates were 0.69, 0.77 and 0.66 g∙day−1 at T27, T22 and T17, respectively. High moisture stress from Tg to maturity reduced absolute growth rate by about 60%. Low N rates also reduced absolute growth rate. Relative growth rate was constant and highest between emergence and LLV; it then declined rapidly and was negative after soft dough. It was suggested that the absolute growth rates and relative growth rates generated in this study could be adapted for use in simulation modelling exercises. Moisture stress was the most important factor influencing the proportion of the plant’s weight that was harvested in the grain (harvest index). Moisture stress from Tg to harvest resulted in a harvest index of 0.34 ± 0.03; for all other treatments the index was 0.28 ± 0.01. The rate and amount of water used by the plants was greatest at T27 and lowest at T22, consequently water use effeciency was lowest at T27 and highest at T22.Key words: Net photosynthesis, growth kinetics of wheat, leaf area duration


2013 ◽  
Vol 404 ◽  
pp. 420-424
Author(s):  
Heng Jia Zhang ◽  
Jun Hui Li

A trial was carried out to investigate the effect of limited water supply on leaf area duration (LAD), relative growth rate (RGR), crop growth rate (CGR), and above-ground biomass (AB) of spring maize. The results indicated that the LAD was significantly (p<0.05) increased by 10.6%, 15.4%, 16.9%, 19.3%, 13.4% and 17.0%,12.2%, 19.7%, 18.4%, 20.9% in MI1, MI3, MI4, MI5, CK than MI2 during both 12-leaf stage to heading and heading to silking. There was no significant difference (p>0.05) in RGR among all the treatments and check during 6-leaf to 12-leaf stage and silking to middle grain filling, but significant difference occurred during other measured stages. Also, significant difference was found in CGR among some treatments and check during all the measured growth stages. The maximum AB of maize was maintained in CK with 23.0 t ha-1, significantly improved by 16.2%, 16.2%, 22.3% and 41.1%, 35.3% respectively than in MI1, MI4, MI5 and MI2, MI3, and the minimum AB was recorded in MI2 with 16.3 t ha-1.


2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
M. M. A. Mondal ◽  
A. B. Puteh ◽  
M. A. Malek ◽  
M. R. Ismail ◽  
M. Y. Rafii ◽  
...  

Growth parameters such as leaf area (LA), total dry mass (TDM) production, crop growth rate (CGR), relative growth rate (RGR), and net assimilation rate (NAR) were compared in six varieties of mungbean under subtropical condition (24°8′ N 90°0′ E) to identify limiting growth characters for the efficient application of physiology breeding for higher yields. Results revealed that a relatively smaller portion of TDM was produced before flower initiation and the bulk of it after anthesis. The maximum CGR was observed during pod filling stage in all the varieties due to maximum leaf area (LA) development at this stage. Two plant characters such as LA and CGR contributed to the higher TDM production. Results indicated that high yielding mungbean varieties should possess larger LA, higher TDM production ability, superior CGR at all growth stages, and high relative growth rate and net assimilation rate at vegetative stage which would result in superior yield components.


1982 ◽  
Vol 62 (2) ◽  
pp. 575-586 ◽  
Author(s):  
R. J. RICHMOND ◽  
R. T. BERG

The muscle-weight distribution and relative growth rate patterns were determined for 96 muscles and nine anatomical muscle groups dissected from half carcasses of pigs from two studies. The first study involved 109 pigs representing barrows and gilts of three breed groups, fed two rations differing in energy and protein and slaughtered at weights ranging from 23 to 114 kg liveweight. The second study involved 72 pigs representing barrows and gilts of two breed groups, fed one of three levels of a low-energy ration and slaughtered at one of three liveweights from 68 kg to 114 kg. Of the 96 muscles dissected, 69 muscles each weighed less than 1% of total muscle, five ranged from 3 to 7% and one muscle was more than 10% of total muscle. Relative growth rate patterns of individual muscles and anatomical muscle groups from pigs were compared with other studies from cattle and sheep. Generally, relative muscle growth in pigs over the range in liveweight studied appeared to be more monophasic than in cattle or sheep. Relative growth rate of muscles and subsequent muscle distribution appeared to be related to muscle function. Muscles associated with mobility immediately after birth showed much earlier development than those concerned with propulsion. Muscles involved with posture appeared to grow at the same relative rate as total muscle. Key words: Pig, growth, muscle growth


2015 ◽  
Vol 39 (1) ◽  
pp. 177-187 ◽  
Author(s):  
Leonardo Bianco de Carvalho ◽  
Pedro Luis da Costa Aguiar Alves ◽  
Flávia Regina da Costa

Weed control is commonly performed by the inter-row mechanical weeding associated to intrarow glyphosate directed spraying, causing a risk for drift or accidental herbicide application, that can affect the crop of interest. The objective was to evaluate the response of clones C219, GG100, I144, and I224 of eucalypt (Eucalyptus grandis x E. urophylla) to glyphosate doses of 0, 18, 36, 72, 180, 360, and 720 g of acid equivalent per hectare. The clones showed different growth patterns with regard to height, leaf number, stem dry weight, relative growth rate, net assimilation rate, and relative leaf growth rate. The clones I144 and GG100 were more susceptible to glyphosate, showing the doses required to reduce dry weight by 50% of 113.4 and 119.6 g acid equivalent per hectare, respectively. The clones C219 and I224 were less susceptible to glyphosate, showing the doses required to reduce dry weight by 50% of 237.5 and 313.5 g acid equivalent per hectare, respectively. Eucalyptus clones respond differently to glyphosate exposure, so that among I224, C219, GG100, and I144, the susceptibility to the herbicide is increasing.


2013 ◽  
Vol 864-867 ◽  
pp. 1486-1489
Author(s):  
Xiao Yun Fu

Two aquatic macrophytes (Lythrum salicaria and Alisma plantago-aquatica) were grown in monoculture to test the relative growth rate (RGR) and abilities of removing total phosphorus (TP) by the manipulative indoor experiment. A nutrient treatment consisted of two levels of phosphorus [ low (3 mg L-1 N) and high (12 mg L-1 N) ] of nutrient solution. Result revealed that nutrients had significant affect on the RGR, however the RGR of the species was non-significant. The results showed that TP in wastewater were significantly higher from unvegetated microcosms compared to vegetated. L. salicaria was shown to be best removal effect with the removal rates of 81.7% and 91.1% at low and high concentrations of TP.


1970 ◽  
Vol 40 (2) ◽  
pp. 133-138 ◽  
Author(s):  
MMA Mondal ◽  
MSA Fakir ◽  
M Nurul Islam ◽  
MA Samad

Growth rate of mungbean was very slow during the vegetative phase in all the four genotypes. A relatively smaller portion of total dry matter (TDM) was produced before flower initiation and the bulk of it after anthesis. The maximum crop growth rate (CGR) was observed due to maximum leaf area (LA) development during the pod filling stage in all the genotypes. LA and CGR contributed to the superior TDM production. It appeared that a high yielding mungbean genotype should possess larger LA, high TDM production ability, superior CGR at all the growth stages, high relative growth rate and net assimilation rate at the vegetative stage as superior yield components. Key words: Seed yield; Mungbean; Growth; Dry matter DOI: http://dx.doi.org/10.3329/bjb.v40i2.9768   Bangladesh J. Bot. 40(2): 133-138, 2011 (December)  


Author(s):  
Mohamed Ewis Abdelaziz ◽  
A. H. Hannfy Ahmed ◽  
R. S. Bekhid ◽  
Robert Pokluda

This work was conducted to study the effect of five NPK fertigation levels on the growth rate of sweet pepper (Capsicum annuum L. cv. Bruyo) grown under the plastic greenhouse using different growth analysis formulas. Leaf area ratio (LAR), specific leaf area (SLA), relative growth rate (RGR) and net assimilation rate (NAR) was evaluated in two periods (60–90 and 90–120 days after transplanting). The mean values of LAR, SLA, RGR and NAR tended to decrease significantly with advancing plant age in both seasons. In general, at the moderate level (34N-42P-29K / plastic house 540 m2) was found the highest significant values of LAR and SLA in the two growth periods. On the other hand, the highest values of NAR were recorded at the plants treated with the lowest NPK fertigation level (17N-21P-15K / plastic house 540 m2). However, increase of NPK fertigation doses to the moderate levels had favorable effects on LAR and SLA of sweet pepper plants.


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