scholarly journals Estudio de la propagación sexual del arboloco Montanoa quadrangularis Schultz Bipontianus Asteraceae

2010 ◽  
Vol 15 (1) ◽  
pp. 37
Author(s):  
Marcela Tamayo-Rincón ◽  
Loyla Rodríguez-Perez ◽  
William Escobar-Torres

<p><strong> Objective.</strong> To develop sexual propagation methodologies for <em>Montanoa quadrangularis </em>Schultz  Bipontianus (<em>arboloco</em>). <strong>Materials and methods. </strong>Seeds were harvested from trees grown at the Chilaca environmental station (Geoambiente Ltda.) located in Pacho, Cundinamarca, Colombia. The study was carried out in two phases: firstly, substrate effect on germination responses was evaluated in seedbed conditions. Substrates evaluated were: local soil, local soil mixed with worm humus, and peat. Additionally, two spatial arrangements were assessed:  seeds sown at random and at 0.5 cm in depth. Secondly, in nursery conditions the effect of the substrates local soil, local soil mixed with worm humus and peat, as well as the effect of developmental stages of the plants (with 2, 4, and 6 leaves) on their further growth and development were evaluated. <strong>Results. </strong>In seedbed conditions, the germination capacity was highly influenced by peat substrate (83.67%) whereas in local soil the germination capacity was 40.83%.   In  nursery conditions, 6-leaf plants grown  in  local soil mixed with worm humus showed the best responses on parameters such as  plant total length  (9.51 cm), leaf area (36.69 cm<sup>2</sup>), and total dry weight (0.10 g). <strong>Conclusions. </strong>The type of substrate used in seedbed conditions influenced the germination capacity of <em>M</em><em>. quadrangularis</em> seeds. The substrate and the developmental stage of the plant had a significant influence on the growth and development of <em>arboloco</em> plants.</p> <p><strong>Key words: </strong>germination indices, plant growth and development, forestry species.</p><br />

HortScience ◽  
1996 ◽  
Vol 31 (4) ◽  
pp. 633c-633
Author(s):  
C.L.H. Finneseth ◽  
Desmond R. Layne ◽  
R.L. Geneve

Little scientific information is available describing morphological development of pawpaw during seed germination. To provide this information, a study was designed to outline important developmental stages and describe seedling characteristics within each stage. Stratified pawpaw seeds were sown in vermiculite and germinated at 25°C in a growth chamber. Ten seedlings were randomly chosen and destructively harvested at 5-day intervals starting at radicle protrusion. Length (mm), fresh and dry weight, and percentage of total dry weight were determined for seedling components. Pawpaw seeds have a small rudimentary embryo with all food reserves stored in a ruminate endosperm. Dry weight measurements showed a dramatic reallocation of reserves from the storage tissue to developing seedling parts. Initial embryo length was less than 3 mm, but within 70 days seedlings exceeded 350 mm. Twelve days after planting, simultaneous radicle and cotyledon growth occurred (3.4 and 3.0 mm, respectively), but neither hypocotyl nor epicotyl was visible. Radicle protrusion was observed at 15 days with radicle, cotyledon and hypocotyl lengths increasing to 4.4, 4.0, and 3.2 mm, respectively. Endosperm comprised 99.1% of total dry weight at this stage. The hypocotyl hook emerged after 30 days and endosperm comprised 76.1% of total dry weight. Cotyledons reached maximum length (29.0 mm) at day 40 and the epicotyl was discernible. At 55 days, the seed coat containing cotyledons and residual endosperm abscised and the average radicle, hypocotyl and epicotyl lengths were 182.0, 61.1, and 7.3 mm, respectively. It is suggested that the cotyledons primary function is absorption of food reserves from the endosperm for transfer to the developing seedling.


1982 ◽  
Vol 33 (6) ◽  
pp. 1009 ◽  
Author(s):  
RJ Chamberlin ◽  
GL Wilson

Growth and development of two grain-sorghum hybrids (De Kalb E57 and Texas 610) were examined under glasshouse conditions by sequential harvesting and the use of I4C. The grain yield per plant of Texas 610 was higher than that of E57, with higher total biological yield and similar harvest indices. The contribution to grain weight at maturity, of carbon assimilated prior to anthesis, was about 10% for each hybrid. The leaves were the main source of this material. After anthesis, dry weight data indicated that temporary storage of assimilates before retranslocation to the grain was of greater importance in Texas 610 than E57. This storage was largely in the leaves (including sheaths), upper internodes, and roots. A high grain-growth rate was maintained for longer by Texas 610 than by E57. Total dry weight production after anthesis in both hybrids was, at all stages examined, more than sufficient to maintain grain growth.


Author(s):  
AG Sficas ◽  
IC Antoniou

AbstractGrowth and development of seven Oriental tobacco cultivars, representing aromatic, neutral and taste type tobacco grown in Greece, were studied at Drama, Greece, during 1982 and 1983. The growing period from transplanting to flowering ranged from 65 to 80 days and was the same for both years. plant height increase followed a sigmoid curve, the number of harvestable leaves developed almost linearly with time, and total dry weight production and leaf area increase can be described by a logarithmic curve. The effect of year on all parameters was significant, but cultivar differences were consistent. Assimilation rates during the whole period ranged from 0.1 g to 3.0 g per day per plant in 1982, and from 0.1 g to 2.7 g in 1983. Dry weight distribution in the plant parts and final yield production for the cultivars tested were also recorded.


2018 ◽  
Vol 96 (4) ◽  
pp. 628 ◽  
Author(s):  
Yolanda Donají Ortiz-Hernández ◽  
Germán Fernando Gutiérrez-Hernández ◽  
Luis Jorge Corzo-Ríos ◽  
Elpidio García-Ramírez ◽  
Sabino Honorio Martínez-Tomás

<p><strong>Background: </strong><em>Agave potatorum</em> reproduces mainly through seeds is widely collected for the mezcal production, and there is currently a marked decrease in their wild populations. Therefore, to contribute to its sustainable use, it is important to characterize the morphology of its seeds and to know their germinative characteristics.</p><p><strong>Research question:</strong> Do the year and the collection site have an effect on the size, color, viability and germination capacity of <em>Agave potatorum</em> seeds?</p><p><strong>Species studied</strong>: <em>Agave potatorum</em> Zucc.</p><p><strong>Study site and period of research:</strong> Seeds of <em>Agave potatorum</em> were collected in Oaxaca, Mexico: Miahuatlán (MIAH), in 2014; Coixtlahuaca (COIX), in 2015; and Zaachila (ZAA), in 2015 and 2016.</p><p><strong>Methods:</strong> For the seeds, we analyzed four physical descriptors, five color coordinates, and nine germination variables. We used a completely randomized design with four replications (100 seeds). An analysis of variance, a comparison of means, and a linear correlation analysis were performed.</p><p><strong>Results:</strong> We found that the ZAA16 seeds showed the highest values (<em>P</em> &lt; 0.05) for weight and size, and for the luminosity coordinate (L*, 15.2). Color coordinate values revealed a black color of the seeds, which significantly diminished in luminosity with seeds age and varied with their origin. The coordinate L* was correlated significantly with the total dry weight of seedlings and seed volume.</p><p><strong>Conclusions:</strong> <em>Agave potatorum </em>seeds significantly changed their physical dimensions and germination capacity according to their origin. The luminosity of the black color of seeds decreased with seed age and was correlated with seed volume and seedling total dry weight.</p>


FLORESTA ◽  
2012 ◽  
Vol 42 (2) ◽  
pp. 347
Author(s):  
Ângela Simone Freitag ◽  
Felipe Uassurê Nery ◽  
Fabiana Ribeiro Rossi ◽  
Antônio Natal Gonçalves

 O presente trabalho teve por objetivo comparar o crescimento e desenvolvimento de explantes caulinares de C. citriodora nos meios de cultura JADS e MS, mensurando-se a produção de biomassa total, proteínas totais e açúcares totais solúveis. O delineamento experimental utilizado foi de blocos ao acaso, organizados em esquema bifatorial, com parcela subdividida no tempo com três repetições por tratamento. Tratamentos: T1 (testemunha, 40 ml de meio por frasco); T2 (40 ml de meio por frasco e adição de 10 ml no dia 6); T3 (40 ml de meio por frasco e adição de 10 ml nos dias 6 e 9). Como subparcelas, sete épocas de avaliação (0, 3, 6, 9, 12, 15, 18). Concluiu-se que para o meio JADS é mais recomendado que se efetuem duas adições de meio durante a fase desenvolvimento dos explantes. Já para o MS, aconselha-se não adicionar meio de cultura durante o desenvolvimento do C. citriodora.Palavras-chave: JADS; MS; micropropagação; desenvolvimento. AbstractComparative study between two environments for cultivation of Corymbia citriodora in vitro. This research aimed to compare growth and development of C. citriodora shoots in JADS and MS environments measuring the total dry weight, total proteins, and total soluble sugars. The experimental design employed was randomized blocks, arranged in bifactorial model, with timing split plots with three replications per treatment. Treatments: T1 (control, 40 ml of medium per bottle, without addition during the assessment), T2 (40 ml of medium per bottle adding 10 ml just on third day of assessment), T3 (40 ml of medium per bottle adding 10 ml on third and fourth days of assessment) as subplots, seven assessment periods (0, 3, 6, 9, 12, 15, 18). As result, for the medium JADS it is recommended two additions of culture medium during the explants development. For MS it is not indicated add cultivating environment during C. citriodora development.Keywords: JADS; MS; micropropagation; development.  


1969 ◽  
Vol 60 (1) ◽  
pp. 91-100 ◽  
Author(s):  
Charles S. Nicoll

ABSTRACT The response of the pigeon crop-sac to systemically acting prolactin (injected subcutaneously) was evaluated by measuring the wet weight of the responsive lateral lobes of the organ and by determining the dry weight of a 4 cm diameter disc of mucosal epithelium taken from one hemicrop. Of several different injection schedules tested, administration of prolactin in four daily injections was found to yield optimal responses. When compared with a graded series of prolactin doses, measurement of the mucosal dry weight proved to be a better method of response quantification than determination of the crop-sac wet weight with respect to both assay sensitivity and precision. The submucosal tissue of the crop-sac was estimated to constitute about 64 % of the total dry weight of the unstimulated organ and it was found to be relatively unresponsive to prolactin stimulation in comparison with the mucosa. The lipid content of the mucosal epithelium was determined using unstimulated crop-sacs or tissues which showed varying degrees of prolactin-induced proliferation. The fat content of the mucosal epithelial cells increased only slightly more rapidly than the dry weight or the defatted dry weight of the mucosa. Suggestions are made for the further improvement of the systemic crop-sac assay for prolactin.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 508e-508
Author(s):  
Bin Liu ◽  
Royal D. Heins

A concept of ratio of radiant to thermal energy (RRT) has been developed to deal with the interactive effect of light and temperature on plant growth and development. This study further confirms that RRT is a useful parameter for plant growth, development, and quality control. Based on greenhouse experiments conducted with 27 treatment combinations of temperature, light, and plant spacing, a model for poinsettia plant growth and development was constructed using the computer program STELLA II. Results from the model simulation with different levels of daily light integral, temperature, and plant spacing showed that the RRT significantly affects leaf unfolding rate when RRT is lower than 0.025 mol/degree-day per plant. Plant dry weight is highly correlated with RRT; it increases linearly as RRT increases.


HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 468b-468
Author(s):  
Stephen F. Klauer ◽  
J. Scott Cameron ◽  
Chuhe Chen

After promising results were obtained with an open-style split trellis (two top wires) in its initial year, two new trials were established in 1997 in northwest (Lynden) and southwest (Woodland) Washington. For the split trellis, actual yields were 33% (machine-picked 1/2 season) and 17% (hand-picked) greater, respectively, for the two locations compared to the conventional trellis (one top wire). In Woodland, canes from the split trellis had 33% more berries, 55% more laterals, 69% more leaves, and 25% greater leaf area compared with the conventional trellis. Greatest enhancement of these components was in the upper third of the canopy. Laterals were also shorter in this area of the split canopy, but there was no difference in average total length of lateral/cane between trellis types. Total dry weight/cane was 22% greater in the split trellis, but component partitioning/cane was consistent between the two systems with fruit + laterals (43%) having the greatest above-ground biomass, followed by the stem (30% to 33%) and the leaves (21% to 22%). Measurement of canopy width, circumference, and light interception showed that the split-trellis canopy filled in more quickly, and was larger from preanthesis through postharvest. Light interception near the top of the split canopy was 30% greater 1 month before harvest with 98% interception near the top and middle of that canopy. There was no difference between the trellis types in leaf CO2 assimilation, spectra, or fluorescence through the fruiting season, or in total nitrogen of postharvest primocane leaves.


Agronomy ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1151
Author(s):  
Sadam Hussain ◽  
Saddam Hussain ◽  
Zubair Aslam ◽  
Muhammad Rafiq ◽  
Adeel Abbas ◽  
...  

Dry direct-seeded rice has been shown to save irrigation water and labor. Nonetheless, irrigation management in dry direct-seeded rice has received very little attention. Here, we examined the potential of different irrigation regimes: aerobic rice (AR), alternate wetting and drying (AWD) and continuous flooding (CF) in dry direct-seeded rice cultivation on two rice cultivars (Pride-1 (hybrid indica) and NB-1 (inbred indica)). Growth, yield attributes, grain yield, total water input, water productivity and benefit cost ratio were measured. Our results showed that AR saved 11.22 and 28.40%, and 5.72 and 32.98% water compared with AWD and CF during 2018 and 2020, respectively. There was a significant difference in grain yield among treatments and cultivars. AWD and CF produced statistically same total dry weight and grain yield, while AR reduced the total dry weight by 31.34% and 38.04% and grain yield by 34.82% and 38.16% in comparison to AWD and CF, respectively, across the years. Except for 1000-grain weight and harvest index in AWD and CF, further differences in total dry weight and grain yield among irrigation treatments were primarily correlated with variations in yield attributes. Among the cultivars, hybrid rice performed better than inbred rice. Over the two-year period, hybrid rice increased total dry weight, grain yield, and water productivity by 9.28%, 13.05%, and 14.28%, respectively, as compared to inbred rice. Regarding water productivity (WP), the maximum percentage (40.90 and 26.53%) was recorded for AWD compared to AR and CF. Among cultivars, more water productivity (14.28%) was calculated for hybrid rice than inbred one. Chlorophyll and carotenoid contents, leaf area index and crop growth rate contributed to higher grain yield of hybrid rice under AWD and CF. In contrast to WP, the maximum benefit cost ratio was estimated to be higher for CF than that of AR and AWD. For the cultivars, the maximum value (2.26 in 2018 and 2.32 in 2020) was calculated for hybrid rice compared with the inbred one. In conclusion, these results suggests that AWD with maximum WP and CF with maximum BCR could be more efficient approaches than AR. Under CF, hybrid rice cultivars with higher yield and yield-related attributes, WP and BCR performed better.


Weed Science ◽  
1988 ◽  
Vol 36 (6) ◽  
pp. 751-757 ◽  
Author(s):  
David T. Patterson ◽  
Maxine T. Highsmith ◽  
Elizabeth P. Flint

Cotton, spurred anoda, and velvetleaf were grown in controlled-environment chambers at day/night temperatures of 32/23 or 26/17 C and CO2concentrations of 350 or 700 ppm. After 5 weeks, CO2enrichment to 700 ppm increased dry matter accumulation by 38, 26, and 29% in cotton, spurred anoda, and velvetleaf, respectively, at 26/17 C and by 61, 41, and 29% at 32/23 C. Increases in leaf weight accounted for over 80% of the increase in total plant weight in cotton and spurred anoda in both temperature regimes. Leaf area was not increased by CO2enrichment. The observed increases in dry matter production with CO2enrichment were caused by increased net assimilation rate. In a second experiment, plants were grown at 350 ppm CO2and 29/23 C day/night for 17 days before exposure to 700 ppm CO2at 26/17 C for 1 week. Short-term exposure to high CO2significantly increased net assimilation rate, dry matter production, total dry weight, leaf dry weight, and specific leaf weight in comparison with plants maintained at 350 ppm CO2at 26/17 C. Increases in leaf weight in response to short-term CO2enrichment accounted for 100, 87, and 68% of the observed increase in total plant dry weight of cotton, spurred anoda, and velvetleaf, respectively. Comparisons among the species showed that CO2enrichment decreased the weed/crop ratio for total dry weight, possibly indicating a potential competitive advantage for cotton under elevated CO2, even at suboptimum temperatures.


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