Sexual differences in shoot and leaf dynamics in the dioecious tree Salix sachalinensis

2006 ◽  
Vol 84 (12) ◽  
pp. 1852-1859 ◽  
Author(s):  
Naoto Ueno ◽  
Hiroshi Kanno ◽  
Kenji Seiwa
Keyword(s):  
Reproductive Investment ◽  
Reproductive Organs ◽  
Tissue Loss ◽  
Shoot Biomass ◽  
Carbon Gain ◽  
Reproductive Costs ◽  
Vegetative Shoot ◽  
Leaf Production ◽  
Salix Sachalinensis ◽  
Terminal Shoot

In the dioecious tree Salix sachalinensis Fr. Schm., females invested a greater amount of biomass to reproductive organs compared with males, indicating a greater reproductive cost in females. To elucidate mechanisms for the compensation of reproductive costs in females, we examined differences between the sexes in resource allocation, leaf and shoot dynamics, and leaf photosynthetic ability. In individual 1-year-old shoots, greater vegetative shoot biomass was observed in females than in males, although the mean mass of individual vegetative shoots was lower in females than in males. In both sexes, vegetative shoots at the proximal end of 1-year-old shoots completed their annual leaf production earliest and began shedding leaves earliest, although the light conditions did not differ from those at the terminal end. The leaf and shoot structure and dynamics in S. sachalinensis suggest effective carbon gain for both sexes by always placing new leaves with high photosynthetic rates at terminal shoot positions. In females, in particular, the net carbon gain would be increased by reducing construction and respiration costs and tissue loss by placing inexpensive small shoots in proximal shoot positions. To investigate to what extent the photosynthetic capacity of short-lived shoots compensated for reproductive costs in females, 80% of the vegetative-shoot buds were removed from 1-year-old shoots in females and males to simulate natural shoot shedding. In the current year, shoot removal did not reduce reproductive investment, but strongly reduced the diameter growth of 1-year-old shoots, in which the reduction was much greater in females than in males. In the following year, a reduction in reproductive investment was observed in females. Females of S. sachalinensis compensated for reproductive costs, not only by investing a greater amount of biomass in vegetative shoots, but also by using a more effective system of carbon acquisition (rapid leaf turnover on inexpensive shoots) than males.

The effect of ozone on cottonwood – leaf rust interactions: independence of abiotic stress, genotype, and leaf ontogeny

1987 ◽  
Vol 65 (5) ◽  
pp. 949-953 ◽  
Author(s):  
James S. Coleman ◽  
Clive G. Jones ◽  
William H. Smith
Keyword(s):  
Leaf Rust ◽  
Populus Deltoides ◽  
Leaf Age ◽  
Leaf Length ◽  
Ozone Treatment ◽  
Shoot Biomass ◽  
Leaf Ontogeny ◽  
Leaf Production ◽  
Leaf Injury ◽  
Eastern Cottonwood

The interaction of an acute ozone dose, plant genotype, and leaf ontogeny on the development of cottonwood leaf rust on eastern cottonwood (Populus deltoides Bartr.) was investigated. A rust-resistant (ST 66) and a rust-susceptible (ST 109) clone were exposed to charcoal-filtered air or were fumigated with 393 μg m−3 (0.20 ppm) ozone for 5 h. Forty hours after fumigation, leaf material of different developmental ages was inoculated with urediospores of Melampsora medusae Thum., and uredia production was measured after 10 days. Ozone fumigation of cottonwoods significantly reduced uredia production by M. medusae on both clones and all leaf ages without causing visible leaf injury or measurable changes in cottonwood height growth, leaf production, leaf length, or root/shoot biomass. Uredia production was strongly affected by ozone treatment, cottonwood genotype, and leaf age, but interactions among these three factors did not occur.

scholarly journals Sensitivity of quinoa cv. ‘Titicaca’ to low salinity conditions

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
María del Carmen Rodríguez-Hernández ◽  
Luna Morcillo ◽  
Idoia Garmendia
Keyword(s):  
Photosynthetic Rate ◽  
Chenopodium Quinoa ◽  
Dry Weight ◽  
Nutrient Content ◽  
Progressive Increase ◽  
Shoot Biomass ◽  
High Concentration ◽  
Negative Effects ◽  
Leaf Production ◽  
Moderate Salinity

Abstract Quinoa (Chenopodium quinoa Will.) is an annual herbaceous Andean plant. In recent years there is a growing interest on it due to its high quality as food, its wide adaptation to agroecological conditions and resistance to different abiotic stresses. In this work, we evaluate the growth pattern of quinoa plants cv. ‘Titicaca’, subjected to different levels of salinity, focusing on leaf production and nutrient content. In this sense, the results have shown that a high concentration of salinity negatively affects the growth of quinoa plants. In fact, plants grown with 200 mM NaCl reduced the photosynthetic rate and levels of chlorophylls and carotenoids in comparison with the rest of the treatments. Likewise, it has been proven how the progressive increase in salinity has negative effects on transpiration, stomatal conductance and photosynthetic rate, with significant subsequent reductions in shoot biomass, leaf area and nutrient adquisition, but without a decline in leaf dry weight (DW) production. However, the treatment of 200 mM NaCl demonstrated the best results regarding the water-use efficiency, as well as the number of saline glands. According to our results, the quinoa plant cv. ‘Titicaca’ seems to be tolerant to moderate concentrations of salinity (50–100 mM NaCl). This study could serve as a reference on this little known and cultivated species in the Mediterranean region, since it could become an alternative crop in areas with moderate salinity problems.

Annual cycle of reproductive organs in a Tibetan frog, Nanorana parkeri

2010 ◽  
Vol 60 (3) ◽  
pp. 259-271 ◽  
Author(s):  
Xin Lu ◽  
Xiaoyan Ma
Keyword(s):  
Reproductive Cycle ◽  
Annual Cycle ◽  
Wild Population ◽  
Reproductive Investment ◽  
Reproductive Organs ◽  
Ovarian Follicles ◽  
Sexual Differences ◽  
Annual Reproductive Cycle ◽  
Histological Sections ◽  
Resting Period

AbstractThe annual cycle of reproductive organs in a wild population of a Tibetan frog, Nanorana parkeri, was studied. For females we used the pigmentation and size of the ovarian follicles to designate the reproductive conditions. Males were analyzed according to their spermatogenic stages using histological sections of their testes. The results showed that each sex had a seasonal reproductive cycle. However, females reproduced biennially or more, while males bred annually. We presumed that the sexual differences in reproductive investment contributed to the annual reproductive cycle difference between the sexes of N. parkeri. Moreover, this species did not have the post-breeding resting period, which was confirmed by the fact of reinitiation of spermatogenesis shortly after breeding.

Temperature effect on biomass production and root/shoot biomass ratios in two arctic sedges under controlled environmental conditions

1984 ◽  
Vol 62 (10) ◽  
pp. 2150-2153 ◽  
Author(s):  
Jochen Kummerow ◽  
Barbara A. Ellis
Keyword(s):  
Biomass Production ◽  
Environmental Conditions ◽  
Large Fraction ◽  
The Arctic ◽  
Shoot Biomass ◽  
Eriophorum Vaginatum ◽  
Temperature Optimum ◽  
Active Growth ◽  
Leaf Production ◽  
Higher Temperature

The effect of differential root and shoot temperatures on biomass production of the arctic sedges Eriophorum vaginatum and Carex bigelowii was analyzed under controlled environmental conditions. Both species showed active growth at 2 °C root and shoot temperatures although warmer conditions substantially enhanced biomass production. In E. vaginatum, under the optimal 12 °C root and 12 °C shoot temperature regime, about six times more biomass was produced than under the 2 °C conditions. The corresponding temperatures for C. bigelowii were 12 °C root and 22 °C air, although the data did not preclude a higher temperature optimum for this species. The results support the hypothesis that in arctic sedges the root/shoot biomass ratios are small with low root temperatures, i.e., a relatively large fraction of the photosynthate is allocated to leaf production under cold conditions.

scholarly journals Influence of High Tunnel and Field Conditions on Strawberry Growth and Development

HortScience ◽  
2006 ◽  
Vol 41 (2) ◽  
pp. 329-335 ◽  
Author(s):  
Sorkel Kadir ◽  
Edward Carey ◽  
Said Ennahli
Keyword(s):  
Leaf Area ◽  
Fruit Quality ◽  
Growth Yield ◽  
Fruit Production ◽  
Field Conditions ◽  
Soluble Solids ◽  
Shoot Biomass ◽  
Leaf Production ◽  
High Tunnel ◽  
Solids Concentration

Plant growth, yield, and fruit quality of two strawberries (Fragaria ×ananassa Duch.)—`Chandler' and `Sweet Charlie'—grown under high tunnels (HTs) were compared with that of field plants during 2002–03 and 2003–04 growing seasons. Plug plants were planted in mid-October 2002 and mid-September 2003 on raised beds covered with black polyethylene mulch. Microclimate of the HTs protected strawberry crowns from winter damage and advanced fruit production 5 weeks earlier than that of plants grown under field conditions. From December to February, average minimum and maximum crown temperatures under the HTs were 5 and 12 °C warmer than those of the field crowns, respectively. The earliest HT fruit were harvested on 7 Apr. 2003 and 11 Mar. 2004. Yield and fruit quality under the HTs were superior to that of field-grown plants. HT plants, especially `Sweet Charlie', bloomed earlier than did field plants, but `Chandler' produced higher yield than `Sweet Charlie' late in the season. Larger fruit with higher soluble solids concentration (SSC) were produced inside the HTs than outside. HT `Sweet Charlie' fruit were sweeter than `Chandler' fruit, but `Chandler' produced larger fruit. Larger leaf area, greater number of leaves and shoot biomass, more branch-crowns, and fewer runners were developed under HTs than field conditions. Total leaf area, leaf production, total shoot biomass, and number of branch-crowns of HT `Chandler' were greater than HT `Sweet Charlie'. Results of this study indicate that strawberry plants under HTs were not only precocious, but also produced higher yields and superior quality to that of field plants. HT conditions suppressed runner growth, but enhanced branch-crown development.

scholarly journals ISOLATE TWO SPECIES OF COMPOSITAE FAMILY E.armatus BOISS&HAUSSKN AND E.cephalotes DC. BY MORPHOLOGICAL AND VEGETATIVE SHOOT APEX FOR THE FIRST TIME IN IRAQ

2017 ◽  
Vol 48 (5) ◽  
Author(s):  
Al-Musawi & et al.
Keyword(s):  
Plant Species ◽  
Shoot Apex ◽  
Pollen Grains ◽  
Reproductive Organs ◽  
The Other ◽  
Vegetative Shoot ◽  
Northern Areas ◽  
Vegetative Shoot Apex ◽  
Perennial Herbs ◽  
First Time

Present study delts with morphological and vegetative shoot apex characteristics of two species  Echinops armatus and E.cephalotes (compositae) which collected during trips field to the northern areas of Iraq in the seasons of growth 2012-2014. As it presents the results and characters  had been shown for the first time in Iraq. plant species are perennial herbs spinous with woody, strong and solid stems that covered with many types of indumentums like spines and hairs, the study included characters of stems, leaves, involucres bracts and inflorescences as well as characters of growing points of the two species, and by examining buds in inflorescences found that the flowers are hermaphrodite, not sterile which containing all the reproductive organs like stamens, pollen grains, pistils and ovaries, an early dehesence as mature anthers and bloom before the maturation of pistils and disperse their pollen.The study also discussed variations within the characters and it became clear that the characters of leaves, stems and involucres especially inner cycle, including the importance of taxonomic great isolate the two species. Ranged prepare involucres braces  in the first species is (20-23) bracts while the number varied between (19-20) bracts in the other one. The study showed the importance of growing points  in isolating the two species where characterized by two meristematic area in longitudinal embryos species. The first spices recognized by two rows of cells, while the other one marked three rows or layers of components of Tunica cells area, and ensures find accurate measurements of parts phenotypic as well as illustrations of morphological and anatomical parts studied.                   

scholarly journals Carbon Balance of Turfgrass Systems in Response to Seasonal Temperature Changes Under Different Mowing Heights

2015 ◽  
Vol 140 (4) ◽  
pp. 317-322 ◽  
Author(s):  
Yali Song ◽  
Patrick Burgess ◽  
Hairong Han ◽  
Bingru Huang
Keyword(s):  
High Temperatures ◽  
Carbon Balance ◽  
Photosynthetic Capacity ◽  
Poa Pratensis ◽  
Global Climate ◽  
Kentucky Bluegrass ◽  
Shoot Biomass ◽  
Carbon Gain ◽  
Seasonal Temperature ◽  
Response To Temperature

Turfgrass growth and physiological activities are sensitive to temperatures and are affected by mowing height. Increasing temperatures associated with global climate change may limit photosynthetic capacity of established turfgrass stands. The objective of this study was to determine the effects of mowing height on carbon exchange of a turfgrass system and consequential effects on turfgrass growth in response to temperature variations across the growing season in kentucky bluegrass (Poa pratensis cv. Baron) stands. Mature (8 years old) turfgrass was mowed at 7.6 cm [high mowing height (HM)] or 3.8 cm [low mowing height (LM)] during 2012 and 2013. Both LM and HM plots displayed significant decline in turf quality (TQ), shoot biomass, and canopy photosynthetic rate (Pn) with increasing air temperature above 23–24 °C in both years and the decline was more pronounced for LM plots. Turf plots were carbon emitters when total respiration rate of shoots, roots, and soil (Rtotal) exceeded canopy Pn under high temperatures during July–September but maintained net carbon gain during cooler seasons (May and June) due to greater Pn to Rtotal ratio (Pn:Rtotal). Lowering mowing height accelerated carbon loss by reducing canopy Pn, particularly under high temperatures. Our results suggested that whether mature turfgrass stands fix or emit carbon is heavily dependent on interaction between seasonal temperatures and mowing height gauging whole-stand photosynthetic capacity. Furthermore, increasing mowing height during summer months may offset the deleterious effects of high temperature by maintaining positive carbon balance within the turfgrass system.

Phenotypic Plasticity of Chinese Sprangletop (Leptochloa chinensis) in Competition with Seeded Rice

2011 ◽  
Vol 25 (4) ◽  
pp. 652-658 ◽  
Author(s):  
Bhagirath S. Chauhan ◽  
David E. Johnson
Keyword(s):  
Growth Rate ◽  
Leaf Area ◽  
Production Rate ◽  
Tiller Number ◽  
Shoot Biomass ◽  
Assimilation Rate ◽  
Leaf Production ◽  
Relative Growth ◽  
Rice Plants ◽  
Net Assimilation

Chinese sprangletop, a C4species, is one of the most important grass weeds of seeded rice in Asia. Chinese sprangletop biology was studied by growing it alone and in competition with 4 and 12 rice plants. Rice competition did not affect the height of Chinese sprangletop, and the weed grew taller than rice, regardless of the competition. Compared with Chinese sprangletop grown alone, competition from rice reduced Chinese sprangletop leaf number, leaf production rate, tiller number, tiller production rate, leaf area, shoot biomass, relative growth rate, and net assimilation rate. Leaf area and shoot biomass of Chinese sprangletop when grown in competition with 12 rice plants was only 16% and 13%, respectively, of the leaf area and biomass of the weed grown alone.

Effect of Salinity on Growth of Barnyardgrass (Echinochloa crus-galli), Horse Purslane (Trianthema portulacastrum), Junglerice (Echinochloa colona), and Rice

Weed Science ◽  
2013 ◽  
Vol 61 (2) ◽  
pp. 244-248 ◽  
Author(s):  
Bhagirath S. Chauhan ◽  
Seth B. Abugho ◽  
Junrey C. Amas ◽  
Glenn B. Gregorio
Keyword(s):  
Electrical Conductivity ◽  
Regression Analysis ◽  
Salt Stress ◽  
Root Biomass ◽  
Control Treatment ◽  
Shoot Biomass ◽  
Weed Species ◽  
Leaf Production ◽  
Trianthema Portulacastrum ◽  
Significant Area

In Asia, a significant area under rice is affected by salinity. Salt stress can affect growth of crops as well as weeds. A study was conducted in a greenhouse to determine the effect of salinity (electrical conductivity [EC] of 1, 6, 12, 18, and 24 dS m−1) on growth of barnyardgrass, horse purslane, junglerice, and rice. Growth variables were analyzed using regression analysis. The tested levels of EC influenced leaf production of barnyardgrass and junglerice but not that of horse purslane. As compared with the control treatment (EC of 1 dS m−1), shoot biomass of barnyardgrass decreased by only 24% at 12 dS m−1, whereas rice biomass declined by 59% at this level of EC. At EC of 24 dS m−1, barnyardgrass still produced 4% of the biomass of the control treatment, whereas rice did not survive at this level of EC. Junglerice shoot biomass decreased by 73% at 18 dS m−1 EC compared with the control treatment, whereas rice shoot biomass declined by more than 86% at 18 dS m−1 EC. An EC of 10 dS m−1 was required to inhibit 50% shoot biomass of rice, whereas the EC to inhibit 50% shoot biomass of barnyardgrass and junglerice was 15 and 13 dS m−1, respectively. Shoot biomass of horse purslane was not influenced by the tested levels of EC. At the highest EC (24 dS m−1), at which rice did not survive, horse purslane shoot biomass was similar to that of the control treatment. In all weed species, data for root biomass showed trends similar to those of shoot biomass. The results of this study suggest that weeds were more tolerant to salt than rice, and horse purslane was the most tolerant species among the weeds.

scholarly journals Behavioral and physiological flexibility are used by birds to manage energy and support investment in the early stages of reproduction

2010 ◽  
Vol 56 (6) ◽  
pp. 767-792 ◽  
Author(s):  
François Vézina ◽  
Katrina G. Salvante
Keyword(s):  
Egg Production ◽  
Egg Size ◽  
Behavioral Flexibility ◽  
Reproductive Investment ◽  
Tissue Remodeling ◽  
Reproductive Organs ◽  
Energy Budgets ◽  
Phenotypic Flexibility ◽  
Zebra Finches ◽  
Daily Energy

Abstract Interest in phenotypic flexibility has increased dramatically over the last decade, but flexibility during reproduction has received relatively little attention from avian scientists, despite its possible impact on fitness. Because most avian species maintain atrophied reproductive organs when not active, reproduction in birds requires major tissue remodeling in preparation for breeding. Females undergo rapid (days) recrudescence and regression of their reproductive organs at each breeding attempt, while males grow their organs ahead of time at a much slower rate (weeks) and may maintain them at maximal size throughout the breeding season. Reproduction is associated with significant metabolic costs. Egg production leads to a 22%-27% increase in resting metabolic rate (RMR) over non-reproductive values. This is partly due to the activity of the oviduct, an organ that may allow females to adjust reproductive investment by modulating egg size and quality. In males, gonadal recrudescence may lead to a 30% increase in RMR, but the data are inconsistent and general conclusions regarding energetic costs of reproduction in males will require more research. Recent studies on captive female zebra finches describe the impacts of these costs on daily energy budgets and highlight the strategies used by birds to maintain their investment in reproduction when energy is limited. Whenever possible, birds use behavioral flexibility as a first means of saving energy. Decreasing locomotor activity saves energy during challenges such as egg production or exposure to cold temperatures and is an efficient way to buffer variation in individual daily energy budgets. However, when behavioral flexibility is not possible, birds must rely on flexibility at the physiological level to meet energy demands. In zebra finches breeding in the cold, this results in a reduced pace of laying, likely due to down-regulation of both reproductive and non-reproductive function, allowing females to defend minimal egg size and maintain reproductive success. More research involving a range of species in captive and free-living conditions is needed to determine how phenotypic flexibility during tissue remodeling and early reproductive investment translates to natural conditions and affects fitness.

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