Effects of Simulated Defoliation on Growth and Photosynthetic Characteristics of an Invasive Liana, Ipomoea cairica (Convolvulaceae)

2012 ◽  
Vol 5 (2) ◽  
pp. 282-289 ◽  
Author(s):  
Weihua Li ◽  
Xingshan Tian ◽  
Jianning Luo ◽  
Yanhong Dai ◽  
Changlian Peng
Keyword(s):  
Compensatory Growth ◽  
Plant Biomass ◽  
Photosynthetic Characteristics ◽  
Leaf Biomass ◽  
Total Biomass ◽  
Stomatal Limitation ◽  
Simulated Herbivory ◽  
Energy Dissipated ◽  
Simulated Defoliation ◽  
Uptake Of Nutrients

AbstractTo better understand the response of Ipomoea cairica (Cairo morningglory) to herbivory, the compensatory growth and photosynthetic characteristics of plants were measured after simulated herbivory by leaf trimming at four intensities: 25, 50, 75, and 100% removal, starting from the apex. Defoliation at 25% had no significant influence on plant biomass, but the total biomass (−19 to −66%) and root biomass (−31 to −75%) of the plants decreased significantly when defoliation intensity was ≥ 50% (P < 0.05). Photosynthetic rates (Pn) increased with defoliation intensity (P < 0.01), and Pn values in the defoliated plants were 10 to 72% greater than those in the control plants, a relationship that could be attributed to a decrease in stomatal limitation (−11 to −34%) and the increase in rubisco content (9 to 18%) as well as higher photosynthetic efficiency and less light energy dissipated as heat. At defoliation intensities up to 50%, plants needed more energy to compensate photosynthetically, which could influence the plant photosynthetic characteristics as well as the allocation of assimilates, resulting in less root development. Since the spread of I. cairica depends primarily on clonal growth, smaller roots could limit uptake of nutrients from the soil. These direct and indirect effects indicate that leaf-feeding herbivores may have potential for biological control of I. cairica but to have any effect the herbivores would need to consume ≥ 50% of the leaf biomass.

scholarly journals Influence of Simulated Defoliation and N Fertilization on Compensatory Growth of Gmelina arborea Seedlings

2020 ◽  
pp. 59-66
Author(s):  
Titus Fondo Ambebe ◽  
Anjah Grace Mendi ◽  
Abubakar Ali Shidiki
Keyword(s):  
Compensatory Growth ◽  
Interactive Effect ◽  
N Fertilization ◽  
Stem Volume ◽  
Total Biomass ◽  
N Availability ◽  
Gmelina Arborea ◽  
Leaf Production ◽  
Increasing Trend ◽  
Simulated Defoliation

To investigate the effect of artificial defoliation and N availability on growth of Gmelina arborea, seedlings were subjected to three artificial defoliation levels (0, 25, 50%) and four N regimes (unfertilized, 1 g N plant-1, 3 g N plant-1, 6 g N plant-1) in a field trial. The results showed that height increment was 24.09% lower in the 50% defoliation than the undefoliated and 25% defoliation treatments which were not significantly different from each other. On average, the 25% and 50% defoliation treatments reduced stem volume increment by 44.34%. Increments of diameter and biomass and leaf production were not reduced by defoliation. In terms of response to N, increments in height and stem volume rose from 8.98 cm and 8.23 mm at unfertilized  to 11.39 cm and 12.13 mm at 3 g N plant-1, respectively, while number of new leaves increased by a margin of 1.51 from unfertilized to  6 g N plant-1. Total biomass increment that was unaffected by defoliation showed an increasing trend from 0.55 g at unfertilized and 1 g N to 0.83 g at 3 g N and 0.94 g at 6 g N plant-1. There was no significant interactive effect of treatments on any parameter, suggesting that the adverse effect of defoliation on growth of G. arborea seedlings may not be alleviated by N fertilization. It is encouraged that a similar study be conducted for a longer duration to ascertain if the responses are sustained or modified.

Effects of CO2 enrichment and nutrition on growth, photosynthesis, and nutrient concentration of Alaskan tundra plant species

1986 ◽  
Vol 64 (12) ◽  
pp. 2993-2998 ◽  
Author(s):  
Steven F. Oberbauer ◽  
Nasser Sionit ◽  
Steven J. Hastings ◽  
Walter C. Oechel
Keyword(s):  
Plant Biomass ◽  
Co2 Enrichment ◽  
Nutrient Content ◽  
Interactive Effects ◽  
Photon Flux ◽  
Nutrient Concentrations ◽  
Total Biomass ◽  
Ledum Palustre ◽  
Carbon Dioxide Concentrations ◽  
Alaskan Tundra

Three Alaskan tundra species, Carex bigelowii Torr., Betula nana L., and Ledum palustre L., were grown in controlled-environment chambers at two nutrition levels with two concentrations of atmospheric CO2 to assess the interactive effects of these factors on growth, photosynthesis, and tissue nutrient content. Carbon dioxide concentrations were maintained at 350 and 675 μL L−1 under photosynthetic photon flux densities of 450 μmol m−2 s−1 and temperatures of 20:15 °C (light:dark). Nutrient treatments were obtained by watering daily with 1/60- or 1/8- strength Hoagland's solution. Leaf, root, and total biomass were strongly enhanced by nutrient enrichment regardless of the CO2 concentration. In contrast, enriched atmospheric CO2 did not significantly affect plant biomass and there was no interaction between nutrition and CO2 concentration during growth. Leaf photosynthesis was increased by better nutrition in two species but was unchanged by CO2 enrichment during growth in all three species. The effects of nutrient addition and CO2 enrichment on tissue nutrient concentrations were complex and differed among the three species. The data suggest that CO2 enrichment with or without nutrient limitation has little effect on the biomass production of these three tundra species.

scholarly journals The significance of biomass allocation to population growth of the invasive species Ambrosia artemisiifolia and Ambrosia trifida with different densities

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wenxuan Zhao ◽  
Tong Liu ◽  
Yan Liu ◽  
Hanyue Wang ◽  
Ruili Wang ◽  
...  
Keyword(s):  
Cluster Formation ◽  
Ambrosia Artemisiifolia ◽  
High Density ◽  
High Population ◽  
Leaf Biomass ◽  
Total Biomass ◽  
Low Density ◽  
Population Densities ◽  
Ambrosia Trifida ◽  
Short Period

Abstract Background Ambrosia artemisiifolia and Ambrosia trifida are globally distributed harmful and invasive weeds. High density clusters play an important role in their invasion. For these two species, the early settled populations are distributed at low densities, but they can rapidly achieve high population densities in a short period of time. However, their response to intraspecific competition to improve the fitness for rapid growth and maintenance of high population densities remains unclear. Therefore, to determine how these species form and maintain high population densities, individual biomass allocations patterns between different population densities (low and high), and plasticity during seedling, vegetative, breeding and mature stages were compared. In 2019, we harvested seeds at different population densities and compared them, and in 2020, we compared the number of regenerated plants across the two population densities. Results Most biomass was invested in the stems of both species. Ambrosia trifida had the highest stem biomass distribution, of up to 78%, and the phenotypic plasticity of the stem was the highest. Path analysis demonstrated that at low-density, total biomass was the biggest contributor to seed production, but stem and leaf biomass was the biggest contributors to high-density populations. The number of seeds produced per plant was high in low-density populations, while the seed number per unit area was huge in high-density populations. In the second year, the number of low-density populations increased significantly. A. artemisiifolia and A. trifida accounted for 75.6% and 68.4% of the mature populations, respectively. Conclusions High input to the stem is an important means to regulate the growth of the two species to cope with different densities. These two species can ensure reproductive success and produce appropriate seed numbers. Therefore, they can maintain a stable population over time and quickly form cluster advantages. In the management, early detection of both species and prevention of successful reproduction by chemical and mechanical means are necessary to stop cluster formation and spread.

scholarly journals Severe Water Deficiency during the Mid-Vegetative and Reproductive Phase has Little Effect on Proso Millet Performance

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2155 ◽  
Author(s):  
Grašič ◽  
Golob ◽  
Vogel-Mikuš ◽  
Gaberščik
Keyword(s):  
Crop Production ◽  
Plant Biomass ◽  
Leaf Traits ◽  
Water Shortage ◽  
Short Wave ◽  
Leaf Biomass ◽  
Yield Reduction ◽  
Water Deficiency ◽  
Negative Effects ◽  
Proso Millet

Climate change can result in extreme droughts, significantly affecting crop production. C4 crop proso millet (Panicum miliaceum L.) has the lowest water consumption among all of the cereal crops. Understanding its survival mechanisms is thus crucial for agriculture. Furthermore, yield reduction does not only occur directly due to water shortage, but is also a consequence of an impaired element uptake during drought. This study aimed to examine the effect of water deficiency on proso millet leaf traits, plant biomass partition, and yield. In addition, leaf element contents were analysed, including silicon, which is an important multifunctional element for grasses. The majority of the measured parameters showed little change from the control to the moderate and severe water shortage treatments, even though the soil moisture levels differed significantly. The most pronounced reduction in comparison to the control was for leaf biomass, leaf stomatal conductance, and leaf silicon, phosphorus, calcium, and sulphur contents. Conversely, an increase was obtained for leaf potassium and chlorine contents. Panicle biomass was the same for all plant groups. Leaf silicon was positively correlated to reflectance in the UV region, while leaf calcium was negatively correlated to reflectance in the visible regions, which might prevent damage due to short-wave UV radiation and provide sufficient visible light for photosynthesis. The efficient light and water management, reduction of leaf biomass, and same-sized root system may be the mechanisms that mitigate the negative effects of water shortage in proso millet.

scholarly journals Evaluation of Chickpea (Cicer arietinum L.) Genotypes for Quality Seedlings

1970 ◽  
Vol 8 (2) ◽  
pp. 108-116
Author(s):  
Shahrina Akhtar ◽  
Jalal Uddin Ahmed ◽  
Abdul Hamid ◽  
Md Rafiqul Islam
Keyword(s):  
Biomass Production ◽  
Plant Biomass ◽  
Function Analysis ◽  
Dominant Role ◽  
Seedling Emergence ◽  
Genotypic Variation ◽  
Dry Weight ◽  
Total Biomass ◽  
Maximum Variance ◽  
Total Dry Weight

A study was conducted to evaluate 100 chickpea genotypes to explore their genetic diversity in respect of emergence and growth attributes. A high genotypic variation was observed in the characters studied. The highest positive correlation corresponded to the root mass and total plant biomass of the seedlings. Seedling biomass production was highly subjective to seedling vigor. Using discriminant function analysis, the first two functions contributed 46.2 and 39.0%, and altogether 85.2% of the variability among the genotypes. Function 1 was positively related to dry weight of root and total plants. The character with the greatest weight on function 2 was seedling emergence rate. The total dry weight of seedlings played the most dominant role in explaining the maximum variance in the genotypes. The genotypes were grouped into six clusters. Each cluster had specific seedling characteristics and the clusters 5 and 6 were closely related and clearly separated from clusters 1 and 4 for their higher amount of root and total biomass production, and vigorous seedlings, where as, the genotypes in cluster 2 and 3 were intermediate. The genotypes in cluster 5 followed by cluster 6 appeared to be important resources for selecting and developing chickpea variety. Keywords: Chickpea; genotypes; seedling; quality DOI: 10.3329/agric.v8i2.7584 The Agriculturists 8(2): 108-116 (2010)

Comparison of teosinte (Zea mexicana L.) and inter-subspecific hybrids (Zea mays L.×Zea mexicana) for high forage yield under two sowing regimes

2015 ◽  
Vol 66 (1) ◽  
pp. 49 ◽  
Author(s):  
Imtiaz Akram Khan Niazi ◽  
Saeed Rauf ◽  
Jaime A. Teixeira da Silva ◽  
Hassan Munir
Keyword(s):  
Zea Mays ◽  
Heat Stress ◽  
Zea Mays L ◽  
Agronomic Traits ◽  
Plant Biomass ◽  
Stress Conditions ◽  
Forage Yield ◽  
Total Biomass ◽  
Percentage Survival ◽  
Biomass Plant

This study was undertaken to evaluate the response of teosinte (Zea mexicana L.) and intersubspecific hybrids to heat stress, in particular productivity. Unlike maize (Zea mays L.), teosinte demonstrated thermophilic properties, namely lower heat injury, sustained chlorophyll content under heat stress (36−45°C) and high percentage survival of seedlings (at 55°C). Teosinte also had the ability to produce large plant biomass (27% and 55% higher yield than maize under non-stressed and stress conditions, respectively) and therefore could be exploited as a forage crop. However, teosinte forage had low animal intake (1.48 kg day–1) because of high pubescence density (10.38 view–1) and low sweetness (9.90°Brix). There was a high percentage of heterosis in variable intersubspecific crosses and traits, and a high magnitude of over-dominance for many traits, for example 5.93–7.06 for total biomass plant–1. Hybrids showed additional advantages, including high oil (20% and 4%) and protein (14% and 25%) contents compared with teosinte under non-stressed and stress conditions, respectively. Moreover, inter-subspecific hybrids were also resistant to heat stress, with the capacity for sustaining growth for a longer period (20% and 33% higher than maize under non-stressed and stress conditions, respectively). Genetic distance between parents—calculated from stable agronomic traits—could be used to select parents for high heterosis under both heat stress and non-stressed conditions.

Relationship between changes in photosynthetic characteristics and plant compensatory growth under different sand burial depths

2016 ◽  
Vol 36 (24) ◽  
Author(s):  
周瑞莲 ZHOU Ruilian ◽  
贾有余 JIA Youyu ◽  
侯月利 HOU Yueli ◽  
石琳琳 SHI Linlin
Keyword(s):  
Compensatory Growth ◽  
Photosynthetic Characteristics ◽  
Sand Burial

Natural variation in common bean (Phaseolus vulgaris L.) for root traitsand biomass partitioning under drought

2016 ◽  
Vol 50 (6) ◽  
Author(s):  
Parvaze A. Sofi ◽  
Iram Saba
Keyword(s):  
Common Bean ◽  
Root Traits ◽  
Dry Weight ◽  
Biomass Partitioning ◽  
Rooting Depth ◽  
Leaf Biomass ◽  
Root Weight ◽  
Total Biomass ◽  
Phaseolus Vulgaris L ◽  
Shoot Dry Weight

The present study was undertaken to assess the response of common bean under drought in respect of root traits and biomass partitioning in fifteen common bean genotypes. The basal root whorl number and the number of basal roots was highest in case of WB-185 and lowest in case of SR-1, whereas, the basal root growth angle was highest in case of WB-258 and lowest in case of WB-249. Rooting depth measured as the length of longest root harvested was highest in case of WB-6 (66.2) while as lowest value was recorded for WB-112 (20.4). Dry root weight was highest in case of WB-216 (0.45) and lowest value was recorded for WB-341 (0.22). Similarly leaf biomass was highest in case of WB-6 (0.58) followed by WB-216 (0.58) and the lowest value recorded for WB-1186 (0.12). Shoot dry weight was highest for WB-6 (0.55) followed by WB-216 (0.44) and the lowest value recorded for WB-1186 (0.118). Pod dry weight was highest for WB-489 (2.28) followed by WB-216 (2.19) and the lowest value recorded for WB-83 (0.68).489. Root biomass proportion was highest for WB-195 (18.34) and lowest for WB-489 (10.00). Similarly leaf biomass to total biomass was highest in case of WB-83 (23.19) whereas lowest value was recorded for WB-1186 (7.60). Highest stem biomass proportion was recorded for Arka Anoop (19.19) and the lowest value was recorded for WB-1186 (7.591). Biomass allocation to pods was highest in case of WB-489 (69.92) followed by WB-1186 (68.69) whereas lowest value was recorded for WB-83 (45.40).

Rhizobial inoculant formulations and soil pH influence field pea nodulation and nitrogen fixation

2000 ◽  
Vol 80 (3) ◽  
pp. 395-400 ◽  
Author(s):  
W. A. Rice ◽  
G. W. Clayton ◽  
P. E. Olsen ◽  
N. Z. Lupwayi
Keyword(s):  
Nitrogen Content ◽  
Soil Ph ◽  
Crop Production ◽  
Plant Biomass ◽  
Acid Soil ◽  
Dry Weight ◽  
Field Pea ◽  
Total Biomass ◽  
Plant Nitrogen ◽  
Liquid Inoculant

Crop production systems that include field pea (Pisum sativum L.) in rotation are important for sustainable agriculture on acid soils in northwestern Canada. Greenhouse experiments were conducted to compare the ability of liquid inoculant applied to the seed, powdered peat inoculant applied to the seed, and granular inoculant applied in a band with the seed to establish effective nodulation on field pea grown at soil pH(H2O) 4.4, 5.4 and 6.6. Plants were grown to the flat pod stage, and then total plant biomass dry weight, dry weight of nodules, number of nodules, plant nitrogen content, and proportion of plant nitrogen derived from the atmosphere (%Ndfa) were measured. Granular and powdered peat inoculants produced greater nodule numbers and weight, plant nitrogen content, %Ndfa and total biomass than liquid inoculant in at least two of the three experiments. Only granular inoculant was effective in establishing nodules at soil pH 4.4, but granular and powdered peat inoculants were effective at pH 5.4, and all three formulations were effective at pH 6.6. The results showed that granular inoculant has potential for effective nodulation of field pea grown on acid soil. Key words: Rhizobium, inoculant formulations, field pea, nodulation, acid soil

Sign in / Sign up

Export Citation Format

Share Document