The effect of leaf size on mutual shading and cultivar differences in soybean leaf photosynthetic capacity

The paper valuates the differences in the selected characteristics of the assimilation apparatus of beech transplants growing in various light conditions of blue spruce small pole stage in the Jizerské hory Mts. in the Czech Republic. The leaf area, chemical parameters, and photosynthetic capacity measured by the method of chlorophyll fluorescence were established. Light conditions of individual beech trees were determined by means of processing a hemisphere photograph of the crown space. The research revealed a significant trend of decreasing nitrogen content with increasing irradiance of the beech. The foliage of the sheltered beech trees exhibited higher contents of phosphorus and potassium. The average specific leaf mass (SLM) of the beech under crowns was lower (0.303 contrary to 0.499 g/dm<sup>2</sup> in gap) and the respective variants did not differ in average leaf size. A significantly higher maximum fluorescence and a maximum quantum yield (0.854 contrary to 0.803 in gap) were found under crowns. A significant variance was also observed in the absorption capacity. It follows that the beech showed adaptation to the light conditions defined by its location within the stand of blue spruce.

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Leaf morphology and photosynthetic rate in birch seedlings and stump sprouts

Canadian Journal of Forest Research ◽

10.1139/x90-128 ◽

1990 ◽

Vol 20 (7) ◽

pp. 952-960 ◽

Cited By ~ 22

Author(s):

A. Kauppi ◽

M. Kiviniitty ◽

A. Ferm

Keyword(s):

Nitrogen Content ◽

Shoot Growth ◽

Photosynthetic Capacity ◽

Leaf Size ◽

Growing Season ◽

Optimum Temperature ◽

Factors Affecting ◽

Mesophyll Structure ◽

Rate Of Photosynthesis ◽

Seed Origin

Comparisons were made of the leaves of sprout-origin and seed-origin shoots of Betulapubescens Ehrh. and B. pendula Roth grown under constant or varying temperatures. Particular attention was paid to leaf structure and other factors affecting the rate of photosynthesis. Differences in shoot growth, leaf size, mesophyll structure, and chlorophyll and nitrogen content were observed between the sprouts and seedlings of both species over the course of the growing season. Many of these differences were reflected in the photosynthesis measurements. The sprouts of both species appeared to show a better photosynthetic capacity in their first growing season than the seedlings, and they continued their height growth longer into the autumn. A distinct decline in the level of photosynthesis took place during the growing season. The results suggest that perhaps because of their higher chlorophyll and nitrogen content, young sprouts benefit more from the extremes of temperature at the beginning and end of the growing season than seedlings of the same age. The optimum temperature was the same for sprouts and seedlings of both species. Whether the superior photosynthetic capacity of sprouts compared with seedlings is maintained in later years remains to be resolved.

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Peanut Cultivar Differences in Yield Based on Source and Sink Characteristics

Jurnal Agronomi Indonesia (Indonesian Journal of Agronomy) ◽

10.24831/jai.v40i3.6825 ◽

1970 ◽

Vol 40 (3) ◽

Author(s):

Iskandar Lubis ◽

Heni Purnamawati ◽

Roedhy Poerwanto ◽

, Yudiwanti ◽

Ahmad Ghozi Mansyuri ◽

...

Keyword(s):

Growth Rate ◽

Leaf Area Index ◽

Leaf Area ◽

Photosynthetic Capacity ◽

Dry Weight ◽

Crop Growth ◽

Cultivar Differences ◽

Area Index ◽

Crop Growth Rate ◽

Single Leaf

This research was conducted to determine peanut cultivar differences in sink and source sizes as represented by vegetative growth and yields. Two sets of experiments were conducted at Bogor Agricultural University farms, Sawah Baru and Cikarawang (06o33’, S, 106o45’E, 250 m altitude). Planting was conducted on June 12 and June 20, 2007 using 20 local and national cultivars in each location. Both experiments used randomized complete block design with three replications. Data were analyzed using correlation and regression analysis. Size of experimental unit was 1.6 m x 4.0 m, with planting density 125,000 plants ha-1. Urea, SP36 and KCl were applied at planting date in the rate of (kg ha-1) 45 N, 100 P2O5 and 50 K2O. Four stages of plant growth were studied: 25 days after planting (DAP); 6 weeks after planting (WAP); 10 WAP (pod filling) and 14 WAP (harvest). Five plants were sampled at 25 DAP, two plants at 6 WAP, 10 WAP and 14 WAP, and separated into leaves, stems, roots and pods. The average yield of two experimental stations showed that Biawak cultivar had the highest yield due to relatively higher aboveground dry weight (source), pod filling percentage and maximum number of gynophor+pods (potential sink). Jepara cultivar had the lowest yield due to low pod filling percentage and potential sink, although its source was considered to be in the medium category. Above ground dry weight at 6 and 10 WAP had close relation with Crop Growth Rate (CGR) during 25 DAP-6 WAP and 6-10 WAP, and the higher CGR during those periods were more related to leaf area index than to single leaf photosynthetic capacity. Keywords: crop growth rate, pod filling percentage, leaf area index, single leaf photosynthetic capacity

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Awnedness affects grain yield and kernel weight in near-isogenic lines of durum wheat

Australian Journal of Agricultural Research ◽

10.1071/ar02008 ◽

2002 ◽

Vol 53 (12) ◽

pp. 1285 ◽

Cited By ~ 30

Author(s):

Rosella Motzo ◽

Francesco Giunta

Keyword(s):

Grain Yield ◽

Durum Wheat ◽

Photosynthetic Capacity ◽

Triticum Turgidum ◽

Flag Leaf ◽

Canopy Temperature ◽

Leaf Size ◽

Grain Filling ◽

Kernel Weight ◽

Severe Drought

The importance of awns in durum wheat (Triticum turgidum L. var. durum) has to be evaluated whenever an increase in grain yield is expected due to a greater photosynthetic capacity of the awned ear. Awned and awnless isolines of durum wheat were compared in a 3-year field trial in Sardinia (Italy). Ear and flag-leaf size, radiation interception, canopy temperature, yield, and yield components were measured.Awns increased the ear surface area from 36 to 59%, depending on their length, which ranged from 5.5 to 13.8 cm. This resulted in an average 4% more radiation intercepted by the awned ears. Canopy temperature was 0.9�C lower, on average, in the awned isolines, and was negatively correlated with kernel weight (r = –0.85**, n = 10), although consistent and marked effects of awns on canopy temperature were only observed in the long-awned lines. Awns positively affected grain yield, with an average increase of 10 and 16%, respectively, in the 2 years in which they affected kernel weight. The irrelevant effect of awns on yield in the year characterised by a severe drought was a consequence of their early desiccation.The effects of awns on grain yield and kernel weight strongly depend on the genetic background, on awn length and functionality, and on the environmental conditions during grain filling.

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Mutual shading and the photosynthetic capacity of exposed leaves of field grown soybeans

Photosynthesis Research ◽

10.1007/bf00054990 ◽

1988 ◽

Vol 15 (1) ◽

pp. 75-83 ◽

Cited By ~ 5

Author(s):

James A. Bunce

Keyword(s):

Photosynthetic Capacity ◽

Mutual Shading

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Irrigated Soybean Leaf Photosynthesis in the Humid Subtropical Midsouth

International Journal of Agronomy ◽

10.1155/2014/787945 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

H. Arnold Bruns

Keyword(s):

Stomatal Conductance ◽

Growth Stage ◽

Cultivar Differences ◽

Photon Flux ◽

Growth Stages ◽

Base Temperature ◽

Leaf Photosynthesis ◽

Photosynthetic Photon Flux ◽

Single Leaf ◽

Soybean Leaf

Photosynthesis (CER (μmol CO2mleaf area-2 s−1)), stomatal conductance (gsw), and intercellular [CO2] (Ci) of soybean (Glycine maxL. Merr.) grown using the early soybean production system (ESPS) of the midsouth were determined. Three irrigated cultivars were grown using ESPS on Bosket (Mollic Hapludalfs) and Dundee (Typic Endoaqualf) soils in 2011 and 2012 at Stoneville, MS. Single leaf CER,gsw, andCiwere determined at growth stages R3, R4, and R5 using decreasing photosynthetic photon flux densities (PPFD,μmol m−2 s−1) beginning at 2000 PPFD and decreasing by 250 PPFD increments to 250 PPFD. Photosynthesis changes fit a quadratic polynomial for all fixed variables and range from ~6.0 and 9.0 CER at 250 PPFD and ~22.0 to 28.0 CER at 2000 PPFD. No cultivar differences in CER,gsw, orCiwere noted at any growth stage or site either year. In 2012, CER,gsw, andCiwere lower when measured at R5 than the two previous growth stages, which was not observed in 2011. The R5 sampling in 2012 had accumulated 39 to 70 more growing degree units at 10°C base temperature (GDU 10’s) than in 2011 and were likely more mature. Increased soybean yields from ESPS appear not to result from higher leaf CER.

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Leaf Anatomy, Morphology and Photosynthesis of Three Tundra Shrubs after 7-Year Experimental Warming on Changbai Mountain

Plants ◽

10.3390/plants8080271 ◽

2019 ◽

Vol 8 (8) ◽

pp. 271

Author(s):

Yumei Zhou ◽

Jifeng Deng ◽

Zhijuan Tai ◽

Lifen Jiang ◽

Jianqiu Han ◽

...

Keyword(s):

Climate Warming ◽

Photosynthetic Capacity ◽

Leaf Size ◽

Vaccinium Uliginosum ◽

Growing Seasons ◽

Dryas Octopetala ◽

Tundra Ecosystem ◽

Soil Temperatures ◽

Species Specific ◽

Warming World

Tundra is one of the most sensitive biomes to climate warming. Understanding plant eco-physiological responses to warming is critical because these traits can give feedback on the effects of climate-warming on tundra ecosystem. We used open-top chambers following the criteria of the International Tundra Experiment to passively warm air and soil temperatures year round in alpine tundra. Leaf size, photosynthesis and anatomy of three dominant species were investigated during the growing seasons after 7 years of continuous warming. Warming increased the maximal light-saturated photosynthetic rate (Pmax) by 43.6% for Dryas. octopetala var. asiatica and by 26.7% for Rhododendron confertissimum across the whole growing season, while warming did not significantly affect the Pmax of V. uliginosum. The leaf size of Dr. octopetala var. asiatica and Rh. confertissimum was increased by warming. No marked effects of warming on anatomical traits of Dr. octopetala var. asiatica were observed. Warming decreased the leaf thickness of Rh. confertissimum and Vaccinium uliginosum. This study highlights the species-specific responses to climate warming. Our results imply that Dr. octopetala var. asiatica could be more dominant because it, mainly in terms of leaf photosynthetic capacity and size, seems to have advantages over the other two species in a warming world.

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