Effects of frost on shaded and exposed spruce and pine seedlings planted in the field

1987 ◽  
Vol 17 (10) ◽  
pp. 1197-1201 ◽  
Author(s):  
Tomas Lundmark ◽  
Jan-Erik Hällgren
Keyword(s):  
Solar Radiation ◽  
Soil Water ◽  
Chlorophyll Concentration ◽  
Growing Season ◽  
High Irradiance ◽  
Northern Sweden ◽  
Photosynthetic Rates ◽  
Pine Seedlings ◽  
Similar Temperature ◽  
Radiant Load

Spruce (Piceaabies L.) and pine (Pinussylvestris L.) seedlings were planted at different positions relative to artificial tree shades. Two sites in northern Sweden known as difficult to regenerate owing to frosts during the growing season were used. No deficiency of soil water was recorded during the growing season and all seedlings experienced similar temperature conditions during night frosts. Exposed seedlings received on clear days 7 h more of direct solar radiation than did shaded seedlings. After the first severe night frost in August, discoloration of needles and a decrease in chlorophyll concentration as well as lowered photosynthetic rates were more pronounced for the exposed seedlings. This was more obvious for spruce than pine seedlings. The differences in radiant load seem to be of ultimate importance for the results observed. It is proposed that photoinhibition and subsequent photooxidation of planted seedlings occur in the field when severe night frosts are followed by clear days with high irradiance.

scholarly journals Characterizing Growing Season Length of Subtropical Coniferous Forests with a Phenological Model

Forests ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 95
Author(s):  
Yuan Gong ◽  
Christina L. Staudhammer ◽  
Susanne Wiesner ◽  
Gregory Starr ◽  
Yinlong Zhang
Keyword(s):  
Climate Change ◽  
Soil Water ◽  
Prescribed Fire ◽  
Water Availability ◽  
Longleaf Pine ◽  
Growing Season ◽  
Soil Water Availability ◽  
Future Climate Change ◽  
Short Term ◽  
Phenological Model

Understanding plant phenological change is of great concern in the context of global climate change. Phenological models can aid in understanding and predicting growing season changes and can be parameterized with gross primary production (GPP) estimated using the eddy covariance (EC) technique. This study used nine years of EC-derived GPP data from three mature subtropical longleaf pine forests in the southeastern United States with differing soil water holding capacity in combination with site-specific micrometeorological data to parameterize a photosynthesis-based phenological model. We evaluated how weather conditions and prescribed fire led to variation in the ecosystem phenological processes. The results suggest that soil water availability had an effect on phenology, and greater soil water availability was associated with a longer growing season (LOS). We also observed that prescribed fire, a common forest management activity in the region, had a limited impact on phenological processes. Dormant season fire had no significant effect on phenological processes by site, but we observed differences in the start of the growing season (SOS) between fire and non-fire years. Fire delayed SOS by 10 d ± 5 d (SE), and this effect was greater with higher soil water availability, extending SOS by 18 d on average. Fire was also associated with increased sensitivity of spring phenology to radiation and air temperature. We found that interannual climate change and periodic weather anomalies (flood, short-term drought, and long-term drought), controlled annual ecosystem phenological processes more than prescribed fire. When water availability increased following short-term summer drought, the growing season was extended. With future climate change, subtropical areas of the Southeastern US are expected to experience more frequent short-term droughts, which could shorten the region’s growing season and lead to a reduction in the longleaf pine ecosystem’s carbon sequestration capacity.

Early growth of lodgepole pine after establishment of alsike clover–Rhizobium nitrogen-fixing symbiosis

1992 ◽  
Vol 22 (8) ◽  
pp. 1089-1093 ◽  
Author(s):  
R. Trowbridge ◽  
F.B. Holl
Keyword(s):  
Forest Floor ◽  
Lodgepole Pine ◽  
Nitrogen Concentration ◽  
Growing Season ◽  
Early Growth ◽  
Percent Cover ◽  
Foliar Nitrogen ◽  
Growing Seasons ◽  
Pine Seedlings ◽  
Needle Mass

An overdense lodgepole pine (Pinuscontorta Dougl. ex Loud.) stand was knocked down and the site was prepared by broadcast burn, windrow burn, or mechanical forest floor removal. Inoculated alsike clover (Trifoliumhybridum L.) was seeded at 0, 10, 20, and 30 kg/ha for the three different site preparation treatments to determine the effects of (i) site preparation on infection and effectiveness of the clover–Rhizobium symbiosis and clover percent cover and (ii) the clover–Rhizobium N2-fixing symbiosis on survival, early growth, and foliar nitrogen concentration of lodgepole pine seedlings. The N2-fixing symbiosis established well in all treatments. Clover percent cover increased with increasing rate of seeding, although by relatively few percent in the clover seeded plots. Broadcast burning, windrow burning, and mechanical forest floor removal did not affect the establishment of the N2-fixing symbiosis or clover percent cover. Lodgepole pine survival was not affected by the seeding treatments in any year, nor were height measurements during the first three growing seasons. Seedling height was slightly less in clover-seeded plots compared with controls in the fourth growing season. Lodgepole pine seedlings on clover-seeded plots had decreased diameter growth compared with controls during the first three growing seasons, but incremental diameter growth no longer showed this effect by the fourth growing season. Needle mass (g/100 needles) was less in clover-seeded plots at the end of the second growing season, but this effect was reversed by the fourth growing season, when both needle mass and foliar nitrogen concentration in lodgepole pine foliage were greater in clover-seeded plots.

Soil water retention dynamics in a Mollisol during a maize growing season under contrasting tillage systems

2021 ◽  
Vol 209 ◽  
pp. 104953
Author(s):  
Xinjun Huang ◽  
Hengfei Wang ◽  
Meng Zhang ◽  
Rainer Horn ◽  
Tusheng Ren
Keyword(s):  
Soil Water ◽  
Water Retention ◽  
Growing Season ◽  
Soil Water Retention ◽  
Tillage Systems

scholarly journals Protective Netting Improves Leaf-level Photosynthetic Light Use Efficiency in ‘Honeycrisp’ Apple Under Heat Stress

HortScience ◽  
2018 ◽  
Vol 53 (10) ◽  
pp. 1416-1422 ◽  
Author(s):  
Giverson Mupambi ◽  
Stefano Musacchi ◽  
Sara Serra ◽  
Lee A. Kalcsits ◽  
Desmond R. Layne ◽  
...  
Keyword(s):  
Heat Stress ◽  
Solar Radiation ◽  
Leaf Gas Exchange ◽  
Growing Season ◽  
High Light ◽  
Weather Data ◽  
Light Use Efficiency ◽  
Ambient Temperatures ◽  
Leaf Level ◽  
Use Efficiency

Globally, apple production often occurs in semiarid climates characterized by high summer temperatures and solar radiation. Heat stress events occur regularly during the growing season in these regions. For example, in the semiarid eastern half of Washington State, historic weather data show that, on average, 33% of the days during the growing season exceed 30 °C. To mediate some of the effects of heat stress, protective netting (PN) can be used to reduce the occurrence of fruit sunburn. However, the impacts of reduced solar radiation in a high light environment on light-use efficiency and photosynthesis are poorly understood. We sought to understand the ecophysiological response of apple (Malus domestica Borkh. cv. Honeycrisp) under blue photoselective PN during days with low (26.6 °C), moderate (33.7 °C), or high (38.1 °C) ambient temperatures. Two treatments were evaluated; an uncovered control and blue photoselective PN. Maximum photochemical efficiency of PSII, or photosystem II (Fv/Fm) was significantly greater at all measurement times under blue photoselective PN compared with the control on days with high ambient temperatures. Fv/Fm dropped below 0.79, which is considered the threshold for stress, at 1000 hr in the control and at 1200 hr under blue photoselective PN on a day with high ambient temperature. On days with low or moderate ambient temperatures, Fv/Fm was significantly greater under blue photoselective PN at 1400 hr, which coincided with the peak in solar radiation. ‘Honeycrisp’ apple exhibited dynamic photoinhibition as shown by the diurnal decline in Fv/Fm. Quantum photosynthetic yield of PSII (ΦPSII) was also generally greater under blue photoselective PN compared with the control for days with moderate or high ambient temperatures. Photochemical reflectance index (ΔPRI), the difference in reflectance between a stress-responsive and nonstress-responsive wavelength, was greater under PN compared with the control on the day with high ambient temperatures, with no differences observed under low or moderate ambient temperatures. Leaf gas exchange did not show noticeable improvement under blue photoselective netting when compared with the control despite the improvement in leaf-level photosynthetic light use efficiency. In conclusion, PN reduced incoming solar radiation, improved leaf-level photosynthetic light use efficiency, and reduced the symptoms of photoinhibition in a high-light, arid environment.

scholarly journals ACCUMULATION BEHAVIOUR OF ALLANTOIN IN THE UNDERGROUND PHYTOMASS OF THE BORAGINACEAE FAMILY AND ITS ROLE IN ADAPTING THE PLANTS TO ADVERSE ENVIRONMENTAL FACTORS

2019 ◽  
Vol 14 (1) ◽  
pp. 126-136
Author(s):  
A. Ya. Tamakhina ◽  
A. A. Akhkubekova ◽  
A. B. Ittiev
Keyword(s):  
Solar Radiation ◽  
Sea Level ◽  
Low Temperatures ◽  
High Performance ◽  
Growing Season ◽  
Stress Factors ◽  
Adaptation To Stress ◽  
Plant Adaptation ◽  
The Family

Aim.The aim of the work described herein was to study the dynamics of allantoin accumulation in the underground phytomass ofEchium vulgareL.,Symphytum caucasicumM. Bieb. andS. asperumLepech. as well as to clarify the role of allantoin in plant adaptation to stress factors.Methods.We studied the roots of plants growing in the foothill (Nalchik, 490–512 m above sea level) and the mountain zones of the Kabardino-Balkarian Republic (Terskol village, 2530 m above sea level; Verkhnyaya Balkaria village, 2680 m above sea level). The roots were collected at the stages of rosetting, flowering, fruiting and at the end of the growing season. Aqueous-alcoholic extracts of shredded roots were analyzed by high-performance liquid chromatography.Results.The highest content of allantoin in the roots ofEchium vulgare,Symphytum caucasicum,S. asperumplants was noted at the end of the growing season, respectively 0.915; 0.342–0.658; 2,842–3,426%. Under conditions of low temperatures and increased solar radiation, the content of allantoin in the roots increases 1.2–1.9 times as compared with the plants of the foothill zone.Conclusion.Allantoin plays an important role in the process of adapting species of the family Boraginaceae to oxidative stress caused by hypothermia and increased solar radiation.

Nitrate metabolism in Scots pine seedlings during their first growing season

1987 ◽  
Vol 3 (3) ◽  
pp. 285-293 ◽  
Author(s):  
T. Sarjala ◽  
R. Raitio ◽  
E.-M. Turkki
Keyword(s):  
Scots Pine ◽  
Growing Season ◽  
Pine Seedlings ◽  
Nitrate Metabolism

Nursery Fertilization and Top Pruning of Slash Pine Seedlings

1990 ◽  
Vol 14 (2) ◽  
pp. 73-76 ◽  
Author(s):  
Mary L. Duryea
Keyword(s):  
Crop Yield ◽  
Field Performance ◽  
Growing Season ◽  
Height Growth ◽  
Slash Pine ◽  
Shoot Height ◽  
Foliar Nitrogen ◽  
N Concentration ◽  
Pine Seedlings

Abstract Top pruning, growing-season fertilization, and fall fertilization were investigated in a Florida nursery to determine the effects on crop yield, morphology, nutrition, and field performance. Top pruning improved crop yield by reducing the number of cull seedlings. Top-pruned seedlings were smaller in diameter, height, and weight and had an increased number of multiple tops. In the field, top-pruned seedlings had the same survival and height growth, and after 3 years the percentage with multiple tops was the same as nonpruned seedlings. From these results, top pruning seems to be a nondetrimental practice for controlling height and producing a uniform crop in the nursery. Reducing growing-season fertilization slightly decreased shoot height, but not as much as top pruning. Also, these seedlings had reduced foliar nitrogen (N) concentration and content and grew less after 1 year in the field indicating that cutting back on N in the nursery may not be a beneficial way to control height. Fall fertilization in the nursery increased N in seedlings but did not affect growth or survival in the field. South. J. Appl. For. 14(2):73-76.

Sign in / Sign up

Export Citation Format

Share Document