FRUIT DEVELOPMENT IN DECIDUOUS TREE CROPS AS AFFECTED BY PHYSIOLOGICAL FACTORS AND ENVIRONMENTAL CONDITIONS (KEYNOTE)

2004 ◽  
pp. 425-441 ◽  
Author(s):  
L. Corelli-Grappadelli ◽  
A.N. Lakso
Keyword(s):  
Environmental Conditions ◽  
Fruit Development ◽  
Deciduous Tree ◽  
Physiological Factors ◽  
Tree Crops

The ecology of terricolous lichens of the Northern Conifer – Hardwood forests of central Eastern Canada

1968 ◽  
Vol 46 (8) ◽  
pp. 1043-1078 ◽  
Author(s):  
J. D. H. Lambert ◽  
P. F. Maycock
Keyword(s):  
Environmental Conditions ◽  
Ground Level ◽  
Hardwood Forests ◽  
Deciduous Tree ◽  
Eastern Canada ◽  
Central Canada ◽  
Terricolous Lichens ◽  
Moisture Conditions ◽  
Tree Composition ◽  
Lichen Growth

A quantitative analysis of the terricolous (ground) lichens in the Northern Conifer – Hardwood forests of central Canada is presented. Seventy-one forest stands were sampled to determine the composition of the tree and lichen strata. Tree composition was expressed in terms of a series of importance values determined from measures of frequency, density, and dominance on a relative basis, with the importance values for all trees in a stand totalling 300. A statistical analysis of lichen distribution showed that while lichens reacted in a similar manner to moisture conditions as the trees they were more commonly found in stands on dry sites. An ordination of stands indicated that optimum environmental conditions for lichen growth were found in dry young conifer stands of low absolute dominance with fairly open canopies, with slowly decomposing ground litter of decidedly acidic reaction.The increase of deciduous tree species in the mesic segments of the moisture gradient produced environmental conditions unsuitable for most of the lichen species recorded. The reduced occurrence of lichens in such sites was interpreted as being related to the lack of suitable substrates, reduction in light intensity at ground level, increased litter, and a more rapid turnover of organic matter.

scholarly journals Quantitative genetic architecture of adaptive phenology traits in the deciduous tree, Populus trichocarpa (Torr. & Gray)

2020 ◽  
Author(s):  
Thomas J Richards ◽  
Almir Karacic ◽  
Rami-Petteri Apuli ◽  
Martin Weih ◽  
Pär K. Ingvarsson ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Climate Adaptation ◽  
Populus Trichocarpa ◽  
Genetic Correlations ◽  
Deciduous Tree ◽  
Climate Projections ◽  
Bud Burst ◽  
Heritable Variation ◽  
Quantitative Genetic ◽  
Tree Survival

ABSTRACTIn a warming climate, the ability to accurately predict and track shifting environmental conditions will be fundamental for plant survival. Environmental cues define the transitions between growth and dormancy as plants synchronise development with favourable environmental conditions, however these cues are predicted to change under future climate projections which may have profound impacts on tree survival and growth. Here, we use a quantitative genetic approach to estimate the genetic basis of spring and autumn phenology in Populus trichocarpa to determine this species capacity for climate adaptation. We measured bud burst, leaf coloration, and leaf senescence traits across two years (2017-2018) and combine these observations with measures of lifetime growth to determine how genetic correlations between phenology and growth may facilitate or constrain adaptation. Timing of transitions differed between years, although we found strong cross year genetic correlations in all traits, suggesting that genotypes respond in consistent ways to seasonal cues. Spring and autumn phenology were correlated with lifetime growth, where genotypes that burst leaves early and shed them late had the highest lifetime growth. We also identified substantial heritable variation in the timing of all phenological transitions (h2 = 0.5-0.8) and in lifetime growth (h2 = 0.8). The combination of abundant additive variation and favourable genetic correlations in phenology traits suggests that cultivated varieties of P. trichocarpa have the capability to create populations which may adapt their phenology to climatic changes without negative impacts on growth.

scholarly journals Quantitative genetic architecture of adaptive phenology traits in the deciduous tree, Populus trichocarpa (Torr. and Gray)

Heredity ◽  
2020 ◽  
Vol 125 (6) ◽  
pp. 449-458 ◽  
Author(s):  
Thomas J. Richards ◽  
Almir Karacic ◽  
Rami-Petteri Apuli ◽  
Martin Weih ◽  
Pär K. Ingvarsson ◽  
...  
Keyword(s):  
Environmental Conditions ◽  
Climate Adaptation ◽  
Populus Trichocarpa ◽  
Genetic Correlations ◽  
Deciduous Tree ◽  
Climate Projections ◽  
Bud Burst ◽  
Heritable Variation ◽  
Quantitative Genetic ◽  
Tree Survival

Abstract In a warming climate, the ability to accurately predict and track shifting environmental conditions will be fundamental for plant survival. Environmental cues define the transitions between growth and dormancy as plants synchronise development with favourable environmental conditions, however these cues are predicted to change under future climate projections which may have profound impacts on tree survival and growth. Here, we use a quantitative genetic approach to estimate the genetic basis of spring and autumn phenology in Populus trichocarpa to determine this species capacity for climate adaptation. We measured bud burst, leaf coloration, and leaf senescence traits across two years (2017–2018) and combine these observations with measures of lifetime growth to determine how genetic correlations between phenology and growth may facilitate or constrain adaptation. Timing of transitions differed between years, although we found strong cross year genetic correlations in all traits, suggesting that genotypes respond in consistent ways to seasonal cues. Spring and autumn phenology were correlated with lifetime growth, where genotypes that burst leaves early and shed them late had the highest lifetime growth. We also identified substantial heritable variation in the timing of all phenological transitions (h2 = 0.5–0.8) and in lifetime growth (h2 = 0.8). The combination of additive variation and favourable genetic correlations in phenology traits suggests that populations of cultivated varieties of P. Trichocarpa may have the capability to adapt their phenology to climatic changes without negative impacts on growth.

scholarly journals Selection-Enriched Genomic Loci (SEGL) Reveals Genetic Loci for Environmental Adaptation and Photosynthetic Productivity in Chlamydomonas reinhardtii.

2021 ◽  
Author(s):  
Ben Franklin Lucker ◽  
Nicolas Panchy ◽  
Joshua Temple ◽  
Urs Benning ◽  
Jacob Bibik ◽  
...  
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Environmental Conditions ◽  
Multiple Time ◽  
Environmental Isolates ◽  
Physiological Factors ◽  
Photosynthetic Productivity ◽  
Complex Interactions ◽  
Fluctuating Light ◽  
Improved Performance ◽  
Multiple Time Points

This work demonstrates an approach to produce and select hybrid algal strains exhibiting increased photosynthetic productivity under multiple environmental conditions. This simultaneously addresses two major impediments to improving algal bioenergy production: 1) generating new genetic variants with improved performance; and 2) disentangling complex interactions between genetic and physiological factors contributing to these improvements. We pooled progeny generated from mating two environmental isolates of the green alga Chlamydomonas reinhardtii and cultured the pools under multiple environmental conditions. Strains from the outcompeting populations showed substantial (in some cases over 3 fold) increases in productivity over the parental lines under certain environments related to biomass production, including laboratory conditions as well as hyperoxia, fluctuating light, high salinity and high temperature. The results indicate that C. reinhardtii has remarkable, untapped, directed evolution capacity that may be harnessed using breeding and competition approaches. The populations were deep sequenced at multiple time points to identify “Selection- Enriched Genomic Loci” (SEGL) that accumulated in the populations, and thus likely confer increased fitness under the respective environmental conditions. With improved resolution, SEGL mapping can identify allelic combinations used for targeted breeding approaches, generating elite algal lines with multiple desirable traits, as well as to further understand the genetic and mechanistic bases of photosynthetic productivity.

scholarly journals Evaluating Multi-Angle Photochemical Reflectance Index and Solar-Induced Fluorescence for the Estimation of Gross Primary Production in Maize

2020 ◽  
Vol 12 (17) ◽  
pp. 2812
Author(s):  
Jinghua Chen ◽  
Qian Zhang ◽  
Bin Chen ◽  
Yongguang Zhang ◽  
Li Ma ◽  
...  
Keyword(s):  
Primary Production ◽  
Linear Model ◽  
Environmental Conditions ◽  
Gross Primary Production ◽  
Coefficient Of Determination ◽  
Physiological Factors ◽  
Photochemical Reflectance Index ◽  
Spatial And Temporal Scales ◽  
Maize Field ◽  
Use Efficiency

The photochemical reflectance index (PRI) has been suggested as an indicator of light use efficiency (LUE), and for use in the improvement of estimating gross primary production (GPP) in LUE models. Over the last two decades, solar-induced fluorescence (SIF) observations from remote sensing have been used to evaluate the distribution of GPP over a range of spatial and temporal scales. However, both PRI and SIF observations have been decoupled from photosynthesis under a variety of non-physiological factors, i.e., sun-view geometry and environmental variables. These observations are important for estimating GPP but rarely reported in the literature. In our study, multi-angle PRI and SIF observations were obtained during the 2018 growing season in a maize field. We evaluated a PRI-based LUE model for estimating GPP, and compared it with the direct estimation of GPP using concurrent SIF measurements. Our results showed that the observed PRI varied with view angles and that the averaged PRI from the multi-angle observations exhibited better performance than the single-angle observed PRI for estimating LUE. The PRI-based LUE model when compared to SIF, demonstrated a higher ability to capture the diurnal dynamics of GPP (the coefficient of determination (R2) = 0.71) than the seasonal changes (R2 = 0.44), while the seasonal GPP variations were better estimated by SIF (R2 = 0.50). Based on random forest analyses, relative humidity (RH) was the most important driver affecting diurnal GPP estimation using the PRI-based LUE model. The SIF-based linear model was most influenced by photosynthetically active radiation (PAR). The SIF-based linear model did not perform as well as the PRI-based LUE model under most environmental conditions, the exception being clear days (the ratio of direct and diffuse sky radiance > 2). Our study confirms the utility of multi-angle PRI observations in the estimation of GPP in LUE models and suggests that the effects of changing environmental conditions should be taken into account for accurately estimating GPP with PRI and SIF observations.

scholarly journals Big dairy data to unravel effects of environmental, physiological and morphological factors on milk production of mountain-pastured Braunvieh cows

2020 ◽  
Vol 7 (7) ◽  
pp. 200638
Author(s):  
Solange Duruz ◽  
Elia Vajana ◽  
Alexander Burren ◽  
Christine Flury ◽  
Stéphane Joost
Keyword(s):  
Climate Change ◽  
Milk Production ◽  
Environmental Conditions ◽  
Natural Hazard ◽  
Food Shortage ◽  
High Mountain ◽  
Physiological Factors ◽  
Limited Impact ◽  
New Model ◽  
Lactation Cycle

The transhumance system, which consists in moving animals to high mountain pastures during summer, plays a considerable role in preserving both local biodiversity and traditions, as well as protecting against natural hazard. In cows, particularly, milk production is observed to decline as a response to food shortage and climatic stress, leading to atypical lactation curves that are barely described by current lactation models. Here, we relied on 5 million monthly milk records from over 200 000 Braunvieh and Original Braunvieh cows to devise a new model accounting for transhumance, and test the influence of environmental, physiological and morphological factors on cattle productivity. Counter to expectations, environmental conditions in the mountain showed a globally limited impact on milk production during transhumance, with cows in favourable conditions producing only 10% more compared with cows living in detrimental conditions, and with precipitation in spring and altitude revealing to be the most production-affecting variables. Conversely, physiological factors such as lactation number and pregnancy stage presented an important impact over the whole lactation cycle with 20% difference in milk production, and alter the way animals respond to transhumance. Finally, the considered morphological factors (cow height and foot angle) presented a smaller impact during the whole lactation cycle (10% difference in milk production). The present findings help to anticipate the effect of climate change and to identify problematic environmental conditions by comparing their impact with the effect of factors that are known to influence lactation.

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