The photosynthetic capacity, nutrient content, and nutrient use efficiency of different needle age-classes of black spruce (Piceamariana) found in interior Alaska

1983 ◽  
Vol 13 (5) ◽  
pp. 834-839 ◽  
Author(s):  
J. L. Hom ◽  
W. C. Oechel

The photosynthetic capacity of different needle age-classes of black spruce (Piceamariana (Mill) B.S.P.) was studied using 14C labelling on whole branches at a site near Fairbanks, Alaska. Black spruce had highest photosynthetic rates in the 1-year-old tissue with the four most current age-classes showing similar high rates before declining with age. Older needles were found to maintain 40% of maximum photosynthetic rates after 13 seasons. Highest level of nitrogen was found in current needles with the first eight age-classes maintaining high levels before declining to 70% of maximum values in the oldest needles. Phosphorus levels were much higher in current tissue with a gradual decline after the 1-year-old tissue to a value of 55% of maximum values in the oldest tissue. Nutrient use efficiency was found to be highest in the 1-year-old tissue and declined with needle age. The loss of nutrient use efficiency may be due to the use of older tissue as aboveground nutrient stores, a decline in the efficiency of the photosynthetic apparatus of the needles, or an increase in the leaf specific weight. Black spruce has adapted to the low nutrient availability with low photosynthetic rates and low nutrient contents. Greater longevity of the needles would maximize the photosynthetic return per unit nitrogen invested in the needles.


1993 ◽  
Vol 23 (11) ◽  
pp. 2435-2442 ◽  
Author(s):  
Alison D. Munson ◽  
Pierre Y. Bernier

The acclimation of planted black spruce (Piceamariana (Mill.) B.S.P.) seedlings to site nutrient condition was assessed by comparing their nutrient status with that of naturally regenerated seedlings on the same site during a 2-year period. The seasonal patterns for N, P, and K status (nutrient concentration and content) were markedly different for planted and natural seedlings. The former showed an early season decline in concentration that was less evident or absent in natural seedlings. This pattern persisted 1 year after planting, although biomass accumulation increased. Nutrient ratios indicated a strong culture regime effect on the balance of nutrients. This effect was considerably diluted 1 year after transplantation. Phosphorus and K levels in 1-year transplants and natural seedlings were close to the defined optimums for black spruce. Nutrient use efficiency of planted seedlings tended to increase with acclimation to site. Retranslocation from older needles of planted seedlings indicated net export of nutrients, while natural seedlings had a storage capacity in older foliage, indicated by net nutrient accumulation at the end of the growing season. Planting significantly reduced biomass allocation to current foliage, and naturally regenerated seedlings produced current foliage earlier in the growing season compared to planted seedlings.





EDIS ◽  
2020 ◽  
Vol 2020 (5) ◽  
Author(s):  
Mary Dixon ◽  
Guodong Liu

Tomato is in high demand because of its taste and health benefits. In Florida, tomato is the number one vegetable crop in terms of both acreage and value. Because of its high value and wide acreage, it is important for tomato production to be efficient in its water and nutrient use, which may be improved through fertigation practices. Therefore, the objective of this new 7-page article is to disseminate research-based methods of tomato production utilizing fertigation to enhance yield and nutrient use efficiency. Written by Mary Dixon and Guodong Liu, and published by the UF/IFAS Horticultural Sciences Department.https://edis.ifas.ufl.edu/hs1392



2018 ◽  
Vol 102 (4) ◽  
pp. 8-10
Author(s):  
Fernando García ◽  
Andrés Grasso ◽  
María González Sanjuan ◽  
Adrián Correndo ◽  
Fernando Salvagiotti

Trends over the past 25 years indicate that Argentina’s growth in its grain crop productivity has largely been supported by the depletion of the extensive fertility of its Pampean soils. Long-term research provides insight into sustainable nutrient management strategies ready for wide-scale adoption.



2021 ◽  
Vol 192 ◽  
pp. 103181
Author(s):  
Jagadish Timsina ◽  
Sudarshan Dutta ◽  
Krishna Prasad Devkota ◽  
Somsubhra Chakraborty ◽  
Ram Krishna Neupane ◽  
...  


Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 959
Author(s):  
Arshad Jalal ◽  
Fernando Shintate Galindo ◽  
Eduardo Henrique Marcandalli Boleta ◽  
Carlos Eduardo da Silva Oliveira ◽  
André Rodrigues dos Reis ◽  
...  

Enrichment of staple food with zinc (Zn) along with solubilizing bacteria is a sustainable and practical approach to overcome Zn malnutrition in human beings by improving plant nutrition, nutrient use efficiency, and productivity. Common bean (Phaseolus vulgaris L.) is one of a staple food of global population and has a prospective role in agronomic Zn biofortification. In this context, we evaluated the effect of diazotrophic bacterial co-inoculations (No inoculation, Rhizobium tropici, R. tropici + Azospirillum brasilense, R. tropici + Bacillus subtilis, R. tropici + Pseudomonas fluorescens, R. tropici + A. brasilense + B. subtilis, and R. tropici + A. brasilense + P. fluorescens) in association with soil Zn application (without and with 8 kg Zn ha−1) on Zn nutrition, growth, yield, and Zn use efficiencies in common bean in the 2019 and 2020 crop seasons. Soil Zn application in combination with R. tropici + B. subtilis improved Zn accumulation in shoot and grains with greater shoot dry matter, grain yield, and estimated Zn intake. Zinc use efficiency, recovery, and utilization were also increased with co-inoculation of R. tropici + B. subtilis, whereas agro-physiological efficiency was increased with triple co-inoculation of R. tropici + A. brasilense + P. fluorescens. Therefore, co-inoculation of R. tropici + B. subtilis in association with Zn application is recommended for biofortification and higher Zn use efficiencies in common bean in the tropical savannah of Brazil.



Plants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 643
Author(s):  
Gaia Santini ◽  
Natascia Biondi ◽  
Liliana Rodolfi ◽  
Mario R. Tredici

Cyanobacteria can be considered a promising source for the development of new biostimulants as they are known to produce a variety of biologically active molecules that can positively affect plant growth, nutrient use efficiency, qualitative traits of the final product, and increase plant tolerance to abiotic stresses. Moreover, the cultivation of cyanobacteria in controlled and confined systems, along with their metabolic plasticity, provides the possibility to improve and standardize composition and effects on plants of derived biostimulant extracts or hydrolysates, which is one of the most critical aspects in the production of commercial biostimulants. Faced with these opportunities, research on biostimulant properties of cyanobacteria has undergone a significant growth in recent years. However, research in this field is still scarce, especially as regards the number of investigated cyanobacterial species. Future research should focus on reducing the costs of cyanobacterial biomass production and plant treatment and on identifying the molecules that mediate the biostimulant effects in order to optimize their content and stability in the final product. Furthermore, the extension of agronomic trials to a wider number of plant species, different application doses, and environmental conditions would allow the development of tailored microbial biostimulants, thus facilitating the diffusion of these products among farmers.



2019 ◽  
Vol 7 (3) ◽  
pp. 368-377 ◽  
Author(s):  
Zilhas Ahmed Jewel ◽  
Jauhar Ali ◽  
Yunlong Pang ◽  
Anumalla Mahender ◽  
Bart Acero ◽  
...  


Sign in / Sign up

Export Citation Format

Share Document