Source: CORNELL UNIVERSITY submitted to
NUTRITION PHYSIOLOGY AND MANAGEMENT OF FRUIT CROPS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
TERMINATED
Funding Source
Reporting Frequency
Annual
Accession No.
0186401
Grant No.
(N/A)
Project No.
NYC-145431
Proposal No.
(N/A)
Multistate No.
(N/A)
Program Code
(N/A)
Project Start Date
Oct 1, 2000
Project End Date
Sep 30, 2005
Grant Year
(N/A)
Project Director
Cheng, L.
Recipient Organization
CORNELL UNIVERSITY
(N/A)
ITHACA,NY 14853
Performing Department
HORTICULTURE
Non Technical Summary
(N/A)
Animal Health Component
70%
Research Effort Categories
Basic
30%
Applied
70%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2031110101040%
2031139101020%
2031110102020%
2031139102020%
Goals / Objectives
The overall objective is to develop a better understanding of nutrition physiology of fruit crops of importance to New York (particularly apples and grapes), and design/modify nutrient management practices to improve productivity and fruit quality. Here "nutrition" refers to the process in which nutrients are taken up by plants, assimilated to usable forms, and translocated to the target organ/tissue to perform their function. The term is also used in a broader sense, not only including mineral nutrition, but also carbon nutrition. The specific objectives for the first 5 years are: 1. To determine the dependence of vegetative growth and fruiting on nutrient reserves, particularly nitrogen and carbon reserves, and to identify nutrition factors or processes that limit productivity in New York orchards, and design cultural practices to overcome the limitation to the climate-allowable maximum. 2. To quantify seasonal patterns of nitrogen supply-demand relationship, N partitioning, utilization efficiency, and recycling in response to timing (spring, summer, fall) and method of application (soil vs. foliar) to find the most suitable N management practice under New York soil and climate conditions. 3. To utilize molecular approaches to gain a better understanding of carbon-nitrogen interaction in apple.
Project Methods
1. Determine the dependence of vegetative growth and fruiting on reserve nitrogen and carbohydrates. Nitrogen and carbohydrate reserve levels will be manipulated by 1) manual defoliation in combination with foliar urea application in the fall and 2) carbon dioxide enrichment in combination with foliar or soil application of 15N-labeled fertilizers. 2. Determine nitrogen supply-demand relationship, uptake and partitioning, internal N cycling, and N use efficiency under Northeast climate and soil conditions. Isotopically-labeled 15N fertilizers and sequential destructive harvesting of whole plant will be employed to determine supply-demand relationships, contribution of internal cycling to the overall nitrogen economy, uptake and partitioning, and N use efficiency of field-grown apple and grapevine. 3. Determine carbon-nitrogen interaction via Rubisco in apple Antisense suppression of Rubisco expression will be employed to decrease Rubisco activity in apple plants, and these transgenic plants will be used to study carbon-nitrogen interaction via Rubisco.

Progress 10/01/00 to 09/30/05

Outputs
The overall objective is to develop a better understanding of nutrition physiology of fruit crops of importance to New York, and optimize nutrient management practices to improve productivity and fruit quality. Over the last 5 years, we have determined 1) growth and fruiting of both apple trees and grapevines in relation to reserve nitrogen and reserve carbohydrates; and 2) carbon assimilation and photoprotection in leaves of grapevines in response to nitrogen deficiency We found that foliar nitrogen application in the fall decreased carbohydrate reserves while increasing nitrogen reserves in both young apple trees and grapevines over a wide range of soil N supply. We showed that young apple trees and grapevines with higher N reserves but lower carbohydrate reserves produced a larger total leaf area and higher yield than those with lower N reserves but higher carbohydrate reserves regardless of whether nitrogen was provided or not during the current growing season. These findings provided strong evidence that the growth and development of both young apple trees and grapevines in the spring are mainly determined by reserve nitrogen, not by reserve carbohydrates. We confirmed that both vegetative growth and fruiting of apple trees early in the season are determined by reserve nitrogen not by reserve carbohydrates with bearing trees grown in large pots or in the field by using carbon dioxide enrichment or manual defoliation in combination with nitrogen application after harvesting the crop. We found that under low N supply, most N was stored in proteins with only a small fraction in free amino acids and high concentrations of non-structural carbohydrates accumulated in both apple trees and grapevines. As N supply increased, the proportion of nitrogen in the form of free amino acids increased to make N storage more effective in terms of carbon cost, but proteins remained as the main form of N storage. Conversion of a portion of non-structural carbohydrates to free amino acids and proteins in response to foliar N application increased N reserves while decreasing carbon storage in non-structural carbohydrates, leading to better growth performance of young apple trees and grapevines the following season. Compared with high N leaves, low N leaves had lower carbon assimilation capacity and operating quantum efficiency of PSII, lower activities of the key enzymes in photosynthesis and higher starch concentration. Carbon export during the night was significantly lower under nitrogen limitation. Both the xanthophyll cycle pool size on a chlorophyll basis and the conversion of violaxanthin to antheraxanthin and zeaxanthin at noon increased with decreasing leaf N. In addition, the antioxidant system was up-regulated in response to N limitation. These results showed that the reduced photosynthetic capacity in low N leaves was caused by the coordinated decreases in the activities of key enzymes involved in photosynthesis as a result of direct N limitation and that both xanthophyll cycle-dependent thermal energy dissipation and the antioxidant system were up-regulated to protect low N leaves from photo-oxidative damage under high light.

Impacts
We have made significant progress over the last five years in understanding growth and fruiting of apple trees and grapevines in relation to nitrogen and carbohydrate reserves and optimizing nitrogen management to improve yield and fruit quality of apples and grapes. We found that (1) growth and fruiting of both apple trees and grapevines in the spring are mainly determined by reserve nitrogen, not by reserve carbohydrates; (2) Foliar nitrogen application in the fall improves growth and fruiting of both apple trees and grapevines via converting some non-structural carbohydrates to proteins and free amino acids. These findings lead to the development of a nitrogen management program that emphasizes reserve nitrogen levels for tree fruit nurseries, which allows for early defoliation without compromising tree performance. For cropping apple trees and grapevines with a low N status, nitrogen application after harvest has been recommended to increase reserve nitrogen level and improve growth and fruiting the following year. Many growers are adopting these new practices to improve orchard/vineyard productivity. In addition, we gained a better understanding of the mechanisms regulating carbon assimilation and photoprotection of leaves in response to nitrogen limitation.

Publications

  • Chen, L.S. and L. Cheng. 2004. Photosynthetic enzymes and carbohydrate metabolism of apple leaves in response to nitrogen limitation. Journal of Horticultural Science and Biotechnology 79: 923-929.
  • Chen, L. S. and L. Cheng. 2003. Carbon assimilation and carbohydrate metabolism of Concord grape (Vitis labrusca L.) leaves in response to nitrogen supply. Journal of American Society for Horticultural Science 128: 754-760.
  • Chen, L. S. and L. Cheng. 2003. Both xanthophyll cycle-dependent thermal dissipation and the antioxidant system are up-regulated in grape (Vitis labrusca L.) leaves in response to N limitation. Journal of Experimental Botany 54: 2165-2175.
  • Cheng, L. and L. H. Fuchigami 2002. Growth of young apple trees in relation to reserve nitrogen and carbohydrates. Tree Physiology 22: 1297-1303.
  • Cheng, L., S. Dong, and L. H. Fuchigami 2002. Urea uptake and nitrogen mobilization by apple leaves in relation to tree nitrogen status in autumn. Journal of Horticultural Science and Biotechnology 77: 13-18.
  • Cheng, L. and R. Raba. 2002. Effects of elevated CO2 and nitrogen supply in the fall on reserve carbohydrates and nitrogen and growth performance of young apple trees. 26th International Hort Congress. P152.
  • Cheng, L. and Fuchigami, L. H. 2001. Effects of manual defoliation and foliar urea on reserve nitrogen and carbon status, growth, and yield of apple trees. Hortscience 36: 464.


Progress 01/01/04 to 12/31/04

Outputs
The overall objective is to develop a better understanding of nutrition physiology of fruit crops of importance to New York, and optimize nutrient management practices to improve productivity and fruit quality. The specific objectives during 2004 were to determine growth and fruiting of Concord vines in relation to nitrogen and carbohydrate reserves. Potted Concord vines were fertigated with 0, 5, 10, 15, or 20 mM N in a modified Hoagland solution for 8 weeks during summer. Half of the vines fertigated at each N concentration were sprayed with 3 percent foliar urea twice in late September while the rest served as controls. Four vines from each treatment combination were destructively sampled during dormancy to determine the levels and forms of N and carbohydrates. Nitrogen fertigation during the summer did not significantly alter vine N concentration whereas foliar urea application in the fall significantly increased vine N concentration. Concentrations of total non-structural carbohydrates (TNC) decreased slightly in response to N supply from fertigation. Foliar urea application in the fall significantly decreased TNC concentration at each N fertigation level. Approximately 60 percent of the carbon decrease in TNC caused by foliar urea application was recovered in proteins and free amino acids. Total amount of N in dormant vines increased with increasing N fertigation concentration. Total amount of TNC increased with increasing N fertigation concentration from 0 to 10mM, and then leveled off with further rises in N supply. Foliar urea application increased total N but decreased TNC of dormant vines at each given N fertigation level. In response to foliar urea application, part of the carbon from TNC was incorporated into proteins and free amino acids, leading to a decrease in the carbon stored in TNC and an increase in the carbon stored in proteins and free amino acids. We subsequently determined growth and fruiting of these vines during the second year. The vines were supplied with either no N or sufficient N (10 mM N) from two weeks before bloom to one month after bloom. All the vines were destructively harvested at one month after bloom. When no nitrogen was provided during the regrowth period, vine total leaf area, fruit yield, and total dry weight increased with increasing N supply from fertigation the previous year. Vines sprayed with foliar urea the previous fall produced a larger total leaf area, a higher yield, and a higher total vine dry weight at each given N fertigation concentration. Providing vines with sufficient N during the regrowth period significantly increased total leaf area, fruit yield, and vine total dry weight across the previous N fertigation concentrations, but vines sprayed with foliar urea still had a larger leaf area, a higher yield and a higher total vine dry weight at each given N fertigation concentration. Therefore, we conclude that both vegetative growth and fruiting of young Concord vines are largely determined by reserve nitrogen, not by reserve carbohydrates, and that current season N supply plays a very important role in sustaining vine growth and development, especially fruit growth.

Impacts
These findings provided strong evidence that growth and fruiting of young grapevines in the spring is mainly determined by reserve nitrogen, not by reserve carbohydrates, which contrasts with the conventional view that vine growth and development in the spring is largely limited reserve carbohydrates. This will have significant impact on reserve nutrient management to improve yield and quality of grapevines.

Publications

  • Cheng, L., G. Xia and T. Bates. 2004. Growth and fruiting of young Concord grapevines in relation to reserve nitrogen and carbohydrates. Journal of American Society for Horticultural Science 129: 660-666.
  • Xia, G. and L. Cheng. 2004. Foliar urea application in the fall affects both nitrogen and carbon storage in young Concord grapevines grown under a wide range of nitrogen supply. Journal of American Society for Horticultural Science 129: 653-659.


Progress 01/01/03 to 12/31/03

Outputs
The overall objective is to develop a better understanding of nutrition physiology of fruit crops of importance to New York, and design/modify nutrient management practices to improve productivity and fruit quality. The specific objectives during 2003 were to determine carbon assimilation and metabolism and photoprotection in leaves of Concord grapevines in response to nitrogen deficiency Concord vines were supplied twice weekly for 5 weeks with 0, 5, 10, 15, or 20 mM N in a modified Hoagland solution to generate a wide range of leaf N status. Light-saturated photosynthesis increased curvilinearly as leaf N increased. On a leaf area basis, activities of 6 key enzymes in the Calvin cycle and end-product synthesis increased linearly with increasing leaf N. When expressed on a leaf N basis, activities of the Calvin cycle enzymes increased with increasing leaf N, whereas activities of the 3 key enzymes in sucrose and starch synthesis did not show significant change. Concentrations of glucose, fructose, and sucrose at dusk increased linearly with increasing leaf N, and there was no difference between predawn and dusk measurements. As leaf N increased, starch concentration increased linearly at dusk, but decreased linearly at predawn. The calculated carbon export from starch degradation during the night increased with increasing leaf N. These results showed that the elevated starch level in low N leaves at predawn was the result of the reduced carbon export from starch degradation during the night; and that the reduced photosynthetic capacity in low N leaves was caused by the coordinated decreases in the activities of key enzymes involved in photosynthesis as a result of direct N limitation, not by the indirect feedback repression of photosynthesis via sugar accumulation. We also determined the photoprotective mechanisms in grape leaves in response to N supply. Compared with high N leaves, low N leaves had lower quantum efficiency of PSII as a result of both an increase in non-photochemical quenching and an increase in closure of PSII reaction centers at midday under high photon flux density. Both the xanthophyll cycle pool size on a chlorophyll basis and the conversion of violaxanthin to antheraxanthin and zeaxanthin at noon increased with decreasing leaf N. As leaf N increased, superoxide dismutase activity on a chlorophyll basis decreased linearly; activities of catalase and glutathione reductase on a chlorophyll basis increased linearly; activities of ascorbate peroxidase, monodehydroascorbate reductase and dehydroascorbate reductase expressed on the basis of chlorophyll decreased rapidly first, then gradually reached a low level. In response to N limitation, the contents of reduced ascorbate, dehydroascorbate, reduced glutathione, and oxidized glutathione increased when expressed on a chlorophyll basis, whereas the reduction state of both the ascorbate pool and glutathione pool decreased. It is concluded that both xanthophyll cycle-dependent thermal energy dissipation and the antioxidant system are up-regulated to protect low N leaves from photo-oxidative damage under high light.

Impacts
These findings help us better understand the biochemical mechanisms by which grapevines cope with nitrogen deficiency.

Publications

  • Chen, L. S. and L. Cheng. 2003. Carbon assimilation and carbohydrate metabolism of Concord grape leaves in response to nitrogen supply. Journal of American Society for Horticultural Science 128: 754-760.
  • Chen, L. S. and L. Cheng. 2003. Both xanthophyll cycle-dependent thermal dissipation and the antioxidant system are up-regulated in grape leaves in response to N limitation. Journal of Experimental Botany 54: 2165-2175.


Progress 01/01/02 to 12/31/02

Outputs
The overall objective is to develop a better understanding of nutrition physiology of fruit crops of importance to New York, and design/modify nutrient management practices to improve productivity and fruit quality. The specific objectives during 2002 were to determine growth and fruiting of apple trees in relation to reserve nitrogen and carbohydrates. Gala/M26 trees received one of the following four treatment combinations for 5 weeks after harvest: ambient (360 ppm) without N application, ambient CO2 with 10 mM N application, elevated CO2 (1000 ppm) without N application, or elevated CO2 with 10 mM N application. Before budbreak the following year, one set of trees from each of the 4 treatment combinations was destructively sampled to measure reserve nitrogen and carbohydrates. The remaining trees were divided into two groups. One group did not receive any nitrogen supply while the other group received 10 mM N supply starting from petal fall until Mid-August. Fall CO2 enrichment slightly increased both carbohydrate concentrations and total dry matter of the tree, resulting in a significant increase in the total amount of reserve carbohydrates. N application in the fall significantly increased N content and total amount of N accumulated in the tree, but reduced carbohydrate concentrations. Although fall CO2 enrichment increased total amount of reserve carbohydrates, it did not affect total leaf area, fruit number, fruit yield the following year. Regardless of current nitrogen supply the following season, trees with high N reserves but low carbohydrate reserves had a larger total leaf area, higher fruit number and total yield than those with low N reserves but high carbohydrate reserves. Therefore, the growth and fruiting of apple trees in spring are primarily determined by reserve nitrogen, not by reserve carbohydrates. Spring N supply also significantly increased total leaf area, leaf N content, fruit number, and total yield. The effect of cropload on tree growth and reserve nitrogen and carbohydrates were evaluated using third leaf Honeycrisp/M.9, Jonagold/M.9 and Gala/M.26 trees. Cropload was adjusted at 10-mm king fruit by hand thinning to 0, 3, 6, 9, 12, and 15 fruit/cm2TCA. At harvest fruit number and total fresh weight were recorded. Before budbreak the following spring, spurs, extension growth, and roots were sampled for reserve nitrogen and carbohydrate analysis. Over a wide range of cropload (0 to 14 fruit per cm2 TCA), spur reserve N content and carbohydrate concentration did not change significantly. However, tree vegetative growth, as measured by increase of TCA, decreased as cropload increased. This indicates that apple trees are able to maintain their reserve nitrogen and carbohydrate concentration in response to increasing cropload by reducing vegetative growth. However, this will inevitably result in a decrease the total amount of reserves, which may in turn negatively affect the growth and fruiting the following season.

Impacts
The findings of the project have the potential to improve tree reserve nitrogen status in growing regions with a short leaf retention period, and consequently improve apple productivity and quality.

Publications

  • Cheng, L. and L. H. Fuchigami 2002. Growth of young apple trees in relation to reserve nitrogen and carbohydrates. Tree Physiology 22: 1297-1303.
  • Cheng, L., S. Dong, and L. H. Fuchigami 2002. Urea uptake and nitrogen mobilization by apple leaves in relation to tree nitrogen status in autumn. Journal of Horticultural Science and Biotechnology 77: 13-18.
  • Cheng, L. and R. Raba. 2002. Effects of elevated CO2 and nitrogen supply in the fall on reserve carbohydrates and nitrogen and growth performance of young apple trees. 26th International Hort Congress. P152.


Progress 01/01/01 to 12/31/01

Outputs
The overall objective is to develop a better understanding of nutrition physiology of fruit crops of importance to New York, and design/modify nutrient management practices to improve productivity and fruit quality. The specific objectives during 2001 are (1) to determine growth and fruiting of field-grown apple trees in relation to reserve nitrogen and carbohydrates; and (2) to compare fall foliar urea application with traditional spring soil N fertilization to determine the best nitrogen management regime for optimizing apple yield and quality under NY soil and climate conditions. Six-year-old Marshall McIntosh/M.9 trees were subjected to one of the following four treatments after harvesting: (1) manual defoliation, (2) foliar urea spray, (3) foliar urea followed by manual defoliation, and (4) natural defoliation without foliar urea (control). Manual defoliation alone decreased both reserve carbohydrates and nitrogen in spurs and shoots. As a result, spur leaf development, leaf N content, and fruit number and yield per tree were reduced. Foliar urea application alone increased reserve nitrogen, but decreased reserve carbohydrates. Fruit number and yield per tree tended to be higher in foliar urea treatment than in controls. Trees sprayed with foliar urea followed by manual defoliation tended to have higher reserve nitrogen content, better spur leaf development, and higher fruit number and yield per tree than those manually defoliated. When regression analysis was used to examine fruit number and yield in relation to reserve nitrogen and carbohydrates, it was found that fruit number and yield were significantly related to reserve nitrogen content in spurs and shoots, but not reserve carbohydrates. These results suggest that growth and fruiting of apple trees are more related to reserve nitrogen than reserve carbohydrates. Mature Marshall McIntosh/M.9 trees received one of the following four N treatments at the same rate of 46 lbs/acre: (1) soil applied N in the spring (control), (2) foliar urea sprayed twice at weekly intervals after harvesting, (3) 50/50 split between fall foliar and spring soil application, and (4) 36/64 split between spring foliar and soil application. Fall foliar urea application to Marshall McIntosh increased reserve nitrogen levels in spurs and shoots. However, leaf nitrogen contents in spur leaves and shoot leaves were lower in fall foliar N treatment than in the control and the split application treatments. Trees in the fall foliar N treatment had slightly smaller fruit size, but there was no significant difference in fruit number and yield among the four treatments. Spring foliar and soil split application tended to give the highest leaf N status, fruit size and yield. Fruit quality was not significantly affected by any N treatment. There was no difference in cold hardiness in Marshall McIntosh trees among the four treatments. These results indicate that fall foliar urea spray did not affect tree cold hardiness, but its effect on spur characteristics, leaf N content, fruit size, and yield may be dependent on tree background N status and/or natural N supply capacity of the soil.

Impacts
The findings of the project have the potential to improve tree reserve nitrogen status in growing regions with a short leaf retention period, and consequently improve apple yield and quality.

Publications

  • Cheng, L. and Fuchigami, L. H. 2001. Effects of manual defoliation and foliar urea on reserve nitrogen and carbon status, growth, and yield of apple trees. Hortscience 36: 464.