Recipient Organization
MICHIGAN STATE UNIV
(N/A)
EAST LANSING,MI 48824
Performing Department
Horticulture
Non Technical Summary
Juice grape production in several Viticultural regions is in peril. Rising production costs along with stagnant pricing of thi commodity has led to a decline in profitability. It is unlikely that prices for this commodity will increase dramaticaly in th near future. Therefore, the best option for returning proftability to this commodity is to increase yields per acre while reducing production costs. Increased mechanization of production methods for juice grape is a stratey to achieve recuced costs. A change in the basic vineyard archetectureof a juice grape vineyard to increase the amount of functional vine canopy ( leafarea)is a strategy fot increasing yield per acre. A new vineyard arcchetecture for a juice-grape vineyard must lend itself to mechanization so that the total vineyard program achieves increased profitability for the grower. That is purpose of this project.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Goals / Objectives
(1) To evaluate a new vineyard architecture for juice grape producers which will be capable of being heavily mechanized while increasing yield. (2) To determine a combination of rootstock and vine spacing that will produce an optimum vine size for a new vineyard architecture for a Concord vineyard in Michigan.
Project Methods
Whereas the long term Michigan state average yield is about 4.9 tons/acre, well-managed Michigan Concord vineyards average about 6 tons/acre.(Terry Holloway, personal communication, 2015). Several modifications from the prevailing vineyard architecture of commercial Concord vineyards in Michigan were made to create the experimental vineyard in this project so that the yield per acre of a well-managed Concord vineyard could be increased. These changes are:1. Change 9-foot row spacing to 8-ft row spacing. At an 8-ft row spacing, the vine count changes from 605 to 681 vines/acre or a 12.5% increase. Therefore a base yield of 6 tons/acre might increase by 0.75 tons/acre.2. Change the top-wire cordon training system to a 2-tier training system. When using a vertically-divided training system for wine grapes, such as Scott Henry, the yield increase, if vine size is sufficiently large, is about 25%. A 25% increase of a base yield of 6 tons/acre is 1.5 tons/acre.3. Change to a higher density planting. If a 2-tier training system is utilized, the full capacity of the vine should be capable of being utilized in a smaller vine space. If vine space is reduced from 8 feet to 7 feet, then all other factors being equal, the number of vines increases from 605 to 681 vines/acre or a 12.5% increase. At a base yield of 6 tons/acre, a 12.5% increase equals 0.75 tons/acre.4. Create increased node fruitfulness from shoot positioning. This might increase yield/node by 10%. At a base yield of 6 tons/acre, a 10% increase in yield equals 0.6 tons/acre. Adding these four factors together, there might be a 3.6 tons/acre increase or a total yield of 9.6 tons/acre. A typical commercial Concord vineyard with 9-foot rows and 6-foot high trellis and 24" wide canopy has a potential canopy surface area of 67,760 ft2 / acre. Increasing the trellis height to 7 feet adds 9680 ft2 / acre of potential canopy surface area. Narrowing rows to 8 feet adds 8512 ft2 / acre of potential canopy surface area. When both of these modifications are made, the increase in potential canopy surface area is 19,408 ft2 / acre or a 29% increase over the current standard Concord vineyard architecture. There are two main experiments in this project. Experiment 1 is a factorial design involving vine training systems and rootstocks. Experiment 2 is a factorial design involving rootstocks and vine spacing. Experiment 1 -Two vine training systems are being compared. The first is top-wire cordon (also known as Hudson River Umbrella - HRU). Vines are trained to a bilateral cordon at six feet above the vineyard floor. The second training system is a 2-tier cordon. Vines are trained with bilateral cordons at 7 and 4 feet above the vineyard floor. The second variable is the S04 rootstock. Vines are being grown on either their own roots or on S04 rootstock. This results in four training system/rootstock combinations. Each of these combinations is an experimental unit. Each experimental unit is a row of 50 grapevines. Four rows of vines constitute a block of vines. There are eight blocks in the experiment plus two outside guard rows. This totals 34 rows of vines of 50 vines each or 700 vines. Vines are planted with a row and vine spacing of 8 feet by 8 feet. This results in a vine density of 605 vines per acre. The experiment occupies 2.8 acres. Experiment 2 - One variable in this experiment is rootstock. The five rootstock treatments are: (1) own-rooted, (2) C3309, (3) 420A, (4) Vitis riparia, and (5) 101-14 mgt. Other rootstocks to include hardy rootstocks from the University of Minnesota breeding program may be planted in guard rows. The second variable in this experiment is vine spacing at 7, 8 and 9 feet. There are 15 rootstock/vine spacing combinations. Each of these combinations is an experimental unit. There are six vines per experimental unit. The resulting 15 experimental units are planted in a block. There are eight blocks in the experiment with a 3-vine guard post length between each block and at each end of the row. Each block contains a minimum of 8 vines for each vine spacing/rootstock combination. The 7-foot and 8-foot vine spacings have approximately 10 vines and 9 vines per experimental unit to occupy the additional space. All vines in this experiment are trained to the 2-tier cordon training system as described in Experiment 1 and are on an 8-foot row spacing. There are guard rows in the middle and outside of the plot for a total of 33 rows. The entire plot occupies approximately 400 feet by 264 feet or 2.4 acres. The vines in both experiments will be managed with a mechanization program that includes pruning and shoot positioning devices, which are fabricated specifically for the vineyard architecture described above. Mechanical pruning will be used when vines have attained adequate maturity. Data for both experiments will include pruning weights, yield and fruit quality.