Lateral Shoot Growth Research Articles

New Host Plant Species of Grapevine Virus A Identified with Vector-Mediated Infections.

Grapevine virus A (GVA) is an economically important virus and a member of the genus Vitivirus (family Betaflexiviridae) that causes a range of symptoms with qualitative and quantitative effects on grape production. Wild and domesticated species of Vitis, including hybrids used as rootstocks, are considered important natural hosts of GVA. Mechanical transmission to some herbaceous plant species, graft transmission, and vector transmission from grape to grape by various mealybugs and soft scale insects have been reported. Under laboratory and greenhouse conditions, this study demonstrates the transmission of GVA from grapes to alternative hosts by the vine mealybug (Planococcus ficus). Results of ELISA, end-point one-step RT-PCR, and real-time RT-PCR, and in some cases electron microscopy and genome sequencing, confirmed successful transmission to three new plant species commonly found in Croatian vineyards: velvetleaf (Abutilon theophrasti), redroot pigweed (Amaranthus retroflexus), and field poppy (Papaver rhoeas), along with Chenopodium murale and the previously known host Nicotiana benthamiana, with variable infection rates. Depending on the host species, symptoms in the form of leaf reddening, yellow spots, reduced growth of lateral shoots, systemic vein clearing, foliar deformation and rugosity, and dwarfism were observed in GVA-infected plants, whereas no symptoms were observed in infected plants of A. theophrasti. Reverse transmission from these new hosts to grapevines by Pl. ficus was not successful. These results confirm four new GVA host species and open new research venues.

The Impact of Auxin and Cytokinin on the Growth and Development of Selected Crops

With a very diverse structure and small molecules, phytohormones are regulators of plant growth and development. Despite the fact that they are synthesized by plants in small quantities, they are highly active physiologically. According to their action, phytohormones can be divided into two categories, as either activators of plant growth and development or as inhibitors, with auxins and cytokinins belonging to the former group. Auxins are synthesized by plants in the apical meristems of shoots, but also in young leaves, seeds, and fruits. They stimulate the elongation growth of shoots and initiate the production of adventitious and lateral roots. Cytokinins, in turn, are formed in root tips and in unripe fruits and seeds. These hormones are responsible for stimulating the growth of lateral shoots, they also stimulate cytokinesis and, consequently, cell division. The aim of this review paper is to present the progress of the research on the effect of selected auxins and cytokinins on crops, considering the prospect of using them in plant growing methods.

The Growth and Yield of Marigold Flowers (Tagetes erecta L.) on Gibberellins Concentration and Pinching Time

Public awareness of beauty and environmental sustainability is getting better. The tropical climate in Indonesia allows many floricultural products to grow well. Considering that the potential is still very large but has not been fully exploited, efforts are needed to encourage floriculture to be more developed. We also need to focus on improving the method of cultivating plants in order to increase their economic value, without destroying the environment. Marigold is one of the most popular multifunctional ornamental plants. The problem in its cultivation is the presence of apical dominance which inhibits the growth of lateral shoots. Vertical growth will encourage flowering lateral shoots. Marigold flowering is affected by the number of flowering branches, so these branches need to be pruned. The aim of this study was to examine the interaction between GA3 concentration and pinching time on the growth and yield of marigold plants. This research was a field experiment with a split plot design consisting of two factors. The first factors as main plot, namely GA3 concentration (15, 200 and 250 ppm) and second factors as sub plot, namely pinching time (14, 21 and 28 days after planting). It was found that the interaction between gibberellins concentration of 200 ppm and pinching time of 14 DAP showed the fastest time of flower appearance. All concentrations of gibberellins gave the same good results for all parameters. Pinching time of 28 DAP gave the best results on plant height 35 DAP and number of flowers.

Jasmonate signaling and remodeling of cell wall metabolism induced by boron deficiency in pea shoots

Boron (B) is an essential element for plant growth but its cellular functions are poorly defined. We conducted transcriptome analysis of shoot apices of pea ( Pisum sativum L.) growing for up to 18 days in the presence or absence of borate. Shoots of B deficient plants exhibited impaired elongation of the apex but increased growth of lateral shoots. Transcriptome analysis at days 10, 14 and 18 revealed 42, 517 and 2684 differentially expressed genes (DEGs), respectively, relating to diverse aspects of cell growth, metabolism, membrane function and cell signaling. Genes involved in jasmonate signaling and cell wall metabolism were upregulated in the B deficient plants. Many DEGs encoded transcription factors (TFs) potentially involved in these responses including many MYB and ethylene-responsive transcription factor (ERF) proteins and two orthologs of MYC2 which has been implicated in jasmonate signaling. Treatment of detached apices with B or jasmonic acid (JA) led to rapid changes in the expression of several of these DEGs. These results are consistent with a major role for borate in cell wall structure, perturbation of which can activate jasmonate signaling and cell wall remodeling. Such changes can help to explain how B deficiency leads to changes in shoot growth and architecture. • Boron deficiency leads to impaired growth of the shoot apex in pea plants. • Boron deficiency activates jasmonate signaling. • Boron deficiency causes widescale changes in expression of genes for cell wall components and metabolism.

SPATIAL VARIABILITY OF ECOPHYSIOLOGICAL AND PRODUCTION COMPONENTS IN IRRIGATED NOBLE GARLIC

Among agricultural components, crop ecophysiological parameters play an essential role in garlic growth and yield. This study aimed to characterize the structure and spatialization of garlic crop parameters, evaluating spatial correlations among yield, lateral shoot growth, and plant ecophysiological components. These consisted of intercellular CO2 concentration, stomatal conductance, transpiration, water-use efficiency, carboxylation efficiency, photosynthetically active radiation, relative humidity around leaves, relative humidity in leaves, air temperature, leaf temperature, vapor pressure deficit, and water content in the air and leaves. Our results showed that irrigated purple garlic yield, lateral shoot growth, and ecophysiological components are spatially dependent. A cross-semivariogram between plant ecophysiological parameters showed negative spatial correlations and spatial dependence, with a coefficient of determination (r2) above 0.730. These findings indicate a close correlation between garlic yield and lateral shoot growth with the ecophysiological parameters studied. In short, purple garlic production had a high inter-spatial correlation with plant transpiration and water contents in the air and leaves.

Efficiency of a biological growth regulator in the cultivation of branched seedlings

The article presents the results of studies on the effectiveness of biological preparations Gibbersib - obtained on the basis of the Fusarium moniliforme strain - a polygibberellin preparation containing a set of gibberellic acids, as well as the preparation 6-Benzyladenine - a synthetic cytokinin intended to activate the vital activity of a plant associated with the growth and development of lateral shoots that improve the crowning of seedlings. According to the results of preparations testing with separate and combined use, the effectiveness of using each of the regulator separately, in comparison with the control, was confirmed. The greatest efficiency was obtained with the use of treatment with combined regulators, which makes it possible to enhance the branching of seedlings.

Planting dates and placement of the Sophora plantation on the irrigated lands of the Tashkent oasis

This article is very relevant to set out organizing plantations in the conditions of the Tashkent oasis. Climatic zones of desert and semi-desert under the influence of new conditions (abundance of light and thermal solar energy, a very long growing season, artificial irrigation), the growth and development of sophora is favorable. Annual seedlings under the influence of mineral fertilizers reach a height of up to 110 cm, the growth of lateral shoots of seedlings in the first year after planting is 33 cm.In the conditions of the Tashkent oasis, sophora favorably tolerates short-term winter low air temperatures (up to 30°C), tolerates soil compaction and has established itself gas-, dust-resistant decorative breed. The number of inflorescences on one tree ranges from 16 to 60 pieces, depending on the layout of the seats. Abundant flowering of sophora was noted with a planting pattern of 5.0x4.0, 5.0x3.0 with sufficient sunlight. The content of rutin in fruit elements ranges from 3.9 to 14.7% and depends on agrotechnical care, the state of the plantings themselves and their location.

Linear growth of lateral shoots of plants belonging to the genus <i>Crataegus</i> L. and the influence of the temperature factor during introduction in the Arctic zone of the Russian Federation (Kola Peninsula)

This study is devoted to assessing the patterns of seasonal growth of lateral shoots of introduced Crataegus L. species beyond the Arctic Circle (using the example of the Kola Peninsula). The paper presents the timing of the onset and end of the linear growth of shoots, the duration of the shoots growth, the influence of the thermal regime on the duration and intensity of the growth of shoots belonging to some species of hawthorn. The beginning of linear growth of shoots in introduced hawthorn species on average occurs on June 1. The sequential series of hawthorn species according to the timing of the onset of linear growth of shoots from early to late is as follows: C. sanguinea, C. flabellata, C. maximowiczii, C. laevigata, C. dahurica, C. russanovii. The average duration of shoot growth for 20182020 was 38 days. The shortest increase was observed in 2019 for C. russanovii, the maximum increase was recorded for C. maximowiczii plants in 2018. The differences in the annual growth of shoots of the studied hawthorn species are due to the intensity, not the duration of growth. C. sanguinea, C. maximowiczii belong to the group of species with the highest requirements for heat accumulated by the end of the shoot growth period, C. dahurica plants were characterized by the least accumulation of positive temperatures.

Micropropagation of the Halophyte Sarcocornia fruticosa (L.) A. J. Scott

Details of investigation to evaluate the effects of the number of nodes (one, two or three) of Sarcocornia fruticosa explants on growth and multiplication rate of plantlets are presented in this paper. The responses of the 3-node explants to some supplementary sources of different aminoacids and growth regulators indol-3-acetic acid, 6-benzylaminopurine and gibberellins A3 were also analysed. Plantlets from 3-node explants showed a marked increase in growth and number of lateral shoots, indicating that Sarcocornia does not respond well when explants are very small. The addition of 100 mg l-1 casein hydrolysate plus 150 mg l-1 glutamine, and 100 mg l-1 casein hydrolysate plus vitamins showed to be good growth promoters in micropropagating Sarcocornia, giving longer plantlets and higher multiplication rates.

НОВЫЙ СОРТ ЯРОВОГО РАПСА ВЕЛЕС

The results of breeding a promising variety of spring rapeseed 'Veles' are presented. The variety was created using chemical mutagenesis. The seeds of the 'Vikros' variety were treated with ethylmethanesul-fonate at a concentration of 0.03%, followed by the selection of lines characterized by early maturity, re-sistance to lodging, and improved biochemical composition of the seeds. The line № 834-16 is distin-guished by the accelerated development, the changed architectonics of the plant. The growth of lateral shoots begins from the base of the main shoot, the lower internodes are shortened, which increases the resistance of plants to lodging. Side shoots of the first order begin to bloom almost simultaneously with the main shoot. Flowering and maturation of seeds on shoots of different orders takes place simultaneous-ly with the central one, which contributes to the friendly maturation and equalization of the obtained seeds. Seeds are characterized by an increased fat content, contain less fiber. The content of crude fat va-ries from 47.4 to 48.8%, crude protein — 19.7–24.4%, crude fiber — 6.52–7.62%. In the composition of fatty acids, the content of valuable oleic acid is 7.15% higher than of standard. The average seed yield for 3 years of testing is 3.28 t/ha, which is 0.64 t/ha higher than the standard. The line was transferred to the State Commission for Variety Testing and Protection of Breeding Achievements under the name 'Veles'. The variety is resistant to lodging. Guarantees the production of 28–32 t/ha of green mass with a yield of up to 6 t/ha of dry matter. The low content of glucosinolates in seeds (11.6–13.9 mmol/g) will allow the use of seeds, cake and meal when feeding animals in high doses. The variety is approved for use from 2021 in 4 regions of the Russian Federation: North-West, Central, Ural and West Siberian.

Does split nitrogen application increase garlic yield and quality?

Nitrogen (N) fertilization is essential for obtaining high garlic yields and satisfying commercial requirements for bulb diameter. However, excess nitrogen may favor the development of lateral shoots. This study aimed to examine the effect of different N application strategies on garlic yield and quality. The experiment was conducted in the field using garlic cv. Chonan and four N fertilization strategies (T1, N fertilizer applied at 15-day intervals; T2, N fertilizer applied before and after clove differentiation; T3, N fertilizer applied before clove differentiation; and T4, N fertilizer applied after clove differentiation). All treatments received the same N rate (210 kg ha-1). A single N application before clove differentiation (T3) favored lateral shoot growth, resulting in the highest incidence of this defect (11.66%). The other treatments did not differ in lateral shoot incidence. Four classes (3–6) of bulb diameter were observed, with treatments ranked in decreasing order as T2 > T1 > T3 > T4. There were no significant differences in garlic yield between single N application treatments (T3 and T4). However, garlic yield differed by 73% between T1 (13,329 kg ha-1) and T4 (7,679 kg ha-1), by 55.31% between T2 (11,927 kg ha-1) and T4, and by 36% between T1 and T3 (9,783 kg ha-1). These results indicate that two N fertilization strategies can be adopted in high-quality garlic production: fortnightly N fertilization or split N application before and after clove differentiation. A single N application is not recommended, regardless of application timing, as it promotes lateral shoot growth and reduces garlic quality and yield.

Spatial Relationships of Soil Physical Attributes with Yield and Lateral Shoot Growth of Garlic

Some compaction states cause changes in soil structure, resulting in increased soil density and soil resistance to penetration (RP). The objective of this study was: a) to analyze the variability of the studied attributes of the plant and the soil; b) define the linear and spatial correlations between plant and soil attributes; and c) to identify the best attributes that correlate spatially with garlic yield (GY) and lateral shoot growth (LSG) for the elaboration of spatial variability maps. The attributes evaluated were GY, apparent soil electrical conductivity (EC), mechanical resistance to penetration (MRP), soil volumetric moisture (SVM), plant water potential (WP), and LSG. The reach values of spatial dependence to be considered in future studies using the same attributes should be between 8 m for apparent soil EC and 23 m for RP. From a spatial point of view, garlic LSG could be estimated by indirect cokriging with soil RP. Values greater than 3000 kPa of soil RP indicated the sites with the lowest GYs.

Age dynamics of growth and development of Populus Pyramidalis in city planting

ABSTRACT Plantations of Populus nigra L. x Populus nigra f. Italica Duroi, growing on the territory of the Ufa industrial hub of the Republic of Bashkortostan Forest-steppe region of the European part of Russia, were selected as an object of study. It is proved that the poplar hybrid is a fast-growing tree. The average growth in height is 0.95 m, in diameter 0.85 mm. The growth of side shoots on average is 50–55 cm during the growing season. The annual linear growth of lateral shoots of the first order of poplar is closely correlated with the sum of the effective temperatures. The hybrid in all urban plantings showed high decorative qualities. With age, the decorativeness of the trees is slightly reduced. The high scores of sanitary, living condition, aesthetic assessment of trees are observed in stands of II, III, IV, V, VI classes of age (up to 30 years). The change in the values of the measured indicators in these age frames is statistically unreliable.

Chemical stress reduces the lateral shoot growth in vernalized garlic

ABSTRACT Brazil’s low garlic productivity is attributed, mainly to the lateral shoot growth, a physiological anomaly characterized by early lateral shoot growth of cloves in noble group garlic cultivars. Considering the aforementioned information, the aim was to evaluate the occurrence of lateral shoot growth and productivity characteristics in garlic plants, cv. Chonan, subject to herbicide chemical stress. In order to do so, an experiment was conducted in outlining randomized blocks in a 3x5 factorial scheme, constituted by three herbicides (paraquat 500 g ha-1; ammonium gluphosinate 400 g ha-1 and glyphosate 720 g ha-1) and five subdoses (0, 5, 10, 15 and 20% of the minimum recommended dose of each herbicide). The electron transport rates (ETR) were evaluated after herbicide application, as well as the culture’s morphological and productive characteristics. The chemical stress caused by herbicides paraquat, ammonium gluphosinate and glyphosate in underdoses of 25, 40 and 36 i.a. ha-1, respectively, was efficient in reducing the electron transport rate and the lateral shoot growth of the Chonan garlic cultivar, and also technically viable in increasing the productivity of commercial bulbs.

Effects of drought at different periods of wheat development on the leaf photosynthetic apparatus and productivity

The problem of drought impact on crop productivity is especially relevant for the leading cereal – wheat, since significant cultivation areas of this crop are located in risky farming zones. The aim of our studies was to compare the peculiarities of drought impact during the period of vegetative growth and reproductive development on the chlorophyll content, activity of chloroplast antioxidant enzymes, the rate of carbon dioxide gas exchange and transpiration as well as productivity of the wheat plants. The studies were carried out on bread winter wheat plants (Triticum aestivum L.) of the Astarta and Natalka varieties grown in a pot experiment. The plants were watered daily to maintain the soil moisture level in the pots in the range 70–60% of field capacity. Drought treatment involving decrease in soil moisture to 30% of the field capacity was applied to some of the plants at late stem elongation stage (BBCH 37-45) and to other plants at heading-anthesis (BBCH 59-65) while control plants were watered as usual. After 7 days of drought, the watering of treated plants was resumed to maintain the soil moisture at the level of control plants until the harvest. The penultimate leaf at the late stem elongation stage and flag leaf at the heading–anthesis period were used for measurements of photosynthetic apparatus response to drought. Plants of both varieties treated at stem elongation stage showed lower decline in the photosynthetic activity, chlorophyll content and grain productivity than those treated at heading-anthesis. The results obtained indicated that photosynthetic apparatus of wheat has a higher drought tolerance at the stem elongation stage than during the heading-anthesis stage. Furthermore, plants stressed at the stem elongation stage revealed better compensatory growth of lateral productive shoots due to superior supply of plants with assimilates after drought termination. Astarta variety had a more drought-tolerant photosynthetic apparatus and higher grain productivity in both well-watered and drought conditions as compared to Natalka variety. The differences between varieties were more contrasting when drought was applied at heading-anthesis.

First Report of Rose Rosette Virus Associated with Rose Rosette Disease Affecting Roses in California

Rose rosette disease (RRD) affecting rose (Rosa spp.) was first described in the western United States and Canada in the early 1940s (Conners 1941) and is now widely distributed in the eastern United States. Typical RRD symptoms include excessive lateral shoot growth and thorniness, witches’ broom, leaf proliferation and malformation, mosaic, red pigmentation, and eventual plant decline and death. RRD is caused by the negative-sense RNA virus, rose rosette virus (RRV), which is vectored by the eriophyid mite (Phyllocoptes fructiphilus Keifer) (Di Bello et al. 2015; Laney et al. 2011). California is one of the main producers of roses in the United States, with a wholesale value of US$17.6 million in 2016 (NASS 2016). In August 2017, symptoms suggestive of RRD were observed in a commercial nursery in Wasco, CA. Leaf tissues were collected from a total of 415 plants, representing many rose cultivars, throughout the entire nursey. Two plants (cvs. Veterans’ Honor and Brilliant Pink Iceberg) showed RRD symptoms, whereas the rest of the samples were asymptomatic. Total RNA was extracted from leaf petioles using the MagMA-96 viral RNA isolation kit (Thermo Fisher Scientific, Waltham, MA) and tested for RRV using a modified quantitative reverse transcription polymerase chain reaction (RT-qPCR) assay developed by Dobhal et al. (2016). Only the two symptomatic plants were positive for RRV. Plants were also microscopically examined, and the P. fructiphilus was observed on several plants throughout the nursery. In June 2018, three garden roses (unknown cultivars) planted in two neighboring homes in Bakersfield, CA, approximately 50 km from the 2017 finds, were identified with RRD symptoms. Leaves from all three plants tested positive for RRV by RT-qPCR and were also infested with P. fructiphilus. To confirm these results, total nucleic acid was extracted from stored (–80°C) leaves from each of the five symptomatic plants and used for cDNA library construction after a ribosomal RNA depletion step (TruSeq Stranded Total RNA with RiboZero Plant kit, Illumina, San Diego, CA). High-throughput sequencing (HTS) was performed on the Illumina NextSeq 500 platform, generating between 15 million and 41 million 75-nucleotide (nt) single-end raw data reads per sample. Analysis of the HTS reads identified nearly complete sequences (>97%) of the seven RRV genome segments from all five samples. The RRV genomes from the two nursery plants sampled in 2017 shared 100% nt identity to one another. The RRV genomes from the three homeowner plants sampled in 2018 shared 100% nt identity to one another but not to the nursery samples (nursery versus homeowner showed 98% nt identity). Sequences from the two locations shared 98% nt identity to the NCBI reference RRV RNA3 (NC_015300) and RNA7 (NC_034981) and 99% nt identity to the NCBI reference RRV RNA1-2 (NC_015298-99) and RNA4-6 (NC_015301, NC_034979, and NC_034980). These results suggest that the samples from these two locations are likely two separate introductions of RRV into California. Two genomic sequences, one from each location, were submitted to GenBank under the accession numbers MH581213 to MH581226. To our knowledge, this is the first report of RRV associated with RRD in California. Further studies will be necessary to assess the relevance and potential threat of this virus to the garden rose nursery industry in California.

FEATURES OF STEM SHOOT DEVELOPMENT AND THE EVALUATION OF AGRONOMIC TRAITS OF HYBRID TOMATO (SOLANUM LYCOPERSICUM L.), CONTAINING GENES OF LIMITED DEVELOPMENT OF LATERAL MERISTEMS IN THE FILM GREENHOURSES

When growing a greenhouse tomato, labor inputs for handling and tying of plants are high. In this regard, it is important to investigate the features of plant growth and create varieties and hybrids for intensive technologies, requiring a minimum of labor inputs for plant care and having a complex of valuable agronomic features. The purpose of the research presented in this article was the selection of tomato hybrid combinations, characterized by high values of productivity signs, low intensity of stem shoot growth and indeterminate type of growth. To achieve the main goal, we studied the growth characteristics of stem shoots and the manifestation of agronomic traits of F1 hybrids Toroza x Line 7, Line 7 x Toroza, Line 7 x Mo 516, C 9464 x Mo 516, C 9464 s Toroza, Line 19/3 x Mo 516, Line 19/3 x Toroza, Line 19/0 x Toroza, Line 19/0 x Mo 516, together with the parent samples. The peculiarities of lateral shoot development and yield signs were investigated in two variants: without breaking-out laterals and with removal of stem shoots on a weekly basis. The dynamics of laterals growth was estimated on plants of the studied samples, which were planted separately, in the course of 30 days after removing previously formed lateral shoots. The hybrids with Line 7 and indeterminate hybrid C 9464 x Mo 516 are characterized by high values of productivity traits. The superiority of indeterminate hybrids was noted in both variants of the experiment on grounds of commercial and total yield. The advantage of the variant "without removing laterals" has been established in yield background. Hybrids F1 Line 19/0 x Mo 516 and Line 19/3 x Thoroza can be recommended as valuable breeding samples, because of high productivity level, low intensity of lateral shoot growth and indeterminate type of growth.

Линейный рост боковых побегов интродуцированных растений рода <i>Crataegus</i> L. в Полярно-Альпийском ботаническом саду-институте

Линейный рост боковых побегов интродуцированных растений рода <i>Crataegus</i> L. в Полярно-Альпийском ботаническом саду-институте

Palissage Reduces Cluster Zone Lateral Shoots Compared to Hedging

Summary Goals: Hedging grapevines is a common canopy management practice in vineyards in the northeastern United States, however it is criticized as being a short-term solution to vine vigor because it can stimulate lateral shoot growth, resulting in a repeated cycle of hedging and leaf removal that costs growers time and money. Palissage is an alternative canopy management tool where long shoot tips are tucked down into the canopy (i.e. Tuck) or wrapped horizontally along the top of the canopy (i.e. Wrap). Anecdotally, growers had reported that palissage initiated earlier cessation of shoot growth during the growing season and reduced or eliminated the need for leaf removal in the fruiting zone due to fewer lateral shoots. This work aimed to test the effects of palissage on vegetative and reproductive growth, yield, disease incidence and severity, and juice and wine sensory on Riesling ( Vitis vinifera L.) grown in northeastern United States. Key Findings Neither palissage treatment affected vine yield in 2015, but Tuck increased yield in 2016 compared to hedging. Wrap reduced the number of laterals in the fruit zone in 2015 but not 2016 compared to hedging. Tuck increased rachis length by 1.4 cm compared to hedging in 2016, but cluster compactness wasn’t reduced by either treatment. Tuck and Wrap decreased botrytis incidence slightly in 2016 when compared to hedging. A sensory panel found that wines grouped separately by treatment based on aroma. Impact and Significance: This study demonstrated that palissage – particularly Wrap - was a potentially viable canopy management technique to reduce lateral growth in the fruit zone. Impacts varied based on year, but in at least one year palissage reduced lateral shoot growth in the fruiting zone, increased rachis length, and maintained or increased yield, although fruit in the Tuck treatment was less ripe. The potential long-term impacts palissage has on vine vigor, yield, and fruit quality need to be further explored, but these methods hold promise to break the hedging-leaf removal cycle in vigorous vineyards.

Annual Under-Vine Cover Crops Mitigate Vine Vigor in a Mature and Vigorous Cabernet franc Vineyard

Excessive vine vegetative growth in wet, cool climates increases management costs and compromises grape quality. The standard practice of bare soil under vines exacerbates the vigor problem. This study examined the ability of under-vine cover crops to mitigate excessive vigor in a mature vineyard. A three-year study was conducted in a mature Cabernet franc vineyard in Ovid, NY. Under-vine cover crops of chicory (CHI), tall fescue (FES), tillage radish (TR), alfalfa (ALF), or natural vegetation (NV) were established annually since 2014 to compare with a control of glyphosate-maintained bare soil (GLY). Pruning weight was reduced 64% by CHI and 54% by FES or TR compared to GLY in 2015. Primary and lateral shoot growth was suppressed by CHI in 2016. Fruiting zone leaf layer number was reduced by all of the under-vine cover crops in 2015, and by CHI and FES in 2016. Yield per vine was not reduced by any of the under-vine cover crops in any year of the study. Under-vine cover crops had little impact on harvest parameters including soluble solids, titratable acidity, pH, or yeast assimilable nitrogen. Soil properties such as aggregate stability, microbial respiration rate, and carbon mineralizability were improved by some cover crops. Although NV, FES, and TR showed little, and ALF showed neutral, effect on vine growth or yield components, CHI effectively alleviated mature vine vigor without reducing yield in a cool climate. Since water or nutrient competition alone did not fully explain the mitigating effect of under-vine cover crops on vine vigor, other mechanisms such as microbial or allelopathic effects of under-vine cover crops should be examined.