Anatomy, chlorophyll content and photosynthetic potential in grapevine leaves under plastic cover

Abstract

-The present study evaluated the anatomy, chlorophyll content and photosynthetic potential of grapevine leaves grown under plastic cover. The experiment was carried out in vineyards of moscato Giallo cultivar covered and uncovered with plastic. A block design with 10 selected plants was used for each area (covered and uncovered). Twelve leaves (six of them fully exposed to solar radiation and six grown under shaded conditions) were collected from each area and were fixed and analyzed microscopically (thickness of the adaxial and abaxial epidermis and of the palisade and spongy parenchymas). Chlorophyll content and photosynthetic potential were determined in the vineyard at veraison and after harvest. Plastic covering increased the thickness of the palisade parenchyma in exposed and shaded leaves due to solar radiation restriction. however, the leaves from the covered vineyard did not have the same response to the restriction of solar radiation, as observed in the uncovered vineyard. The thickness of the adaxial and abaxial epidermis and of the spongy parenchyma did not vary due to solar radiation restriction. Chlorophyll content increased in the leaves of covered plants. The photosynthetic potential of the vines is not affected by solar radiation restriction imposed by plastic cover due to anatomical modification in leaves. Index terms: Vitis vinifera, adaptation, grapevine, protected crop, microclimate. ANATOMIA, TEOR DE CLOROFILA E POTENCIAL FOTOSSINTÉTICO DE FOLHAS DE VIDEIRAS SOB COBERTURA PLÁSTICARESUMO -o presente trabalho avaliou a anatomia, o teor de clorofila e as respostas fotossintéticas em diferentes níveis de radiação solar em folhas de videiras cultivadas sob cobertura plástica. o experimento foi realizado em vinhedo com a cultivar Moscato Giallo, com e sem cobertura plástica. A avaliação da anatomia foliar foi realizada em 10 plantas, nas áreas coberta e descoberta. No estádio fenológico de mudança de cor das bagas, em cada área, foram coletadas seis folhas expostas à radiação solar e seis sombreadas, as quais foram fixadas e micrografadas (espessuras das epidermes adaxiais e abaxiais e dos parênquimas paliçádicos e lacunosos). O teor de clorofila e o potencial fotossintético foram avaliados na mudança de cor das bagas e após a colheita. A diminuição da radiação solar pela cobertura plástica propicia um incremento da espessura do parênquima paliçádico em folhas expostas e sombreadas. As epidermes adaxiais e abaxiais e o parênquima lacunoso não variam suas espessuras em função da diminuição de radiação solar. O teor de clorofila aumenta nas folhas das plantas cultivadas sob cobertura plástica. o potencial fotossintético das videiras não é afetado pela restrição de radiação solar da cobertura plástica devido à modificação na anatomia das folhas. Termos para indexação: Vitis vinifera, adaptação, cultivo protegido, microclima, videira.Rev. Bras.

Physiological and agronomical responses of Syrah grapevine under protected cultivation

“…The decreased thickness of leaf parenchyma tissues by solar radiation restriction as showed by high SLA values contributed to the highest values of leaf chlorophyll on covered vines. This result was also confirmed by changes in leaf anatomy and increased chlorophyll content of grapevines under protected cultivation to compensate the light restriction by plastic film as showed by Chavarria et al (2012). Higher differences found between diffuse plastic and uncovered may be attributed to the lowest radiation transmission by this plastic material as compared to transparent plastic.…”

“…Increased SLA under plastic cover also confirms that individual leaves were larger but thinner. It is well known in the literature that less structural material per unit area is accumulated in the leaves in response to low-light stress (Chavarria et al, 2012;Poorter et al, 2009;Terashima et al, 2006). The main shoot growth rate and pruning weight also increased under plastic covered probably due, mainly, to the highest minimum air temperature (Table 1) as compared to uncovered treatments (Figures 1a,d).…”

The influence of biodegradable mulches on the yielding of autumn raspberry (Rubus idaeus L.)

“…Raspberry leaves contained significantly higher chlorophyll in the leaves (38.9 SPAD units) in cultivation under covers compared to cultivation without covers (36.8 SPAD units). Similarly, in research by Chavarria et al (2012), grape leaves grown under covers were characterised by a higher content of chlorophyll compared to the leaves of plants grown without covers -the first Table 1 Unauthenticated Download Date | 5/13/18 9:09 AM measurement by 41.1% and the second by 36.17%. In a study by Nair (2012), lettuce grown under covers in plots covered with black mulch had lower chlorophyll content in leaves (27.9 SPAD units) than uncovered plots (29.4 SPAD units).…”

Nutrition, yield and quality of ‘Niagara Rosada’ vine fruits using cattle slurry and plastic cover

“…Mota et al (2009) observed higher (p < 0.05) A, B and total chlorophyll levels among covered 'Cabernet Sauvignon' plants in relation to plants without plastic cover, in only one of four evaluations. However, Chavarria et al (2012) observed higher total chlorophyll levels in 'Moscato Giallo' grapevines kept under plastic cover at two evaluation periods during flowering and after fruit harvest. The results of the present work can be related to the short period between time of cattle slurry application and ICF measurements performed about 2 months after, as well as eventual N losses by nitrate leaching and ammonia volatilization.…”