Non-destructive estimation of leaf area in passion fruit (Passiflora edulis L.)

Abstract

The yellow passion fruit is the most commonly cultivated species of the genus Passiflora in commercial plantations in Brazil. Obtaining accurate and easy to perform measurements for determination of leaf area in passion fruit is crucial to understand the interaction between the plant and the environment. The objective of this study was to develop reliable mathematical equations to directly estimate leaf area in passion fruit using linear measurements. Passion fruit leaves may exhibit varying morphology across phenological stages, with lanceolate, bilobed or trilobed leaves. For each morphological pattern, 100 leaves without defects were collected. The real leaf area was measured with a LI-COR 3100 area meter and regression equations were estimated for real leaf area and measurements of length, width, and their corresponding products, using a millimeter ruler. The results showed that determination of leaf area can be easily and accurately performed for passion fruit leaves of varying morphology, using the product of the linear measurements of length and width. The linear equations chosen for determining leaf area through the product of width and length were 0.25 + 0.64x (lanceolate), -4.82 + 0.69x (bilobed) and -0.81 + 0.54x (trilobed).

Evolution of larval gregariousness is associated with host plant specialisation, but not host morphology, in Heliconiini butterflies

“…To determine whether larger leaves predict gregarious larvae, we recorded the mature leaf size of each Passifloraceae in our dataset, given by Ulmar and MacDougal as separate ranges (minimum and maximum) of leaf length and width (both cm). Here, we first calculated the median value of these ranges, then multiplied one median by the other to gain an estimate of the median leaf surface area, assuming an idealised leaf shape, which was used as a final value for what we term ‘leaf size’ (de Luna Souto et al., 2017). We acknowledge that, given the leaf shape diversity in Passilfora , the leaf surface area calculated here is likely a crude estimate of overall leaf tissue available to larvae.…”

Glucosylceramides from Cladosporium and Their Roles in Fungi–Plant Interaction

“…Either fresh or dry (after 48 h at 65 • C) weight of roots was determined. For these evaluations, five individual plants after GlcCer or buffer pulverization, or plants without any treatment, were analyzed, following the non-destructive method described by Souto et al (2017) [21]. Fresh and dry weights were determined using the accurate electronic scale JA3003N, from Bioprecisa Co, Curitiba, PR, Brazil.…”

Developing an Accurate and Fast Non-Destructive Single Leaf Area Model for Loquat (Eriobotrya japonica Lindl) Cultivars

“…So far, several models and regression equations have been proposed, either to be applied at the leaf [11,13] or shoot level [14,15,16,17,18,19,20,21,22,23]. Until now, models and regression equations for fruit trees cover several species, like for instance, apricot [24], avocado [25], banana [26], blackberry [25], cacao [27], chestnut [28], citrus [29], grapevine [14,15,20,25,30,31,32,33], guava [34], hazelnut [18], kiwifruit [25,35], lotus plum [25], mango [36], medlar [37], passion fruit [38], peach [39], persian walnut [40], persimmon [25,41], pistachio [42], rabbiteye blueberry [43], red currant [25], small fruits [44], red raspberry [25], sour orange [45], strawberry [46,47], pecan [48], sweet cherry [49,50], and white mulberry [51]. In this context, it seems interesting to also analyse the loquat ( Eriobotrya japonica Lindl), a fruit tree species belonging to the Rosaceae family.…”