scholarly journals Evaluation of the Agromorphological Determinants of the Spread of the Bacterial Disease in Orchards of the Main Mango-Producing Regions in Côte d'Ivoire

Author(s):  
Brou Kouassi Guy ◽  
Doumbouya Mohamed ◽  
Oro Zokou Franck ◽  
Doga Dabé ◽  
Yapo N'guéssan Patrick ◽  
...  

The use of agroecological practices for the management of phytosanitary problems has become a major issue in the context of sustainable development. It is with this in mind that this study was initiated in the regions of Bagoué, Poro and Tchologo. This study consisted of investigating the determinants likely to promote the spread of the bacterial disease in 720 mango trees of the Kent variety distributed in 20 orchards in the regions of Poro, Tchologo and Bagoué. During this study, the incidence and severity of bacterial disease on leaves and fruits (IsFe, IsFr, IcFe, IcFr) as well as agromorphological parameters such as East-West and North-South spans, total leaf area, fruit load, trunk circumference, total height and number of main branches (En EO and NS, SFT, ChFr, CirTr, HaTr and RamP) were measured. The performance of the pearson correlation test revealed that spans (N-S and E-O), HaTr, SFT and ChFr are the 4 agromorphological determinants that promote the spread of bacteriosis in orchards of the three (3) regions. The synthesis of the results of the ACP and the CAH supplemented by a multivariate analysis (MANOVA) made it possible to structure the mango orchards into three (3) homogeneous groups. Group 1 orchards (VB4, VB8, VS1, VF5, VK1, VB7, VF2 and VK2) expressed the lowest severity indices and the incidence of bacteriosis on the leaves (respectively 15.21 ± 8.87% ; 12.21 ± 6.54%) and fruits (respectively 13.11 ± 4.75%; 10.40 ± 2.93%). These orchards featured mango trees with medium trunk circumferences (99.14 ± 17.24 cm), medium trunk heights (145.29 ± 7.24 cm) and smallest spans (6.85 ± 1, 13 m for the NS span and 6.79 ± 1.18 m for the EO span) and total leaf area (15.61 ± 0.06 cm). These results could help develop an agroecological control strategy for the sustainable management of bacterial disease.

2018 ◽  
Vol 40 (6) ◽  
Author(s):  
Marlúcia Pereira dos Santos ◽  
Victor Martins Maia ◽  
Fernanda Soares Oliveira ◽  
Rodinei Facco Pegoraro ◽  
Silvânio Rodrigues dos Santos ◽  
...  

Abstract The estimation of pineapple total leaf area by simple, fast and non-destructive methods allow inferences related to carbon fixation estimative, biotic and abiotic damages and correlating positively with yield. The objective was to estimate D leaf area and total leaf area and of ‘Pérola’ pineapple plants from biometric measurements. For this purpose, 125 slips were selected and standardized by weight for planting in pots. Nine months after planting in a greenhouse, the plants were harvested to evaluate the total leaf area of the plant, D leaf area and D leaf length and width using a portable leaf area meter. Pearson correlation analysis was made and it was observed significative positive and strong correlation among the studied variables. Then, regression models were adjusted. It was observed that the D leaf area of ‘Pérola’ pineapple can be estimated from the length and width of this same leaf and the total leaf area can be estimated from the D leaf area.


HortScience ◽  
2006 ◽  
Vol 41 (3) ◽  
pp. 607-611
Author(s):  
Olanike O. Onayemi ◽  
Catherine C. Neto ◽  
Justine E. Vanden Heuvel

The effect of partial defoliation (rate and timing) on vine carbohydrate concentration and the development of phenolic compounds in field-grown `Stevens' cranberry fruit was investigated in two experiments. In Expt. 1, partial defoliation rates of 0%, 18%, 39%, and 53% of total leaf area were applied before new growth, at fruit set, at midfruit development, and preharvest. In Expt. 2, treatments of 0% and 34% removal of new leaves were applied at postfruit set, and at midfruit development. In both experiments, upright samples were harvested for carbohydrate analysis 10d after defoliation, and fruit were removed for analysis before commercial harvest of the site. While total berry phenolic concentration was unaffected by partial defoliation in both studies, the separate pools of flavonoid compounds were affected differently by treatment. In Expt. 1, total flavonol concentration at harvest was improved by the highest rate of partial defoliation (53% of total leaf area) at both fruit set and midfruit development. Total anthocyanin concentration was improved by partial defoliation rates of 39% and 53% of total leaf area compared to the 18% defoliation treatment, but was not affected by timing of defoliation. Pearson correlation coefficients indicated that total flavonol concentration was positively correlated with vine total nonstructural carbohydrate concentration at preharvest, while total anthocyanin concentration was negatively correlated with vine soluble carbohydrates, starch, and total nonstructural carbohydrate concentration at midfruit development. In Expt. 2, total phenolics, flavonols, and anthocyanins were unaffected by partial defoliation; however there was a negative correlation between total anthocyanin concentration in the fruit and soluble carbohydrate concentration in the vine at midfruit development. In these experiments, partial defoliation early in the growing season improved total flavonols and total anthocyanins. Production of flavonols and anthocyanins appeared to be regulated independently of each other.


2021 ◽  
Vol 22 (10) ◽  
Author(s):  
Benyamin Lakitan ◽  
Kartika Kartika ◽  
Laily Ilman Widuri ◽  
Erna Siaga ◽  
Lya Nailatul Fadilah

Abstract. Lakitan B, Kartika K, Widuri LI, Siaga E, Fadilah LN. 2021. Lesser-known ethnic leafy vegetables Talinum paniculatum grown at tropical ecosystem: Morphological traits and non-destructive estimation of total leaf area per branch. Biodiversitas 22: 4487-4495. Talinum paniculatum known as Java ginseng is an ethnic vegetable in Indonesia that has also been utilized as a medical plant. Young leaves are the primary economic part of T. paniculatum, which can be eaten fresh or cooked. This study was focused on characterizing morphological traits of T. panicultaum and developing a non-destructive yet accurate and reliable model for predicting total area per leaf cluster on each elongated branch per flush growth cycle. The non-destructive approach allows frequent and timely measurements. In addition, the developed model can be used as guidance for deciding the time to harvest for optimum yield. Results indicated that T. paniculatum flourished rapidly under wet tropical conditions, especially if they were propagated using stem cuttings. The plants produced more than 50 branches and more than 800 leaves, or on average produced more than 15 leaves per branch at the age of nine weeks after planting (WAP). The zero-intercept linear model using a combination of two traits of length x width (LW) as a predictor was accurate and reliable for predicting a single leaf area (R2 = 0.997). Meanwhile, the estimation of total area per leaf cluster was more accurate if three traits, i.e., number of leaves, the longest leaf, and the widest leaf in each cluster were used as predictors with the zero-intercept linear regression model (R2 = 0.984). However, the use of a single trait of length (L) and width (W) of the largest leaf within each cluster as a predictor in the power regression model exhibited moderately accurate prediction at the R2 = 0.883 and 0.724, respectively.


Genetika ◽  
2003 ◽  
Vol 35 (1) ◽  
pp. 1-9 ◽  
Author(s):  
Nada Hladni ◽  
Dragan Skoric ◽  
Marija Kraljevic-Balalic

The main goals of sunflower breeding in Yugoslavia and abroad are increased seed yield and oil content per unit area and increased resistance to diseases, insects and stress conditions via an optimization of plant architecture. In order to determine the mode of inheritance, gene effects and correlations of total leaf number per plant, total leaf area and plant height, six genetically divergent inbred lines of sunflower were subjected to half diallel crosses. Significant differences in mean values of all the traits were found in the F1 and F2 generations. Additive gene effects were more important in the inheritance of total leaf number per plant and plant height, while in the case of total leaf area per plant the nonadditive ones were more important looking at all the combinations in the F1 and F2 generations. The average degree of dominance (Hi/D)1/2 was lower than one for total leaf number per plant and plant height, so the mode of inheritance was partial dominance, while with total leaf area the value was higher than one, indicating super dominance as the mode of inheritance. Significant positive correlation was found: between total leaf area per plant and total leaf number per plant (0.285*) and plant height (0.278*). The results of the study are of importance for further sunflower breeding work.


2018 ◽  
Vol 39 (5) ◽  
pp. 1937 ◽  
Author(s):  
Caroline Farias Barreto ◽  
Leticia Vanni Ferreira ◽  
Savana Irribarem Costa ◽  
Andressa Vighi Schiavon ◽  
Tais Barbosa Becker ◽  
...  

For strawberry cultivation in Brazil, producers are dependent on imported seedlings. An alternative strategy to reduce this dependence is the use of seedlings obtained from nursery plants grown in a protected environment. However, as these seedlings are produced in the summer and planted at the end of this season or the spring of the following year, it is necessary to control growth to reduce the energy costs of the plants. The objective of this study was to evaluate the effect of different concentrations and periods of application of proexadione calcium (ProCa) on growth control of strawberry seedlings. The experiment was carried out in a greenhouse with seedlings of the cultivars ‘Aromas’ and ‘Camarosa’, produced by rooting stolons and kept in polystyrene trays of 72 cells in a substrate of carbonized rice husk. The experimental design was completely randomized, with a 4 × 2 factorial scheme (4 concentrations of ProCa: 0, 100, 200, and 400 mg L-1 × 2 periods of application: at 20 and 30 days after the planting period of rooting stolon). Plant survival, crown diameter, petiole length, total leaf area, specific leaf area, chlorophyll concentration, and dry mass of the crown and shoot were evaluated. The application of ProCa at 20 days after the planting period of the rooting stolon at the concentrations of 200 and 400 mg L-1 favored the reduction of petiole length in plants of ‘Aromas’ strawberry and total leaf aerial in ‘Camarosa’ strawberry. The application of ProCa from the concentration of 100 mg L-1 reduced the vegetative growth of ‘Aromas’ and ‘Camarosa’ strawberry seedlings cultivated in substrate.


2020 ◽  
Vol 12 (2) ◽  
pp. 269 ◽  
Author(s):  
Shunfu Xiao ◽  
Honghong Chai ◽  
Ke Shao ◽  
Mengyuan Shen ◽  
Qing Wang ◽  
...  

Sugar beet is one of the main crops for sugar production in the world. With the increasing demand for sugar, more desirable sugar beet genotypes need to be cultivated through plant breeding programs. Precise plant phenotyping in the field still remains challenge. In this study, structure from motion (SFM) approach was used to reconstruct a three-dimensional (3D) model for sugar beets from 20 genotypes at three growth stages in the field. An automatic data processing pipeline was developed to process point clouds of sugar beet including preprocessing, coordinates correction, filtering and segmentation of point cloud of individual plant. Phenotypic traits were also automatically extracted regarding plant height, maximum canopy area, convex hull volume, total leaf area and individual leaf length. Total leaf area and convex hull volume were adopted to explore the relationship with biomass. The results showed that high correlations between measured and estimated values with R2 > 0.8. Statistical analyses between biomass and extracted traits proved that both convex hull volume and total leaf area can predict biomass well. The proposed pipeline can estimate sugar beet traits precisely in the field and provide a basis for sugar beet breeding.


2003 ◽  
Vol 54 (4) ◽  
pp. 371 ◽  
Author(s):  
T. S. Pritsa ◽  
D. G. Voyiatzis ◽  
C. J. Voyiatzi ◽  
M. S. Sotiriou

The aim of this work was to assess growth traits during the initial developmental stages of olive seedlings, which could be correlated to time to first flowering, facilitating fast selection in olive breeding programs. The experimental material consisted of 232 olive seedlings derived from controlled crosses of 'Kalamon' with self (KA × KA), with 'Amphissis' (KA × AM), and with 'Koroneiki' (KA × KO) and from open pollination of 'Kalamon', 'Amphissis', 'Koroneiki', 'Chalkidikis', and 'Manzanillo'. Vegetative traits of the seedlings, including canopy height and diameter, length of lateral vegetation, number of leaves, mean and total leaf area per plant, leaf shape characteristics, and specific leaf area (SLA), were recorded until 15 months after sowing. The first seedlings to initiate flowers, 4 years after sowing, were also recorded. The existence of correlations between the above growth traits and time to first flowering was investigated. In single-branched seedlings 6 months after sowing, height measured at this stage was significantly correlated with the mean and total leaf area per plant, specific leaf area, and other vegetative traits measured 15 months after sowing. Seedlings with high values of these parameters were the first to initiate flowers 33 months later. Our results indicated that pre-selection of olive seedlings for earliness of first flowering is possible, based on vegetative characteristics assessed very early in their development.


2015 ◽  
Vol 61 (10) ◽  
pp. 735-743 ◽  
Author(s):  
Yusuke Hagiwara ◽  
Shunsuke Matsuoka ◽  
Satoru Hobara ◽  
Akira S. Mori ◽  
Dai Hirose ◽  
...  

Fungal decomposition of lignin leads to the whitening, or bleaching, of leaf litter, especially in temperate and tropical forests, but less is known about such bleaching in forests of cooler regions, such as boreal and subalpine forests. The purposes of the present study were to examine the extent of bleached area on the surface of leaf litter and its variation with environmental conditions in subboreal and subalpine forests in Japan and to examine the microfungi associated with the bleaching of leaf litter by isolating fungi from the bleached portions of the litter. Bleached area accounted for 21.7%–32.7% and 2.0%–10.0% of total leaf area of Quercus crispula and Betula ermanii, respectively, in subboreal forests, and for 6.3% and 18.6% of total leaf area of B. ermanii and Picea jezoensis var. hondoensis, respectively, in a subalpine forest. In subboreal forests, elevation, C/N ratio and pH of the FH layer, and slope aspect were selected as predictor variables for the bleached leaf area. Leaf mass per area and lignin content were consistently lower in the bleached area than in the nonbleached area of the same leaves, indicating that the selective decomposition of acid unhydrolyzable residue (recalcitrant compounds such as lignin, tannins, and cutins) enhanced the mass loss of leaf tissues in the bleached portions. Isolates of a total of 11 fungal species (6 species of Ascomycota and 5 of Basidiomycota) exhibited leaf-litter-bleaching activity under pure culture conditions. Two fungal species (Coccomyces sp. and Mycena sp.) occurred in both subboreal and subalpine forests, which were separated from each other by approximately 1100 km.


2015 ◽  
Vol 08 (02) ◽  
pp. 1550002 ◽  
Author(s):  
Ni Jiang ◽  
Wanneng Yang ◽  
Lingfeng Duan ◽  
Guoxing Chen ◽  
Wei Fang ◽  
...  

Total green leaf area (GLA) is an important trait for agronomic studies. However, existing methods for estimating the GLA of individual rice plants are destructive and labor-intensive. A nondestructive method for estimating the total GLA of individual rice plants based on multi-angle color images is presented. Using projected areas of the plant in images, linear, quadratic, exponential and power regression models for estimating total GLA were evaluated. Tests demonstrated that the side-view projected area had a stronger relationship with the actual total leaf area than the top-projected area. And power models fit better than other models. In addition, the use of multiple side-view images was an efficient method for reducing the estimation error. The inclusion of the top-view projected area as a second predictor provided only a slight improvement of the total leaf area estimation. When the projected areas from multi-angle images were used, the estimated leaf area (ELA) using the power model and the actual leaf area had a high correlation coefficient (R2 > 0.98), and the mean absolute percentage error (MAPE) was about 6%. The method was capable of estimating the total leaf area in a nondestructive, accurate and efficient manner, and it may be used for monitoring rice plant growth.


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