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1.
Anthracnose caused by the fungus Apiognomonia veneta (Sacc. et Speg.) Höhnel., is the most important and frequent disease affecting mature ornamental plane trees (Platanus×hybrida Brot.=P.×acerifolia (Ait.)Willd.) of central Spain. Symptoms of the disease are: leaf vein and petiole necrosis, bud death, defoliation, proliferation of shoots growing in whorls, short internodes, cankers, necrotic lesions and twigs and branches growing in angles. Based on our previous experience, a disease severity rating scale (DSRS) has been established, consisting of six levels: 0=healthy, 1=initial, 2=low, 3=medium, 4=high and 5=dead. In order to achieve a better and more efficient measure of disease intensity we tried to quantify this visual scale using mathematical criteria. In 2000, 610 mature trees up to 200 years old, divided into 4 age classes, were selected and systematically evaluated using a visual estimation based method. The trees were located in central Spain, mainly in two periurban areas of the town of Aranjuez (south of Madrid) and in three urban areas of Madrid city. Trees were observed in late spring, summer and winter. We recorded visual estimation of disease severity, foliage cover, healthy new shoots, dead branches, shoot growth in whorls and branch growth in angles. The statistical relationship between the parameters, disease severity and all the variables recorded (defoliation, healthy new shoots, etc.) has been evaluated. “Leaf density”, “dead branches” and “healthy shoots” were the variables that help to discriminate better between the different levels of the DSRS. A clearer definition of the different phases of disease severity will facilitate the application of possible control methods and the prediction of the behaviour of other Platanus spp.  相似文献   

2.
Photoperiod is commonly controlled in the commercial production of ornamental crops to induce or prevent flowering. Flower induction in short-day (SD) plants can be prevented or delayed when the natural daylength is short by providing low-intensity lighting during the dark period. A stationary high-pressure sodium (HPS) lamp with an oscillating aluminum parabolic reflector (cyclic HPS) has been developed to provide intermittent lighting to greenhouse crops. We determined the efficacy of a cyclic HPS lamp at preventing flowering in SD plants garden chrysanthemum [Chrysanthemum × grandiflorum (Ramat.) Kitam.] ‘Bianca’, pot chrysanthemum ‘Auburn’, and velvet sage (Salvia leucantha L.) relative to traditional night interruption (NI) lighting strategies. Plants were grown in a glass-glazed greenhouse at a mean daily temperature of 19.5–20.7 °C with natural SD photoperiods. NI lighting was delivered during the middle of the night (2230–0230 h) from a 600 W cyclic HPS lamp mounted at one gable end of the greenhouse or from incandescent (INC) lamps that were illuminated for the entire 4 h (CONT INC) or for 6 min every 30 min for 4 h. Plants under cyclic HPS were grown at lateral distances of 1, 4, 7, 10, or 13 m from under the lamp. Control plants were grown under an uninterrupted 15 h skotoperiod. As the distance from the cyclic HPS lamp increased from 1 to 13 m, the maximum irradiance measured during the NI decreased from 25.4 to 0.3 μmol m−2 s−1 and time to visible inflorescence (VI) and the number of nodes at VI decreased. All species had a VI within 54 d, but ≤10% of plants flowered when grown at a lateral distance of 1 or 4 m from the cyclic HPS lamp or under CONT INC. Plants grown without NI had a VI 2 to 15 d earlier and flowered 7 to 24 d earlier than plants grown at 10 or 13 m from the cyclic HPS. All garden chrysanthemums flowered under cyclic INC, whereas velvet sage and pot chrysanthemum had 15% and 35% flowering, respectively. These results indicate that a cyclic HPS lamp can be used effectively to delay flower induction and prevent flowering in these species when NI is delivered at ≥2.4 μmol m−2 s−1.  相似文献   

3.
The effect of rootstock (‘MaxMa 14’, ‘Weiroot 13’, ‘PiKu 1’, ‘Weiroot 158’, ‘Gisela 5’ and ‘F12/1’) on phenolic acid and flavonol content of “Lapins” sweet cherry was investigated. Phenolic acids and flavonols were isolated from sweet cherries and analyzed by using reversed phase high-performance liquid chromatography (RP-HPLC). The major phenolic acids in sweet cherries were neochlorogenic acid (18–50 mg kg−1), chlorogenic acid (19–62 mg kg−1) and p-coumaric acid derivatives (15–125 mg kg−1). The amount of flavonol quercetin-3-rutinoside (8–37 mg kg−1) was significant as well. There are significant variations in the phenolic compound content among sweet cherry fruits grown on trees grafted on different vegetative rootstocks. The significantly higher chlorogenic acid, neochlorogenic acid, p-coumaric derivative and quercetin-3-rutinoside contents were found in sweet cherry fruits grown on trees grafted on ‘Weiroot 13’ and ‘PiKu 1’ rootstocks. Sweet cherries produced on trees grafted on other rootstocks had significantly lower phenolic compound content.  相似文献   

4.
An efficient procedure is outlined for rapid and mass in vitro propagation of an orchid, Dendrobium draconis Rchb. f. through in vitro culture of thin cross-sections (TCSs) derived from young stems. The TCS explants were excised along the stem from the base to shoot tip of 6-month-old plantlets and cultured on Murashige and Skoog (MS) medium supplemented with 20 g/l sucrose and different concentrations of N6-benzyladenine (BA), kinetin (Kn) and 1-naphthaleneacetic acid (NAA), either individually or in combination. Protocorm-like bodies (PLBs) were directly induced from the TCS explants and completely developed into shoots within 6–7 weeks. The optimal growth regulators combination for maximal PLB development was 2 mg/l BA and 1.0 mg/l NAA, giving rise to 68% of responding explants with an average 11 PLBs per explant. Shoot development was best achieved on MS medium containing sucrose and coconut water. Plantlets, 6–8 cm height were transplanted into coconut husk peat with 92% survival rate in a nursery.  相似文献   

5.
The establishment of in vitro cultures of Echinacea angustifolia D.C. was obtained directly from sections of flower stalks of adult plants. The shoot formation was obtained from this plant material placed on a modified MS basal medium named CH supplemented with 0.5 mg L−1 6-benzylaminopurine (BA). The in vitro propagation procedure of E. angustifolia consisted of three distinct phases: an initial regeneration phase from stalk sections (IP shoots on basal medium with 0.25 mg L−1 BA), an elongation phase on active charcoal and an axillary proliferation of the shoots (AP shoots on basal medium with 0.5 mg L−1 BA).Regenerating calli were established from leaves of in vitro shoots cultured on CH medium supplemented with 3 mg L−1 BA and 0.5 mg L−1 indole-3-butyric acid (IBA). Developed shoots from the callus cultures were subcultured on the CH medium with 0.5 mg L−1 BA (leaf regenerated shoots: LR shoots). The secondary metabolite content of the in vitro plant material was compared with that of the greenhouse growing plants. The quali-quantitative LC-DAD-ESI-MS analysis on the extracts from axillary proliferation shoots (AP shoots) showed significant production of caffeic acid derivatives while leaf callus and LR shoots, accumulated mainly alkamides. These results showed that the proper choice of the procedures for in vitro multiplication allowed us to obtain plant biomass able to produce the active compounds typical of E. angustifolia plants.  相似文献   

6.
Potassium chlorate (KClO3) treatments are known to promote flowering in longan plants. Potential effects of KClO3 on Phalaenopsis orchid flowering were investigated in the present study. However, increasing application concentrations of 2, 4, 8 and 16 mmol/L KClO3 delayed spike emergence by 5, 6, 18 and 26 days, respectively. Moreover, they reduced final spike length by 2.1%, 4.0%, 16.2% and 46.1%, respectively. Nonetheless, application of KClO3 at 4 and 8 mmol/L advanced the time to appearance of the first open flower by 13 and 24 days, respectively. Use of 8 mmol/L KClO3 also increased the number of floral buds by 16%. Treatments with KClO3 tended to reduce flower size. Overall, the data suggest that application of KClO3 at an appropriate concentration (e.g. 8 mmol/L) can increase the number of floral buds and advance the time to Phalaenopsis orchid flowering, but may reduce flower size.  相似文献   

7.
Temperate-zone crops require a period of winter chilling to terminate dormancy and ensure adequate bud break the following spring. The exact chilling requirement of blackcurrant (Ribes nigrum), a commercially important crop in northern Europe, is relatively unknown. Chill unit models have been successfully utilized to determine the optimum chilling temperature of a range of crops, with one chill unit equating to 1 h exposure to the optimum temperature for chill satisfaction. Two-year-old R. nigrum plants of the cultivars ‘Ben Gairn’, ‘Ben Hope’ and ‘Ben Tirran’ were exposed to temperatures of −10.1 °C, −3.4 °C, 0.1 °C, 1.5 °C, 2.1 °C, 3.4 °C or 8.9 °C (±0.7 °C) for durations of 0, 2, 4, 6, 8 or 10 weeks and multiple regression analyses used to determine the optimum temperature for chill satisfaction.  相似文献   

8.
Viable shoot cultures and weaned plants were obtained from cultured apical meristems with 10 Buddleia cultivars giving viabilities of 32–72%. The number of shoots produced, the micropropagation rate and the root number produced in vitro was higher in meristem derived shoots compared to those derived from shoot-tips. The subsequent growth rate of meristem derived plants, in the greenhouse, was also greater. The number of roots produced by conventional cuttings collected from meristem derived plants was significantly higher than in cuttings which were collected from plants derived from shoot-tips or from the original stock plants.Endogenous bacteria were not detected in either shoot cultures derived from meristems or in 10-week-old weaned plants derived from meristems whereas those derived from shoot-tips showed the presence of endogenous bacteria when sterilized explants were cultured on nutrient agar or on tryptic soy broth.Factors affecting adventitious bud and shoot production in leaf and internode explants was determined for ‘Lochinch’, ‘Border Beauty’, ‘Ile de France’ and ‘Pink Delight’ using meristem derived shoot cultures. Adventitious shoots appeared after 4 weeks of culture, in both types of explant when cultured on MS supplemented with 0.5–5.0 μM TDZ. The highest percentage regeneration was achieved from bisected internode explants cultured on 0.5 μM TDZ, with 93–100% regeneration among the cultivars whereas BA was less effective. The best response was obtained using 5.0 μM TDZ which gave over 10–11 shoots per explant in all bisected explants for all cultivars.  相似文献   

9.
Amphiploids were produced from pentaploid hybrids between Vaccinium corymbosum (4x) and Vaccinium ashei (6x) by colchicine treatment. Seeds of each parental species and those obtained by the interspecific crossing were treated with colchicine at 0, 500, 1000 and 2000 mg/l for 7 days, and the ploidy level of the seedlings was determined with flow cytometry. Either amphiploid (10x) or ploidy chimera (5x + 10x) was obtained from interspecific hybrid seeds treated with all colchicine concentrations, while no chromosome-doubled plants were obtained from both parents. Cross direction in interspecific hybridization affected the results of colchicine treatment and amphiploids were obtained only when V. corymbosum was used as the seed parent. In this cross, 17–25% of the seedlings turned to be amphidiploids or ploidy chimeras by treating with 500 mg/l colchicines for 7 days. These results indicate that susceptibility to colchicine may increase in the interspecific hybrid compared with the parental species but only when V. corymbosum was used as female parent.  相似文献   

10.
South African Proteaceae are adapted to the low soil phosphorus (P) concentrations of the Cape Floristic Region. The efficient P uptake by Proteaceae means that these plants experience phosphorus (P) toxicity at lower rhizosphere [P] than crop plants. This is only problematic when cultivating Proteaceae (and many plants from this region) on previously agricultural land with high residual soil [P]. In this study we hypothesize that P toxicity will result in element imbalances in leaves of Proteaceae and information from this study aims to facilitate ameliorative treatments. Phosphorus toxicity was induced on-farm in Leucadendron ‘Safari Sunset’ (Proteaceae) with subsequent mapping of element distribution in non-necrotic leaf tissue using micro particle-induced X-ray emission spectrometry. Phosphate supply up to 0.01 mM in a fertigation solution resulted in increased stem length of Leucadendron ‘Safari Sunset’ while P concentrations in excess of this resulted in decreased stem length, increased leaf [P] up to 0.25% (w/w) and, between 1 mM and 5 mM P supply, typical P toxicity symptoms were observed. High P supply (5 mM P) resulted in increased leaf [P] in most leaf tissues including the epidermis, where calculations from an equilibrium speciation model indicated that there was 30% more dissolved PO43− in the epidermis compared to leaves at low P supply (0 mM added P on soil with 34 mg P kg−1). Concomitantly, bundle sheath and epidermal [Ca] were reduced and 10% more Ca was predicted to be adsorbed and precipitated as hydrapatite at high P supply. High P supply resulted in increased leaf [Cl] and [Mn] in all tissues studied; decreased total leaf [Fe], bundle sheath, xylem, phloem and epidermal [Fe] and decreased total leaf [Zn] and xylem and phloem [Zn]. The observed symptoms of P toxicity in Leucadendron ‘Safari Sunset’ (necrosis in some plants, chlorosis and leaf rosetting) co-occurred with (1) excess PO43−, which may bind Ca in the epidermis (leading eventually to necrosis); (2) reduced [Fe] and increased [Mn] (leading to chlorosis) and (3) reduced total and vascular [Zn] (leading to leaf rosetting).  相似文献   

11.
Nolina recurvata Hemsl. is a very decorative indoor plant but difficult to micropropagate vegetatively. In vitro cuttings failed to induce adventitious rooting. Investigations for a rapid micropropagation using β-cyclodextrin added to the rooting medium has solved the problem. Rooted N. recurvata plantlets were obtained after successive stages of various culture media.Initiation and in vitro multiplication of this plant was possible with lateral buds cultured in Murashige and Skoog medium supplemented with 4.45 μmol of BA and 0.5 μmol of IBA. The number of axillary shoots by explant obtained was 6.In vitro rooting was obtained in MS medium (1/2 strength of minerals salts) supplemented with β-cyclodextrin. This substance, at 1.76 mmol associated with 5 μmol of IBA, improved quality and the rooting rate by 100%.  相似文献   

12.
The capability of the ‘Ball-Berry’ model (BB-model) in predicting stomatal conductance (gs) and water use efficiency (WUE) of potato (Solanum tuberosum L.) leaves under different irrigation regimes was tested using data from two independent pot experiments in 2004 and 2007. Data obtained from 2004 was used for model parameterization, where measurements of midday leaf gas exchange of potted potatoes were done during progressive soil drying for 2 weeks at tuber initiation and earlier bulking stages. The measured photosynthetic rate (An) was used as an input for the model. To account for the effects of soil water deficits on gs, a simple equation modifying the slope (m) based on the mean soil water potential (Ψs) in the soil columns was incorporated into the original BB-model. Compared with the original BB-model, the modified BB-model showed better predictability for both gs and WUE of potato leaves on the parameterization data set. The models were then tested using the data from 2007 where plants were subjected to four irrigation regimes: non-irrigation (NI), full irrigation (FI), partial root-zone drying (PRD), and deficit irrigation (DI) for 3 weeks during tuber initiation and earlier bulking stages. The simulation results showed that the modified BB-model better simulated gs for the NI and DI treatments than the original BB-model, whilst the two models performed equally well for predicting gs of the FI and PRD treatments. Although both models had poor predictability for WUE (0.47 < r2 < 0.71) of potato leaves, the modified BB-model was able to distinguish the effects of the irrigation regimes on WUE being that the WUE was generally greater for PRD than for FI and DI plants. Conclusively, the modified BB-model is capable of predicting gs and of accounting for the differential effects of irrigation regimes on WUE of potato leaves. This information is valuable for further simulating potato water use thereby optimizing WUE under field conditions.  相似文献   

13.
Emergence of multiple pollen tubes from single pollen grains occurred both in vitro and in vivo in sponge gourd (Luffa cylindrica (L.) Roem). The frequency with which pollen grains produced multiple pollen tubes in vivo (7.2%) was lower than that under in vitro conditions (14.9%). In pollen grains germinated in vitro, the total length of the multiple pollen tubes was greater than that of single pollen tubes, but individual tubes among the multiple tubes did not reach the same length as single tubes. Moreover, the growth of the single pollen tubes continued for a longer period in vitro than that of the multiple tubes. Fluorescence microscopy showed that callose was present throughout the pollen tube wall except in the apical part of growing pollen tubes, and nuclei moved into the longest of the multiple tubes. Results of Fourier transform infrared microspectroscopy indicated that abnormal cell wall components (peaks at 800–1000 cm−1) were more frequent in multiple pollen tubes lacking nuclei, and the pectin content (1733 cm−1) in multiple pollen tubes was much lower than that in single pollen tubes. These findings suggested that there were significant differences in pollen tube growth and wall composition between single and multiple pollen tubes, and that multiple pollen tubes had much less opportunity than single pollen tubes to reach the embryo sac and achieve double fertilization.  相似文献   

14.
Characteristics such as flower form, size and color of outer and inner perianths, anthocyanins in outer perianths, size, color and fertility of pollen and self-fertility of diploid and tetraploid lines regenerated via protoplast culture of Iris fulva were examined and compared with those of the diploid wild line. Among these characteristics, flower form, inner and outer perianth sizes of the tetraploid lines were noticeable, because these lines had upward flower forms and bigger flowers than diploid lines. Furthermore, reciprocal crosses between diploid or tetraploid lines of I. fulva and I. ensata and those of I. fulva and I. laevigata were performed. Three seedlings were obtained from the cross of tetraploid I. fulva × diploid I. laevigata through embryo rescue. One of them was identified as the interspecific hybrid between tetraploid I. fulva and I. laevigata by flow cytometoric (FCM), cytological and molecular (RAPD) analyses. This is the first report on production of hybrids from these lines. I. fulva has unique brown flowers, and this trait could be very useful for flower color breeding of I. laevigata which lacks this color. Therefore, the hybrid of I. fulva (4×) × I. laevigata may be the best available gene source for brown color breeding of this species.  相似文献   

15.
The effects of the NH4:NO3 ratio in replenishment solution on Rosa L. flower yield and the impact of NH4 substitution by urea on plant performance and on solution EC and pH have not been studied previously in closed (no leaching) hydroponic systems. A greenhouse experiment with six NH4:NO3:urea ratios (0:100:0, 12:88:0, 25:75:0, 50:50:0, 100:0:0 and 0:50:50) and two harvest cycles (winter and spring) was carried out to investigate these relationships. In winter, total and >40 cm cut flower yields were maximal in treatment 25:75:0. At lower NH4 percentages (12.5:87.5:0 and 0:100:0), growth container solution pH varied between 7.8 and 8.5, reducing P, Ca and Mn concentration in leaves and increasing dry matter allocated to them. At higher NH4 percentages, Ca uptake was inhibited, solution pH reached 3, and %P in leaves increased. Consequently, reducing sugars concentration in leaves increased and sucrose and starch concentrations decreased. A stepwise regression analysis indicated that the optimal NH4:NO3 ratio in feed solution is 40:60, with resulting solution pH of 5.9 in the growth container. In spring the maximum yield was obtained in treatment 0:50:50 and it exceeded the winter yield despite a higher solution EC (4.3 dS m−1 vs. 3.5 dS m−1 at harvest). The beneficial effect of urea (0:50:50 vs. 50:50:0) stemmed from the relatively lower NH4 concentration in solution, that alleviated the NH4–Ca uptake competition, and higher pH. The slope of the straight line relating [H+ efflux rate] to [NH4+ uptake rate] in treatments 25:75:0, 50:50:0 and 100:0:0 was 0.44 mol H+/mol NH4. In all other treatments the proton efflux was negligible.  相似文献   

16.
Genetic diversity of forty fig cultivars collected from five regions in Tunisia was investigated using amplified fragment length polymorphism (AFLP). A total of 342 reproducible bands amplified with six AFLP primer combinations were obtained. The high percentage of polymorphic bands (%PB) of 97.5 and the resolving power (Rp) collective rate value of 143 were scored. In addition, the polymorphism information content (PIC) values varied from 0.61 to 0.87 with an average of 0.77. Although cluster (UPGMA) and principal components analyses indicate that the cultivars’ clustering made independently both from the geographical origin, horticultural classifications and/or from the sex of trees. In addition, the observed variation suggests considerable differentiation among fig cultivars. The present data supports the common origin of the fig cultivars. Analysis of molecular variance (AMOVA) revealed that average ΦST value overall loci was 0.026, and the overall distribution pattern of molecular variation indicated that about 97.43% of the total variance was accounted by the within-region variance component. The remaining 2.5% (P < 0.001) of the variation was founded among cultivars of the prospected regions. Our results proved that AFLP markers are useful for germplasm discrimination as well as for investigation of fig patterns variation. The information may be useful to define conservation management program.  相似文献   

17.
To establish an efficient protocol of shoot regeneration from callus, effects of explant type, culture media and plant growth regulators on callus induction and shoot regeneration of Chinese jiaotou (Allium chinense) were evaluated. The results showed that basal plate was the best explant for callus induction (47.5%) when cultured on B5 medium supplemented with 0.1 mg l−1 6-benzylaminopurine (BA) and 1.0 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D), and B5 was the best medium to induce callus formation with 49.3% of the explants forming callus. The highest callus induction (65.2%) was achieved culturing basal plate on B5 medium supplemented with 0.1 mg l−1 BA and 1.0 mg l−1 2,4-D after 8 weeks of culture. The best callus proliferation was observed on B5 medium with 1.5 mg l−1 2,4-D. Shoots regenerated at the highest frequency of 58.8% with 4.5 shoots when calli were cultured on B5 medium with 0.1 mg l−1 BA and 1.0 mg l−1 a-naphthaleneacetic acid (NAA). This protocol provides a basis for future studies on genetic improvement and could be applied to large-scale multiplication systems for commercial nurseries of Allium chinense.  相似文献   

18.
The role of methyl jasmonate (MJ) in strawberry (Fragaria × ananassa Duch. cv Pajaro) fruit ripening was investigated by monitoring its endogenous concentrations in fruit at various stages of development and the effects of exogenously applied MJ at these stages on ethylene biosynthesis. The concentration of endogenous trans-MJ was significantly higher in the white fruit (31.7–162.2 ng g−1) and decreased sharply in half and fully ripe fruit. Higher concentrations of endogenous trans-MJ at the white stage of strawberry fruit development followed by a decline during fruit ripening indicate that MJ may play an important role in modulating fruit ripening. Significantly increased ethylene production was measured in the fruit when MJ was applied at white, half ripe and at fully ripe stage. The application of MJ (50 μM) resulted in significantly highest ethylene production and increased activities of 1-aminocyclopropane-1-carboxylic acid (ACC) synthase and ACC oxidase as compared to all other treatments. The effect of exogenously applied MJ on ethylene production, ACC synthase and ACC oxidase activities was dependent on concentration of MJ applied and on fruit developmental stage. In conclusion, MJ in strawberry modulates fruit ripening, as its concentration is higher in white fruit and is declined with the progression of ripening and exogenous application of MJ increases ethylene production, activities of ACC oxidase and ACC synthase depending upon the concentration of MJ applied and fruit developmental stage.  相似文献   

19.
Varietal differences in the total phenolic content and astringency in the skin and flesh were determined among the cultivars and local collections of hardy kiwifruit with a ploidy variance found in Japan. The average values of the total phenolic content in the skin and flesh were 2.66 and 0.18 g 100 g−1 FW, respectively. There were large varietal differences in the total phenolic content in the skin in the range of 1.3–5.0 g 100 g−1 FW. Kochi (tetraploid), while Gassan and ‘Mitsuko’ (hexaploid) contained a larger amount of total phenolics. High astringency was found in Gassan, ‘Mitsuko’ and ‘Hoko’ (hexaploids) and Kochi. HPLC analysis showed that the major components of phenolics in the flesh were (+)-catechin, chlorogenic acid, rutin, (−)-epicatechin and quercetin.  相似文献   

20.
Leaf area estimation is an important biometrical observation one has to do for comparing plant growth in field and pot experiments. In this study, a leaf area estimation model was developed for ginger (Zingiber officinale Roscoe), using linear measurements of leaf length (L) and maximum width (W). Leaves from five ginger varieties (Varada, Rejatha, Mahima, Maran and Himachal) were used to develop the model in 2006–2007. The actual leaf area (LA) was measured with a leaf area meter (LI-3100, LI-COR, Lincoln, NE, USA) and taken as reference LA. The linear measurements were used to build linear (LA = a + b × L × W) and power models (LA = α × (L × W)β) for each variety, as the modeling among variety were not different from each other, data for all five varieties have been pooled and compared with earlier models by graphical procedures and statistical criteria such as Mean Square Error (MSE), Root Mean Square Error (RMSE) and Chi-square (χ2). The selected model was validated during 2007–2008. The validation data set was used to produce a validation model for each variety by re-estimating the model parameters to develop the estimation model and the models were compared for consistency. The predicted LA (PLA) was compared with observed LA (OLA) by graphical procedures and lack of agreement was evaluated by calculating the relative bias, estimated by the mean of differences (d) and the standard deviation (SD) of the differences. Normality test was carried out by Spearman's rank correlation coefficient (rs) and residuals were normally distributed. Finally, the proposed model for leaf area estimation of ginger is LA = −0.0146 + 0.6621 × L × W, R2 = 0.997. This model can be reliably used for estimating leaf area of ginger non-destructively. The same equation can be extrapolated to all varieties and land races of ginger as it is vegetatively propagated crop with narrow genetic variability.  相似文献   

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