Prohexadione-calcium modifies growth and increases photosynthesis in strawberry nursery plants

2005 ◽  
Vol 85 (3) ◽  
pp. 671-677 ◽  
Author(s):  
J. Y. Reekie ◽  
P. R. Hicklenton ◽  
P. C. Struik

Prohexadione-calcium (ProCa) at an active ingredient concentration of 62.5 mg L-1 was applied as a foliar spray to Camarosa and Sweet Charlie strawberry (Fragaria × ananassa Duchesne) plants in growth chambers to assess its effects on dry weight allocation and growth over 42 d. The height, leaf number, leaf area, and specific leaf area (SLA) of daughter plants and the total dry weights of their leaves, stems and roots were all affected by ProCa treatments. Treated plants weighed less than untreated plants for the first 28 d after treatment, but by 42 d, all plants were similar in total weight regardless of treatment. ProCa-treated plants consistently allocated more dry weight to roots, and proportionally less to shoots, and were reduced in height, leaf area and SLA. ProCa increased net photosynthesis in plants grown in growth chambers and in the field. Plants grown in the field responded to ProCa earlier, and their photosynthetic rates were higher (i.e., 23–34% higher in daught ers and 34–41% higher in mothers) than those grown in growth chambers. Key words: Fragaria × ananassa, gibberellin biosynthesis inhibitor, growth analysis, net photosynthesis

Author(s):  
Humaid Rashid Moulin - Iyad Assi Obaid

    A field experiment was conducted at one of greenhouse belonged to College of agriculture – Diyala University. IRAQ, at fall season 2017 – 2018 in order to study the effect of foliar spray three concentrations of Sorbitol(0, 25, 50 gL-1) and Boric acid (B17%) at concentrations(0, 20, 40 mgL-1) on some growth vegetative and flowering of strawberry plant (Fragaria ananassa Duch) cv. Rubygum. using (R.CB.B.D) design with four replicate The result showed, the Sorbitol ,Boron and their interaction had significant effect on studied characters, The application of sorbitol at at 25 gL-1 spraying caused a significant increase in leave number, leaf area, plant leave area ,the vegetative dry weight. 57.880 leaf plant-1, 37.122 cm2.plant-1, 0.21482 m2.plant-1, 278.50 g.plant-1, respectively compared with control, also spraying of boric acid at 40mgL-1 recorded a significant increase in leave number, leaf area, plant leave area, the root dry weight reached 57.58 leaf plant-1, 36.975 cm2.plant-1, 0,21518 m2.plant-1, 11.669 g.plant-1 respectively, Whereas control treatment gave the lowest means of the above characters. The interaction between Sorbitol at 25gL-1 and Boron at 40mgL-1 spraying caused a significant increase in leave number, leaf area, plant leave area ,the, the vegetative dry weight, the root dry weight, reached to 65.890 leave.plant-1, 39.772 cm2.leave, 0.26228m2.plant-1, 84.670g.plant-1, 15.39 g.plant-1, respectively compared with control which gave the lowest means of the above characters. as well as spraying of the interaction between sorbitol at 0 and Boron at 20 mgL-1 gave a significantly increasing in number of flower reached 104.155 flower.plant-1 ,while the control recorded a lowest number of flower (82.274 flower.plant-1).    


Author(s):  
Y. Rajasekhara Reddy ◽  
G. Ramanandam ◽  
P. Subbaramamma ◽  
A. V. D. Dorajeerao

A field experiment was carried out during rabi season of 2018-2019, at college farm, College of Horticulture, Dr. Y.S.R. Horticultural University, Venkataramannagudem, West Godavari District, Andhra Pradesh. The experiment was laidout in a Randomised Block Design with eleven treatments (viz., T1- NAA @ 50 ppm, T2-NAA @ 100 ppm, T3-GA3 @ 50 ppm,  T4-GA3 @ 100 ppm, T5-Thiourea @ 250 ppm, T6-Thiourea @ 500 ppm, T7-28-Homobrassinolide @ 0.1 ppm, T8-28-Homobrassinolide @ 0.2 ppm, T9-Triacontinol @ 2.5 ppm, T10-Triacontinol @ 5 ppm, T11-(Control) Water spray) and three replications. The treatments were imposed at 30 and 45 DAT in the form of foliar spray. Foliar application of GA3@ 100 ppm (T4) had recorded the maximum plant height (108.20 cm), leaf area (9.53 cm2) and leaf area index (0.74). Foliar application of thiourea @ 250 ppm (T5) had recorded the maximum values with respect to number of primary branches (15.03 plant-1), number of secondary branches (83.40 plant-1), plant spread (1793 cm2 plant-1), fresh weight (376.29 g plant-1), dry weight (103.54 g plant-1) and number of leaves plant-1((298.8). The same treatment (T5) had recorded the highest values with respect to crop growth rate (1.44 gm-2d-1), chlorophyll-a (1.40 mg g-1), chlorophyll-b (0.076 mg g-1) and total chlorophyll contents (1.48 mg g-1) in the leaves.


Sensors ◽  
2020 ◽  
Vol 20 (22) ◽  
pp. 6501
Author(s):  
Mohammad Ajlouni ◽  
Audrey Kruse ◽  
Jorge A. Condori-Apfata ◽  
Maria Valderrama Valencia ◽  
Chris Hoagland ◽  
...  

Crop growth analysis is used for the assessment of crop yield potential and stress tolerance. Capturing continuous plant growth has been a goal since the early 20th century; however, this requires a large number of replicates and multiple destructive measurements. The use of machine vision techniques holds promise as a fast, reliable, and non-destructive method to analyze crop growth based on surrogates for plant traits and growth parameters. We used machine vision to infer plant size along with destructive measurements at multiple time points to analyze growth parameters of spring wheat genotypes. We measured side-projected area by machine vision and RGB imaging. Three traits, i.e., biomass (BIO), leaf dry weight (LDW), and leaf area (LA), were measured using low-throughput techniques. However, RGB imaging was used to produce side projected area (SPA) as the high throughput trait. Significant effects of time point and genotype on BIO, LDW, LA, and SPA were observed. SPA was a robust predictor of leaf area, leaf dry weight, and biomass. Relative growth rate estimated using SPA was a robust predictor of the relative growth rate measured using biomass and leaf dry weight. Large numbers of entries can be assessed by this method for genetic mapping projects to produce a continuous growth curve with fewer replicates.


Weed Science ◽  
1993 ◽  
Vol 41 (3) ◽  
pp. 394-402 ◽  
Author(s):  
Alex G. Ogg ◽  
Randall H. Stephens ◽  
David R. Gealy

Destructive growth analysis of field replacement series experiments with mayweed chamomile and dry field peas was used to determine the competitive relationship between the two species. Mayweed chamomile produced similar amounts of leaf area and dry weight per plant in a dry year and a wet year. On the other hand, dry field peas produced 20% more leaf area and 100% more dry weight per plant in the wet year compared to the dry year. Height, leaf area, and dry weight of peas reached maximum between bloom and pod-set, and then declined. Height and dry weight of mayweed chamomile increased steadily throughout the growing season. Mayweed chamomile leaf area reached a maximum at the beginning of flower stem elongation. Initially, the relative growth rate of mayweed chamomile was about three times greater than the rate for peas, but by 40 to 48 d after planting, rates were similar for both species. Relative yields and relative crowding coefficients for dry weight showed that peas were 3 to 20 times more aggressive than mayweed chamomile. Results of these experiments show that mayweed chamomile is a weak competitor against peas, but because it continues to grow after peas senesce, it could interfere with crop harvest.


1997 ◽  
Vol 75 (2) ◽  
pp. 213-219 ◽  
Author(s):  
Xiuming Hao ◽  
Beverley A. Hale ◽  
Douglas P. Ormrod

Tomato (Lycopersicon esculentum Mill.) plants were exposed, in controlled environments with 2.7 kJ/(m2 ∙ day) background ultraviolet-B (UV-B) radiation from fluorescent and incandescent lamps, to ambient (380 μL ∙ L−1) or elevated (600 μL−1) CO2 combined with a total of 7.2 or 13.1 kJ/(m2 ∙ day) UV-B radiation to determine effects on growth and photosynthesis. Ten consecutive days of exposure to the higher level of UV-B significantly reduced total and stem dry weight, leaf area, and plant height compared with the lower level. Only leaf area and plant height were significantly reduced after 19 consecutive days of exposure. To investigate whether plants recover from UV-B damage, the UV-B exposures were halted for 3 days after 19 days of UV-B exposure and then restarted for a further 2 days. The largest reduction in plant growth was found after 3 days with no UV-B followed by 2 days of the higher level of UV-B. Plants did not recover from UV-B damage during the 3 days with background UV-B. Significant CO2xUV-B interactions were detected on stem dry weight after 10 consecutive days of the higher level of UV-B and on total dry weight, leaf dry weight, stem dry weight, and plant height after 3 days with no UV-B followed by 2 days of the higher level of UV-B. The higher dose of enhanced UV-B resulted in more severe damage at 600 μL ∙ L−1 CO2, than at ambient CO2. The higher level of UV-B did not affect the leaf net photosynthesis rate on a leaf area basis, although this UV-B level may have inhibited tomato growth through reducing the photosynthetic area. UV-absorbing compounds in leaves in the highest UV-B radiation level for 19 days were greater than for leaves with the lower dose. These UV-absorbing compounds in the higher UV-B dose diminished more than in the lower dose plants during the 3 days without UV-B. The UV-absorbing compounds maintained by plants exposed to the highest level of UV-B radiation may have protected plants from UV-B damage, particularly between 10 and 19 consecutive days of exposure. Key words: CO2, growth, Lycopersicon esculentum Mill., photosynthesis, tomato, ultraviolet-B radiation (UV-B), UV-absorbing compounds.


2020 ◽  
Vol 26 (4) ◽  
pp. 537-544
Author(s):  
Abdul Kareem A.J. Mohammad Saeed

Abstract An experiment was conducted during the season 2018-2019 in the lath house to study the effect of foliar spray with Ascorbic Acid (AsA) and Salicylic Acid (SA) on vegetative and flowering growth traits of Gazania (Gazania rigens L.) cv. Frosty Kiss Mixed. The experiment was designed as a factorial experiment (3×3) in Randomized Complete Blocks Design (RCBD) with three replicates. Plants were sprayed with concentrations of 0, 100, and 200 mg L-1 of AsA, and 0, 150 and 300 mg L-1 of SA. Foliar spray with 200 mg L-1 of AsA was superior on increasing number of leaves (40.00), number of suckers (9.22), leaf area (2174.09 cm2), leaves dry weight (6.36 g), number of flowers (5.64), early of flowering date (97.22 days), flower fresh and dry weight (4.78 g) (0.51 g) respectively, while spray with a concentration of 100 mg L-1 led to increase flower diameter (6.37 cm) and flowering duration (10.85 days). Foliar spray with SA improved all vegetative and flowering traits. Treatment of 300 mg L-1 was the most significant effect in increasing number of leaves (39.56), leaf area (2182.06 cm2), leaves fresh weight (43.93 g), number of flowers (5.83), flower diameter (6.31 cm), early of flowering date (98.07 days), and flower dry weight (0.50 g). The interaction effect between the studied factors was significant in all studied traits. Treatment of AsA200×SA150 was the most effective and gave the best results in terms of number of suckers (9.11), dry weight of leaves (6.49 g), number of flowers (5.87), flower diameter (6.44 cm), flowering date (96.98 days), flowering duration (10.89 days).


Agrin ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 39
Author(s):  
Bhaskara Anggarda Gathot Subrata ◽  
Stefany Darsan

Penelitian bertujuan untuk mengetahui efektivitas pemberian hara mikro melalui akar dan daun. Penelitiandilaksanakan dengan menggunakan Rancangan Acak Lengkap (RAL) faktor tunggal. Perlakuan berupa kontrol,pupuk mikro lewat media, pupuk mikro lewat daun. Masing-masing perlakuan diulang 6 kali. Media tanam berupapasir yang sudah dimasukan ke dalam bak penanaman, setelah itu tanam benih kangkung dengan jarak 10x10 cmpada setiap bak. Lalu aplikasikan pupuk melalui media atau daun seminggu sekali. Pengamatan yang dilakukanmeliputi tinggi tanaman dan kehijauan daun dengan SPAD 502 untuk tiap minggunya; aktivitas nitrate reduktase,kandungan klorofil a, klorofil b, dan klorofil total, bobot kering batang, bobot kering tajuk, bobot kering daun,bobot kering akar, luas daun (LD), serta analisis pertumbuhan tanaman, meliputi nisbah laju daun (NLD), luasdaun khas (LDK), bobot daun khas (BDK). Berdasarkan penelitian yang telah dilakukan, pemberian pupuk cairmelalui media maupun daun belum mampu meningkatkan pertumbuhan dan hasil tanaman kangkung. Perlakuanpada daun cenderung menunjukan hasil yang lebih tinggi dibandingkan perlakuan pada media pada semuaparameter pengamatan.Kata kunci: efektivitas, hara mikro, akar dan daunABSTRACTThe aim of this research is to know the effectiveness of micro nutrient giving through root and leaf. Theresearch was conducted by using Completely Randomized Design (CRD) of single factor. Treatment of control,micro-fertilizer through the media, micro-fertilizer through the leaves. Each treatment was repeated 6 times.Planting media in the form of sand that has been inserted into the tub of planting, after that plant the seeds ofkangkung with a distance of 10x10 cm in each tub. Then apply the fertilizer through the media or leaves once aweek. Observations included plant height and greenery of leaves with SPAD 502 for each week; nitrate reductaseactivity, chlorophyll a, chlorophyll b, and total chlorophyll, dry weight of stalk, dry weight of canopy, leaf dryweight, root dry weight, leaf area, and plant growth analysis, including leaf rate ratio, typical leaf area, typicalleaf weight. Based on the research that has been done, the application of liquid fertilizer through the media andleaves has not been to increase the growth and yield of kangkung. Treatment on the leaves tend to show higherresults than treatment on media at all observation parameter.Keywords: effectiveness, micro nutrients, roots and leaves


HortScience ◽  
2016 ◽  
Vol 51 (7) ◽  
pp. 843-846 ◽  
Author(s):  
Toshio Shibuya ◽  
Ryosuke Endo ◽  
Yoshiaki Kitaya ◽  
Saki Hayashi

Light with a higher red to far-red ratio (R:FR) than sunlight reduces plant growth, but the cause has not been firmly established. In the present study, cucumber seedlings were grown under normal light (similar to sunlight; R:FR = 1.4) from metal-halide lamps or high-R:FR light (R:FR = 4.3) created by transmitting their light through FR-absorbing film, and then their growth parameters and photosynthesis were compared. The relative growth rate (RGR) at high R:FR was 92% of that under normal R:FR, although the net assimilation rate (NAR) did not differ between the treatments, indicating that changes in net photosynthesis per unit leaf area did not cause the growth inhibition at high R:FR. The CO2 exchange per unit leaf area did not differ between the treatments, which supports this hypothesis. The leaf area ratio (LAR) of total plant dry weight of high R:FR seedlings to that of normal R:FR seedlings was also 92%. This suggests that growth suppression in the high R:FR seedlings was caused mainly by decreased LAR. The specific leaf area (SLA) and leaf weight ratio (LWR), components of LAR, under high-R:FR light were 89% and 105%, respectively, of those under normal light, indicating that the smaller LAR at high R:FR mainly results from suppressed leaf enlargement per unit leaf dry matter.


HortScience ◽  
1999 ◽  
Vol 34 (6) ◽  
pp. 1064-1067 ◽  
Author(s):  
D.C. Ferree ◽  
D.M. Scurlock ◽  
J.C. Schmid

`Seyval blanc' and `Vidal blanc' grapevines (Vitis sp.) grown in large containers were root-pruned at different severities and/or stages of development and the effects on growth of both cultivars and fruiting of `Seyval blanc' were determined. As the severity of root pruning increased, stomatal conductance (gs) and transpiration (E) decreased and the number of wilted leaves increased in both cultivars. In both cultivars, root pruning reduced net photosynthesis (Pn) and E for as long as 18 to 20 days, as well as total leaf area and dry weight of leaves and petioles plus tendrils. The reductions were proportional to the degree of root pruning. A similar pattern existed for cane and root tissue of `Vidal blanc'. As the severity of root pruning increased, berry and cluster weight, and titratable acidity (TA) of `Seyval blanc' decreased. There was no effect of root pruning on berries per cluster, soluble solids content (SSC), or pH of the juice. No interaction was significant for any factor between time of root pruning and fruiting measured on `Seyval blanc' vines. Root pruning at bloom reduced leaf area, number of leaves, and dry weight of petioles, trunks, and canes. Root pruning at veraison had no effect on any vegetative or fruit parameters. Fruiting `Seyval blanc' vines had less leaf area and smaller petiole and cane dry weights than did nonfruiting vines.


1984 ◽  
Vol 14 (6) ◽  
pp. 850-854 ◽  
Author(s):  
S. B. Rood ◽  
G. Daicos ◽  
T. J. Blake

Weekly applications of 0.4 mg gibberellic acid (GA) in 8 μL 95% ethanol micropipetted onto shoots of rooted cuttings increased Populuseuramericana (Dode) Guinier height growth by 54% and shoot dry weight by 25% after 21 days. Total leaf area increased by 21% as a result of more rapid leaf production and slightly larger leaf sizes. Root growth was unaffected by GA treatment. The observed GA-induced acceleration resulted from an increase in relative growth rate while mean net assimilation rate was unaffected. Owing to a substantial increase in the number and size of leaves, the leaf area ratio, representing the ratio of photosynthesizing to respiring material, increased. While direct micropipette application of GA promoted height growth and primary shoot dry weight accumulation, GA application through either foliar spray or soil drench also promoted the growth of secondary shoots. Application of GA to shoots was more effective in promoting shoot growth than application through the roots. Direct GA application also promoted the growth of P. alba L. × P. grandidentata Michx. and P. × canescens (Ait.) Smith × P. alba × P. grandidentata. Thus, GA can be used for hastening early growth of these trees under winter greenhouse conditions.


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