Influences of Harvesting Time and Plucking Position of the Second Crop on New Shoot Growth and Yield of the First Crop of the Next Year for the Tea (Camellia sinensis L.).

Vegetative growth control of apples (Malus × domestica Borkh.) is necessary to maintain a balance between growth and cropping. Pruning is a labour-intensive management practice to achieve this and intrinsically stimulates new growth. Prohexadione-calcium (PC) is a plant bio-regulator that effectively regulat es the shoot extension growth of apples and other tree fruits. Previous research has demonstrated that its efficacy can vary based on the use of spray surfactants and adjuvants. This study investigated the efficacy of two rates of Apogee™, the commercial form of PC, used in combination with the spray surfactants Sylgard 309 and LI 700, on extension shoot growth and yield parameters. Experiments were conducted in Ontario on Empire and Nova Scotia on Royal Court™ Cortland apples. Treatments of 0, 75 or 125 mg L-1 PC, with and without either 0.5% (vol/vol.) LI 700 surfactant or 0.05% (vol/vol) Sylgard 309 surfactant were applied to Empire trees, and 75 or 125 mg L-1 PC, with or without 0.5% (vol/vol) LI 700, were applied to Royal Court™ trees. An untreated control treatment was also included for comparison purposes. A total of two sprays were applied to the Empire trees and a total of three sprays were applied to the Royal Court™ trees. PC significantly decreased the vegetative growth of Empire and Royal Court™ trees by approximately 18 to 44%, respectively, and the efficacy of PC was enhanced when combined with either Sylgard 309 or LI 700 surfactant. No additional benefit in vegetative growth control was gained when using Apogee™ at rates of 125 mg L-1 PC, relative to 75 mg L-1 PC. The rate of Apogee™ did not influence the number of fruit or yield per tree or mean fruit size of either cultivar. For Empire, LI 700 and Sylgard 309 significantly reduced the number of fruit per tree, resulting in lower yields and crop densities. In addition, higher mean fruit weights, and a greater distribution of fruit in the larger size categories were observed for LI 700. Fruit from Royal Court trees treated with the highest rate of Apogee™ had higher crop densities, poorer coloured fruit, and a higher percentage of fruit less than 60 mm in diameter. These data provide support for the use of alternative surfactants with Apogee™ other than those listed on the US and Canadian product labels. Key words: Apogee™, Empire, Cortland, Regalis, calcium 3-oxido-5-oxo-4-propionylcyclohex-3-enecarboxylate, surfactant

Download Full-text

Reduced growth and yield of wheat with conservation cropping. I. Field studies in the first year of the cropping phase

Australian Journal of Agricultural Research ◽

10.1071/ar9940511 ◽

1994 ◽

Vol 45 (3) ◽

pp. 511 ◽

Cited By ~ 37

Author(s):

JA Kirkegaard ◽

JF Angus ◽

PA Gardner ◽

W Muller

Keyword(s):

Shoot Growth ◽

Plant Density ◽

Root Zone ◽

Field Studies ◽

Growth And Yield ◽

Rooting Depth ◽

First Year ◽

Mineral N ◽

Stubble Retention ◽

Direct Drilling

An experiment was conducted on a red earth at Harden, N.S.W., to investigate the effects of tillage and stubble management on the growth and yield of wheat in the first year of conservation cropping. Treatments involved stubble-management systems of incorporation, burning or retention combined with tillage systems of either direct drilling or minimum tillage. The experiment was conducted on an oat stubble of 3.9 t ha-1. Direct drilling and stubble retention both reduced seedling growth by 15%, compared to cultivated and stubble burnt treatments, but had no effect on plant density or tillering. The effects on shoot growth were additive and persisted until maturity, leading to grain yields which varied from 2.16 t ha-1 for the stubble-mulched, direct-drilled treatment to 3.20 t ha-1 for the burned-stubble, minimum-till treatment. Direct drilling reduced the total root length in the profile (0-160 cm) at anthesis by 40%, but there was no effect of stubble retention. Reduced shoot growth and rooting depth on direct-drilled and stubble-retained treatments reduced the recovery of water and mineral N by the crop and increased the leaching of mineral N below the root zone. Early shoot growth reductions on direct-drilled plots were not related to levels of soil water, mineral nitrogen (N) or soil temperature. Reduced shoot growth was associated with increased severity of Rhizoctonia in some direct drilled plots, but growth reductions often occurred in the absence of obvious symptoms. High soil strength (>2 MPa) in the top 10 cm of soil may have contributed to reduced growth, although the exact mechanism remains unclear. Reduced growth associated with the presence of stubble was not caused by immobilization of N or increased leaf disease, although reduced soil temperatures may have been partly responsible.

Download Full-text

Modelling shoot growth and yield of Ceylon tea cultivar TRI-2025 (Camellia sinensis (L.) O. Kuntze)

The Journal of Agricultural Science ◽

10.1017/s0021859618000229 ◽

2018 ◽

Vol 156 (2) ◽

pp. 200-214 ◽

Cited By ~ 4

Author(s):

H. A. S. L. Jayasinghe ◽

L. D. B. Suriyagoda ◽

A. S. Karunarathne ◽

M. A. Wijeratna

Keyword(s):

Leaf Area ◽

Model Calibration ◽

Shoot Growth ◽

Growth And Yield ◽

Growth Data ◽

Dry Matter Partitioning ◽

Validation Data ◽

Tea Shoot ◽

Tea Cultivar ◽

Validation Stage

AbstractThe present study was aimed at stimulating the growth and yield of Sri Lankan tea cultivar TRI 2025 grown in different climatic regions in the country. The model was developed and calibrated using weather, crop and soil data collected from different climatic zones. The model is designed to simulate shoot replacement cycle, leaf area of a shoot, shoot growth, dry matter partitioning and tea shoot yield. The model was validated using shoot development and growth data not used for model calibration. These validation data were collected from low, mid and high elevations representing temperature and rainfall gradients in the country. Model calibration showed that thermal time required to initiate the fish leaf, 1st, 2nd and 3rd normal leaf in a tea shoot from the time of natural senescence of the scale leaves were 129, 188, 235, 296 °C days, respectively, and a tea shoot reached the harvestable stage after 393 °C days. The model simulated leaf area (cm2) and fresh weight (g/m2) of tea shoots at different developmental stages and locations which were in good agreement with the measured values at the validation stage (R2 > 0.92 and 0.98, respectively). Similarly, simulated shoot yields (g/m2/month) at the validation stage were strongly correlated with the measured values (n = 12, R2 > 0.58, RMSE = 5–17 g/m2/month). Thus, the model can be used to estimate the shoot yield of tea cultivar TRI 2025 grown in different climatic conditions in Sri Lanka. Areas requiring further improvements to the model are also discussed.

Download Full-text

Effects of waterlogging in the spring on soil conditions and the growth and yield of spring barley in three cultivation systems

The Journal of Agricultural Science ◽

10.1017/s0021859600085166 ◽

1989 ◽

Vol 112 (2) ◽

pp. 265-276 ◽

Cited By ~ 4

Author(s):

D. R. Hodgson ◽

G. M. Whiteley ◽

Anna E. Bradnam

Keyword(s):

Grain Yield ◽

Shoot Growth ◽

Spring Barley ◽

Oxygen Flux ◽

Growth And Yield ◽

Soil Conditions ◽

N Recovery ◽

Redox Potentials ◽

Cultivation Systems ◽

Normal Rainfall

SummaryExperiments were carried out in 1985 and 1986 on a sandy clay–loam to investigate the effects of above average rainfall in May and early June on the growth of the spring barley cv. Klaxon in three systems of cultivation. The cultivation treatments, ploughing (P), shallow-tine cultivation (S) and direct drilling (D), had been repeated on the same plots and cropped with spring barley each year since 1971.A total of 112 mm water was applied to the waterlogged subplots in 1985 and 168 mm in 1986.Compared with plots receiving the normal seasonal rainfall, extra water had no effect on shoot or grain yield in 1985 (mean grain yield 6·38 t/ha) and there were no significant differences between cultivation systems. In 1986, in contrast, water, in excess of normal rainfall, depressed both shoot growth and grain yield (mean grain yields 4·49 and 4·07 t/ha for the normal rainfall and the additional water treatments, respectively), the effect being greater on P than on either S or D.In both years, saturation was achieved in the topsoil for a prolonged period during May and early June in the waterlogged subplots. In 1985 this was associated with a period of low oxygen flux and low redox potential, but this did nothave a significant effect on root or shoot growth. In 1986 there was no comparable period of reduced aeration, nor any significant differences in oxygen flux or redox potentials between water and cultivation treatments. In 1986, reduced growth and yield were directly associated with a mean reduction in N recovery by shoots of 36 kg N/ha, the effect being greatest on the ploughed plots where water was added. The results do not support the hypothesis that waterlogging per seaffects the growth of barley more on ploughed than on direct-drilled land.

Download Full-text

Reduced growth and yield of wheat with conservation cropping. II. Soil biological factors limit growth under direct drilling

Australian Journal of Agricultural Research ◽

10.1071/ar9950075 ◽

1995 ◽

Vol 46 (1) ◽

pp. 75 ◽

Cited By ~ 39

Author(s):

JA Kirkegaard ◽

R Munns ◽

RA James ◽

PA Gardner ◽

JF Angus

Keyword(s):

Shoot Growth ◽

Dominant Role ◽

Growth And Yield ◽

Cultivated Plants ◽

Biological Factors ◽

Wheat Seedlings ◽

Sowing Depth ◽

Cultivated Soil ◽

Controlled Environments

Wheat was grown in intact cores of soil removed from a field experiment in which seedlings had grown more slowly in direct-drilled soil than in cultivated soil. Experiments were conducted in controlled environments to resolve (1) whether shallower sowing of direct-drilled crops caused slower growth, (2) whether the soil factors causing the slower growth were physical or biological and (3) if biological, whether Rhizoctonia solani was the major pathogen. The conditions of the experiments removed possible constraints of water and nutrient supply but otherwise simulated the environment of wheat seedlings in southern Australia. Shallower sowing led to faster emergence and increased seedling growth, but irrespective of sowing depth, direct-drilled plants grew more slowly than plants in cultivated soil. Shoot growth of direct-drilled plants was 25-65% less than that of cultivated plants. These growth reductions were largely overcome by sterilizing the soil with y radiation or by fumigation with methyl bromide, indicating that biological factors were primarily responsible. Rhizoctonia was implicated as the cause of the reduced shoot growth when infection was severe (>3 on a 0-5 scale). There was no correlation between infection severity and shoot growth at moderate levels (<3) and significant reductions in shoot growth occurred in the absence of Rhizoctonia. These reductions were evident on the first leaf suggesting a direct influence on shoot growth rather than one mediated through inadequate uptake of water or nutrients. Infection of the germinating seed by Pythium spp. or the effects of phytohormones produced by inhibitory bacteria on the roots are possible causes of reduced shoot growth of direct-drilled seedlings. The dominant role of biological factors in determining plant response to soil management indicates the need for further studies to identify the organisms responsible, to determine the mechanism by which they influence shoot growth, and the effect of management on their populations and activity.

Download Full-text

Modelling the Growth and Yield of Tea ( Camellia sinensis L.) in Sri Lanka

IFAC Proceedings Volumes ◽

10.1016/s1474-6670(17)44408-9 ◽

1997 ◽

Vol 30 (5) ◽

pp. 51-56

Author(s):

Josef Eitzinger ◽

Ananda Anandacoomaraswamy

Keyword(s):

Sri Lanka ◽

Camellia Sinensis ◽

Growth And Yield

Download Full-text

Influence of Mineral Salts on Shoot Growth and Metabolite Biosynthesis in Tea Tree (Camellia sinensis L.)

Korean Journal of Horticultural Science and Technology ◽

10.7235/hort.2015.14055 ◽

2015 ◽

Vol 33 (1) ◽

pp. 106-113

Author(s):

Yong Duck Kim ◽

Jae Gill Yun ◽

Yeong Rong Seo ◽

Chandrakant S. Karigar ◽

Myung Suk Choi

Keyword(s):

Camellia Sinensis ◽

Shoot Growth ◽

Mineral Salts ◽

Tea Tree

Download Full-text

Root and aerial growth in early-maturing peach trees under two crop load treatments

Spanish Journal of Agricultural Research ◽

10.5424/sjar/2017152-10714 ◽

2017 ◽

Vol 15 (2) ◽

pp. e0803 ◽

Cited By ~ 6

Author(s):

Isabel Abrisqueta ◽

Wenceslao Conejero ◽

Lidia López-Martínez ◽

Juan Vera ◽

M. Carmen Ruiz Sánchez

Keyword(s):

Root Growth ◽

Shoot Growth ◽

Growth Dynamics ◽

Fruit Growth ◽

Growth And Yield ◽

Crop Load ◽

Fruit Thinning ◽

Early Maturing ◽

Peach Trees ◽

High Level

The objectives of the paper were to study the pattern of root growth (measured by minirhizotrons) in relation to trunk, fruit and shoot growth and the effects of crop load on tree growth and yield in peach trees. Two crop load (commercial and low) treatments were applied in a mature early-maturing peach tree orchard growing in Mediterranean conditions. Root growth dynamics were measured using minirhizotrons during one growing season. Shoot, trunk and fruit growth were also measured. At harvest, all fruits were weighed, counted and sized. Roots grew throughout the year but at lower rates during the active fruit growth phase. Root growth was asynchronous with shoot growth, while root and trunk growth rates were highest after harvest, when the canopy was big enough to allocate the photo-assimilates to organs that would ensure the following season’s yield. Shoot and fruit growth was greater in the low crop load treatment and was accompanied by a non-significant increase in root growth. High level of fruit thinning decreased the current yield but the fruits were more marketable because of their greater size.

Download Full-text

Growth and Yield of Tomato Plants in Response to Age of Transplants

Journal of the American Society for Horticultural Science ◽

10.21273/jashs.116.3.416 ◽

1991 ◽

Vol 116 (3) ◽

pp. 416-420 ◽

Cited By ~ 15

Author(s):

Daniel I. Leskovar ◽

Daniel J. Cantliffe ◽

Peter J. Stoffella

Keyword(s):

Lycopersicon Esculentum ◽

Root Growth ◽

Shoot Growth ◽

Total Yield ◽

Production Costs ◽

Growth And Yield ◽

Irrigation Systems ◽

Tomato Plants ◽

Chl A ◽

Over Time

Studies were conducted to evaluate growth of tomato (Lycopersicon esculentum Mill.) transplants in the field in response to age of transplants in Spring and Fall 1989. Transplants were 2 (2W), 3 (3W), 4 (4W), 5 (SW), or 6 (6W) weeks old. Drip and subseepage irrigation were used. In spring, older transplants produced more shoot and root growth up to 2 (T2) weeks after transplanting. At 3 (T3) and 4 (T4) weeks after transplanting, there were no differences between 4W, 5W, and 6W transplants. These trends were independent of irrigation systems. Total yield and early yield were similar for all transplant ages. In fall, shoot growth increased linearly with increasing transplant age at TO, but not thereafter. Chlorophyll a + b increased over time, but no treatment differences were found at T4. At planting, 2W transplants had a higher Chl a: b ratio than older transplants. This difference was reduced at T1 and T2 and became insignificant at T4. These results indicate that no improvement in yields was obtained using the traditional older transplants. Younger transplants might be used to achieve rapid seedling establishment with-minimal transplant production costs.

Download Full-text